1
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Ng KKW, So A, Fang JY, Birznieks I, Vickery RM. Multiplexing intensity and frequency sensations for artificial touch by modulating temporal features of electrical pulse trains. Front Neurosci 2024; 18:1125597. [PMID: 38894940 PMCID: PMC11183272 DOI: 10.3389/fnins.2024.1125597] [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: 12/16/2022] [Accepted: 05/20/2024] [Indexed: 06/21/2024] Open
Abstract
In neural prostheses, intensity modulation of a single channel (i.e., through a single stimulating electrode) has been achieved by increasing the magnitude or width of each stimulation pulse, which risks eliciting pain or paraesthesia; and by changing the stimulation rate, which leads to concurrent changes in perceived frequency. In this study, we sought to render a perception of tactile intensity and frequency independently, by means of temporal pulse train patterns of fixed magnitude, delivered non-invasively. Our psychophysical study exploits a previously discovered frequency coding mechanism, where the perceived frequency of stimulus pulses grouped into periodic bursts depends on the duration of the inter-burst interval, rather than the mean pulse rate or periodicity. When electrical stimulus pulses were organised into bursts, perceived intensity was influenced by the number of pulses within a burst, while perceived frequency was determined by the time between the end of one burst envelope and the start of the next. The perceived amplitude was modulated by 1.6× while perceived frequency was varied independently by 2× within the tested range (20-40 Hz). Thus, the sensation of intensity might be controlled independently from frequency through a single stimulation channel without having to vary the injected electrical current. This can form the basis for improving strategies in delivering more complex and natural sensations for prosthetic hand users.
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Affiliation(s)
- Kevin K. W. Ng
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- School of Biomedical Sciences, UNSW Sydney, Sydney, NSW, Australia
| | - Alwin So
- School of Biomedical Sciences, UNSW Sydney, Sydney, NSW, Australia
- Neuroscience Research Australia, Sydney, NSW, Australia
| | - Jun Yi Fang
- School of Biomedical Sciences, UNSW Sydney, Sydney, NSW, Australia
- Neuroscience Research Australia, Sydney, NSW, Australia
| | - Ingvars Birznieks
- School of Biomedical Sciences, UNSW Sydney, Sydney, NSW, Australia
- Neuroscience Research Australia, Sydney, NSW, Australia
- Bionics and Bio-robotics, Tyree Foundation Institute of Health Engineering, UNSW Sydney, Sydney, NSW, Australia
| | - Richard M. Vickery
- School of Biomedical Sciences, UNSW Sydney, Sydney, NSW, Australia
- Neuroscience Research Australia, Sydney, NSW, Australia
- Bionics and Bio-robotics, Tyree Foundation Institute of Health Engineering, UNSW Sydney, Sydney, NSW, Australia
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2
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Crombie D, Spacek MA, Leibold C, Busse L. Spiking activity in the visual thalamus is coupled to pupil dynamics across temporal scales. PLoS Biol 2024; 22:e3002614. [PMID: 38743775 PMCID: PMC11093384 DOI: 10.1371/journal.pbio.3002614] [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: 07/14/2023] [Accepted: 04/05/2024] [Indexed: 05/16/2024] Open
Abstract
The processing of sensory information, even at early stages, is influenced by the internal state of the animal. Internal states, such as arousal, are often characterized by relating neural activity to a single "level" of arousal, defined by a behavioral indicator such as pupil size. In this study, we expand the understanding of arousal-related modulations in sensory systems by uncovering multiple timescales of pupil dynamics and their relationship to neural activity. Specifically, we observed a robust coupling between spiking activity in the mouse dorsolateral geniculate nucleus (dLGN) of the thalamus and pupil dynamics across timescales spanning a few seconds to several minutes. Throughout all these timescales, 2 distinct spiking modes-individual tonic spikes and tightly clustered bursts of spikes-preferred opposite phases of pupil dynamics. This multi-scale coupling reveals modulations distinct from those captured by pupil size per se, locomotion, and eye movements. Furthermore, coupling persisted even during viewing of a naturalistic movie, where it contributed to differences in the encoding of visual information. We conclude that dLGN spiking activity is under the simultaneous influence of multiple arousal-related processes associated with pupil dynamics occurring over a broad range of timescales.
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Affiliation(s)
- Davide Crombie
- Division of Neuroscience, Faculty of Biology, LMU Munich, Munich, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Munich, Germany
| | - Martin A. Spacek
- Division of Neuroscience, Faculty of Biology, LMU Munich, Munich, Germany
| | - Christian Leibold
- Division of Neuroscience, Faculty of Biology, LMU Munich, Munich, Germany
- Fakultät für Biologie & Bernstein Center Freiburg, Albert-Ludwigs-Universität Freiburg, Freiburg im Breisgau, Germany
| | - Laura Busse
- Division of Neuroscience, Faculty of Biology, LMU Munich, Munich, Germany
- Bernstein Center for Computational Neuroscience, Munich, Germany
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3
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Mukherjee A, Halassa MM. The Associative Thalamus: A Switchboard for Cortical Operations and a Promising Target for Schizophrenia. Neuroscientist 2024; 30:132-147. [PMID: 38279699 PMCID: PMC10822032 DOI: 10.1177/10738584221112861] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2024]
Abstract
Schizophrenia is a brain disorder that profoundly perturbs cognitive processing. Despite the success in treating many of its symptoms, the field lacks effective methods to measure and address its impact on reasoning, inference, and decision making. Prefrontal cortical abnormalities have been well documented in schizophrenia, but additional dysfunction in the interactions between the prefrontal cortex and thalamus have recently been described. This dysfunction may be interpreted in light of parallel advances in neural circuit research based on nonhuman animals, which show critical thalamic roles in maintaining and switching prefrontal activity patterns in various cognitive tasks. Here, we review this basic literature and connect it to emerging innovations in clinical research. We highlight the value of focusing on associative thalamic structures not only to better understand the very nature of cognitive processing but also to leverage these circuits for diagnostic and therapeutic development in schizophrenia. We suggest that the time is right for building close bridges between basic thalamic research and its clinical translation, particularly in the domain of cognition and schizophrenia.
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Affiliation(s)
- Arghya Mukherjee
- Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Michael M Halassa
- Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
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4
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Friedenberger Z, Harkin E, Tóth K, Naud R. Silences, spikes and bursts: Three-part knot of the neural code. J Physiol 2023; 601:5165-5193. [PMID: 37889516 DOI: 10.1113/jp281510] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 09/28/2023] [Indexed: 10/28/2023] Open
Abstract
When a neuron breaks silence, it can emit action potentials in a number of patterns. Some responses are so sudden and intense that electrophysiologists felt the need to single them out, labelling action potentials emitted at a particularly high frequency with a metonym - bursts. Is there more to bursts than a figure of speech? After all, sudden bouts of high-frequency firing are expected to occur whenever inputs surge. The burst coding hypothesis advances that the neural code has three syllables: silences, spikes and bursts. We review evidence supporting this ternary code in terms of devoted mechanisms for burst generation, synaptic transmission and synaptic plasticity. We also review the learning and attention theories for which such a triad is beneficial.
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Affiliation(s)
- Zachary Friedenberger
- Brain and Mind Institute, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Neural Dynamics and Artifical Intelligence, Department of Physics, University of Ottawa, Ottawa, Ontario, Ottawa
| | - Emerson Harkin
- Brain and Mind Institute, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Katalin Tóth
- Brain and Mind Institute, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Richard Naud
- Brain and Mind Institute, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Centre for Neural Dynamics and Artifical Intelligence, Department of Physics, University of Ottawa, Ottawa, Ontario, Ottawa
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5
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Zhang K, Liu Y, Song Y, Xu S, Yang Y, Jiang L, Sun S, Luo J, Wu Y, Cai X. Exploring retinal ganglion cells encoding to multi-modal stimulation using 3D microelectrodes arrays. Front Bioeng Biotechnol 2023; 11:1245082. [PMID: 37600306 PMCID: PMC10434521 DOI: 10.3389/fbioe.2023.1245082] [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: 06/23/2023] [Accepted: 07/21/2023] [Indexed: 08/22/2023] Open
Abstract
Microelectrode arrays (MEA) are extensively utilized in encoding studies of retinal ganglion cells (RGCs) due to their capacity for simultaneous recording of neural activity across multiple channels. However, conventional planar MEAs face limitations in studying RGCs due to poor coupling between electrodes and RGCs, resulting in low signal-to-noise ratio (SNR) and limited recording sensitivity. To overcome these challenges, we employed photolithography, electroplating, and other processes to fabricate a 3D MEA based on the planar MEA platform. The 3D MEA exhibited several improvements compared to planar MEA, including lower impedance (8.73 ± 1.66 kΩ) and phase delay (-15.11° ± 1.27°), as well as higher charge storage capacity (CSC = 10.16 ± 0.81 mC/cm2), cathodic charge storage capacity (CSCc = 7.10 ± 0.55 mC/cm2), and SNR (SNR = 8.91 ± 0.57). Leveraging the advanced 3D MEA, we investigated the encoding characteristics of RGCs under multi-modal stimulation. Optical, electrical, and chemical stimulation were applied as sensory inputs, and distinct response patterns and response times of RGCs were detected, as well as variations in rate encoding and temporal encoding. Specifically, electrical stimulation elicited more effective RGC firing, while optical stimulation enhanced RGC synchrony. These findings hold promise for advancing the field of neural encoding.
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Affiliation(s)
- Kui Zhang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Yaoyao Liu
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Yilin Song
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Shihong Xu
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Yan Yang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Longhui Jiang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Shutong Sun
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Jinping Luo
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Yirong Wu
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Xinxia Cai
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China
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6
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Sanchez AN, Alitto HJ, Rathbun DL, Fisher TG, Usrey WM. Stimulus contrast modulates burst activity in the lateral geniculate nucleus. CURRENT RESEARCH IN NEUROBIOLOGY 2023; 4:100096. [PMID: 37397805 PMCID: PMC10313900 DOI: 10.1016/j.crneur.2023.100096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 06/03/2023] [Accepted: 06/08/2023] [Indexed: 07/04/2023] Open
Abstract
Burst activity is a ubiquitous feature of thalamic neurons and is well documented for visual neurons in the lateral geniculate nucleus (LGN). Although bursts are often associated with states of drowsiness, they are also known to convey visual information to cortex and are particularly effective in evoking cortical responses. The occurrence of thalamic bursts depends on (1) the inactivation gate of T-type Ca2+ channels (T-channels), which become de-inactivated following periods of increased membrane hyperpolarization, and (2) the opening of the T-channel activation gate, which has voltage-threshold and rate-of-change (δv/δt) requirements. Given the time/voltage relationship for the generation of Ca2+ potentials that underlie burst events, it is reasonable to predict that geniculate bursts are influenced by the luminance contrast of drifting grating stimuli, with the null phase of higher contrast stimuli evoking greater hyperpolarization followed by a larger dv/dt than the null phase of lower contrast stimuli. To determine the relationship between stimulus contrast and burst activity, we recorded the spiking activity of cat LGN neurons while presenting drifting sine-wave gratings that varied in luminance contrast. Results show that burst rate, reliability, and timing precision are significantly greater with higher contrast stimuli compared with lower contrast stimuli. Additional analysis from simultaneous recordings of synaptically connected retinal ganglion cells and LGN neurons further reveals the time/voltage dynamics underlying burst activity. Together, these results support the hypothesis that stimulus contrast and the biophysical properties underlying the state of T-type Ca2+ channels interact to influence burst activity, presumably to facilitate thalamocortical communication and stimulus detection.
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Affiliation(s)
| | - Henry J. Alitto
- Center for Neuroscience, University of California Davis, 95618, USA
| | - Daniel L. Rathbun
- Dept. of Ophthalmology, Detroit Inst. of Ophthalmology, Henry Ford Health System, Detroit, MI, 48202, USA
| | | | - W. Martin Usrey
- Center for Neuroscience, University of California Davis, 95618, USA
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7
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Sharma H, Azouz R. Coexisting neuronal coding strategies in the barrel cortex. Cereb Cortex 2022; 32:4986-5004. [PMID: 35149866 DOI: 10.1093/cercor/bhab527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 12/27/2022] Open
Abstract
During tactile sensation by rodents, whisker movements across surfaces generate complex whisker motions, including discrete, transient stick-slip events, which carry information about surface properties. The characteristics of these events and how the brain encodes this tactile information remain enigmatic. We found that cortical neurons show a mixture of synchronized and nontemporally correlated spikes in their tactile responses. Synchronous spikes convey the magnitude of stick-slip events by numerous aspects of temporal coding. These spikes show preferential selectivity for kinetic and kinematic whisker motion. By contrast, asynchronous spikes in each neuron convey the magnitude of stick-slip events by their discharge rates, response probability, and interspike intervals. We further show that the differentiation between these two types of activity is highly dependent on the magnitude of stick-slip events and stimulus and response history. These results suggest that cortical neurons transmit multiple components of tactile information through numerous coding strategies.
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Affiliation(s)
- Hariom Sharma
- Department of Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Rony Azouz
- Department of Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, Israel
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8
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Chen ZS, Zhang X, Long X, Zhang SJ. Are Grid-Like Representations a Component of All Perception and Cognition? Front Neural Circuits 2022; 16:924016. [PMID: 35911570 PMCID: PMC9329517 DOI: 10.3389/fncir.2022.924016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 06/14/2022] [Indexed: 11/24/2022] Open
Abstract
Grid cells or grid-like responses have been reported in the rodent, bat and human brains during various spatial and non-spatial tasks. However, the functions of grid-like representations beyond the classical hippocampal formation remain elusive. Based on accumulating evidence from recent rodent recordings and human fMRI data, we make speculative accounts regarding the mechanisms and functional significance of the sensory cortical grid cells and further make theory-driven predictions. We argue and reason the rationale why grid responses may be universal in the brain for a wide range of perceptual and cognitive tasks that involve locomotion and mental navigation. Computational modeling may provide an alternative and complementary means to investigate the grid code or grid-like map. We hope that the new discussion will lead to experimentally testable hypotheses and drive future experimental data collection.
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Affiliation(s)
- Zhe Sage Chen
- Department of Psychiatry, Department of Neuroscience and Physiology, Neuroscience Institute, New York University School of Medicine, New York, NY, United States
- *Correspondence: Zhe Sage Chen
| | - Xiaohan Zhang
- Department of Psychiatry, Department of Neuroscience and Physiology, Neuroscience Institute, New York University School of Medicine, New York, NY, United States
| | - Xiaoyang Long
- Department of Neurosurgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Sheng-Jia Zhang
- Department of Neurosurgery, Xinqiao Hospital, Army Medical University, Chongqing, China
- Sheng-Jia Zhang
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9
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Spacek MA, Crombie D, Bauer Y, Born G, Liu X, Katzner S, Busse L. Robust effects of corticothalamic feedback and behavioral state on movie responses in mouse dLGN. eLife 2022; 11:70469. [PMID: 35315775 PMCID: PMC9020820 DOI: 10.7554/elife.70469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 03/13/2022] [Indexed: 11/13/2022] Open
Abstract
Neurons in the dorsolateral geniculate nucleus (dLGN) of the thalamus receive a substantial proportion of modulatory inputs from corticothalamic (CT) feedback and brain stem nuclei. Hypothesizing that these modulatory influences might be differentially engaged depending on the visual stimulus and behavioral state, we performed in vivo extracellular recordings from mouse dLGN while optogenetically suppressing CT feedback and monitoring behavioral state by locomotion and pupil dilation. For naturalistic movie clips, we found CT feedback to consistently increase dLGN response gain and promote tonic firing. In contrast, for gratings, CT feedback effects on firing rates were mixed. For both stimulus types, the neural signatures of CT feedback closely resembled those of behavioral state, yet effects of behavioral state on responses to movies persisted even when CT feedback was suppressed. We conclude that CT feedback modulates visual information on its way to cortex in a stimulus-dependent manner, but largely independently of behavioral state.
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Affiliation(s)
- Martin A Spacek
- Division of Neurobiology, LMU Munich, Planegg-Martinsried, Germany
| | - Davide Crombie
- Division of Neurobiology, LMU Munich, Planegg-Martinsried, Germany
| | - Yannik Bauer
- Division of Neurobiology, LMU Munich, Planegg-Martinsried, Germany
| | - Gregory Born
- Division of Neurobiology, LMU Munich, Planegg-Martinsried, Germany
| | - Xinyu Liu
- Division of Neurobiology, LMU Munich, Planegg-Martinsried, Germany
| | | | - Laura Busse
- Division of Neurobiology, LMU Munich, Planegg-Martinsried, Germany
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10
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Mease RA, Gonzalez AJ. Corticothalamic Pathways From Layer 5: Emerging Roles in Computation and Pathology. Front Neural Circuits 2021; 15:730211. [PMID: 34566583 PMCID: PMC8458899 DOI: 10.3389/fncir.2021.730211] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 08/10/2021] [Indexed: 11/29/2022] Open
Abstract
Large portions of the thalamus receive strong driving input from cortical layer 5 (L5) neurons but the role of this important pathway in cortical and thalamic computations is not well understood. L5-recipient "higher-order" thalamic regions participate in cortico-thalamo-cortical (CTC) circuits that are increasingly recognized to be (1) anatomically and functionally distinct from better-studied "first-order" CTC networks, and (2) integral to cortical activity related to learning and perception. Additionally, studies are beginning to elucidate the clinical relevance of these networks, as dysfunction across these pathways have been implicated in several pathological states. In this review, we highlight recent advances in understanding L5 CTC networks across sensory modalities and brain regions, particularly studies leveraging cell-type-specific tools that allow precise experimental access to L5 CTC circuits. We aim to provide a focused and accessible summary of the anatomical, physiological, and computational properties of L5-originating CTC networks, and outline their underappreciated contribution in pathology. We particularly seek to connect single-neuron and synaptic properties to network (dys)function and emerging theories of cortical computation, and highlight information processing in L5 CTC networks as a promising focus for computational studies.
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Affiliation(s)
- Rebecca A. Mease
- Institute of Physiology and Pathophysiology, Medical Biophysics, Heidelberg University, Heidelberg, Germany
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11
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Williams E, Payeur A, Gidon A, Naud R. Neural burst codes disguised as rate codes. Sci Rep 2021; 11:15910. [PMID: 34354118 PMCID: PMC8342467 DOI: 10.1038/s41598-021-95037-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/13/2021] [Indexed: 02/07/2023] Open
Abstract
The burst coding hypothesis posits that the occurrence of sudden high-frequency patterns of action potentials constitutes a salient syllable of the neural code. Many neurons, however, do not produce clearly demarcated bursts, an observation invoked to rule out the pervasiveness of this coding scheme across brain areas and cell types. Here we ask how detrimental ambiguous spike patterns, those that are neither clearly bursts nor isolated spikes, are for neuronal information transfer. We addressed this question using information theory and computational simulations. By quantifying how information transmission depends on firing statistics, we found that the information transmitted is not strongly influenced by the presence of clearly demarcated modes in the interspike interval distribution, a feature often used to identify the presence of burst coding. Instead, we found that neurons having unimodal interval distributions were still able to ascribe different meanings to bursts and isolated spikes. In this regime, information transmission depends on dynamical properties of the synapses as well as the length and relative frequency of bursts. Furthermore, we found that common metrics used to quantify burstiness were unable to predict the degree with which bursts could be used to carry information. Our results provide guiding principles for the implementation of coding strategies based on spike-timing patterns, and show that even unimodal firing statistics can be consistent with a bivariate neural code.
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Affiliation(s)
- Ezekiel Williams
- grid.28046.380000 0001 2182 2255Department of Mathematics and Statistics, University of Ottawa, 150 Louis Pasteur, Ottawa, K1N 6N5 Canada
| | - Alexandre Payeur
- grid.28046.380000 0001 2182 2255University of Ottawa Brain and Mind Institute, Centre for Neural Dynamics, Department of Cellular and Molecular Medicine, University of Ottawa, 451 Smyth Rd., Ottawa, K1H 8M5 Canada
| | - Albert Gidon
- grid.7468.d0000 0001 2248 7639Institute for Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Richard Naud
- grid.28046.380000 0001 2182 2255University of Ottawa Brain and Mind Institute, Centre for Neural Dynamics, Department of Cellular and Molecular Medicine, University of Ottawa, 451 Smyth Rd., Ottawa, K1H 8M5 Canada ,grid.28046.380000 0001 2182 2255Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, K1N 6N5 Canada
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12
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de Kock CPJ, Pie J, Pieneman AW, Mease RA, Bast A, Guest JM, Oberlaender M, Mansvelder HD, Sakmann B. High-frequency burst spiking in layer 5 thick-tufted pyramids of rat primary somatosensory cortex encodes exploratory touch. Commun Biol 2021; 4:709. [PMID: 34112934 PMCID: PMC8192911 DOI: 10.1038/s42003-021-02241-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 05/18/2021] [Indexed: 01/14/2023] Open
Abstract
Diversity of cell-types that collectively shape the cortical microcircuit ensures the necessary computational richness to orchestrate a wide variety of behaviors. The information content embedded in spiking activity of identified cell-types remain unclear to a large extent. Here, we recorded spike responses upon whisker touch of anatomically identified excitatory cell-types in primary somatosensory cortex in naive, untrained rats. We find major differences across layers and cell-types. The temporal structure of spontaneous spiking contains high-frequency bursts (≥100 Hz) in all morphological cell-types but a significant increase upon whisker touch is restricted to layer L5 thick-tufted pyramids (L5tts) and thus provides a distinct neurophysiological signature. We find that whisker touch can also be decoded from L5tt bursting, but not from other cell-types. We observed high-frequency bursts in L5tts projecting to different subcortical regions, including thalamus, midbrain and brainstem. We conclude that bursts in L5tts allow accurate coding and decoding of exploratory whisker touch. In order to investigate the information encoded by spiking activity in different neuronal cell types in the primary somatosensory cortex, de Kock et al performed electrophysiological recordings in untrained rats. They demonstrated that an increase in high-frequency burst spiking in thick tufted pyramids in layer 5 of the cortex allow accurate encoding of exploratory whisker touch.
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Affiliation(s)
- Christiaan P J de Kock
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU, Amsterdam, the Netherlands.
| | - Jean Pie
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU, Amsterdam, the Netherlands.,University of Amsterdam, Swammerdam Institute for Life Sciences, Amsterdam, Netherlands
| | - Anton W Pieneman
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU, Amsterdam, the Netherlands
| | - Rebecca A Mease
- Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany
| | - Arco Bast
- Max Planck Group: In Silico Brain Sciences, Center of Advanced European Studies and Research, Bonn, Germany
| | - Jason M Guest
- Max Planck Group: In Silico Brain Sciences, Center of Advanced European Studies and Research, Bonn, Germany
| | - Marcel Oberlaender
- Max Planck Group: In Silico Brain Sciences, Center of Advanced European Studies and Research, Bonn, Germany
| | - Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU, Amsterdam, the Netherlands
| | - Bert Sakmann
- Max Planck Institute for Neurobiology, Martinsried, Germany
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13
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Schäfer CB, Gao Z, De Zeeuw CI, Hoebeek FE. Temporal dynamics of the cerebello-cortical convergence in ventro-lateral motor thalamus. J Physiol 2021; 599:2055-2073. [PMID: 33492688 PMCID: PMC8048920 DOI: 10.1113/jp280455] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 01/11/2021] [Indexed: 01/31/2023] Open
Abstract
KEY POINTS Ventrolateral thalamus (VL) integrates information from cerebellar nuclei and motor cortical layer VI. Inputs from the cerebellar nuclei evoke large-amplitude responses that depress upon repetitive stimulation while layer VI inputs from motor cortex induce small-amplitude facilitating responses. We report that the spiking of VL neurons can be determined by the thalamic membrane potential, the frequency of cerebellar inputs and the duration of pauses after cerebellar high frequency stimulation. Inputs from motor cortical layer VI shift the VL membrane potential and modulate the VL spike output in response to cerebellar stimulation. These results help us to decipher how the cerebellar output is integrated in VL and modulated by motor cortical input. ABSTRACT Orchestrating complex movements requires well-timed interaction of cerebellar, thalamic and cerebral structures, but the mechanisms underlying the integration of cerebro-cerebellar information in motor thalamus remain largely unknown. Here we investigated how excitatory inputs from cerebellar nuclei (CN) and primary motor cortex layer VI (M1-L6) neurons may regulate the activity of neurons in the mouse ventrolateral (VL) thalamus. Using dual-optical stimulation of the CN and M1-L6 axons and in vitro whole-cell recordings of the responses in VL neurons, we studied the individual responses as well as the effects of combined CN and M1-L6 stimulation. Whereas CN inputs evoked large-amplitude responses that were depressed upon repetitive stimulation, M1-L6 inputs elicited small-amplitude responses that were facilitated upon repetitive stimulation. Moreover, pauses in CN stimuli could directly affect VL spiking probability, an effect that was modulated by VL membrane potential. When CN and M1-L6 pathways were co-activated, motor cortical afferents increased the thalamic spike output in response to cerebellar stimulation, indicating that CN and M1 synergistically, yet differentially, control the membrane potential and spiking pattern of VL neurons.
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Affiliation(s)
| | - Zhenyu Gao
- Department of NeuroscienceErasmus MCRotterdam3015 AAThe Netherlands
| | - Chris I. De Zeeuw
- Department of NeuroscienceErasmus MCRotterdam3015 AAThe Netherlands
- Netherlands Institute for NeuroscienceRoyal Dutch Academy of Arts & ScienceAmsterdam1105 BAThe Netherlands
| | - Freek E. Hoebeek
- Department of NeuroscienceErasmus MCRotterdam3015 AAThe Netherlands
- Department for Developmental Origins of Disease, Wilhelmina Children's Hospital and Brain CenterUniversity Medical Center UtrechtUtrecht3584 EAThe Netherlands
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14
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Whitmire CJ, Liew YJ, Stanley GB. Thalamic state influences timing precision in the thalamocortical circuit. J Neurophysiol 2021; 125:1833-1850. [PMID: 33760642 DOI: 10.1152/jn.00261.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Sensory signals from the outside world are transduced at the periphery, passing through thalamus before reaching cortex, ultimately giving rise to the sensory representations that enable us to perceive the world. The thalamocortical circuit is particularly sensitive to the temporal precision of thalamic spiking due to highly convergent synaptic connectivity. Thalamic neurons can exhibit burst and tonic modes of firing that strongly influence timing within the thalamus. The impact of these changes in thalamic state on sensory encoding in the cortex, however, remains unclear. Here, we investigated the role of thalamic state on timing in the thalamocortical circuit of the vibrissa pathway in the anesthetized rat. We optogenetically hyperpolarized thalamus while recording single unit activity in both thalamus and cortex. Tonic spike-triggered analysis revealed temporally precise thalamic spiking that was locked to weak white-noise sensory stimuli, whereas thalamic burst spiking was associated with a loss in stimulus-locked temporal precision. These thalamic state-dependent changes propagated to cortex such that the cortical timing precision was diminished during the hyperpolarized (burst biased) thalamic state. Although still sensory driven, the cortical neurons became significantly less precisely locked to the weak white-noise stimulus. The results here suggests a state-dependent differential regulation of spike timing precision in the thalamus that could gate what signals are ultimately propagated to cortex.NEW & NOTEWORTHY The majority of sensory signals are transmitted through the thalamus. There is growing evidence of complex thalamic gating through coordinated firing modes that have a strong impact on cortical sensory representations. Optogenetic hyperpolarization of thalamus pushed it into burst firing that disrupted precise time-locked sensory signaling, with a direct impact on the downstream cortical encoding, setting the stage for a timing-based thalamic gate of sensory signaling.
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Affiliation(s)
- Clarissa J Whitmire
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia
| | - Yi Juin Liew
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.,Joint PhD Program in Biomedical Engineering, Georgia Institute of Technology-Emory University-Peking University, Atlanta, Georgia
| | - Garrett B Stanley
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia
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15
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The Cellular Electrophysiological Properties Underlying Multiplexed Coding in Purkinje Cells. J Neurosci 2021; 41:1850-1863. [PMID: 33452223 PMCID: PMC7939085 DOI: 10.1523/jneurosci.1719-20.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 12/03/2020] [Accepted: 12/10/2020] [Indexed: 12/01/2022] Open
Abstract
Neuronal firing patterns are crucial to underpin circuit level behaviors. In cerebellar Purkinje cells (PCs), both spike rates and pauses are used for behavioral coding, but the cellular mechanisms causing code transitions remain unknown. We use a well-validated PC model to explore the coding strategy that individual PCs use to process parallel fiber (PF) inputs. We find increasing input intensity shifts PCs from linear rate-coders to burst-pause timing-coders by triggering localized dendritic spikes. We validate dendritic spike properties with experimental data, elucidate spiking mechanisms, and predict spiking thresholds with and without inhibition. Both linear and burst-pause computations use individual branches as computational units, which challenges the traditional view of PCs as linear point neurons. Dendritic spike thresholds can be regulated by voltage state, compartmentalized channel modulation, between-branch interaction and synaptic inhibition to expand the dynamic range of linear computation or burst-pause computation. In addition, co-activated PF inputs between branches can modify somatic maximum spike rates and pause durations to make them carry analog signals. Our results provide new insights into the strategies used by individual neurons to expand their capacity of information processing. SIGNIFICANCE STATEMENT Understanding how neurons process information is a fundamental question in neuroscience. Purkinje cells (PCs) were traditionally regarded as linear point neurons. We used computational modeling to unveil their electrophysiological properties underlying the multiplexed coding strategy that is observed during behaviors. We demonstrate that increasing input intensity triggers localized dendritic spikes, shifting PCs from linear rate-coders to burst-pause timing-coders. Both coding strategies work at the level of individual dendritic branches. Our work suggests that PCs have the ability to implement branch-specific multiplexed coding at the cellular level, thereby increasing the capacity of cerebellar coding and learning.
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16
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Ishii T, Hosoya T. Interspike intervals within retinal spike bursts combinatorially encode multiple stimulus features. PLoS Comput Biol 2020; 16:e1007726. [PMID: 33156853 PMCID: PMC7738174 DOI: 10.1371/journal.pcbi.1007726] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 12/15/2020] [Accepted: 09/22/2020] [Indexed: 11/19/2022] Open
Abstract
Neurons in various regions of the brain generate spike bursts. While the number of spikes within a burst has been shown to carry information, information coding by interspike intervals (ISIs) is less well understood. In particular, a burst with k spikes has k−1 intraburst ISIs, and these k−1 ISIs could theoretically encode k−1 independent values. In this study, we demonstrate that such combinatorial coding occurs for retinal bursts. By recording ganglion cell spikes from isolated salamander retinae, we found that intraburst ISIs encode oscillatory light sequences that are much faster than the light intensity modulation encoded by the number of spikes. When a burst has three spikes, the two intraburst ISIs combinatorially encode the amplitude and phase of the oscillatory sequence. Analysis of trial-to-trial variability suggested that intraburst ISIs are regulated by two independent mechanisms responding to orthogonal oscillatory components, one of which is common to bursts with a different number of spikes. Therefore, the retina encodes multiple stimulus features by exploiting all degrees of freedom of burst spike patterns, i.e., the spike number and multiple intraburst ISIs. Neurons in various regions of the brain generate spike bursts. Bursts are typically composed of a few spikes generated within dozens of milliseconds, and individual bursts are separated by much longer periods of silence (~hundreds of milliseconds). Recent evidence indicates that the number of spikes in a burst, the interspike intervals (ISIs), and the overall duration of a burst, as well as the timing of burst onset, encode information. However, it remains unknown whether multiple ISIs within a single burst encode multiple input features. Here we demonstrate that such combinatorial ISI coding occurs for spike bursts in the retina. We recorded ganglion cell spikes from isolated salamander retinae stimulated with computer-generated movies. Visual response analyses indicated that multiple ISIs within a single burst combinatorially encode the phase and amplitude of oscillatory light sequences, which are different from the stimulus feature encoded by the spike number. The result demonstrates that the retina encodes multiple stimulus features by exploiting all degrees of freedom of burst spike patterns, i.e., the spike number and multiple intraburst ISIs. Because synaptic transmission in the visual system is highly sensitive to ISIs, the combinatorial ISI coding must have a major impact on visual information processing.
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Affiliation(s)
- Toshiyuki Ishii
- RIKEN Center for Brain Science and RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
- Toho University, Funabashi-shi, Chiba, Japan
- Department of Physiology, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
| | - Toshihiko Hosoya
- RIKEN Center for Brain Science and RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
- * E-mail:
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17
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Mukherjee A, Bajwa N, Lam NH, Porrero C, Clasca F, Halassa MM. Variation of connectivity across exemplar sensory and associative thalamocortical loops in the mouse. eLife 2020; 9:e62554. [PMID: 33103997 PMCID: PMC7644223 DOI: 10.7554/elife.62554] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 10/23/2020] [Indexed: 12/22/2022] Open
Abstract
The thalamus engages in sensation, action, and cognition, but the structure underlying these functions is poorly understood. Thalamic innervation of associative cortex targets several interneuron types, modulating dynamics and influencing plasticity. Is this structure-function relationship distinct from that of sensory thalamocortical systems? Here, we systematically compared function and structure across a sensory and an associative thalamocortical loop in the mouse. Enhancing excitability of mediodorsal thalamus, an associative structure, resulted in prefrontal activity dominated by inhibition. Equivalent enhancement of medial geniculate excitability robustly drove auditory cortical excitation. Structurally, geniculate axons innervated excitatory cortical targets in a preferential manner and with larger synaptic terminals, providing a putative explanation for functional divergence. The two thalamic circuits also had distinct input patterns, with mediodorsal thalamus receiving innervation from a diverse set of cortical areas. Altogether, our findings contribute to the emerging view of functional diversity across thalamic microcircuits and its structural basis.
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Affiliation(s)
- Arghya Mukherjee
- McGovern Institute for Brain ResearchCambridgeUnited States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Navdeep Bajwa
- McGovern Institute for Brain ResearchCambridgeUnited States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Norman H Lam
- McGovern Institute for Brain ResearchCambridgeUnited States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - César Porrero
- Department of Anatomy and Neuroscience, School of Medicine, Autónoma de Madrid UniversityMadridSpain
| | - Francisco Clasca
- Department of Anatomy and Neuroscience, School of Medicine, Autónoma de Madrid UniversityMadridSpain
| | - Michael M Halassa
- McGovern Institute for Brain ResearchCambridgeUnited States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
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18
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Ahn J, Phan HL, Cha S, Koo KI, Yoo Y, Goo YS. Synchrony of Spontaneous Burst Firing between Retinal Ganglion Cells Across Species. Exp Neurobiol 2020; 29:285-299. [PMID: 32921641 PMCID: PMC7492847 DOI: 10.5607/en20025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/27/2020] [Accepted: 08/31/2020] [Indexed: 01/16/2023] Open
Abstract
Neurons communicate with other neurons in response to environmental changes. Their goal is to transmit information to their targets reliably. A burst, which consists of multiple spikes within a short time interval, plays an essential role in enhancing the reliability of information transmission through synapses. In the visual system, retinal ganglion cells (RGCs), the output neurons of the retina, show bursting activity and transmit retinal information to the lateral geniculate neuron of the thalamus. In this study, to extend our interest to the population level, the burstings of multiple RGCs were simultaneously recorded using a multi-channel recording system. As the first step in network analysis, we focused on investigating the pairwise burst correlation between two RGCs. Furthermore, to assess if the population bursting is preserved across species, we compared the synchronized bursting of RGCs between marmoset monkey (callithrix jacchus), one species of the new world monkeys and mouse (C57BL/6J strain). First, monkey RGCs showed a larger number of spikes within a burst, while the inter-spike interval, burst duration, and inter-burst interval were smaller compared with mouse RGCs. Monkey RGCs showed a strong burst synchronization between RGCs, whereas mouse RGCs showed no correlated burst firing. Monkey RGC pairs showed significantly higher burst synchrony and mutual information than mouse RGC pairs did. Comprehensively, through this study, we emphasize that two species have a different bursting activity of RGCs and different burst synchronization suggesting two species have distinctive retinal processing.
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Affiliation(s)
- Jungryul Ahn
- Department of Physiology, Chungbuk National University School of Medicine, Cheongju 28644, Korea
| | - Huu Lam Phan
- Department of Biomedical Engineering, University of Ulsan, Ulsan 44610, Korea
| | - Seongkwang Cha
- Department of Physiology, Chungbuk National University School of Medicine, Cheongju 28644, Korea
| | - Kyo-In Koo
- Department of Biomedical Engineering, University of Ulsan, Ulsan 44610, Korea
| | - Yongseok Yoo
- Department of Electronics Engineering, Incheon National University, Incheon 22012, Korea
| | - Yong Sook Goo
- Department of Physiology, Chungbuk National University School of Medicine, Cheongju 28644, Korea
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19
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Ansorge J, Humanes‐Valera D, Pauzin FP, Schwarz MK, Krieger P. Cortical layer 6 control of sensory responses in higher‐order thalamus. J Physiol 2020; 598:3973-4001. [DOI: 10.1113/jp279915] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/22/2020] [Indexed: 12/29/2022] Open
Affiliation(s)
- Josephine Ansorge
- Faculty of Medicine, Department of Systems Neuroscience Ruhr University Bochum Bochum Germany
| | - Desire Humanes‐Valera
- Faculty of Medicine, Department of Systems Neuroscience Ruhr University Bochum Bochum Germany
| | - François P. Pauzin
- Faculty of Medicine, Department of Systems Neuroscience Ruhr University Bochum Bochum Germany
| | - Martin K. Schwarz
- Institute of Experimental Epileptology and Cognition Research University of Bonn Medical School Bonn Germany
| | - Patrik Krieger
- Faculty of Medicine, Department of Systems Neuroscience Ruhr University Bochum Bochum Germany
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20
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Cubero RJ, Marsili M, Roudi Y. Multiscale relevance and informative encoding in neuronal spike trains. J Comput Neurosci 2020; 48:85-102. [PMID: 31993923 PMCID: PMC7035307 DOI: 10.1007/s10827-020-00740-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 12/20/2019] [Accepted: 01/03/2020] [Indexed: 11/26/2022]
Abstract
Neuronal responses to complex stimuli and tasks can encompass a wide range of time scales. Understanding these responses requires measures that characterize how the information on these response patterns are represented across multiple temporal resolutions. In this paper we propose a metric - which we call multiscale relevance (MSR) - to capture the dynamical variability of the activity of single neurons across different time scales. The MSR is a non-parametric, fully featureless indicator in that it uses only the time stamps of the firing activity without resorting to any a priori covariate or invoking any specific structure in the tuning curve for neural activity. When applied to neural data from the mEC and from the ADn and PoS regions of freely-behaving rodents, we found that neurons having low MSR tend to have low mutual information and low firing sparsity across the correlates that are believed to be encoded by the region of the brain where the recordings were made. In addition, neurons with high MSR contain significant information on spatial navigation and allow to decode spatial position or head direction as efficiently as those neurons whose firing activity has high mutual information with the covariate to be decoded and significantly better than the set of neurons with high local variations in their interspike intervals. Given these results, we propose that the MSR can be used as a measure to rank and select neurons for their information content without the need to appeal to any a priori covariate.
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Affiliation(s)
- Ryan John Cubero
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
- The Abdus Salam International Center for Theoretical Physics, Trieste, Italy.
- Scuola Internazionale Superiore di Studi Avanzati, Trieste, Italy.
- IST Austria, Klosterneuburg, Austria.
| | - Matteo Marsili
- The Abdus Salam International Center for Theoretical Physics, Trieste, Italy
- Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Trieste, Italy
| | - Yasser Roudi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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21
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Abstract
The thalamus is a neural processor and integrator for the activities of the forebrain. Surprisingly, little is known about the roles of the "cerebellar" thalamus despite the anatomical observation that all the cortico-cerebello-cortical loops make relay in the main subnuclei of the thalamus. The thalamus displays a broad range of electrophysiological responses, such as neuronal spiking, bursting, or oscillatory rhythms, which contribute to precisely shape and to synchronize activities of cortical areas. We emphasize that the cerebellar thalamus deserves a renewal of interest to better understand its specific contributions to the cerebellar motor and associative functions, especially at a time where the anatomy between cerebellum and basal ganglia is being rewritten.
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22
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Park S, Sohn JW, Cho J, Huh Y. A Computational Modeling Reveals That Strength of Inhibitory Input, E/I Balance, and Distance of Excitatory Input Modulate Thalamocortical Bursting Properties. Exp Neurobiol 2019; 28:568-577. [PMID: 31698549 PMCID: PMC6844838 DOI: 10.5607/en.2019.28.5.568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/26/2019] [Accepted: 10/27/2019] [Indexed: 11/19/2022] Open
Abstract
The thalamus is a brain structure known to modulate sensory information before relaying to the cortex. The unique ability of a thalamocortical (TC) neuron to switch between the high frequency burst firing and single spike tonic firing has been implicated to have a key role in sensory modulation including pain. Of the two firing modes, burst firing, especially maintaining certain burst firing properties, was suggested to be critical in controlling nociceptive behaviors. Therefore, understanding the factors that influence burst firing properties would offer important insight into understanding sensory modulation. Using computational modeling, we investigated how the balance of excitatory and inhibitory inputs into a TC neuron influence TC bursting properties. We found that intensity of inhibitory inputs and the timing of excitatory input delivery control the dynamics of bursting properties. Then, to reflect a more realistic model, excitatory inputs delivered at different dendritic locations—proximal, intermediate, or distal—of a TC neuron were also investigated. Interestingly, excitatory input delivered into a distal dendrite, despite the furthest distance, had the strongest influence in shaping burst firing properties, suggesting that not all inputs equally contribute to modulating TC bursting properties. Overall, the results provide computational insights in understanding the detailed mechanism of the factors influencing temporal pattern of thalamic bursts.
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Affiliation(s)
- Sanggeon Park
- Department of Medical Science, College of Medicine, Catholic Kwandong University, Gangneung 25601, Korea.,Translational Brain Research Center, Catholic Kwandong University International St. Mary's Hospital, Incheon 22711, Korea.,Department of Neuroscience, University of Science & Technology, Daejeon 34113, Korea.,Center for Neuroscience, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Jeong-Woo Sohn
- Department of Medical Science, College of Medicine, Catholic Kwandong University, Gangneung 25601, Korea.,Translational Brain Research Center, Catholic Kwandong University International St. Mary's Hospital, Incheon 22711, Korea
| | - Jeiwon Cho
- Department of Medical Science, College of Medicine, Catholic Kwandong University, Gangneung 25601, Korea.,Translational Brain Research Center, Catholic Kwandong University International St. Mary's Hospital, Incheon 22711, Korea
| | - Yeowool Huh
- Department of Medical Science, College of Medicine, Catholic Kwandong University, Gangneung 25601, Korea.,Translational Brain Research Center, Catholic Kwandong University International St. Mary's Hospital, Incheon 22711, Korea
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23
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Pauzin FP, Krieger P. A Corticothalamic Circuit for Refining Tactile Encoding. Cell Rep 2019; 23:1314-1325. [PMID: 29719247 DOI: 10.1016/j.celrep.2018.03.128] [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: 10/31/2017] [Revised: 02/12/2018] [Accepted: 03/29/2018] [Indexed: 10/17/2022] Open
Abstract
A fundamental task for the brain is to determine which aspects of the continuous flow of information is the most relevant in a given behavioral situation. The information flow is regulated via dynamic interactions between feedforward and feedback pathways. One such pathway is via corticothalamic feedback. Layer 6 (L6) corticothalamic (CT) cells make both cortical and thalamic connections and, therefore, are key modulators of activity in both areas. The functional properties of L6 CT cells in sensory processing were investigated in the mouse whisker system. Optogenetic activation of L6 CT neurons decreased spontaneous spiking, with the net effect that a whisker-evoked response was more accurately detected (larger evoked-to-spontaneous spiking ratio) but at the expense of reducing the response probability. In addition, L6 CT activation decreases sensory adaptation in both the thalamus and cortex. L6 CT activity can thus tune the tactile system, depending on the behaviorally relevant tactile input.
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Affiliation(s)
- François Philippe Pauzin
- Department of Systems Neuroscience, Medical Faculty, Ruhr University Bochum, 44801 Bochum, Germany
| | - Patrik Krieger
- Department of Systems Neuroscience, Medical Faculty, Ruhr University Bochum, 44801 Bochum, Germany.
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24
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The Augmentation of Retinogeniculate Communication during Thalamic Burst Mode. J Neurosci 2019; 39:5697-5710. [PMID: 31109958 DOI: 10.1523/jneurosci.2320-18.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 05/09/2019] [Accepted: 05/10/2019] [Indexed: 11/21/2022] Open
Abstract
Retinal signals are transmitted to cortex via neurons in the lateral geniculate nucleus (LGN), where they are processed in burst or tonic response mode. Burst mode occurs when LGN neurons are sufficiently hyperpolarized for T-type Ca2+ channels to deinactivate, allowing them to open in response to depolarization, which can trigger a high-frequency sequence of Na+-based spikes (i.e., burst). In contrast, T-type channels are inactivated during tonic mode and do not contribute to spiking. Although burst mode is commonly associated with sleep and the disruption of retinogeniculate communication, bursts can also be triggered by visual stimulation, thereby transforming the retinal signals relayed to the cortex. To determine how burst mode affects retinogeniculate communication, we made recordings from monosynaptically connected retinal ganglion cells and LGN neurons in male/female cats during visual stimulation. Our results reveal a robust augmentation of retinal signals within the LGN during burst mode. Specifically, retinal spikes were more effective and often triggered multiple LGN spikes during periods likely to have increased T-type Ca2+ channel activity. Consistent with the biophysical properties of T-type Ca2+ channels, analysis revealed that effect magnitude was correlated with the duration of the preceding thalamic interspike interval and occurred even in the absence of classically defined bursts. Importantly, the augmentation of geniculate responses to retinal input was not associated with a degradation of visual signals. Together, these results indicate a graded nature of response mode and suggest that, under certain conditions, bursts facilitate the transmission of visual information to the cortex by amplifying retinal signals.SIGNIFICANCE STATEMENT The thalamus is the gateway for retinal information traveling to the cortex. The lateral geniculate nucleus, like all thalamic nuclei, has two classically defined categories of spikes-tonic and burst-that differ in their underlying cellular mechanisms. Here we compare retinogeniculate communication during burst and tonic response modes. Our results show that retinogeniculate communication is enhanced during burst mode and visually evoked thalamic bursts, thereby augmenting retinal signals transmitted to cortex. Further, our results demonstrate that the influence of burst mode on retinogeniculate communication is graded and can be measured even in the absence of classically defined thalamic bursts.
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25
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Abstract
The nervous system processes phenomenal amounts of information. This processing must be conducted efficiently. In telecommunications systems, efficiency is increased by transmitting multiple signals through a single communication channel, or multiplexing. Neurons also multiplex. Here, we demonstrate a strategy for multiplexing different features of aperiodic stimuli: Cortical neurons use the rate of asynchronous spiking to encode stimulus intensity while using the timing of synchronous spikes to encode abrupt changes in stimulus intensity. This is possible because high-contrast features (e.g., edges) evoke spikes that transiently synchronize across neurons, whereas low-contrast features evoke sustained asynchronous spiking whose rate is proportional to stimulus intensity. Differentially synchronized spiking evoked in the same neurons by different stimulus features enables the formation of multiplexed representations. Multiplexing refers to the simultaneous encoding of two or more signals. Neurons have been shown to multiplex, but different stimuli require different multiplexing strategies. Whereas the frequency and amplitude of periodic stimuli can be encoded by the timing and rate of the same spikes, natural scenes, which comprise areas over which intensity varies gradually and sparse edges where intensity changes abruptly, require a different multiplexing strategy. Recording in vivo from neurons in primary somatosensory cortex during tactile stimulation, we found that stimulus onset and offset (edges) evoked highly synchronized spiking, whereas other spikes in the same neurons occurred asynchronously. Stimulus intensity modulated the rate of asynchronous spiking, but did not affect the timing of synchronous spikes. From this, we hypothesized that spikes driven by high- and low-contrast stimulus features can be distinguished on the basis of their synchronization, and that differentially synchronized spiking can thus be used to form multiplexed representations. Applying a Bayesian decoding method, we verified that information about high- and low-contrast features can be recovered from an ensemble of model neurons receiving common input. Equally good decoding was achieved by distinguishing synchronous from asynchronous spikes and applying reverse correlation methods separately to each spike type. This result, which we verified with patch clamp recordings in vitro, demonstrates that neurons receiving common input can use the rate of asynchronous spiking to encode the intensity of low-contrast features while using the timing of synchronous spikes to encode the occurrence of high-contrast features. We refer to this strategy as synchrony-division multiplexing.
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26
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Madar AD, Ewell LA, Jones MV. Temporal pattern separation in hippocampal neurons through multiplexed neural codes. PLoS Comput Biol 2019; 15:e1006932. [PMID: 31009459 PMCID: PMC6476466 DOI: 10.1371/journal.pcbi.1006932] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 03/06/2019] [Indexed: 12/18/2022] Open
Abstract
Pattern separation is a central concept in current theories of episodic memory: this computation is thought to support our ability to avoid confusion between similar memories by transforming similar cortical input patterns of neural activity into dissimilar output patterns before their long-term storage in the hippocampus. Because there are many ways one can define patterns of neuronal activity and the similarity between them, pattern separation could in theory be achieved through multiple coding strategies. Using our recently developed assay that evaluates pattern separation in isolated tissue by controlling and recording the input and output spike trains of single hippocampal neurons, we explored neural codes through which pattern separation is performed by systematic testing of different similarity metrics and various time resolutions. We discovered that granule cells, the projection neurons of the dentate gyrus, can exhibit both pattern separation and its opposite computation, pattern convergence, depending on the neural code considered and the statistical structure of the input patterns. Pattern separation is favored when inputs are highly similar, and is achieved through spike time reorganization at short time scales (< 100 ms) as well as through variations in firing rate and burstiness at longer time scales. These multiplexed forms of pattern separation are network phenomena, notably controlled by GABAergic inhibition, that involve many celltypes with input-output transformations that participate in pattern separation to different extents and with complementary neural codes: a rate code for dentate fast-spiking interneurons, a burstiness code for hilar mossy cells and a synchrony code at long time scales for CA3 pyramidal cells. Therefore, the isolated hippocampal circuit itself is capable of performing temporal pattern separation using multiplexed coding strategies that might be essential to optimally disambiguate multimodal mnemonic representations.
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Affiliation(s)
- Antoine D. Madar
- Department of Neuroscience, University of Wisconsin-Madison, WI, United States of America
- Neuroscience Training Program, University of Wisconsin-Madison, WI, United States of America
- Department of Neurobiology, Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, IL, United States of America
| | - Laura A. Ewell
- Department of Neuroscience, University of Wisconsin-Madison, WI, United States of America
- Institute of Experimental Epileptology and Cognition Research, University of Bonn–Medical Center, Germany
| | - Mathew V. Jones
- Department of Neuroscience, University of Wisconsin-Madison, WI, United States of America
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Acute and Chronic Pain Processing in the Thalamocortical System of Humans and Animal Models. Neuroscience 2018; 387:58-71. [DOI: 10.1016/j.neuroscience.2017.09.042] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/24/2017] [Accepted: 09/24/2017] [Indexed: 02/07/2023]
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Abstract
The thalamus has long been suspected to have an important role in cognition, yet recent theories have favored a more corticocentric view. According to this view, the thalamus is an excitatory feedforward relay to or between cortical regions, and cognitively relevant computations are exclusively cortical. Here, we review anatomical, physiological, and behavioral studies along evolutionary and theoretical dimensions, arguing for essential and unique thalamic computations in cognition. Considering their architectural features as well as their ability to initiate, sustain, and switch cortical activity, thalamic circuits appear uniquely suited for computing contextual signals that rapidly reconfigure task-relevant cortical representations. We introduce a framework that formalizes this notion, show its consistency with several findings, and discuss its prediction of thalamic roles in perceptual inference and behavioral flexibility. Overall, our framework emphasizes an expanded view of the thalamus in cognitive computations and provides a roadmap to test several of its theoretical and experimental predictions.
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Affiliation(s)
- Rajeev V. Rikhye
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Ralf D. Wimmer
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Stanley Center for Psychiatric Genetics, Broad Institute, Cambridge, Massachusetts 02139, USA
| | - Michael M. Halassa
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Stanley Center for Psychiatric Genetics, Broad Institute, Cambridge, Massachusetts 02139, USA
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Zeldenrust F, Wadman WJ, Englitz B. Neural Coding With Bursts-Current State and Future Perspectives. Front Comput Neurosci 2018; 12:48. [PMID: 30034330 PMCID: PMC6043860 DOI: 10.3389/fncom.2018.00048] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 06/06/2018] [Indexed: 12/11/2022] Open
Abstract
Neuronal action potentials or spikes provide a long-range, noise-resistant means of communication between neurons. As point processes single spikes contain little information in themselves, i.e., outside the context of spikes from other neurons. Moreover, they may fail to cross a synapse. A burst, which consists of a short, high frequency train of spikes, will more reliably cross a synapse, increasing the likelihood of eliciting a postsynaptic spike, depending on the specific short-term plasticity at that synapse. Both the number and the temporal pattern of spikes in a burst provide a coding space that lies within the temporal integration realm of single neurons. Bursts have been observed in many species, including the non-mammalian, and in brain regions that range from subcortical to cortical. Despite their widespread presence and potential relevance, the uncertainties of how to classify bursts seems to have limited the research into the coding possibilities for bursts. The present series of research articles provides new insights into the relevance and interpretation of bursts across different neural circuits, and new methods for their analysis. Here, we provide a succinct introduction to the history of burst coding and an overview of recent work on this topic.
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Affiliation(s)
- Fleur Zeldenrust
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University, Nijmegen, Netherlands
| | - Wytse J Wadman
- Cellular and Systems Neurobiology Lab, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Bernhard Englitz
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University, Nijmegen, Netherlands
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Naud R, Sprekeler H. Sparse bursts optimize information transmission in a multiplexed neural code. Proc Natl Acad Sci U S A 2018; 115:E6329-E6338. [PMID: 29934400 PMCID: PMC6142200 DOI: 10.1073/pnas.1720995115] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Many cortical neurons combine the information ascending and descending the cortical hierarchy. In the classical view, this information is combined nonlinearly to give rise to a single firing-rate output, which collapses all input streams into one. We analyze the extent to which neurons can simultaneously represent multiple input streams by using a code that distinguishes spike timing patterns at the level of a neural ensemble. Using computational simulations constrained by experimental data, we show that cortical neurons are well suited to generate such multiplexing. Interestingly, this neural code maximizes information for short and sparse bursts, a regime consistent with in vivo recordings. Neurons can also demultiplex this information, using specific connectivity patterns. The anatomy of the adult mammalian cortex suggests that these connectivity patterns are used by the nervous system to maintain sparse bursting and optimal multiplexing. Contrary to firing-rate coding, our findings indicate that the physiology and anatomy of the cortex may be interpreted as optimizing the transmission of multiple independent signals to different targets.
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Affiliation(s)
- Richard Naud
- University of Ottawa Brain and Mind Research Institute, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada;
- Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Henning Sprekeler
- Bernstein Center for Computational Neuroscience Berlin, 10115 Berlin, Germany
- Modelling of Cognitive Processes, Institute of Software Engineering and Theoretical Computer Science, Technische Universität Berlin, 10587 Berlin, Germany
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Spike and burst coding in thalamocortical relay cells. PLoS Comput Biol 2018; 14:e1005960. [PMID: 29432418 PMCID: PMC5834212 DOI: 10.1371/journal.pcbi.1005960] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 03/02/2018] [Accepted: 01/08/2018] [Indexed: 11/19/2022] Open
Abstract
Mammalian thalamocortical relay (TCR) neurons switch their firing activity between a tonic spiking and a bursting regime. In a combined experimental and computational study, we investigated the features in the input signal that single spikes and bursts in the output spike train represent and how this code is influenced by the membrane voltage state of the neuron. Identical frozen Gaussian noise current traces were injected into TCR neurons in rat brain slices as well as in a validated three-compartment TCR model cell. The resulting membrane voltage traces and spike trains were analyzed by calculating the coherence and impedance. Reverse correlation techniques gave the Event-Triggered Average (ETA) and the Event-Triggered Covariance (ETC). This demonstrated that the feature selectivity started relatively long before the events (up to 300 ms) and showed a clear distinction between spikes (selective for fluctuations) and bursts (selective for integration). The model cell was fine-tuned to mimic the frozen noise initiated spike and burst responses to within experimental accuracy, especially for the mixed mode regimes. The information content carried by the various types of events in the signal as well as by the whole signal was calculated. Bursts phase-lock to and transfer information at lower frequencies than single spikes. On depolarization the neuron transits smoothly from the predominantly bursting regime to a spiking regime, in which it is more sensitive to high-frequency fluctuations. The model was then used to elucidate properties that could not be assessed experimentally, in particular the role of two important subthreshold voltage-dependent currents: the low threshold activated calcium current (IT) and the cyclic nucleotide modulated h current (Ih). The ETAs of those currents and their underlying activation/inactivation states not only explained the state dependence of the firing regime but also the long-lasting concerted dynamic action of the two currents. Finally, the model was used to investigate the more realistic “high-conductance state”, where fluctuations are caused by (synaptic) conductance changes instead of current injection. Under “standard” conditions bursts are difficult to initiate, given the high degree of inactivation of the T-type calcium current. Strong and/or precisely timed inhibitory currents were able to remove this inactivation. Neurons in the brain respond to (sensory) stimuli by generating electrical pulses called ‘spikes’ or ‘action potentials’. Spikes are organized in different temporal patterns, such as ‘bursts’ in which they occur at a high frequency followed by a period of silence. Bursts are ubiquitous in the nervous system: they occur in different parts of the brain and in different species. Different mechanisms that generate them have been pointed out. Why the nervous system uses bursts in its communication, or what type of information is represented by bursts, remains largely unknown. Here, we looked at bursting in thalamocortical relay (TCR) cells, neurons that form a bridge between early sensory processing and higher-order structures (cortex). These cells fire bursts as a result of the activation of two distinct subthreshold ionic currents: the T-type calcium current and the h-type current. We investigated experimentally and computationally what features in the input makes TCR cells respond with bursts, and what features with single spikes. Bursts are a response to low-frequency slowly increasing input; single spikes are a response to faster fluctuations. Moreover, bursts are rare and highly informative, in line with an earlier hypothesis that bursts could play a ‘wake-up call’ role in the nervous system.
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Kimura A, Imbe H. Robust Subthreshold Cross-modal Modulation of Auditory Response by Cutaneous Electrical Stimulation in First- and Higher-order Auditory Thalamic Nuclei. Neuroscience 2018; 372:161-180. [PMID: 29309880 DOI: 10.1016/j.neuroscience.2017.12.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 12/14/2017] [Accepted: 12/27/2017] [Indexed: 12/14/2022]
Abstract
Conventional extracellular recording has revealed cross-modal alterations of auditory cell activities by cutaneous electrical stimulation of the hindpaw in first- and higher-order auditory thalamic nuclei (Donishi et al., 2011). Juxta-cellular recording and labeling techniques were used in the present study to examine the cross-modal alterations in detail, focusing on possible nucleus and/or cell type-related distinctions in modulation. Recordings were obtained from 80 cells of anesthetized rats. Cutaneous electrical stimulation, which did not elicit unit discharges, i.e., subthreshold effects, modulated early (onset) and/or late auditory responses of first- (64%) and higher-order nucleus cells (77%) with regard to response magnitude, latency and/or burst spiking. Attenuation predominated in the modulation of response magnitude and burst spiking, and delay predominated in the modulation of response time. Striking alterations of burst spiking took place in higher-order nucleus cells, which had the potential to exhibit higher propensities for burst spiking as compared to first-order nucleus cells. A subpopulation of first-order nucleus cells showing modulation in early response magnitude in the caudal domain of the nucleus had larger cell bodies and higher propensities for burst spiking as compared to cells showing no modulation. These findings suggest that somatosensory influence is incorporated into parallel channels in auditory thalamic nuclei to impose distinct impacts on cortical and subcortical sensory processing. Further, cutaneous electrical stimulation given after early auditory responses modulated late responses. Somatosensory influence is likely to affect ongoing auditory processing at any time without being coincident with sound onset in a narrow temporal window.
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Affiliation(s)
- Akihisa Kimura
- Department of Physiology, Wakayama Medical University, Wakayama Kimiidera 811-1, 641-8509, Japan.
| | - Hiroki Imbe
- Department of Physiology, Wakayama Medical University, Wakayama Kimiidera 811-1, 641-8509, Japan
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33
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Halassa MM, Kastner S. Thalamic functions in distributed cognitive control. Nat Neurosci 2017; 20:1669-1679. [DOI: 10.1038/s41593-017-0020-1] [Citation(s) in RCA: 262] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Accepted: 08/27/2017] [Indexed: 01/08/2023]
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