1
|
Cai L, Argunşah AÖ, Damilou A, Karayannis T. A nasal chemosensation-dependent critical window for somatosensory development. Science 2024; 384:652-660. [PMID: 38723089 DOI: 10.1126/science.adn5611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 04/05/2024] [Indexed: 05/31/2024]
Abstract
Nasal chemosensation is considered the evolutionarily oldest mammalian sense and, together with somatosensation, is crucial for neonatal well-being before auditory and visual pathways start engaging the brain. Using anatomical and functional approaches in mice, we reveal that odor-driven activity propagates to a large part of the cortex during the first postnatal week and enhances whisker-evoked activation of primary whisker somatosensory cortex (wS1). This effect disappears in adult animals, in line with the loss of excitatory connectivity from olfactory cortex to wS1. By performing neonatal odor deprivation, followed by electrophysiological and behavioral work in adult animals, we identify a key transient regulation of nasal chemosensory information necessary for the development of wS1 sensory-driven dynamics and somatosensation. Our work uncovers a cross-modal critical window for nasal chemosensation-dependent somatosensory functional maturation.
Collapse
Affiliation(s)
- Linbi Cai
- Laboratory of Neural Circuit Assembly, Brain Research Institute (HiFo), University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- Neuroscience Center Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Ali Özgür Argunşah
- Laboratory of Neural Circuit Assembly, Brain Research Institute (HiFo), University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- Neuroscience Center Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Angeliki Damilou
- Laboratory of Neural Circuit Assembly, Brain Research Institute (HiFo), University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- Neuroscience Center Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Theofanis Karayannis
- Laboratory of Neural Circuit Assembly, Brain Research Institute (HiFo), University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- Neuroscience Center Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- University Research Priority Program (URPP), Adaptive Brain Circuits in Development and Learning (AdaBD), University of Zurich, CH-8057 Zurich, Switzerland
| |
Collapse
|
2
|
Shipkov D, Nasretdinov A, Khazipov R, Valeeva G. Synchronous excitation in the superficial and deep layers of the medial entorhinal cortex precedes early sharp waves in the neonatal rat hippocampus. Front Cell Neurosci 2024; 18:1403073. [PMID: 38737704 PMCID: PMC11082381 DOI: 10.3389/fncel.2024.1403073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Accepted: 04/15/2024] [Indexed: 05/14/2024] Open
Abstract
Early Sharp Waves (eSPWs) are the earliest pattern of network activity in the developing hippocampus of neonatal rodents. eSPWs were originally considered to be an immature prototype of adult SPWs, which are spontaneous top-down hippocampal events that are self-generated in the hippocampal circuitry. However, recent studies have shifted this paradigm to a bottom-up model of eSPW genesis, in which eSPWs are primarily driven by the inputs from the layers 2/3 of the medial entorhinal cortex (MEC). A hallmark of the adult SPWs is the relay of information from the CA1 hippocampus to target structures, including deep layers of the EC. Whether and how deep layers of the MEC are activated during eSPWs in the neonates remains elusive. In this study, we investigated activity in layer 5 of the MEC of neonatal rat pups during eSPWs using silicone probe recordings from the MEC and CA1 hippocampus. We found that neurons in deep and superficial layers of the MEC fire synchronously during MEC sharp potentials, and that neuronal firing in both superficial and deep layers of the MEC precedes the activation of CA1 neurons during eSPWs. Thus, the sequence of activation of CA1 hippocampal neurons and deep EC neurons during sharp waves reverses during development, from a lead of deep EC neurons during eSPWs in neonates to a lead of CA1 neurons during adult SPWs. These findings suggest another important difference in the generative mechanisms and possible functional roles of eSPWs compared to adult SPWs.
Collapse
Affiliation(s)
- Dmitrii Shipkov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Azat Nasretdinov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
- INMED - INSERM, Aix-Marseille University, Marseille, France
| | - Guzel Valeeva
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| |
Collapse
|
3
|
Ecker A, Egas Santander D, Bolaños-Puchet S, Isbister JB, Reimann MW. Cortical cell assemblies and their underlying connectivity: An in silico study. PLoS Comput Biol 2024; 20:e1011891. [PMID: 38466752 PMCID: PMC10927091 DOI: 10.1371/journal.pcbi.1011891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 02/05/2024] [Indexed: 03/13/2024] Open
Abstract
Recent developments in experimental techniques have enabled simultaneous recordings from thousands of neurons, enabling the study of functional cell assemblies. However, determining the patterns of synaptic connectivity giving rise to these assemblies remains challenging. To address this, we developed a complementary, simulation-based approach, using a detailed, large-scale cortical network model. Using a combination of established methods we detected functional cell assemblies from the stimulus-evoked spiking activity of 186,665 neurons. We studied how the structure of synaptic connectivity underlies assembly composition, quantifying the effects of thalamic innervation, recurrent connectivity, and the spatial arrangement of synapses on dendrites. We determined that these features reduce up to 30%, 22%, and 10% of the uncertainty of a neuron belonging to an assembly. The detected assemblies were activated in a stimulus-specific sequence and were grouped based on their position in the sequence. We found that the different groups were affected to different degrees by the structural features we considered. Additionally, connectivity was more predictive of assembly membership if its direction aligned with the temporal order of assembly activation, if it originated from strongly interconnected populations, and if synapses clustered on dendritic branches. In summary, reversing Hebb's postulate, we showed how cells that are wired together, fire together, quantifying how connectivity patterns interact to shape the emergence of assemblies. This includes a qualitative aspect of connectivity: not just the amount, but also the local structure matters; from the subcellular level in the form of dendritic clustering to the presence of specific network motifs.
Collapse
Affiliation(s)
- András Ecker
- Blue Brain Project, École polytechnique fédérale de Lausanne (EPFL), Campus Biotech, Geneva, Switzerland
| | - Daniela Egas Santander
- Blue Brain Project, École polytechnique fédérale de Lausanne (EPFL), Campus Biotech, Geneva, Switzerland
| | - Sirio Bolaños-Puchet
- Blue Brain Project, École polytechnique fédérale de Lausanne (EPFL), Campus Biotech, Geneva, Switzerland
| | - James B. Isbister
- Blue Brain Project, École polytechnique fédérale de Lausanne (EPFL), Campus Biotech, Geneva, Switzerland
| | - Michael W. Reimann
- Blue Brain Project, École polytechnique fédérale de Lausanne (EPFL), Campus Biotech, Geneva, Switzerland
| |
Collapse
|
4
|
Sharma H, Azouz R. Global and local neuronal coding of tactile information in the barrel cortex. Front Neurosci 2024; 17:1291864. [PMID: 38249584 PMCID: PMC10796699 DOI: 10.3389/fnins.2023.1291864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 11/24/2023] [Indexed: 01/23/2024] Open
Abstract
During tactile sensation in rodents, the whisker movements across surfaces give rise to intricate whisker motions that encompass discrete and transient stick-slip events, effectively conveying valuable information regarding surface properties. These surface characteristics are transformed into cortical neuronal responses. This study examined the coding strategies underlying these transformations in rat whiskers. We found that changes in surface coarseness modified the number and magnitude of stick-slip events, which in turn both modulated properties of neuronal responses. Global changes in the number of stick-slip events primarily affected neuronal discharge rates and the degree of neuronal synchronization. In contrast, local changes in the magnitude of stick-slip events affected the transformation of these kinematic and kinetic characteristics into neuronal discharges. Most cortical neurons exhibited surface coarseness selectivity through global and local stick-slip event properties. However, this selectivity varied across coding strategies in the same neurons, given that each coding strategy reflected different aspects of changes in whisker-surface interactions. The degree of spatial similarity in surface coarseness preference in adjacently recorded neurons differed among these coding strategies. Adjacently recorded neurons exhibited the same surface coarseness preference in their firing rates but not through other coding strategies. Through these results, we were able to show that local stick-slip event properties contribute to texture discrimination, complementing and surpassing global coding in this context. These findings suggest that the representation of surface coarseness in the cortex may rely on concurrent coding strategies that integrate tactile information across different spatiotemporal scales.
Collapse
Affiliation(s)
| | - Rony Azouz
- Department of Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Be'er Sheva, Southern District, Israel
| |
Collapse
|
5
|
Stachniak TJ, Argunsah AÖ, Yang JW, Cai L, Karayannis T. Presynaptic Kainate Receptors onto Somatostatin Interneurons Are Recruited by Activity throughout Development and Contribute to Cortical Sensory Adaptation. J Neurosci 2023; 43:7101-7118. [PMID: 37709538 PMCID: PMC10601374 DOI: 10.1523/jneurosci.1461-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/24/2023] [Accepted: 08/30/2023] [Indexed: 09/16/2023] Open
Abstract
Somatostatin (SST) interneurons produce delayed inhibition because of the short-term facilitation of their excitatory inputs created by the expression of metabotropic glutamate receptor 7 (mGluR7) and presynaptic GluK2-containing kainate receptors (GluK2-KARs). Using mice of both sexes, we find that as synaptic facilitation at layer (L)2/3 SST cell inputs increases during the first few postnatal weeks, so does GluK2-KAR expression. Removal of sensory input by whisker trimming does not affect mGluR7 but prevents the emergence of presynaptic GluK2-KARs, which can be restored by allowing whisker regrowth or by acute calmodulin activation. Conversely, late trimming or acute inhibition of Ca2+/calmodulin-dependent protein kinase II is sufficient to reduce GluK2-KAR activity. This developmental and activity-dependent regulation also produces a specific reduction of L4 GluK2-KARs that advances in parallel with the maturation of sensory processing in L2/3. Finally, we find that removal of both GluK2-KARs and mGluR7 from the synapse eliminates short-term facilitation and reduces sensory adaptation to repetitive stimuli, first in L4 of somatosensory cortex, then later in development in L2/3. The dynamic regulation of presynaptic GluK2-KARs potentially allows for flexible scaling of late inhibition and sensory adaptation.SIGNIFICANCE STATEMENT Excitatory synapses onto somatostatin (SST) interneurons express presynaptic, calcium-permeable kainate receptors containing the GluK2 subunit (GluK2-KARs), activated by high-frequency activity. In this study we find that their presence on L2/3 SST synapses in the barrel cortex is not based on a hardwired genetic program but instead is regulated by sensory activity, in contrast to that of mGluR7. Thus, in addition to standard synaptic potentiation and depression mechanisms, excitatory synapses onto SST neurons undergo an activity-dependent presynaptic modulation that uses GluK2-KARs. Further, we present evidence that loss of the frequency-dependent synaptic components (both GluK2-KARs and mGluR7 via Elfn1 deletion) contributes to a decrease in the sensory adaptation commonly seen on repetitive stimulus presentation.
Collapse
Affiliation(s)
- Tevye J Stachniak
- Laboratory of Neural Circuit Assembly, Brain Research Institute, Neuroscience Center Zurich, University of Zurich, CH-8057 Zurich, Switzerland
| | - Ali Ö Argunsah
- Laboratory of Neural Circuit Assembly, Brain Research Institute, Neuroscience Center Zurich, University of Zurich, CH-8057 Zurich, Switzerland
| | - Jenq-Wei Yang
- Laboratory of Neural Circuit Assembly, Brain Research Institute, Neuroscience Center Zurich, University of Zurich, CH-8057 Zurich, Switzerland
| | - Linbi Cai
- Laboratory of Neural Circuit Assembly, Brain Research Institute, Neuroscience Center Zurich, University of Zurich, CH-8057 Zurich, Switzerland
| | - Theofanis Karayannis
- Laboratory of Neural Circuit Assembly, Brain Research Institute, Neuroscience Center Zurich, University of Zurich, CH-8057 Zurich, Switzerland
| |
Collapse
|
6
|
Klavinskis-Whiting S, Bitzenhofer S, Hanganu-Opatz I, Ellender T. Generation and propagation of bursts of activity in the developing basal ganglia. Cereb Cortex 2023; 33:10595-10613. [PMID: 37615347 PMCID: PMC10560579 DOI: 10.1093/cercor/bhad307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/25/2023] Open
Abstract
The neonatal brain is characterized by intermittent bursts of oscillatory activity interspersed by relative silence. Although well-characterized for many cortical areas, to what extent these propagate and interact with subcortical brain areas is largely unknown. Here, early network activity was recorded from the developing basal ganglia, including motor/somatosensory cortex, dorsal striatum, and intralaminar thalamus, during the first postnatal weeks in mice. An unsupervised detection and classification method revealed two main classes of bursting activity, namely spindle bursts and nested gamma spindle bursts, characterized by oscillatory activity at ~ 10 and ~ 30 Hz frequencies, respectively. These were reliably identified across all three brain regions and exhibited region-specific differences in their structural, spectral, and developmental characteristics. Bursts of the same type often co-occurred in different brain regions and coherence and cross-correlation analyses reveal dynamic developmental changes in their interactions. The strongest interactions were seen for cortex and striatum, from the first postnatal week onwards, and cortex appeared to drive burst events in subcortical regions. Together, these results provide the first detailed description of early network activity within the developing basal ganglia and suggest that cortex is one of the main drivers of activity in downstream nuclei during this postnatal period.
Collapse
Affiliation(s)
| | - Sebastian Bitzenhofer
- Department of Biomedical Sciences, Institute of Developmental Neurophysiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Ileana Hanganu-Opatz
- Department of Biomedical Sciences, Institute of Developmental Neurophysiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Tommas Ellender
- Department of Pharmacology, University of Oxford, Mansfield Rd, Oxford, OX13QT, United Kingdom
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| |
Collapse
|
7
|
Lombardi A, Wang Q, Stüttgen MC, Mittmann T, Luhmann HJ, Kilb W. Recovery kinetics of short-term depression of GABAergic and glutamatergic synapses at layer 2/3 pyramidal cells in the mouse barrel cortex. Front Cell Neurosci 2023; 17:1254776. [PMID: 37817883 PMCID: PMC10560857 DOI: 10.3389/fncel.2023.1254776] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 09/11/2023] [Indexed: 10/12/2023] Open
Abstract
Introduction Short-term synaptic plasticity (STP) is a widespread mechanism underlying activity-dependent modifications of cortical networks. Methods To investigate how STP influences excitatory and inhibitory synapses in layer 2/3 of mouse barrel cortex, we combined whole-cell patch-clamp recordings from visually identified pyramidal neurons (PyrN) and parvalbumin-positive interneurons (PV-IN) of cortical layer 2/3 in acute slices with electrical stimulation of afferent fibers in layer 4 and optogenetic activation of PV-IN. Results These experiments revealed that electrical burst stimulation (10 pulses at 10 Hz) of layer 4 afferents to layer 2/3 neurons induced comparable short-term depression (STD) of glutamatergic postsynaptic currents (PSCs) in PyrN and in PV-IN, while disynaptic GABAergic PSCs in PyrN showed a stronger depression. Burst-induced depression of glutamatergic PSCs decayed within <4 s, while the decay of GABAergic PSCs required >11 s. Optogenetically-induced GABAergic PSCs in PyrN also demonstrated STD after burst stimulation, with a decay of >11 s. Excitatory postsynaptic potentials (EPSPs) in PyrN were unaffected after electrical burst stimulation, while a selective optogenetic STD of GABAergic synapses caused a transient increase of electrically evoked EPSPs in PyrN. Discussion In summary, these results demonstrate substantial short-term plasticity at all synapses investigated and suggest that the prominent STD observed in GABAergic synapses can moderate the functional efficacy of glutamatergic STD after repetitive synaptic stimulations. This mechanism may contribute to a reliable information flow toward the integrative layer 2/3 for complex time-varying sensory stimuli.
Collapse
Affiliation(s)
- Aniello Lombardi
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Qiang Wang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Maik C. Stüttgen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Thomas Mittmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Heiko J. Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| |
Collapse
|
8
|
Vandevelde JR, Yang JW, Albrecht S, Lam H, Kaufmann P, Luhmann HJ, Stüttgen MC. Layer- and cell-type-specific differences in neural activity in mouse barrel cortex during a whisker detection task. Cereb Cortex 2023; 33:1361-1382. [PMID: 35417918 DOI: 10.1093/cercor/bhac141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 11/14/2022] Open
Abstract
To address the question which neocortical layers and cell types are important for the perception of a sensory stimulus, we performed multielectrode recordings in the barrel cortex of head-fixed mice performing a single-whisker go/no-go detection task with vibrotactile stimuli of differing intensities. We found that behavioral detection probability decreased gradually over the course of each session, which was well explained by a signal detection theory-based model that posits stable psychometric sensitivity and a variable decision criterion updated after each reinforcement, reflecting decreasing motivation. Analysis of multiunit activity demonstrated highest neurometric sensitivity in layer 4, which was achieved within only 30 ms after stimulus onset. At the level of single neurons, we observed substantial heterogeneity of neurometric sensitivity within and across layers, ranging from nonresponsiveness to approaching or even exceeding psychometric sensitivity. In all cortical layers, putative inhibitory interneurons on average proffered higher neurometric sensitivity than putative excitatory neurons. In infragranular layers, neurons increasing firing rate in response to stimulation featured higher sensitivities than neurons decreasing firing rate. Offline machine-learning-based analysis of videos of behavioral sessions showed that mice performed better when not moving, which at the neuronal level, was reflected by increased stimulus-evoked firing rates.
Collapse
Affiliation(s)
- Jens R Vandevelde
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany.,Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Steffen Albrecht
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Henry Lam
- Computational Intelligence, Faculty of Law, Management and Economics, Johannes Gutenberg University Mainz, Jakob-Welder-Weg 9, 55128 Mainz, Germany
| | - Paul Kaufmann
- Computational Intelligence, Faculty of Law, Management and Economics, Johannes Gutenberg University Mainz, Jakob-Welder-Weg 9, 55128 Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Maik C Stüttgen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| |
Collapse
|
9
|
Yeganeh F, Knauer B, Guimarães Backhaus R, Yang JW, Stroh A, Luhmann HJ, Stüttgen MC. Effects of optogenetic inhibition of a small fraction of parvalbumin-positive interneurons on the representation of sensory stimuli in mouse barrel cortex. Sci Rep 2022; 12:19419. [PMID: 36371511 PMCID: PMC9653449 DOI: 10.1038/s41598-022-24156-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 11/10/2022] [Indexed: 11/13/2022] Open
Abstract
Inhibitory interneurons play central roles in the modulation of spontaneous network activity and in processing of neuronal information. In sensory neocortical areas, parvalbumin-positive (PV+) GABAergic interneurons control the representation and processing of peripheral sensory inputs. We studied the functional role of PV+ interneurons in the barrel cortex of anesthetized adult PVCre mice by combining extracellular multi-electrode recordings with optogenetic silencing of a small fraction of PV+ interneurons. In all cortical layers, optogenetic inhibition caused an increase in spontaneous network activity from theta to gamma frequencies. The spatio-temporal representation of sensory inputs was studied by stimulating one or two whiskers at different intervals and analyzing the resulting local field potential (LFP) and single unit (SU) response. Silencing PV+ interneurons caused an increase in LFP response to sensory stimulation and a decrease in temporal discrimination of consecutive whisker deflections. The combined effect of whisker deflection and optogenetic inhibition was highly similar to the linear sum of the individual effects of these two manipulations. SU recordings revealed that optogenetic silencing reduced stimulus detectability by increasing stimulus-evoked firing rate by a constant offset, suggesting that PV+ interneurons improve signal-to-noise ratio by reducing ongoing spiking activity, thereby sharpening the spatio-temporal representation of sensory stimuli.
Collapse
Affiliation(s)
- Fahimeh Yeganeh
- grid.410607.4Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany ,grid.410607.4Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Beate Knauer
- grid.410607.4Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | | | - Jenq-Wei Yang
- grid.410607.4Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Albrecht Stroh
- grid.410607.4Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany ,grid.509458.50000 0004 8087 0005Leibniz Institute for Resilience Research, Mainz, Germany
| | - Heiko J. Luhmann
- grid.410607.4Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Maik C. Stüttgen
- grid.410607.4Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| |
Collapse
|
10
|
Cai L, Yang JW, Wang CF, Chou SJ, Luhmann HJ, Karayannis T. Identification of a Developmental Switch in Information Transfer between Whisker S1 and S2 Cortex in Mice. J Neurosci 2022; 42:4435-4448. [PMID: 35501157 PMCID: PMC9172289 DOI: 10.1523/jneurosci.2246-21.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 04/13/2022] [Accepted: 04/19/2022] [Indexed: 12/03/2022] Open
Abstract
The whiskers of rodents are a key sensory organ that provides critical tactile information for animal navigation and object exploration throughout life. Previous work has explored the developmental sensory-driven activation of the primary sensory cortex processing whisker information (wS1), also called barrel cortex. This body of work has shown that the barrel cortex is already activated by sensory stimuli during the first postnatal week. However, it is currently unknown when over the course of development these stimuli begin being processed by higher-order cortical areas, such as secondary whisker somatosensory area (wS2). Here we investigate the developmental engagement of wS2 by whisker stimuli and the emergence of corticocortical communication from wS1 to wS2. Using in vivo wide-field imaging and multielectrode recordings in control and conditional KO mice of either sex with thalamocortical innervation defects, we find that wS1 and wS2 are able to process bottom-up information coming from the thalamus from birth. We also identify that it is only at the end of the first postnatal week that wS1 begins to provide functional excitation into wS2, switching to more inhibitory actions after the second postnatal week. Therefore, we have uncovered a developmental window when information transfer between wS1 and wS2 reaches mature function.SIGNIFICANCE STATEMENT At the end of the first postnatal week, the primary whisker somatosensory area starts providing excitatory input to the secondary whisker somatosensory area 2. This excitatory drive weakens during the second postnatal week and switches to inhibition in the adult.
Collapse
Affiliation(s)
- Linbi Cai
- Laboratory of Neural Circuit Assembly, Brain Research Institute, University of Zürich, CH-8057, Zürich, Switzerland
| | - Jenq-Wei Yang
- Laboratory of Neural Circuit Assembly, Brain Research Institute, University of Zürich, CH-8057, Zürich, Switzerland
- Institute of Physiology, University Medical Center, Johannes Gutenberg University Mainz, 55128, Mainz, Germany
| | - Chia-Fang Wang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Shen-Ju Chou
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center, Johannes Gutenberg University Mainz, 55128, Mainz, Germany
| | - Theofanis Karayannis
- Laboratory of Neural Circuit Assembly, Brain Research Institute, University of Zürich, CH-8057, Zürich, Switzerland
| |
Collapse
|
11
|
Non-ablative doses of focal ionizing radiation alters function of central neural circuits. Brain Stimul 2022; 15:586-597. [PMID: 35395424 DOI: 10.1016/j.brs.2022.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/22/2022] [Accepted: 04/01/2022] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Modulation of pathological neural circuit activity in the brain with a minimum of complications is an area of intense interest. OBJECTIVE The goal of the study was to alter neurons' physiological states without apparent damage of cellular integrity using stereotactic radiosurgery (SRS). METHODS We treated a 7.5 mm-diameter target on the visual cortex of Göttingen minipigs with doses of 40, 60, 80, and 100 Gy. Six months post-irradiation, the pigs were implanted with a 9 mm-wide, eight-shank multi-electrode probe, which spanned the radiation focus as well as the low-exposure neighboring areas. RESULTS Doses of 40 Gy led to an increase of spontaneous firing rate, six months post-irradiation, while doses of 60 Gy and greater were associated with a decrease. Subjecting the animals to visual stimuli resulted in typical visual evoked potentials (VEP). At 40 Gy, a significant reduction of the P1 peak time, indicative of higher network excitability was observed. At 80 Gy, P1 peak time was not affected, while a minor reduction at 60 Gy was seen. No distance-dependent effects on spontaneous firing rate, or on VEP were observed. Post-mortem histology revealed no evidence of necrosis at doses below 60 Gy. In an in vitro assay comprising of iPS-derived human neuron-astrocyte co-cultures, we found a higher vulnerability of inhibitory neurons than excitatory neurons with respect to radiation, which might provide the cellular mechanism of the disinhibitory effect observed in vivo. CONCLUSION We provide initial evidence for a rather circuit-wide, long-lasting disinhibitory effect of low sub-ablative doses of SRS.
Collapse
|
12
|
Isbister JB, Reyes-Puerta V, Sun JJ, Horenko I, Luhmann HJ. Clustering and control for adaptation uncovers time-warped spike time patterns in cortical networks in vivo. Sci Rep 2021; 11:15066. [PMID: 34326363 PMCID: PMC8322153 DOI: 10.1038/s41598-021-94002-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 06/29/2021] [Indexed: 12/04/2022] Open
Abstract
How information in the nervous system is encoded by patterns of action potentials (i.e. spikes) remains an open question. Multi-neuron patterns of single spikes are a prime candidate for spike time encoding but their temporal variability requires further characterisation. Here we show how known sources of spike count variability affect stimulus-evoked spike time patterns between neurons separated over multiple layers and columns of adult rat somatosensory cortex in vivo. On subsets of trials (clusters) and after controlling for stimulus-response adaptation, spike time differences between pairs of neurons are “time-warped” (compressed/stretched) by trial-to-trial changes in shared excitability, explaining why fixed spike time patterns and noise correlations are seldom reported. We show that predicted cortical state is correlated between groups of 4 neurons, introducing the possibility of spike time pattern modulation by population-wide trial-to-trial changes in excitability (i.e. cortical state). Under the assumption of state-dependent coding, we propose an improved potential encoding capacity.
Collapse
Affiliation(s)
- James B Isbister
- Oxford Centre for Theoretical Neuroscience and Artificial Intelligence, Department of Experimental Psychology, University of Oxford, Oxford, UK. .,The Blue Brain Project, École Polytechnique Fédérale de Lausanne, 1202, Geneva, Switzerland.
| | - Vicente Reyes-Puerta
- Institute of Physiology, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| | - Jyh-Jang Sun
- Institute of Physiology, University Medical Center, Johannes Gutenberg University, Mainz, Germany.,NERF, Kapeldreef 75, 3001, Leuven, Belgium.,imec, Remisebosweg 1, 3001, Leuven, Belgium
| | - Illia Horenko
- Faculty of Informatics, Universita della Svizzera Italiana, Via G. Buffi 13, 6900, Lugano, Switzerland
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| |
Collapse
|
13
|
Sugashi T, Yuki H, Niizawa T, Takuwa H, Kanno I, Masamoto K. Three-dimensional microvascular network reconstruction from in vivo images with adaptation of the regional inhomogeneity in the signal-to-noise ratio. Microcirculation 2021; 28:e12697. [PMID: 33786951 DOI: 10.1111/micc.12697] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/19/2021] [Accepted: 03/22/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Quantification of angiographic images with two-photon laser scanning fluorescence microscopy (2PLSM) relies on proper segmentation of the vascular images. However, the images contain inhomogeneities in the signal-to-noise ratio (SNR) arising from regional effects of light scattering and absorption. The present study developed a semiautomated quantification method for volume images of 2PLSM angiography by adjusting the binarization threshold according to local SNR along the vessel centerlines. METHODS A phantom model made with fluorescent microbeads was used to incorporate a region-dependent binarization threshold. RESULTS The recommended SNR for imaging was found to be 4.2-10.6 that provide the true size of imaged objects if the binarization threshold was fixed at 50% of SNR. However, angiographic images in the mouse cortex showed variable SNR up to 45 over the depths. To minimize the errors caused by variable SNR and a spatial extent of the imaged objects in an axial direction, the microvascular networks were three-dimensionally reconstructed based on the cross-sectional diameters measured along the vessel centerline from the XY-plane images with adapted binarization threshold. The arterial volume was relatively constant over depths of 0-500 µm, and the capillary volume (1.7% relative to the scanned volume) showed the larger volumes than the artery (0.8%) and vein (0.6%). CONCLUSIONS The present methods allow consistent segmentation of microvasculature by adapting the local inhomogeneity in the SNR, which will be useful for quantitative comparison of the microvascular networks, such as under disease conditions where SNR in the 2PLSM images varies over space and time.
Collapse
Affiliation(s)
- Takuma Sugashi
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
| | - Hiroya Yuki
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
| | - Tomoya Niizawa
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
| | - Hiroyuki Takuwa
- Functional Brain Imaging Research, National Institute of Radiological Sciences, Chiba, Japan
| | - Iwao Kanno
- Functional Brain Imaging Research, National Institute of Radiological Sciences, Chiba, Japan
| | - Kazuto Masamoto
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan.,Functional Brain Imaging Research, National Institute of Radiological Sciences, Chiba, Japan.,Center for Neuroscience and Biomedical Engineering, University of Electro-Communications, Chofu, Japan
| |
Collapse
|
14
|
Juárez-Vidales JDJ, Pérez-Ortega J, Lorea-Hernández JJ, Méndez-Salcido F, Peña-Ortega F. Configuration and dynamics of dominant inspiratory multineuronal activity patterns during eupnea and gasping generation in vitro. J Neurophysiol 2021; 125:1289-1306. [PMID: 33502956 DOI: 10.1152/jn.00563.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The pre-Bötzinger complex (preBötC), located within the ventral respiratory column, produces inspiratory bursts in varying degrees of synchronization/amplitude. This wide range of population burst patterns reflects the flexibility of the preBötC neurons, which is expressed in variations in the onset/offset times of their activations and their activity during the population bursts, with respiratory neurons exhibiting a large cycle-to-cycle timing jitter both at the population activity onset and at the population activity peak, suggesting that respiratory neurons are stochastically activated before and during the inspiratory bursts. However, it is still unknown whether this stochasticity is maintained while evaluating the coactivity of respiratory neuronal ensembles. Moreover, the preBötC topology also remains unknown. In this study, by simultaneously recording tens of preBötC neurons and using coactivation analysis during the inspiratory periods, we found that the preBötC has a scale-free configuration (mixture of not many highly connected nodes, hubs, with abundant poorly connected elements) exhibiting the rich-club phenomenon (hubs more likely interconnected with each other). PreBötC neurons also produce multineuronal activity patterns (MAPs) that are highly stable and change during the hypoxia-induced reconfiguration. Moreover, preBötC contains a coactivating core network shared by all its MAPs. Finally, we found a distinctive pattern of sequential coactivation of core network neurons at the beginning of the inspiratory periods, indicating that, when evaluated at the multicellular level, the coactivation of respiratory neurons seems not to be stochastic.NEW & NOTEWORTHY By means of multielectrode recordings of preBötC neurons, we evaluated their configuration in normoxia and hypoxia, finding that the preBötC exhibits a scale-free configuration with a rich-club phenomenon. preBötC neurons produce multineuronal activity patterns that are highly stable but change during hypoxia. The preBötC contains a coactivating core network that exhibit a distinctive pattern of coactivation at the beginning of inspirations. These results reveal some network basis of inspiratory rhythm generation and its reconfiguration during hypoxia.
Collapse
Affiliation(s)
- Josué de Jesús Juárez-Vidales
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Queretaro, Mexico
| | - Jesús Pérez-Ortega
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Queretaro, Mexico
| | - Jonathan Julio Lorea-Hernández
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Queretaro, Mexico
| | - Felipe Méndez-Salcido
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Queretaro, Mexico
| | - Fernando Peña-Ortega
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Queretaro, Mexico
| |
Collapse
|
15
|
Dikecligil GN, Graham DM, Park IM, Fontanini A. Layer- and Cell Type-Specific Response Properties of Gustatory Cortex Neurons in Awake Mice. J Neurosci 2020; 40:9676-9691. [PMID: 33172981 PMCID: PMC7726536 DOI: 10.1523/jneurosci.1579-19.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 02/27/2020] [Accepted: 10/24/2020] [Indexed: 01/07/2023] Open
Abstract
Studies in visual, auditory, and somatosensory cortices have revealed that different cell types as well as neurons located in different laminae display distinct stimulus response profiles. The extent to which these layer and cell type-specific distinctions generalize to gustatory cortex (GC) remains unknown. In this study, we performed extracellular recordings in adult female mice to monitor the activity of putative pyramidal and inhibitory neurons located in deep and superficial layers of GC. Awake, head-restrained mice were trained to lick different tastants (sucrose, salt, citric acid, quinine, and water) from a lick spout. We found that deep layer neurons show higher baseline firing rates (FRs) in GC with deep-layer inhibitory neurons displaying highest FRs at baseline and following the stimulus. GC's activity shows robust modulations before animals' contact with tastants, and this phenomenon is most prevalent in deep-layer inhibitory neurons. Furthermore, we show that licking activity strongly shapes the spiking pattern of GC pyramidal neurons, eliciting phase-locked spiking across trials and tastants. We demonstrate that there is a greater percentage of taste-coding neurons in deep versus superficial layers with chemosensitive neurons across all categories showing similar breadth of tuning, but different decoding performance. Lastly, we provide evidence for functional convergence in GC, with neurons that can show prestimulus activity, licking-related rhythmicity and taste responses. Overall, our results demonstrate that baseline and stimulus-evoked firing profiles of GC neurons and their processing schemes change as a function of cortical layer and cell type in awake mice.SIGNIFICANCE STATEMENT Sensory cortical areas show a laminar structure, with each layer composed of distinct cell types embedded in different circuits. While studies in other primary sensory areas have elucidated that pyramidal and inhibitory neurons belonging to distinct layers show distinct response properties, whether and how response properties of gustatory cortex (GC) neurons change as a function of their laminar position and cell type remains uninvestigated. Here, we show that there are several notable differences in baseline, prestimulus, and stimulus-evoked response profiles of pyramidal and inhibitory neurons belonging to deep and superficial layers of GC.
Collapse
Affiliation(s)
- Gulce Nazli Dikecligil
- Department of Neurobiology and Behavior and Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, New York 11794
| | - Dustin M Graham
- Department of Neurobiology and Behavior and Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, New York 11794
| | - Il Memming Park
- Department of Neurobiology and Behavior and Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, New York 11794
| | - Alfredo Fontanini
- Department of Neurobiology and Behavior and Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, New York 11794
| |
Collapse
|
16
|
Staiger JF, Petersen CCH. Neuronal Circuits in Barrel Cortex for Whisker Sensory Perception. Physiol Rev 2020; 101:353-415. [PMID: 32816652 DOI: 10.1152/physrev.00019.2019] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The array of whiskers on the snout provides rodents with tactile sensory information relating to the size, shape and texture of objects in their immediate environment. Rodents can use their whiskers to detect stimuli, distinguish textures, locate objects and navigate. Important aspects of whisker sensation are thought to result from neuronal computations in the whisker somatosensory cortex (wS1). Each whisker is individually represented in the somatotopic map of wS1 by an anatomical unit named a 'barrel' (hence also called barrel cortex). This allows precise investigation of sensory processing in the context of a well-defined map. Here, we first review the signaling pathways from the whiskers to wS1, and then discuss current understanding of the various types of excitatory and inhibitory neurons present within wS1. Different classes of cells can be defined according to anatomical, electrophysiological and molecular features. The synaptic connectivity of neurons within local wS1 microcircuits, as well as their long-range interactions and the impact of neuromodulators, are beginning to be understood. Recent technological progress has allowed cell-type-specific connectivity to be related to cell-type-specific activity during whisker-related behaviors. An important goal for future research is to obtain a causal and mechanistic understanding of how selected aspects of tactile sensory information are processed by specific types of neurons in the synaptically connected neuronal networks of wS1 and signaled to downstream brain areas, thus contributing to sensory-guided decision-making.
Collapse
Affiliation(s)
- Jochen F Staiger
- University Medical Center Göttingen, Institute for Neuroanatomy, Göttingen, Germany; and Laboratory of Sensory Processing, Faculty of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Carl C H Petersen
- University Medical Center Göttingen, Institute for Neuroanatomy, Göttingen, Germany; and Laboratory of Sensory Processing, Faculty of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| |
Collapse
|
17
|
Burkhanova G, Chernova K, Khazipov R, Sheroziya M. Effects of Cortical Cooling on Activity Across Layers of the Rat Barrel Cortex. Front Syst Neurosci 2020; 14:52. [PMID: 32848644 PMCID: PMC7417609 DOI: 10.3389/fnsys.2020.00052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/06/2020] [Indexed: 12/25/2022] Open
Abstract
Moderate cortical cooling is known to suppress slow oscillations and to evoke persistent cortical activity. However, the cooling-induced changes in electrical activity across cortical layers remain largely unknown. Here, we performed multi-channel local field potential (LFP) and multi-unit activity (MUA) recordings with linear silicone probes through the layers of single cortical barrel columns in urethane-anesthetized rats under normothermia (38°C) and during local cortical surface cooling (30°C). During cortically generated slow oscillations, moderate cortical cooling decreased delta wave amplitude, delta-wave occurrence, the duration of silent states, and delta wave-locked MUA synchronization. Moderate cortical cooling increased total time spent in the active state and decreased total time spent in the silent state. Cooling-evoked changes in the MUA firing rate in cortical layer 5 (L5) varied from increase to decrease across animals, and the polarity of changes in L5 MUA correlated with changes in total time spent in the active state. The decrease in temperature reduced MUA firing rates in all other cortical layers. Sensory-evoked MUA responses also decreased during cooling through all cortical layers. The cooling-dependent slowdown was detected at the fast time-scale with a decreased frequency of sensory-evoked high-frequency oscillations (HFO). Thus, moderate cortical cooling suppresses slow oscillations and desynchronizes neuronal activity through all cortical layers, and is associated with reduced firing across all cortical layers except L5, where cooling induces variable and non-consistent changes in neuronal firing, which are common features of the transition from slow-wave synchronization to desynchronized activity in the barrel cortex.
Collapse
Affiliation(s)
| | - Kseniya Chernova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Aix Marseille University, INSERM, INMED, Marseille, France
| | - Maxim Sheroziya
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| |
Collapse
|
18
|
Kang S, Hayashi Y, Bruyns-Haylett M, Delivopoulos E, Zheng Y. Model-Predicted Balance Between Neural Excitation and Inhibition Was Maintained Despite of Age-Related Decline in Sensory Evoked Local Field Potential in Rat Barrel Cortex. Front Syst Neurosci 2020; 14:24. [PMID: 32528256 PMCID: PMC7247833 DOI: 10.3389/fnsys.2020.00024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 04/08/2020] [Indexed: 11/25/2022] Open
Abstract
The balance between neural excitation and inhibition has been shown to be crucial for normal brain function. However, it is unclear whether this balance is maintained through healthy aging. This study investigated the effect of aging on the temporal dynamics of the somatosensory evoked local field potential (LFP) in rats and tested the hypothesis that excitatory and inhibitory post-synaptic activities remain balanced during the aging process. The LFP signal was obtained from the barrel cortex of three different age groups of anesthetized rats (pre-adolescence: 4–6 weeks, young adult: 2–3 months, middle-aged adult: 10–20 months) under whisker pad stimulation. To confirm our previous finding that the initial segment of the evoked LFP was solely associated with excitatory post-synaptic activity, we micro-injected gabazine into the barrel cortex to block inhibition while LFP was collected continuously under the same stimulus condition. As expected, the initial slope of the evoked LFP in the granular layer was unaffected by gabazine injection. We subsequently estimated the excitatory and inhibitory post-synaptic activities through a balanced model of the LFP with delayed inhibition as an explicit constraint, and calculated the amplitude ratio of inhibition to excitation. We found an age-dependent slowing of the temporal dynamics in the somatosensory-evoked post-synaptic activity, as well as a significant age-related decrease in the amplitude of the excitatory component and a decreasing trend in the amplitude of the inhibitory component. Furthermore, the delay of inhibition with respect to excitation was significantly increased with age, but the amplitude ratio was maintained. Our findings suggest that aging reduces the amplitude of neural responses, but the balance between sensory evoked excitatory and inhibitory post-synaptic activities is maintained to support normal brain function during healthy aging. Further whole cell patch clamp experiments will be needed to confirm or refute these findings by measuring sensory evoked synaptic excitatory and inhibitory activities in vivo during the normal aging process.
Collapse
Affiliation(s)
- Sungmin Kang
- Biomedical Engineering, School of Biological Sciences, University of Reading, Reading, United Kingdom.,Centre for Integrative Neuroscience and Neurodynamics (CINN), University of Reading, Reading, United Kingdom
| | - Yurie Hayashi
- Biomedical Engineering, School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Michael Bruyns-Haylett
- Department of Bioengineering, Imperial College, South Kensington Campus, London, United Kingdom
| | - Evangelos Delivopoulos
- Biomedical Engineering, School of Biological Sciences, University of Reading, Reading, United Kingdom.,Centre for Integrative Neuroscience and Neurodynamics (CINN), University of Reading, Reading, United Kingdom
| | - Ying Zheng
- Biomedical Engineering, School of Biological Sciences, University of Reading, Reading, United Kingdom.,Centre for Integrative Neuroscience and Neurodynamics (CINN), University of Reading, Reading, United Kingdom
| |
Collapse
|
19
|
Vecchia D, Beltramo R, Vallone F, Chéreau R, Forli A, Molano-Mazón M, Bawa T, Binini N, Moretti C, Holtmaat A, Panzeri S, Fellin T. Temporal Sharpening of Sensory Responses by Layer V in the Mouse Primary Somatosensory Cortex. Curr Biol 2020; 30:1589-1599.e10. [PMID: 32169206 PMCID: PMC7198976 DOI: 10.1016/j.cub.2020.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 01/16/2020] [Accepted: 02/03/2020] [Indexed: 01/14/2023]
Abstract
The timing of stimulus-evoked spikes encodes information about sensory stimuli. Here we studied the neural circuits controlling this process in the mouse primary somatosensory cortex. We found that brief optogenetic activation of layer V pyramidal cells just after whisker deflection modulated the membrane potential of neurons and interrupted their long-latency whisker responses, increasing their accuracy in encoding whisker deflection time. In contrast, optogenetic inhibition of layer V during either passive whisker deflection or active whisking decreased accuracy in encoding stimulus or touch time, respectively. Suppression of layer V pyramidal cells increased reaction times in a texture discrimination task. Moreover, two-color optogenetic experiments revealed that cortical inhibition was efficiently recruited by layer V stimulation and that it mainly involved activation of parvalbumin-positive rather than somatostatin-positive interneurons. Layer V thus performs behaviorally relevant temporal sharpening of sensory responses through circuit-specific recruitment of cortical inhibition.
Collapse
Affiliation(s)
- Dania Vecchia
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, 16163 Genova, Italy; Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy
| | - Riccardo Beltramo
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Fabio Vallone
- Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy
| | - Ronan Chéreau
- Department of Basic Neurosciences, Geneva University Neurocenter, Faculty of Medicine, University of Geneva, 1206 Geneva, Switzerland
| | - Angelo Forli
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, 16163 Genova, Italy; Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy
| | - Manuel Molano-Mazón
- Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy; Neural Computation Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy
| | - Tanika Bawa
- Department of Basic Neurosciences, Geneva University Neurocenter, Faculty of Medicine, University of Geneva, 1206 Geneva, Switzerland
| | - Noemi Binini
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, 16163 Genova, Italy; Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy
| | - Claudio Moretti
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, 16163 Genova, Italy; Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy
| | - Anthony Holtmaat
- Department of Basic Neurosciences, Geneva University Neurocenter, Faculty of Medicine, University of Geneva, 1206 Geneva, Switzerland
| | - Stefano Panzeri
- Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy; Neural Computation Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, 38068 Rovereto, Italy
| | - Tommaso Fellin
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, 16163 Genova, Italy; Neural Coding Laboratory, Istituto Italiano di Tecnologia, 16163 Genova and 38068 Rovereto, Italy.
| |
Collapse
|
20
|
Wickham J, Corna A, Schwarz N, Uysal B, Layer N, Honegger JB, Wuttke TV, Koch H, Zeck G. Human Cerebrospinal Fluid Induces Neuronal Excitability Changes in Resected Human Neocortical and Hippocampal Brain Slices. Front Neurosci 2020; 14:283. [PMID: 32372899 PMCID: PMC7186381 DOI: 10.3389/fnins.2020.00283] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/12/2020] [Indexed: 12/22/2022] Open
Abstract
Human cerebrospinal fluid (hCSF) has proven advantageous over conventional medium for culturing both rodent and human brain tissue. In addition, increased activity and synchrony, closer to the dynamic states exclusively recorded in vivo, were reported in rodent slices and cell cultures switching from artificial cerebrospinal fluid (aCSF) to hCSF. This indicates that hCSF possesses properties that are not matched by the aCSF, which is generally used for most electrophysiological recordings. To evaluate the possible significance of using hCSF as an electrophysiological recording medium, also for human brain tissue, we compared the network and single-cell firing properties of human brain slice cultures during perfusion with hCSF and aCSF. For measuring the overall activity from a majority of neurons within neocortical and hippocampal human slices, we used a microelectrode array (MEA) recording technique with 252 electrodes covering an area of 3.2 × 3.2 mm2. A second CMOS-based MEA with 4225 sensors on a 2 × 2 mm2 area was used for detailed mapping of action potential waveforms and cell identification. We found that hCSF increased the number of active electrodes and neurons and the firing rate of the neurons in the slices and induced an increase in the numbers of single channel and population bursts. Interestingly, not only an increase in the overall activity in the slices was observed, but a reconfiguration of the network could also be detected with specific activation and inactivation of subpopulations of neuronal ensembles. In conclusion, hCSF is an important component to consider for future human brain slice studies, especially for experiments designed to mimic parts of physiology and disease observed in vivo.
Collapse
Affiliation(s)
- Jenny Wickham
- Neurophysics, Natural and Medical Sciences Institute, University of Tübingen, Reutlingen, Germany
| | - Andrea Corna
- Neurophysics, Natural and Medical Sciences Institute, University of Tübingen, Reutlingen, Germany
- Graduate School of Neural Information Processing/International Max Planck Research School, Tübingen, Germany
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Niklas Schwarz
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Betül Uysal
- Graduate School of Neural Information Processing/International Max Planck Research School, Tübingen, Germany
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Nikolas Layer
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | | | - Thomas V. Wuttke
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Neurosurgery, University of Tübingen, Tübingen, Germany
| | - Henner Koch
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Epileptology, Neurology, RWTH Aachen University, Aachen, Germany
| | - Günther Zeck
- Neurophysics, Natural and Medical Sciences Institute, University of Tübingen, Reutlingen, Germany
| |
Collapse
|
21
|
Nolte M, Gal E, Markram H, Reimann MW. Impact of higher order network structure on emergent cortical activity. Netw Neurosci 2020; 4:292-314. [PMID: 32181420 PMCID: PMC7069066 DOI: 10.1162/netn_a_00124] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 12/23/2019] [Indexed: 11/04/2022] Open
Abstract
Synaptic connectivity between neocortical neurons is highly structured. The network structure of synaptic connectivity includes first-order properties that can be described by pairwise statistics, such as strengths of connections between different neuron types and distance-dependent connectivity, and higher order properties, such as an abundance of cliques of all-to-all connected neurons. The relative impact of first- and higher order structure on emergent cortical network activity is unknown. Here, we compare network structure and emergent activity in two neocortical microcircuit models with different synaptic connectivity. Both models have a similar first-order structure, but only one model includes higher order structure arising from morphological diversity within neuronal types. We find that such morphological diversity leads to more heterogeneous degree distributions, increases the number of cliques, and contributes to a small-world topology. The increase in higher order network structure is accompanied by more nuanced changes in neuronal firing patterns, such as an increased dependence of pairwise correlations on the positions of neurons in cliques. Our study shows that circuit models with very similar first-order structure of synaptic connectivity can have a drastically different higher order network structure, and suggests that the higher order structure imposed by morphological diversity within neuronal types has an impact on emergent cortical activity.
Collapse
Affiliation(s)
- Max Nolte
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Eyal Gal
- Edmond and Lily Safra Center for Brain Sciences, The Hebrew University, Jerusalem, Israel
- Department of Neurobiology, The Hebrew University, Jerusalem, Israel
| | - Henry Markram
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Laboratory of Neural Microcircuitry, Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Michael W. Reimann
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| |
Collapse
|
22
|
van der Meij J, Martinez-Gonzalez D, Beckers GJL, Rattenborg NC. Intra-"cortical" activity during avian non-REM and REM sleep: variant and invariant traits between birds and mammals. Sleep 2019; 42:5195213. [PMID: 30462347 DOI: 10.1093/sleep/zsy230] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 11/19/2018] [Indexed: 01/23/2023] Open
Abstract
Several mammalian-based theories propose that the varying patterns of neuronal activity occurring in wakefulness and sleep reflect different modes of information processing. Neocortical slow-waves, hippocampal sharp-wave ripples, and thalamocortical spindles occurring during mammalian non-rapid eye-movement (NREM) sleep are proposed to play a role in systems-level memory consolidation. Birds show similar NREM and REM (rapid eye-movement) sleep stages to mammals; however, it is unclear whether all neurophysiological rhythms implicated in mammalian memory consolidation are also present. Moreover, it is unknown whether the propagation of slow-waves described in the mammalian neocortex occurs in the avian "cortex" during natural NREM sleep. We used a 32-channel silicon probe connected to a transmitter to make intracerebral recordings of the visual hyperpallium and thalamus in naturally sleeping pigeons (Columba livia). As in the mammalian neocortex, slow-waves during NREM sleep propagated through the hyperpallium. Propagation primarily occurred in the thalamic input layers of the hyperpallium, regions that also showed the greatest slow-wave activity (SWA). Spindles were not detected in both the visual hyperpallium, including regions receiving thalamic input, and thalamus, using a recording method that readily detects spindles in mammals. Interestingly, during REM sleep fast gamma bursts in the hyperpallium (when present) were restricted to the thalamic input layers. In addition, unlike mice, the decrease in SWA from NREM to REM sleep was the greatest in these layers. Taken together, these variant and invariant neurophysiological aspects of avian and mammalian sleep suggest that there may be associated mechanistic and functional similarities and differences between avian and mammalian sleep.
Collapse
Affiliation(s)
- Jacqueline van der Meij
- Avian Sleep Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, Seewiesen, Germany
| | - Dolores Martinez-Gonzalez
- Avian Sleep Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, Seewiesen, Germany
| | - Gabriël J L Beckers
- Cognitive Neurobiology and Helmholtz Institute, Utrecht University, Yalelaan, CM Utrecht, The Netherlands
| | - Niels C Rattenborg
- Avian Sleep Group, Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, Seewiesen, Germany
| |
Collapse
|
23
|
Egger R, Narayanan RT, Guest JM, Bast A, Udvary D, Messore LF, Das S, de Kock CPJ, Oberlaender M. Cortical Output Is Gated by Horizontally Projecting Neurons in the Deep Layers. Neuron 2019; 105:122-137.e8. [PMID: 31784285 PMCID: PMC6953434 DOI: 10.1016/j.neuron.2019.10.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 09/01/2019] [Accepted: 10/02/2019] [Indexed: 12/13/2022]
Abstract
Pyramidal tract neurons (PTs) represent the major output cell type of the mammalian neocortex. Here, we report the origins of the PTs’ ability to respond to a broad range of stimuli with onset latencies that rival or even precede those of their intracortical input neurons. We find that neurons with extensive horizontally projecting axons cluster around the deep-layer terminal fields of primary thalamocortical axons. The strategic location of these corticocortical neurons results in high convergence of thalamocortical inputs, which drive reliable sensory-evoked responses that precede those in other excitatory cell types. The resultant fast and horizontal stream of excitation provides PTs throughout the cortical area with input that acts to amplify additional inputs from thalamocortical and other intracortical populations. The fast onsets and broadly tuned characteristics of PT responses hence reflect a gating mechanism in the deep layers, which assures that sensory-evoked input can be reliably transformed into cortical output. Simulations predict in vivo responses for major output cell type of the neocortex Simulations reveal strategy how to test the origins of cortical output empirically Manipulations confirm that deep-layer corticocortical neurons gate cortical output Gating of cortical output originates from deep-layer thalamocortical input stratum
Collapse
Affiliation(s)
- Robert Egger
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Rajeevan T Narayanan
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Jason M Guest
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Arco Bast
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Daniel Udvary
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Luis F Messore
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Suman Das
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU Amsterdam, De Boelelaan 1085, 1081 Amsterdam, the Netherlands
| | - Christiaan P J de Kock
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU Amsterdam, De Boelelaan 1085, 1081 Amsterdam, the Netherlands
| | - Marcel Oberlaender
- Max Planck Research Group In Silico Brain Sciences, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany.
| |
Collapse
|
24
|
Zakharov A, Chernova K, Burkhanova G, Holmes GL, Khazipov R. Segregation of seizures and spreading depolarization across cortical layers. Epilepsia 2019; 60:2386-2397. [PMID: 31755112 DOI: 10.1111/epi.16390] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 10/25/2019] [Accepted: 10/25/2019] [Indexed: 01/13/2023]
Abstract
OBJECTIVE Cortical spreading depolarization (SD) and seizures are often co-occurring electrophysiological phenomena. However, the cross-layer dynamics of SD during seizures and the effect of SD on epileptic activity across cortical layers remain largely unknown. METHODS We explored the spatial-temporal dynamics of SD and epileptic activity across layers of the rat barrel cortex using direct current silicone probe recordings during flurothyl-induced seizures. RESULTS SD occurred in half of the flurothyl-evoked seizures. SD always started from the superficial layers and spread downward either through all cortical layers or stopping at the L4/L5 border. In cases without SD, seizures were characterized by synchronized population firing across all cortical layers throughout the entire seizure. However, when SD occurred, epileptic activity was transiently silenced in layers involved with SD but persisted in deeper layers. During partial SD, epileptiform activity persisted in deep layers throughout the entire seizure, with positive signals at the cortical surface reflecting passive sources of population spikes generated in deeper cortical layers. During full SD, the initial phase of SD propagation through the superficial layers was similar to partial SD, with suppression of activity at the superficial layers and segregation of seizures to deep layers. Further propagation of SD to deep layers resulted in a wave of transient suppression of epileptic activity through the entire cortical column. Thus, vertical propagation of SD through the cortical column creates dynamic network states during which epileptiform activity is restricted to layers without SD. SIGNIFICANCE Our results point to the importance of vertical SD spread in the SD-related depression of epileptiform activity across cortical layers.
Collapse
Affiliation(s)
- Andrey Zakharov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Department of physiology, Kazan State Medical University, Kazan, Russia
| | - Kseniya Chernova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | | | - Gregory L Holmes
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Mediterranean Institute of Neurobiology, National Institute of Health and Medical Research Mixed Unit of Research 1249, Aix-Marseille University, Marseille, France
| |
Collapse
|
25
|
Rodriguez-Moreno J, Rollenhagen A, Arlandis J, Santuy A, Merchan-Pérez A, DeFelipe J, Lübke JHR, Clasca F. Quantitative 3D Ultrastructure of Thalamocortical Synapses from the "Lemniscal" Ventral Posteromedial Nucleus in Mouse Barrel Cortex. Cereb Cortex 2019; 28:3159-3175. [PMID: 28968773 PMCID: PMC6946031 DOI: 10.1093/cercor/bhx187] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 07/03/2017] [Indexed: 01/20/2023] Open
Abstract
Thalamocortical synapses from “lemniscal” neurons of the dorsomedial portion of the rodent ventral posteromedial nucleus (VPMdm) are able to induce with remarkable efficacy, despite their relative low numbers, the firing of primary somatosensory cortex (S1) layer 4 (L4) neurons. To which extent this high efficacy depends on structural synaptic features remains unclear. Using both serial transmission (TEM) and focused ion beam milling scanning electron microscopy (FIB/SEM), we 3D-reconstructed and quantitatively analyzed anterogradely labeled VPMdm axons in L4 of adult mouse S1. All VPMdm synapses are asymmetric. Virtually all are established by axonal boutons, 53% of which contact multiple (2–4) elements (overall synapse/bouton ratio = 1.6). Most boutons are large (mean 0.47 μm3), and contain 1–3 mitochondria. Vesicle pools and postsynaptic density (PSD) surface areas are large compared to others in rodent cortex. Most PSDs are complex. Most synapses (83%) are established on dendritic spine heads. Furthermore, 15% of the postsynaptic spines receive a second, symmetric synapse. In addition, 13% of the spine heads have a large protrusion inserted into a membrane pouch of the VPMdm bouton. The unusual combination of structural features in VPMdm synapses is likely to contribute significantly to the high efficacy, strength, and plasticity of these thalamocortical synapses.
Collapse
Affiliation(s)
- Javier Rodriguez-Moreno
- Department of Anatomy & Neuroscience, School of Medicine, Autonoma de Madrid University, Madrid, Spain
| | - Astrid Rollenhagen
- Institute of Neuroscience and Medicine INM-2, Research Centre Jülich GmbH, Jülich, Germany
| | - Jaime Arlandis
- Department of Anatomy & Neuroscience, School of Medicine, Autonoma de Madrid University, Madrid, Spain
| | - Andrea Santuy
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid, Spain.,CIBERNED, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, Madrid, Spain
| | - Angel Merchan-Pérez
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid, Spain.,CIBERNED, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, Madrid, Spain.,Departamento de Arquitectura y Tecnología de Sistemas Informáticos, Universidad Politécnica de Madrid, Boadilla del Monte, Madrid, Spain
| | - Javier DeFelipe
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid, Spain.,CIBERNED, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, Madrid, Spain.,Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Joachim H R Lübke
- Institute of Neuroscience and Medicine INM-2, Research Centre Jülich GmbH, Jülich, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Aachen, Germany.,JARA-Brain Medicine, Aachen, Germany
| | - Francisco Clasca
- Department of Anatomy & Neuroscience, School of Medicine, Autonoma de Madrid University, Madrid, Spain
| |
Collapse
|
26
|
Slow-Wave Activity in the S1HL Cortex Is Contributed by Different Layer-Specific Field Potential Sources during Development. J Neurosci 2019; 39:8900-8915. [PMID: 31548234 PMCID: PMC6832678 DOI: 10.1523/jneurosci.1212-19.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 08/06/2019] [Accepted: 08/27/2019] [Indexed: 01/12/2023] Open
Abstract
Spontaneous correlated activity in cortical columns is critical for postnatal circuit refinement. We used spatial discrimination techniques to explore the late maturation of synaptic pathways through the laminar distribution of the field potential (FP) generators underlying spontaneous and evoked activities of the S1HL cortex in juvenile (P14-P16) and adult anesthetized rats. Juveniles exhibit an intermittent FP pattern resembling Up/Down states in adults, but with much reduced power and different laminar distribution. Whereas FPs in active periods are dominated by a layer VI generator in juveniles, in adults a developing multipart generator takes over, displaying current sinks in middle layers (III-V). The blockade of excitatory transmission in upper and middle layers of adults recovered the juvenile-like FP profiles. In addition to the layer VI generator, a gamma-specific generator in supragranular layers was the same in both age groups. While searching for dynamical coupling among generators in juveniles we found significant cross-correlation in ∼one-half of the tested pairs, whereas excessive coherence hindered their efficient separation in adults. Also, potentials evoked by tactile and electrical stimuli showed different short-latency dipoles between the two age groups, and the juveniles lacked the characteristic long latency UP state currents in middle layers. In addition, the mean firing rate of neurons was lower in juveniles. Thus, cortical FPs originate from different intra-columnar segments as they become active postnatally. We suggest that although some cortical segments are active early postnatally, a functional sensory-motor control relies on a delayed maturation and network integration of synaptic connections in middle layers.SIGNIFICANCE STATEMENT Early postnatal activity in the rodent cortex is mostly endogenous, whereas it becomes driven by peripheral input at later stages. The precise schedule for the maturation of synaptic pathways is largely unknown. We explored this in the somatosensory hindlimb cortex at an age when animals begin to use their limbs by uncovering the laminar distribution of the field potential generators underlying the dominant delta waves in juveniles and adults. Our results suggest that field potentials are mostly generated by a pathway in deep layers, whereas other pathways mature later in middle layers and take over in adults. We suggest that a functional sensory-motor control relies on a delayed maturation and network integration of synaptic connections in middle layers.
Collapse
|
27
|
Lebedeva J, Zakharov A, Burkhanova G, Chernova K, Khazipov R. The Effects of NMDA Receptor Blockade on Sensory-Evoked Responses in Superficial Layers of the Rat Barrel Cortex. Front Cell Neurosci 2019; 13:259. [PMID: 31231195 PMCID: PMC6567857 DOI: 10.3389/fncel.2019.00259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 05/23/2019] [Indexed: 01/22/2023] Open
Abstract
Transmission of excitation from L4 to L2/3 is a part of a canonical circuit of cortical sensory signal processing. While synapses from L4 to L2/3 are mediated by both AMPA and NMDA glutamate receptors, previous studies suggested that sensory-evoked excitation of neurons in supragranular layers is almost entirely mediated by NMDA receptors. Here, we readdressed this question using extracellular recordings of sensory-evoked potentials (SEPs) and multiple unit activity (MUA) in the rat barrel cortex. We found that blockade of NMDA receptors using the selective antagonist dAPV profoundly inhibited the late part of L2/3 SEP, the associated sink, and MUA response but did not affect its initial part. Our results indicate that both non-NMDA and NMDA receptors are involved in sensory signal transmission from L4 to L2/3. While non-NMDA receptors mediate fast transmission of sensory signals, NMDA-Rs are importantly involved in the generation of the late phase of the sensory-evoked response in supragranular layers.
Collapse
Affiliation(s)
- Julia Lebedeva
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | - Andrey Zakharov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Department of Physiology, Kazan State Medical University, Kazan, Russia
| | | | - Kseniya Chernova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Aix Marseille University, INSERM, INMED, Marseille, France
| |
Collapse
|
28
|
Rattenborg NC, van der Meij J, Beckers GJL, Lesku JA. Local Aspects of Avian Non-REM and REM Sleep. Front Neurosci 2019; 13:567. [PMID: 31231182 PMCID: PMC6560081 DOI: 10.3389/fnins.2019.00567] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 05/17/2019] [Indexed: 12/12/2022] Open
Abstract
Birds exhibit two types of sleep that are in many respects similar to mammalian rapid eye movement (REM) and non-REM (NREM) sleep. As in mammals, several aspects of avian sleep can occur in a local manner within the brain. Electrophysiological evidence of NREM sleep occurring more deeply in one hemisphere, or only in one hemisphere – the latter being a phenomenon most pronounced in dolphins – was actually first described in birds. Such asymmetric or unihemispheric NREM sleep occurs with one eye open, enabling birds to visually monitor their environment for predators. Frigatebirds primarily engage in this form of sleep in flight, perhaps to avoid collisions with other birds. In addition to interhemispheric differences in NREM sleep intensity, the intensity of NREM sleep is homeostatically regulated in a local, use-depended manner within each hemisphere. Furthermore, the intensity and temporo-spatial distribution of NREM sleep-related slow waves varies across layers of the avian hyperpallium – a primary visual area – with the slow waves occurring first in, and propagating through and outward from, thalamic input layers. Slow waves also have the greatest amplitude in these layers. Although most research has focused on NREM sleep, there are also local aspects to avian REM sleep. REM sleep-related reductions in skeletal muscle tone appear largely restricted to muscles involved in maintaining head posture. Other local aspects of sleep manifest as a mixture of features of NREM and REM sleep occurring simultaneously in different parts of the neuroaxis. Like monotreme mammals, ostriches often exhibit brainstem-mediated features of REM sleep (muscle atonia and REMs) while the hyperpallium shows EEG slow waves typical of NREM sleep. Finally, although mice show slow waves in thalamic input layers of primary sensory cortices during REM sleep, this is not the case in the hyperpallium of pigeons, suggesting that this phenomenon is not a universal feature of REM sleep. Collectively, the local aspects of sleep described in birds and mammals reveal that wakefulness, NREM sleep, and REM sleep are not always discrete states.
Collapse
Affiliation(s)
- Niels C Rattenborg
- Avian Sleep Group, Max Planck Institute for Ornithology, Seewiesen, Germany
| | | | - Gabriël J L Beckers
- Cognitive Neurobiology and Helmholtz Institute, Utrecht University, Utrecht, Netherlands
| | - John A Lesku
- School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| |
Collapse
|
29
|
State-aware detection of sensory stimuli in the cortex of the awake mouse. PLoS Comput Biol 2019; 15:e1006716. [PMID: 31150385 PMCID: PMC6561583 DOI: 10.1371/journal.pcbi.1006716] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 06/12/2019] [Accepted: 05/15/2019] [Indexed: 11/19/2022] Open
Abstract
Cortical responses to sensory inputs vary across repeated presentations of identical stimuli, but how this trial-to-trial variability impacts detection of sensory inputs is not fully understood. Using multi-channel local field potential (LFP) recordings in primary somatosensory cortex (S1) of the awake mouse, we optimized a data-driven cortical state classifier to predict single-trial sensory-evoked responses, based on features of the spontaneous, ongoing LFP recorded across cortical layers. Our findings show that, by utilizing an ongoing prediction of the sensory response generated by this state classifier, an ideal observer improves overall detection accuracy and generates robust detection of sensory inputs across various states of ongoing cortical activity in the awake brain, which could have implications for variability in the performance of detection tasks across brain states. Establishing the link between neural activity and behavior is a central goal of neuroscience. One context in which to examine this link is in a sensory detection task, in which an animal is trained to report the presence of a barely perceptible sensory stimulus. In such tasks, both sensory responses in the brain and behavioral responses are highly variable. A simple hypothesis, originating in signal detection theory, is that perceived inputs generate neural activity that cross some threshold for detection. According to this hypothesis, sensory response variability would predict behavioral variability, but previous studies have not born out this prediction. Further complicating the picture, sensory response variability is partially dependent on the ongoing state of cortical activity, and we wondered whether this could resolve the mismatch between response variability and behavioral variability. Here, we use a computational approach to study an adaptive observer that utilizes an ongoing prediction of sensory responsiveness to detect sensory inputs. This observer has higher overall accuracy than the standard ideal observer. Moreover, because of the adaptation, the observer breaks the direct link between neural and behavioral variability, which could resolve discrepancies arising in past studies. We suggest new experiments to test our theory.
Collapse
|
30
|
van der Bourg A, Yang JW, Stüttgen MC, Reyes-Puerta V, Helmchen F, Luhmann HJ. Temporal refinement of sensory-evoked activity across layers in developing mouse barrel cortex. Eur J Neurosci 2019; 50:2955-2969. [PMID: 30941846 DOI: 10.1111/ejn.14413] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 03/05/2019] [Accepted: 03/17/2019] [Indexed: 12/22/2022]
Abstract
Rhythmic whisking behavior in rodents fully develops during a critical period about 2 weeks after birth, in parallel with the maturation of other sensory modalities and the onset of exploratory locomotion. How whisker-related sensory processing develops during this period in the primary somatosensory cortex (S1) remains poorly understood. Here, we characterized neuronal activity evoked by single- or dual-whisker stimulation patterns in developing S1, before, during and after the occurrence of active whisking. Employing multi-electrode recordings in all layers of barrel cortex in urethane-anesthetized mice, we find layer-specific changes in multi-unit activity for principal and neighboring barrel columns. While whisker stimulation evoked similar early responses (0-50 ms post-stimulus) across development, the late response (50-150 ms post-stimulus) decreased in all layers with age. Furthermore, peak onset times and the duration of the late response decreased in all layers across age groups. Responses to paired-pulse stimulation showed increases in spiking precision and in paired-pulse ratios in all cortical layers during development. Sequential activation of two neighboring whiskers with varying stimulus intervals evoked distinct response profiles in the activated barrel columns, depending on the direction and temporal separation of the stimuli. In conclusion, our findings indicate that the temporal sharpening of sensory-evoked activity coincides with the onset of active whisking.
Collapse
Affiliation(s)
- Alexander van der Bourg
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, Zurich, Switzerland
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Maik C Stüttgen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Vicente Reyes-Puerta
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Fritjof Helmchen
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, Zurich, Switzerland
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| |
Collapse
|
31
|
van der Meij J, Martinez-Gonzalez D, Beckers GJL, Rattenborg NC. Neurophysiology of Avian Sleep: Comparing Natural Sleep and Isoflurane Anesthesia. Front Neurosci 2019; 13:262. [PMID: 30983954 PMCID: PMC6447711 DOI: 10.3389/fnins.2019.00262] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 03/06/2019] [Indexed: 11/21/2022] Open
Abstract
Propagating slow-waves in electroencephalogram (EEG) or local field potential (LFP) recordings occur during non-rapid eye-movement (NREM) sleep in both mammals and birds. Moreover, in both, input from the thalamus is thought to contribute to the genesis of NREM sleep slow-waves. Interestingly, the general features of slow-waves are also found under isoflurane anesthesia. However, it is unclear to what extent these slow-waves reflect the same processes as those giving rise to NREM sleep slow-waves. Similar slow-wave spatio-temporal properties during NREM sleep and isoflurane anesthesia would suggest that both types of slow-waves are based on related processes. We used a 32-channel silicon probe connected to a transmitter to make intra-cortical recordings of the visual hyperpallium in naturally sleeping and isoflurane anesthetized pigeons (Columba livia) using a within-bird design. Under anesthesia, the amplitude of LFP slow-waves was higher when compared to NREM sleep. Spectral power density across all frequencies (1.5–100 Hz) was also elevated. In addition, slow-wave coherence between electrode sites was higher under anesthesia, indicating higher synchrony when compared to NREM sleep. Nonetheless, the spatial distribution of slow-waves under anesthesia was more comparable to NREM sleep than to wake or REM sleep. Similar to NREM sleep, slow-wave propagation under anesthesia mainly occurred in the thalamic input layers of the hyperpallium, regions which also showed the greatest slow-wave power during both recording conditions. This suggests that the thalamus could be involved in the genesis of slow-waves under both conditions. Taken together, although slow-waves under isoflurane anesthesia are stronger, they share spatio-temporal activity characteristics with slow-waves during NREM sleep.
Collapse
Affiliation(s)
| | | | - Gabriël J L Beckers
- Cognitive Neurobiology and Helmholtz Institute, Utrecht University, Utrecht, Netherlands
| | - Niels C Rattenborg
- Avian Sleep Group, Max Planck Institute for Ornithology, Seewiesen, Germany
| |
Collapse
|
32
|
Senzai Y, Fernandez-Ruiz A, Buzsáki G. Layer-Specific Physiological Features and Interlaminar Interactions in the Primary Visual Cortex of the Mouse. Neuron 2019; 101:500-513.e5. [PMID: 30635232 PMCID: PMC6367010 DOI: 10.1016/j.neuron.2018.12.009] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/27/2018] [Accepted: 12/04/2018] [Indexed: 12/01/2022]
Abstract
The relationship between mesoscopic local field potentials (LFPs) and single-neuron firing in the multi-layered neocortex is poorly understood. Simultaneous recordings from all layers in the primary visual cortex (V1) of the behaving mouse revealed functionally defined layers in V1. The depth of maximum spike power and sink-source distributions of LFPs provided consistent laminar landmarks across animals. Coherence of gamma oscillations (30-100 Hz) and spike-LFP coupling identified six physiological layers and further sublayers. Firing rates, burstiness, and other electrophysiological features of neurons displayed unique layer and brain state dependence. Spike transmission strength from layer 2/3 cells to layer 5 pyramidal cells and interneurons was stronger during waking compared with non-REM sleep but stronger during non-REM sleep among deep-layer excitatory neurons. A subset of deep-layer neurons was active exclusively in the DOWN state of non-REM sleep. These results bridge mesoscopic LFPs and single-neuron interactions with laminar structure in V1.
Collapse
Affiliation(s)
- Yuta Senzai
- Neuroscience Institute, New York University, Langone Medical Center, New York, NY 10016, USA
| | - Antonio Fernandez-Ruiz
- Neuroscience Institute, New York University, Langone Medical Center, New York, NY 10016, USA
| | - György Buzsáki
- Neuroscience Institute, New York University, Langone Medical Center, New York, NY 10016, USA; Department of Neurology, Langone Medical Center, New York University, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA.
| |
Collapse
|
33
|
Superficial Layers Suppress the Deep Layers to Fine-tune Cortical Coding. J Neurosci 2019; 39:2052-2064. [PMID: 30651326 DOI: 10.1523/jneurosci.1459-18.2018] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 12/17/2018] [Accepted: 12/20/2018] [Indexed: 11/21/2022] Open
Abstract
The descending microcircuit from layer 2/3 (L2/3) to layer 5 (L5) is one of the strongest excitatory pathways in the cortex, presumably forming a core component of its feedforward hierarchy. To date, however, no experiments have selectively tested the impact of L2/3 activity on L5 during active sensation. We used optogenetic, cell-type-specific manipulation of L2/3 neurons in the barrel cortex of actively sensing mice (of either sex) to elucidate the significance of this pathway to sensory coding in L5. Contrary to standard models, activating L2/3 predominantly suppressed spontaneous activity in L5, whereas deactivating L2/3 mainly facilitated touch responses in L5. Somatostatin interneurons are likely important to this suppression because their optogenetic deactivation significantly altered the functional impact of L2/3 onto L5. The net effect of L2/3 was to enhance the stimulus selectivity and expand the range of L5 output. These data imply that the core cortical pathway increases the selectivity and expands the range of cortical output through feedforward inhibition.SIGNIFICANCE STATEMENT The primary sensory cortex contains six distinct layers that interact to form the basis of our perception. While rudimentary patterns of connectivity between the layers have been outlined quite extensively in vitro, functional relationships in vivo, particularly during active sensation, remain poorly understood. We used cell-type-specific optogenetics to test the functional relationship between layer 2/3 and layer 5. Surprisingly, we discovered that L2/3 primarily suppresses cortical output from L5. The recruitment of somatostatin-positive interneurons is likely fundamental to this relationship. The net effect of this translaminar suppression is to enhance the selectivity and expand the range of receptive fields, therefore potentially sharpening the perception of space.
Collapse
|
34
|
Studer F, Laghouati E, Jarre G, David O, Pouyatos B, Depaulis A. Sensory coding is impaired in rat absence epilepsy. J Physiol 2019; 597:951-966. [PMID: 30548850 DOI: 10.1113/jp277297] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 12/12/2018] [Indexed: 01/16/2023] Open
Abstract
KEY POINTS Absence epilepsy is characterized by the occurrence of spike-and-wave discharges concomitant with an alteration of consciousness and is associated with cognitive comorbidities. In a genetic model of absence epilepsy in the rat, the genetic absence epilepsy rat from Strasbourg (GAERS), spike-and-wave discharges are shown to be initiated in the barrel field primary somatosensory cortex that codes whisker-related information, therefore playing an essential role in the interactions of rodents with their environment. Sensory-information processing is impaired in the epileptic barrel field primary somatosensory cortex of GAERS, with a delayed sensory-evoked potential and a duplicated neuronal response to whisker stimulation in in vivo extracellular recordings. Yet, GAERS present no defaults of performance in a texture discrimination task, suggesting the existence of a compensatory mechanism within the epileptic neuronal network. The results of the present study indicate that physiological primary functions are processed differently in an epileptic cortical network. ABSTRACT Several neurodevelopmental pathologies are associated with disorganized cortical circuits that may alter primary functions such as sensory processes. In the present study, we investigated whether the function of a cortical area is altered in the seizure onset zone of absence epilepsy, a prototypical form of childhood genetic epilepsy associated with cognitive impairments. We first combined in vivo multichannel electrophysiological recordings and histology to precisely localize the seizure onset zone in the genetic absence epilepsy rat from Strasbourg (GAERS). We then investigated the functionality of this epileptic zone using extracellular silicon probe recordings of sensory-evoked local field potentials and multi-unit activity, as well as a behavioural test of texture discrimination. We show that seizures in this model are initiated in the barrel field part of the primary somatosensory cortex and are associated with high-frequency oscillations. In this cortex, we found an increased density of parvalbumin-expressing interneurons in layer 5 in GAERS compared to non-epileptic Wistar rats. Its functional investigation revealed that sensory abilities of GAERS are not affected in a texture-discrimination task, whereas the intracortical processing of sensory-evoked information is delayed and duplicated. Altogether, these results suggest that absence seizures are associated with an increase of parvalbumin-inhibitory neurons, which may promote the functional relationship between epileptic oscillations and high-frequency activities. Our findings suggest that cortical circuits operate differently in the epileptic onset zone and may adapt to maintain their ability to process highly specialized information.
Collapse
Affiliation(s)
- Florian Studer
- University Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France.,Inserm, U1216, Grenoble, France
| | - Emel Laghouati
- University Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France.,Inserm, U1216, Grenoble, France
| | - Guillaume Jarre
- University Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France.,Inserm, U1216, Grenoble, France
| | - Olivier David
- University Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France.,Inserm, U1216, Grenoble, France
| | - Benoît Pouyatos
- University Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France.,Inserm, U1216, Grenoble, France.,Present address: INRS, F-54519, Vandoeuvre Les Nancy, France
| | - Antoine Depaulis
- University Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France.,Inserm, U1216, Grenoble, France
| |
Collapse
|
35
|
Vinokurova D, Zakharov AV, Lebedeva J, Burkhanova GF, Chernova KA, Lotfullina N, Khazipov R, Valeeva G. Pharmacodynamics of the Glutamate Receptor Antagonists in the Rat Barrel Cortex. Front Pharmacol 2018; 9:698. [PMID: 30018551 PMCID: PMC6038834 DOI: 10.3389/fphar.2018.00698] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 06/08/2018] [Indexed: 02/01/2023] Open
Abstract
Epipial application is one of the approaches for drug delivery into the cortex. However, passive diffusion of epipially applied drugs through the cortical depth may be slow, and different drug concentrations may be achieved at different rates across the cortical depth. Here, we explored the pharmacodynamics of the inhibitory effects of epipially applied ionotropic glutamate receptor antagonists CNQX and dAPV on sensory-evoked and spontaneous activity across layers of the cortical barrel column in urethane-anesthetized rats. The inhibitory effects of CNQX and dAPV were observed at concentrations that were an order higher than in slices in vitro, and they slowly developed from the cortical surface to depth after epipial application. The level of the inhibitory effects also followed the surface-to-depth gradient, with full inhibition of sensory evoked potentials (SEPs) in the supragranular layers and L4 and only partial inhibition in L5 and L6. During epipial CNQX and dAPV application, spontaneous activity and the late component of multiple unit activity (MUA) during sensory-evoked responses were suppressed faster than the short-latency MUA component. Despite complete suppression of SEPs in L4, sensory-evoked short-latency multiunit responses in L4 persisted, and they were suppressed by further addition of lidocaine suggesting that spikes in thalamocortical axons contribute ∼20% to early multiunit responses. Epipial CNQX and dAPV also completely suppressed sensory-evoked very fast (∼500 Hz) oscillations and spontaneous slow wave activity in L2/3 and L4. However, delta oscillations persisted in L5/6. Thus, CNQX and dAPV exert inhibitory actions on cortical activity during epipial application at much higher concentrations than in vitro, and the pharmacodynamics of their inhibitory effects is characterized by the surface-to-depth gradients in the rate of development and the level of inhibition of sensory-evoked and spontaneous cortical activity.
Collapse
Affiliation(s)
- Daria Vinokurova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Mediterranean Institute of Neurobiology - National Institute of Health and Medical Research, Aix-Marseille University, UMR1249, Marseille, France
| | | | - Julia Lebedeva
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | | | | | - Nailya Lotfullina
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Mediterranean Institute of Neurobiology - National Institute of Health and Medical Research, Aix-Marseille University, UMR1249, Marseille, France
| | - Rustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,Mediterranean Institute of Neurobiology - National Institute of Health and Medical Research, Aix-Marseille University, UMR1249, Marseille, France
| | - Guzel Valeeva
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| |
Collapse
|
36
|
Yang JW, Prouvot PH, Reyes-Puerta V, Stüttgen MC, Stroh A, Luhmann HJ. Optogenetic Modulation of a Minor Fraction of Parvalbumin-Positive Interneurons Specifically Affects Spatiotemporal Dynamics of Spontaneous and Sensory-Evoked Activity in Mouse Somatosensory Cortex in Vivo. Cereb Cortex 2018; 27:5784-5803. [PMID: 29040472 PMCID: PMC5939210 DOI: 10.1093/cercor/bhx261] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Parvalbumin (PV) positive interneurons exert strong effects on the neocortical excitatory network, but it remains unclear how they impact the spatiotemporal dynamics of sensory processing in the somatosensory cortex. Here, we characterized the effects of optogenetic inhibition and activation of PV interneurons on spontaneous and sensory-evoked activity in mouse barrel cortex in vivo. Inhibiting PV interneurons led to a broad-spectrum power increase both in spontaneous and sensory-evoked activity. Whisker-evoked responses were significantly increased within 20 ms after stimulus onset during inhibition of PV interneurons, demonstrating high temporal precision of PV-shaped inhibition. Multiunit activity was strongly enhanced in neighboring cortical columns, but not at the site of transduction, supporting a central and highly specific role of PV interneurons in lateral inhibition. Inversely, activating PV interneurons drastically decreased spontaneous and whisker-evoked activity in the principal column and exerted strong lateral inhibition. Histological assessment of transduced cells combined with quantitative modeling of light distribution and spike sorting revealed that only a minor fraction (~10%) of the local PV population comprising no more than a few hundred neurons is optogenetically modulated, mediating the observed prominent and widespread effects on neocortical processing.
Collapse
Affiliation(s)
- Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Pierre-Hugues Prouvot
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany.,Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Vicente Reyes-Puerta
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Maik C Stüttgen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Albrecht Stroh
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany.,Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| |
Collapse
|
37
|
van der Bourg A, Yang JW, Reyes-Puerta V, Laurenczy B, Wieckhorst M, Stüttgen MC, Luhmann HJ, Helmchen F. Layer-Specific Refinement of Sensory Coding in Developing Mouse Barrel Cortex. Cereb Cortex 2018; 27:4835-4850. [PMID: 27620976 DOI: 10.1093/cercor/bhw280] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 08/17/2016] [Indexed: 12/20/2022] Open
Abstract
Rodent rhythmic whisking behavior matures during a critical period around 2 weeks after birth. The functional adaptations of neocortical circuitry during this developmental period remain poorly understood. Here, we characterized stimulus-evoked neuronal activity across all layers of mouse barrel cortex before, during, and after the onset of whisking behavior. Employing multi-electrode recordings and 2-photon calcium imaging in anesthetized mice, we tested responses to rostro-caudal whisker deflections, axial "tapping" stimuli, and their combination from postnatal day 10 (P10) to P28. Within this period, whisker-evoked activity of neurons displayed a general decrease in layer 2/3 (L2/3) and L4, but increased in L5 and L6. Distinct alterations in neuronal response adaptation during the 2-s period of stimulation at ~5 Hz accompanied these changes. Moreover, single-unit analysis revealed that response selectivity in favor of either lateral deflection or axial tapping emerges in deeper layers within the critical period around P14. For superficial layers we confirmed this finding using calcium imaging of L2/3 neurons, which also exhibited emergence of response selectivity as well as progressive sparsification and decorrelation of evoked responses around P14. Our results demonstrate layer-specific development of sensory responsiveness and response selectivity in mouse somatosensory cortex coinciding with the onset of exploratory behavior.
Collapse
Affiliation(s)
- Alexander van der Bourg
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, CH-8057 Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, D-55128 Mainz, Germany
| | - Vicente Reyes-Puerta
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, D-55128 Mainz, Germany
| | - Balazs Laurenczy
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, CH-8057 Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland
| | - Martin Wieckhorst
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, CH-8057 Zurich, Switzerland
| | - Maik C Stüttgen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University, D-55128 Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, D-55128 Mainz, Germany
| | - Fritjof Helmchen
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, CH-8057 Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, CH-8057 Zurich, Switzerland
| |
Collapse
|
38
|
Hama N, Kawai M, Ito SI, Hirota A. Optical study of interactions among propagation waves of neural excitation in the rat somatosensory cortex evoked by forelimb and hindlimb stimuli. J Neurophysiol 2018; 119:1934-1946. [DOI: 10.1152/jn.00904.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Multisite optical recording has revealed that the neural excitation wave induced by a sensory stimulation begins at a focus and propagates in the cortex. This wave is considered to be important for computation in the sensory cortex, particularly the integration of sensory information; however, the nature of this wave remains largely unknown. In the present study, we examined the interaction between two waves in the rat sensory cortex induced by hindlimb and forelimb stimuli with different interstimulus intervals. We classified the resultant patterns as follows: 1) the collision of two waves, 2) the hindlimb response being evoked while the forelimb-induced wave is passing the hindlimb focus, and 3) the hindlimb response being evoked after the forelimb-induced wave has passed the hindlimb focus. In pattern 1, the two waves fused into a single wave, but the propagation pattern differed from that predicted by the superimposition of two singly induced propagation courses. In pattern 2, the state of the interaction between the two waves varied depending on the phase of optical signals constituting the forelimb-induced wave around the hindlimb focus. Although no hindlimb-induced wave was observed in the rising phase, the propagating velocity of the forelimb-induced wave increased. At the peak, neither the hindlimb-induced response nor a modulatory effect on the forelimb-induced wave was detected. In pattern 3, the hindlimb-induced wave showed a reduced amplitude and spatial extent. These results indicate that the state of the interaction between waves was strongly influenced by the relative timing of sensory inputs. NEW & NOTEWORTHY Sensory stimulation-induced cortical excitation propagates as a wave and spreads over a wide area of the sensory cortex. To elucidate the characteristics of this relatively unknown phenomenon, we examined the interaction between two individually induced waves in the somatosensory cortex. Either the waves collided or the preceding wave affected the emergence of the following one. Our results indicate that the state of the interaction was strongly influenced by the relative timing of sensory inputs.
Collapse
Affiliation(s)
- Noriyuki Hama
- Department of Neural and Muscular Physiology, Shimane University School of Medicine, Izumo, Shimane, Japan
| | - Minako Kawai
- Department of Neural and Muscular Physiology, Shimane University School of Medicine, Izumo, Shimane, Japan
| | - Shin-Ichi Ito
- Department of Neural and Muscular Physiology, Shimane University School of Medicine, Izumo, Shimane, Japan
| | - Akihiko Hirota
- Department of Neural and Muscular Physiology, Shimane University School of Medicine, Izumo, Shimane, Japan
| |
Collapse
|
39
|
Vogt J, Kirischuk S, Unichenko P, Schlüter L, Pelosi A, Endle H, Yang JW, Schmarowski N, Cheng J, Thalman C, Strauss U, Prokudin A, Bharati BS, Aoki J, Chun J, Lutz B, Luhmann HJ, Nitsch R. Synaptic Phospholipid Signaling Modulates Axon Outgrowth via Glutamate-dependent Ca2+-mediated Molecular Pathways. Cereb Cortex 2018; 27:131-145. [PMID: 27909001 PMCID: PMC5939201 DOI: 10.1093/cercor/bhw370] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Indexed: 12/28/2022] Open
Abstract
Altered synaptic bioactive lipid signaling has been recently shown to augment neuronal excitation in the hippocampus of adult animals by activation of presynaptic LPA2-receptors leading to increased presynaptic glutamate release. Here, we show that this results in higher postsynaptic Ca2+ levels and in premature onset of spontaneous neuronal activity in the developing entorhinal cortex. Interestingly, increased synchronized neuronal activity led to reduced axon growth velocity of entorhinal neurons which project via the perforant path to the hippocampus. This was due to Ca2+-dependent molecular signaling to the axon affecting stabilization of the actin cytoskeleton. The spontaneous activity affected the entire entorhinal cortical network and thus led to reduced overall axon fiber numbers in the mature perforant path that is known to be important for specific memory functions. Our data show that precise regulation of early cortical activity by bioactive lipids is of critical importance for proper circuit formation.
Collapse
Affiliation(s)
- Johannes Vogt
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Sergei Kirischuk
- Institute of Physiology, University Medical Center, Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Petr Unichenko
- Institute of Physiology, University Medical Center, Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Leslie Schlüter
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Assunta Pelosi
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Heiko Endle
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center, Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Nikolai Schmarowski
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Jin Cheng
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Carine Thalman
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Ulf Strauss
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin, 10119 Berlin, Germany
| | - Alexey Prokudin
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - B Suman Bharati
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, 980-8578, Japan
| | - Jerold Chun
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Beat Lutz
- Institute of Physiological Chemistry, University Medical Center, Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center, Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Robert Nitsch
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center, Johannes Gutenberg-University, 55131 Mainz, Germany
| |
Collapse
|
40
|
Allitt BJ, Alwis DS, Rajan R. Laminar-specific encoding of texture elements in rat barrel cortex. J Physiol 2017; 595:7223-7247. [PMID: 28929510 PMCID: PMC5709323 DOI: 10.1113/jp274865] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/06/2017] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS For rats texture discrimination is signalled by the large face whiskers by stick-slip events. Neural encoding of repetitive stick-slip events will be influenced by intrinsic properties of adaptation. We show that texture coding in the barrel cortex is laminar specific and follows a power function. Our results also show layer 2 codes for novel feature elements via robust firing rates and temporal fidelity. We conclude that texture coding relies on a subtle neural ensemble to provide important object information. ABSTRACT Texture discrimination by rats is exquisitely guided by fine-grain mechanical stick-slip motions of the face whiskers as they encounter, stick to and slip past successive texture-defining surface features such as bumps and grooves. Neural encoding of successive stick-slip texture events will be shaped by adaptation, common to all sensory systems, whereby receptor and neural responses to a stimulus are affected by responses to preceding stimuli, allowing resetting to signal novel information. Additionally, when a whisker is actively moved to contact and brush over surfaces, that motion itself generates neural responses that could cause adaptation of responses to subsequent stick-slip events. Nothing is known about encoding in the rat whisker system of stick-slip events defining textures of different grain or the influence of adaptation from whisker protraction or successive texture-defining stick-slip events. Here we recorded responses from halothane-anaesthetized rats in response to texture-defining stimuli applied to passive whiskers. We demonstrate that: across the columnar network of the whisker-recipient barrel cortex, adaptation in response to repetitive stick-slip events is strongest in uppermost layers and equally lower thereafter; neither whisker protraction speed nor stick-slip frequency impede encoding of stick-slip events at rates up to 34.08 Hz; and layer 2 normalizes responses to whisker protraction to resist effects on texture signalling. Thus, within laminar-specific response patterns, barrel cortex reliably encodes texture-defining elements even to high frequencies.
Collapse
Affiliation(s)
| | - Dasuni S. Alwis
- Department of PhysiologyMonash UniversityClaytonVIC3800Australia
| | - Ramesh Rajan
- Department of PhysiologyMonash UniversityClaytonVIC3800Australia
| |
Collapse
|
41
|
Systematic population spike delays across cortical layers within and between primary sensory areas. Sci Rep 2017; 7:15267. [PMID: 29127394 PMCID: PMC5681572 DOI: 10.1038/s41598-017-15611-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022] Open
Abstract
The coordinated propagation of activity across cortical layers enables simultaneous local computation and inter-areal interactions. A pattern of upward propagation from deeper to more superficial layers, which has been repeatedly demonstrated in spontaneous activity, would allow these functions to occur in parallel. But it remains unclear whether upward propagation also occurs for stimulus evoked activity, and how it relates to activity in other cortical areas. Here we used a new method to analyze relative delays between spikes obtained from simultaneous laminar recordings in primary sensory cortex (S1) of both hemispheres. The results identified systematic spike delays across cortical layers that showed a general upward propagation of activity in evoked and spontaneous activity. Systematic spike delays were also observed between hemispheres. After spikes in one S1 the delays in the other S1 were shortest at infragranular layers and increased in the upward direction. Model comparisons furthermore showed that upward propagation was better explained as a step-wise progression over cortical layers than as a traveling wave. The results are in line with the notion that upward propagation functionally integrates activity into local processing at superficial layers, while efficiently allowing for simultaneous inter-areal interactions.
Collapse
|
42
|
Hawkins J, Ahmad S, Cui Y. A Theory of How Columns in the Neocortex Enable Learning the Structure of the World. Front Neural Circuits 2017; 11:81. [PMID: 29118696 PMCID: PMC5661005 DOI: 10.3389/fncir.2017.00081] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 10/10/2017] [Indexed: 01/21/2023] Open
Abstract
Neocortical regions are organized into columns and layers. Connections between layers run mostly perpendicular to the surface suggesting a columnar functional organization. Some layers have long-range excitatory lateral connections suggesting interactions between columns. Similar patterns of connectivity exist in all regions but their exact role remain a mystery. In this paper, we propose a network model composed of columns and layers that performs robust object learning and recognition. Each column integrates its changing input over time to learn complete predictive models of observed objects. Excitatory lateral connections across columns allow the network to more rapidly infer objects based on the partial knowledge of adjacent columns. Because columns integrate input over time and space, the network learns models of complex objects that extend well beyond the receptive field of individual cells. Our network model introduces a new feature to cortical columns. We propose that a representation of location relative to the object being sensed is calculated within the sub-granular layers of each column. The location signal is provided as an input to the network, where it is combined with sensory data. Our model contains two layers and one or more columns. Simulations show that using Hebbian-like learning rules small single-column networks can learn to recognize hundreds of objects, with each object containing tens of features. Multi-column networks recognize objects with significantly fewer movements of the sensory receptors. Given the ubiquity of columnar and laminar connectivity patterns throughout the neocortex, we propose that columns and regions have more powerful recognition and modeling capabilities than previously assumed.
Collapse
Affiliation(s)
| | | | - Yuwei Cui
- Numenta, Inc., Redwood City, CA, United States
| |
Collapse
|
43
|
Dechery JB, MacLean JN. Emergent cortical circuit dynamics contain dense, interwoven ensembles of spike sequences. J Neurophysiol 2017; 118:1914-1925. [PMID: 28724786 DOI: 10.1152/jn.00394.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/05/2017] [Accepted: 07/14/2017] [Indexed: 01/30/2023] Open
Abstract
Temporal codes are theoretically powerful encoding schemes, but their precise form in the neocortex remains unknown in part because of the large number of possible codes and the difficulty in disambiguating informative spikes from statistical noise. A biologically plausible and computationally powerful temporal coding scheme is the Hebbian assembly phase sequence (APS), which predicts reliable propagation of spikes between functionally related assemblies of neurons. Here, we sought to measure the inherent capacity of neocortical networks to produce reliable sequences of spikes, as would be predicted by an APS code. To record microcircuit activity, the scale at which computation is implemented, we used two-photon calcium imaging to densely sample spontaneous activity in murine neocortical networks ex vivo. We show that the population spike histogram is sufficient to produce a spatiotemporal progression of activity across the population. To more comprehensively evaluate the capacity for sequential spiking that cannot be explained by the overall population spiking, we identify statistically significant spike sequences. We found a large repertoire of sequence spikes that collectively comprise the majority of spiking in the circuit. Sequences manifest probabilistically and share neuron membership, resulting in unique ensembles of interwoven sequences characterizing individual spatiotemporal progressions of activity. Distillation of population dynamics into its constituent sequences provides a way to capture trial-to-trial variability and may prove to be a powerful decoding substrate in vivo. Informed by these data, we suggest that the Hebbian APS be reformulated as interwoven sequences with flexible assembly membership due to shared overlapping neurons.NEW & NOTEWORTHY Neocortical computation occurs largely within microcircuits comprised of individual neurons and their connections within small volumes (<500 μm3). We found evidence for a long-postulated temporal code, the Hebbian assembly phase sequence, by identifying repeated and co-occurring sequences of spikes. Variance in population activity across trials was explained in part by the ensemble of active sequences. The presence of interwoven sequences suggests that neuronal assembly structure can be variable and is determined by previous activity.
Collapse
Affiliation(s)
- Joseph B Dechery
- Committee on Computational Neuroscience, University of Chicago, Chicago, Illinois; and
| | - Jason N MacLean
- Committee on Computational Neuroscience, University of Chicago, Chicago, Illinois; and .,Department of Neurobiology, University of Chicago, Illinois
| |
Collapse
|
44
|
Guy J, Staiger JF. The Functioning of a Cortex without Layers. Front Neuroanat 2017; 11:54. [PMID: 28747874 PMCID: PMC5506093 DOI: 10.3389/fnana.2017.00054] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/20/2017] [Indexed: 12/02/2022] Open
Abstract
A major hallmark of cortical organization is the existence of a variable number of layers, i.e., sheets of neurons stacked on top of each other, in which neurons have certain commonalities. However, even for the neocortex, variable numbers of layers have been described and it is just a convention to distinguish six layers from each other. Whether cortical layers are a structural epiphenomenon caused by developmental dynamics or represent a functionally important modularization of cortical computation is still unknown. Here we present our insights from the reeler mutant mouse, a model for a developmental, “molecular lesion”-induced loss of cortical layering that could serve as ground truth of what an intact layering adds to the cortex in terms of functionality. We could demonstrate that the reeler neocortex shows no inversion of cortical layers but rather a severe disorganization that in the primary somatosensory cortex leads to the complete loss of layers. Nevertheless, the somatosensory system is well organized. When exploring an enriched environment with specific sets of whiskers, activity-dependent gene expression takes place in the corresponding modules. Precise whisker stimuli lead to the functional activation of somatotopically organized barrel columns as visualized by intrinsic signal optical imaging. Similar results were obtained in the reeler visual system. When analyzing pathways that could be responsible for preservation of tactile perception, lemniscal thalamic projections were found to be largely intact, despite the smearing of target neurons across the cortical mantle. However, with optogenetic experiments we found evidence for a mild dispersion of thalamic synapse targeting on layer IV-spiny stellate cells, together with a general weakening in thalamocortical input strength. This weakening of thalamic inputs was compensated by intracortical mechanisms involving increased recurrent excitation and/or reduced feedforward inhibition. In conclusion, a layer loss so far only led to the detection of subtle defects in sensory processing by reeler mice. This argues in favor of a view in which cortical layers are not an essential component for basic perception and cognition. A view also supported by recent studies in birds, which can have remarkable cognitive capacities despite the lack of a neocortex with multiple cortical layers. In conclusion, we suggest that future studies directed toward understanding cortical functions should rather focus on circuits specified by functional cell type composition than mere laminar location.
Collapse
Affiliation(s)
- Julien Guy
- Institute for Neuroanatomy, University Medical Center Göttingen, Georg-August-UniversityGöttingen, Germany
| | - Jochen F Staiger
- Institute for Neuroanatomy, University Medical Center Göttingen, Georg-August-UniversityGöttingen, Germany.,DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany
| |
Collapse
|
45
|
Luhmann HJ. Review of imaging network activities in developing rodent cerebral cortex in vivo. NEUROPHOTONICS 2017; 4:031202. [PMID: 27921066 PMCID: PMC5120148 DOI: 10.1117/1.nph.4.3.031202] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 10/19/2016] [Indexed: 06/06/2023]
Abstract
The combination of voltage-sensitive dye imaging (VSDI) with multielectrode array (MEA) recordings in the rodent cerebral cortex in vivo allows the simultaneous analysis of large-scale network interactions and electrophysiological single-unit recordings. Using this approach, distinct patterns of spontaneous and sensory-evoked activity can be recorded in the primary somatosensory (S1) and motor cortex (M1) of newborn rats. Already at the day of birth, gamma oscillations and spindle bursts in the barrel cortex synchronize the activity of a local columnar ensemble, thereby generating an early topographic representation of the sensory periphery. During the first postnatal week, both cortical activity patterns undergo developmental changes in their spatiotemporal properties and spread into neighboring cortical columns. Simultaneous VSDI and MEA recordings in S1 and M1 demonstrate that the immature motor cortex receives information from the somatosensory system and that M1 may trigger movements of the periphery, which subsequently evoke gamma oscillations and spindle bursts in S1. These early activity patterns not only play an important role in the development of the cortical columnar architecture, they also control the ratio of surviving versus dying neurons in an activity-dependent manner, making these processes most vulnerable to pathophysiological disturbances during early developmental stages.
Collapse
Affiliation(s)
- Heiko J. Luhmann
- University Medical Center of the Johannes Gutenberg University Mainz, Institute of Physiology, Duesbergweg 6, 55128 Mainz, Germany
| |
Collapse
|
46
|
Hagen E, Dahmen D, Stavrinou ML, Lindén H, Tetzlaff T, van Albada SJ, Grün S, Diesmann M, Einevoll GT. Hybrid Scheme for Modeling Local Field Potentials from Point-Neuron Networks. Cereb Cortex 2016; 26:4461-4496. [PMID: 27797828 PMCID: PMC6193674 DOI: 10.1093/cercor/bhw237] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 05/31/2016] [Accepted: 07/12/2016] [Indexed: 12/21/2022] Open
Abstract
With rapidly advancing multi-electrode recording technology, the local field potential (LFP) has again become a popular measure of neuronal activity in both research and clinical applications. Proper understanding of the LFP requires detailed mathematical modeling incorporating the anatomical and electrophysiological features of neurons near the recording electrode, as well as synaptic inputs from the entire network. Here we propose a hybrid modeling scheme combining efficient point-neuron network models with biophysical principles underlying LFP generation by real neurons. The LFP predictions rely on populations of network-equivalent multicompartment neuron models with layer-specific synaptic connectivity, can be used with an arbitrary number of point-neuron network populations, and allows for a full separation of simulated network dynamics and LFPs. We apply the scheme to a full-scale cortical network model for a ∼1 mm2 patch of primary visual cortex, predict laminar LFPs for different network states, assess the relative LFP contribution from different laminar populations, and investigate effects of input correlations and neuron density on the LFP. The generic nature of the hybrid scheme and its public implementation in hybridLFPy form the basis for LFP predictions from other and larger point-neuron network models, as well as extensions of the current application with additional biological detail.
Collapse
Affiliation(s)
- Espen Hagen
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute I, Jülich Research Centre, 52425 Jülich, Germany.,Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, 1430 Ås, Norway
| | - David Dahmen
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute I, Jülich Research Centre, 52425 Jülich, Germany
| | - Maria L Stavrinou
- Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, 1430 Ås, Norway.,Department of Psychology, University of Oslo, 0373 Oslo, Norway
| | - Henrik Lindén
- Department of Neuroscience and Pharmacology, University of Copenhagen, 2200 Copenhagen, Denmark.,Department of Computational Biology, School of Computer Science and Communication, Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Tom Tetzlaff
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute I, Jülich Research Centre, 52425 Jülich, Germany
| | - Sacha J van Albada
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute I, Jülich Research Centre, 52425 Jülich, Germany
| | - Sonja Grün
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute I, Jülich Research Centre, 52425 Jülich, Germany.,Theoretical Systems Neurobiology, RWTH Aachen University, 52056 Aachen, Germany
| | - Markus Diesmann
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute I, Jülich Research Centre, 52425 Jülich, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany.,Department of Physics, Faculty 1, RWTH Aachen University, 52062 Aachen, Germany
| | - Gaute T Einevoll
- Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, 1430 Ås, Norway.,Department of Physics, University of Oslo, 0316 Oslo, Norway
| |
Collapse
|
47
|
Naka A, Adesnik H. Inhibitory Circuits in Cortical Layer 5. Front Neural Circuits 2016; 10:35. [PMID: 27199675 PMCID: PMC4859073 DOI: 10.3389/fncir.2016.00035] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/18/2016] [Indexed: 01/19/2023] Open
Abstract
Inhibitory neurons play a fundamental role in cortical computation and behavior. Recent technological advances, such as two photon imaging, targeted in vivo recording, and molecular profiling, have improved our understanding of the function and diversity of cortical interneurons, but for technical reasons most work has been directed towards inhibitory neurons in the superficial cortical layers. Here we review current knowledge specifically on layer 5 (L5) inhibitory microcircuits, which play a critical role in controlling cortical output. We focus on recent work from the well-studied rodent barrel cortex, but also draw on evidence from studies in primary visual cortex and other cortical areas. The diversity of both deep inhibitory neurons and their pyramidal cell targets make this a challenging but essential area of study in cortical computation and sensory processing.
Collapse
Affiliation(s)
- Alexander Naka
- The Helen Wills Neuroscience Institute, University of California Berkeley Berkeley, CA, USA
| | - Hillel Adesnik
- The Helen Wills Neuroscience Institute, University of California BerkeleyBerkeley, CA, USA; Department of Molecular and Cell Biology, University of California BerkeleyBerkeley, CA, USA
| |
Collapse
|
48
|
In Vivo Mesoscopic Voltage-Sensitive Dye Imaging of Brain Activation. Sci Rep 2016; 6:25269. [PMID: 27125318 PMCID: PMC4850485 DOI: 10.1038/srep25269] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 04/14/2016] [Indexed: 02/02/2023] Open
Abstract
Functional mapping of brain activity is important in elucidating how neural networks operate in the living brain. The whisker sensory system of rodents is an excellent model to study peripherally evoked neural activity in the central nervous system. Each facial whisker is represented by discrete modules of neurons all along the pathway leading to the neocortex. These modules are called "barrels" in layer 4 of the primary somatosensory cortex. Their location (approximately 300-500 μm below cortical surface) allows for convenient imaging of whisker-evoked neural activity in vivo. Fluorescence laminar optical tomography (FLOT) provides depth-resolved fluorescence molecular information with an imaging depth of a few millimeters. Angled illumination and detection configurations can improve both resolution and penetration depth. We applied angled FLOT (aFLOT) to record 3D neural activities evoked in the whisker system of mice by deflection of a single whisker in vivo. A 100 μm capillary and a pair of microelectrodes were inserted to the mouse brain to test the capability of the imaging system. The results show that it is possible to obtain 3D functional maps of the sensory periphery in the brain. This approach can be broadly applicable to functional imaging of other brain structures.
Collapse
|
49
|
Reyes-Puerta V, Yang JW, Siwek ME, Kilb W, Sun JJ, Luhmann HJ. Propagation of spontaneous slow-wave activity across columns and layers of the adult rat barrel cortex in vivo. Brain Struct Funct 2016; 221:4429-4449. [PMID: 26754838 DOI: 10.1007/s00429-015-1173-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 12/16/2015] [Indexed: 12/19/2022]
Abstract
During slow-wave sleep, neocortical networks exhibit self-organized activity switching between periods of concurrent spiking (up-states) and periods of network silence (down-states), a phenomenon also occurring under the effects of different anesthetics and in in vitro brain slice preparations. Although this type of ongoing activity has been implicated into important functions such as memory consolidation and learning, the manner in which it propagates across different cortical modules (i.e., columns and layers) has not been fully characterized. In the present study, we investigated this issue by measuring spontaneous activity at large scale in the adult rat barrel cortex under urethane anesthesia by means of voltage-sensitive dye imaging and 128-channel probe recordings. Up to 74 neurons located in all layers of up to four functionally identified barrel-related columns were recorded simultaneously. The spontaneous activity propagated isotropically across the cortical surface with a median speed of ~35 µm/ms. A concomitant radial spread of activation was present from deep to superficial cortical layers. Thus, spontaneous activity occurred rather globally in the barrel cortex, with ≥50 % of the up-states presenting spikes in ≥3 columns and layers. Temporally precise spike sequences, which occurred repeatedly (although sporadically) within the up-states, were typically led by putative excitatory neurons in the infragranular cortical layers. In summary, our data provide for the first time an overall view of the spontaneous slow-wave activity within the barrel cortex circuit, characterizing its propagation across columns and layers at high spatio-temporal resolution.
Collapse
Affiliation(s)
- Vicente Reyes-Puerta
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128, Mainz, Germany.
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128, Mainz, Germany
| | - Magdalena E Siwek
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128, Mainz, Germany
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128, Mainz, Germany
| | - Jyh-Jang Sun
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128, Mainz, Germany.
- Neuro-Electronics Research Flanders, Kapeldreef 75, 3001, Louvain, Belgium.
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128, Mainz, Germany
| |
Collapse
|
50
|
Dufour A, Rollenhagen A, Sätzler K, Lübke JHR. Development of Synaptic Boutons in Layer 4 of the Barrel Field of the Rat Somatosensory Cortex: A Quantitative Analysis. Cereb Cortex 2015; 26:838-854. [PMID: 26574502 PMCID: PMC4712807 DOI: 10.1093/cercor/bhv270] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Understanding the structural and functional mechanisms underlying the development of individual brain microcircuits is critical for elucidating their computational properties. As synapses are the key structures defining a given microcircuit, it is imperative to investigate their development and precise structural features. Here, synapses in cortical layer 4 were analyzed throughout the first postnatal month using high-end electron microscopy to generate realistic quantitative 3D models. Besides their overall geometry, the size of active zones and the pools of synaptic vesicles were analyzed. At postnatal day 2 only a few shaft synapses were found, but spine synapses steadily increased with ongoing corticogenesis. From postnatal day 2 to 30 synaptic boutons significantly decreased in size whereas that of active zones remained nearly unchanged despite a reshaping. During the first 2 weeks of postnatal development, a rearrangement of synaptic vesicles from a loose distribution toward a densely packed organization close to the presynaptic density was observed, accompanied by the formation of, first a putative readily releasable pool and later a recycling and reserve pool. The quantitative 3D reconstructions of synapses will enable the comparison of structural and functional aspects of signal transduction thus leading to a better understanding of networks in the developing neocortex.
Collapse
Affiliation(s)
- Amandine Dufour
- Institute of Neuroscience and Medicine INM-2, Research Centre Jülich GmbH, Jülich 52425, Germany.,Institute of Anatomy II, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Astrid Rollenhagen
- Institute of Neuroscience and Medicine INM-2, Research Centre Jülich GmbH, Jülich 52425, Germany
| | - Kurt Sätzler
- School of Biomedical Sciences, University of Ulster, Londonderry BT52 1SA, UK
| | - Joachim H R Lübke
- Institute of Neuroscience and Medicine INM-2, Research Centre Jülich GmbH, Jülich 52425, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH/University Hospital Aachen, Aachen 52074, Germany.,JARA Translational Brain Medicine, Aachen 52074, Germany
| |
Collapse
|