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Courcelles EJ, Kjelsberg K, Convertino L, Nair RR, Witter MP, Nigro MJ. Association cortical areas in the mouse contain a large population of fast-spiking GABAergic neurons that do not express parvalbumin. Eur J Neurosci 2024; 59:3236-3255. [PMID: 38643976 DOI: 10.1111/ejn.16341] [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: 11/15/2023] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/23/2024]
Abstract
GABAergic neurons represent 10-15% of the neuronal population of the cortex but exert a powerful control over information flow in cortical circuits. The largest GABAergic class in the neocortex is represented by the parvalbumin-expressing fast-spiking neurons, which provide powerful somatic inhibition to their postsynaptic targets. Recently, the density of parvalbumin interneurons has been shown to be lower in associative areas of the mouse cortex as compared with sensory and motor areas. Modelling work based on these quantifications linked the low-density of parvalbumin interneurons with specific computations of associative cortices. However, it is still unknown whether the total GABAergic population of association cortices is smaller or whether another GABAergic type can compensate for the low density of parvalbumin interneurons. In the present study, we investigated these hypotheses using a combination of neuroanatomy, mouse genetics and neurophysiology. We found that the GABAergic population of association areas is comparable with that of primary sensory areas, and it is enriched of fast-spiking neurons that do not express parvalbumin and were not accounted for by previous quantifications. We developed an intersectional viral strategy to demonstrate that the population of fast-spiking neurons is comparable across cortical regions. Our results provide quantifications of the density of fast-spiking GABAergic neurons and offers new biological constrains to refine current models of cortical computations.
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Affiliation(s)
- Erik Justin Courcelles
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Kasper Kjelsberg
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Laura Convertino
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Rajeevkumar Raveendran Nair
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Menno P Witter
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Maximiliano José Nigro
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
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2
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Szegedi V, Bakos E, Furdan S, Kovács BH, Varga D, Erdélyi M, Barzó P, Szücs A, Tamás G, Lamsa K. HCN channels at the cell soma ensure the rapid electrical reactivity of fast-spiking interneurons in human neocortex. PLoS Biol 2023; 21:e3002001. [PMID: 36745683 PMCID: PMC9934405 DOI: 10.1371/journal.pbio.3002001] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 02/16/2023] [Accepted: 01/17/2023] [Indexed: 02/07/2023] Open
Abstract
Accumulating evidence indicates that there are substantial species differences in the properties of mammalian neurons, yet theories on circuit activity and information processing in the human brain are based heavily on results obtained from rodents and other experimental animals. This knowledge gap may be particularly important for understanding the neocortex, the brain area responsible for the most complex neuronal operations and showing the greatest evolutionary divergence. Here, we examined differences in the electrophysiological properties of human and mouse fast-spiking GABAergic basket cells, among the most abundant inhibitory interneurons in cortex. Analyses of membrane potential responses to current input, pharmacologically isolated somatic leak currents, isolated soma outside-out patch recordings, and immunohistochemical staining revealed that human neocortical basket cells abundantly express hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channel isoforms HCN1 and HCN2 at the cell soma membrane, whereas these channels are sparse at the rodent basket cell soma membrane. Antagonist experiments showed that HCN channels in human neurons contribute to the resting membrane potential and cell excitability at the cell soma, accelerate somatic membrane potential kinetics, and shorten the lag between excitatory postsynaptic potentials and action potential generation. These effects are important because the soma of human fast-spiking neurons without HCN channels exhibit low persistent ion leak and slow membrane potential kinetics, compared with mouse fast-spiking neurons. HCN channels speed up human cell membrane potential kinetics and help attain an input-output rate close to that of rodent cells. Computational modeling demonstrated that HCN channel activity at the human fast-spiking cell soma membrane is sufficient to accelerate the input-output function as observed in cell recordings. Thus, human and mouse fast-spiking neurons exhibit functionally significant differences in ion channel composition at the cell soma membrane to set the speed and fidelity of their input-output function. These HCN channels ensure fast electrical reactivity of fast-spiking cells in human neocortex.
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Affiliation(s)
- Viktor Szegedi
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Szeged, Hungary
- Hungarian Centre of Excellence for Molecular Medicine Research Group for Human neuron physiology and therapy, Szeged, Hungary
| | - Emőke Bakos
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Szeged, Hungary
- Hungarian Centre of Excellence for Molecular Medicine Research Group for Human neuron physiology and therapy, Szeged, Hungary
| | - Szabina Furdan
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Szeged, Hungary
- Hungarian Centre of Excellence for Molecular Medicine Research Group for Human neuron physiology and therapy, Szeged, Hungary
| | - Bálint H. Kovács
- Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary
| | - Dániel Varga
- Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary
| | - Miklós Erdélyi
- Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary
| | - Pál Barzó
- Department of Neurosurgery, University of Szeged, Szeged, Hungary
| | - Attila Szücs
- Hungarian Centre of Excellence for Molecular Medicine Research Group for Human neuron physiology and therapy, Szeged, Hungary
- Neuronal Cell Biology Research Group, Eötvös Loránd University, Budapest, Budapest, Hungary
| | - Gábor Tamás
- MTA-SZTE Research Group for Cortical Microcircuits, Department of Physiology, Anatomy and Neuroscience, University of Szeged, Szeged, Hungary
| | - Karri Lamsa
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Szeged, Hungary
- Hungarian Centre of Excellence for Molecular Medicine Research Group for Human neuron physiology and therapy, Szeged, Hungary
- * E-mail: ,
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3
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Jung K, Choi Y, Kwon HB. Cortical control of chandelier cells in neural codes. Front Cell Neurosci 2022; 16:992409. [PMID: 36299494 PMCID: PMC9588934 DOI: 10.3389/fncel.2022.992409] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/05/2022] [Indexed: 11/28/2022] Open
Abstract
Various cortical functions arise from the dynamic interplay of excitation and inhibition. GABAergic interneurons that mediate synaptic inhibition display significant diversity in cell morphology, electrophysiology, plasticity rule, and connectivity. These heterogeneous features are thought to underlie their functional diversity. Emerging attention on specific properties of the various interneuron types has emphasized the crucial role of cell-type specific inhibition in cortical neural processing. However, knowledge is still limited on how each interneuron type forms distinct neural circuits and regulates network activity in health and disease. To dissect interneuron heterogeneity at single cell-type precision, we focus on the chandelier cell (ChC), one of the most distinctive GABAergic interneuron types that exclusively innervate the axon initial segments (AIS) of excitatory pyramidal neurons. Here we review the current understanding of the structural and functional properties of ChCs and their implications in behavioral functions, network activity, and psychiatric disorders. These findings provide insights into the distinctive roles of various single-type interneurons in cortical neural coding and the pathophysiology of cortical dysfunction.
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4
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Nolan AL, Sohal VS, Rosi S. Selective Inhibitory Circuit Dysfunction after Chronic Frontal Lobe Contusion. J Neurosci 2022; 42:5361-5372. [PMID: 35610049 PMCID: PMC9270915 DOI: 10.1523/jneurosci.0097-22.2022] [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: 01/13/2022] [Revised: 05/12/2022] [Accepted: 05/17/2022] [Indexed: 01/09/2023] Open
Abstract
Traumatic brain injury (TBI) is a leading cause of neurologic disability; the most common deficits affect prefrontal cortex-dependent functions such as attention, working memory, social behavior, and mental flexibility. Despite this prevalence, little is known about the pathophysiology that develops in frontal cortical microcircuits after TBI. We investigated whether alterations in subtype-specific inhibitory circuits are associated with cognitive inflexibility in a mouse model of frontal lobe contusion in both male and female mice that recapitulates aberrant mental flexibility as measured by deficits in rule reversal learning. Using patch-clamp recordings and optogenetic stimulation, we identified selective vulnerability in the non-fast-spiking and somatostatin-expressing (SOM+) subtypes of inhibitory neurons in layer V of the orbitofrontal cortex 2 months after injury. These subtypes exhibited reduced intrinsic excitability and a decrease in their synaptic output onto pyramidal neurons, respectively. By contrast, the fast-spiking and parvalbumin-expressing interneurons did not show changes in intrinsic excitability or synaptic output, respectively. Impairments in non-fast-spiking/SOM+ inhibitory circuit function were also associated with network hyperexcitability. These findings provide evidence for selective disruptions within specific inhibitory microcircuits that may guide the development of novel therapeutics for TBI.SIGNIFICANCE STATEMENT TBI frequently leads to chronic deficits in cognitive and behavioral functions that involve the prefrontal cortex, yet the maladaptive changes that occur in these cortical microcircuits are unknown. Our data indicate that alterations in subtype-specific inhibitory circuits, specifically vulnerability in the non-fast-spiking/somatostatin-expressing interneurons, occurs in the orbitofrontal cortex in the context of chronic deficits in reversal learning. These neurons exhibit reduced excitability and synaptic output, whereas the other prominent inhibitory population in layer V, the fast-spiking/parvalbumin-expressing interneurons as well as pyramidal neurons are not affected. Our work offers mechanistic insight into the subtype-specific function of neurons that may contribute to mental inflexibility after TBI.
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Affiliation(s)
- Amber L Nolan
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington 98104
- Departments of Pathology
| | | | - Susanna Rosi
- Physical Therapy and Rehabilitation Science, University of California, San Francisco, San Francisco, California 94143
- Brain and Spinal Injury Center, University of California, San Francisco, San Francisco, California 94143
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California 94143
- Weill Institute for Neuroscience, University of California, San Francisco, San Francisco, California 94143
- Kavli Institute of Fundamental Neuroscience, University of California, San Francisco, San Francisco, California 94143
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5
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Nigro MJ, Kirikae H, Kjelsberg K, Nair RR, Witter MP. Not All That Is Gold Glitters: PV-IRES-Cre Mouse Line Shows Low Efficiency of Labeling of Parvalbumin Interneurons in the Perirhinal Cortex. Front Neural Circuits 2021; 15:781928. [PMID: 34819840 PMCID: PMC8606682 DOI: 10.3389/fncir.2021.781928] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 10/18/2021] [Indexed: 11/13/2022] Open
Abstract
The wide diversity of cortical inhibitory neuron types populating the cortex allows the assembly of diverse microcircuits and endows these circuits with different computational properties. Thus, characterizing neuronal diversity is fundamental to describe the building blocks of cortical microcircuits and probe their function. To this purpose, the mouse has emerged as a powerful tool to genetically label and manipulate specific inhibitory cell-types in the mammalian brain. Among these cell-types, the parvalbumin-expressing interneuron type (PV-INs) is perhaps the most characterized. Several mouse lines have been generated to target PV-INs. Among these mouse lines, the PV-IRES-Cre lines is the most widely used and demonstrated a high specificity and efficiency in targeting PV-INs in different cortical areas. However, a characterization of the performance across cortical regions is still missing. Here we show that the PV-IRES-Cre mouse line labels only a fraction of PV immunoreactive neurons in perirhinal cortex and other association areas. Our results point to a yet uncharacterized diversity within the PV-INs and emphasize the need to characterize these tools in specific cortical areas.
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Affiliation(s)
- Maximiliano José Nigro
- Center for Neural Computation, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Hinako Kirikae
- Center for Neural Computation, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.,Department of Organ Anatomy, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Kasper Kjelsberg
- Center for Neural Computation, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Rajeevkumar Raveendran Nair
- Center for Neural Computation, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Menno P Witter
- Center for Neural Computation, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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6
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Binini N, Talpo F, Spaiardi P, Maniezzi C, Pedrazzoli M, Raffin F, Mattiello N, Castagno AN, Masetto S, Yanagawa Y, Dickson CT, Ramat S, Toselli M, Biella GR. Membrane Resonance in Pyramidal and GABAergic Neurons of the Mouse Perirhinal Cortex. Front Cell Neurosci 2021; 15:703407. [PMID: 34366789 PMCID: PMC8339929 DOI: 10.3389/fncel.2021.703407] [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: 04/30/2021] [Accepted: 06/16/2021] [Indexed: 11/13/2022] Open
Abstract
The perirhinal cortex (PRC) is a polymodal associative region of the temporal lobe that works as a gateway between cortical areas and hippocampus. In recent years, an increasing interest arose in the role played by the PRC in learning and memory processes, such as object recognition memory, in contrast with certain forms of hippocampus-dependent spatial and episodic memory. The integrative properties of the PRC should provide all necessary resources to select and enhance the information to be propagated to and from the hippocampus. Among these properties, we explore in this paper the ability of the PRC neurons to amplify the output voltage to current input at selected frequencies, known as membrane resonance. Within cerebral circuits the resonance of a neuron operates as a filter toward inputs signals at certain frequencies to coordinate network activity in the brain by affecting the rate of neuronal firing and the precision of spike timing. Furthermore, the ability of the PRC neurons to resonate could have a fundamental role in generating subthreshold oscillations and in the selection of cortical inputs directed to the hippocampus. Here, performing whole-cell patch-clamp recordings from perirhinal pyramidal neurons and GABAergic interneurons of GAD67-GFP+ mice, we found, for the first time, that the majority of PRC neurons are resonant at their resting potential, with a resonance frequency of 0.5–1.5 Hz at 23°C and of 1.5–2.8 Hz at 36°C. In the presence of ZD7288 (blocker of HCN channels) resonance was abolished in both pyramidal neurons and interneurons, suggesting that Ih current is critically involved in resonance generation. Otherwise, application of TTx (voltage-dependent Na+ channel blocker) attenuates the resonance in pyramidal neurons but not in interneurons, suggesting that only in pyramidal neurons the persistent sodium current has an amplifying effect. These experimental results have also been confirmed by a computational model. From a functional point of view, the resonance in the PRC would affect the reverberating activity between neocortex and hippocampus, especially during slow wave sleep, and could be involved in the redistribution and strengthening of memory representation in cortical regions.
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Affiliation(s)
- Noemi Binini
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Francesca Talpo
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Paolo Spaiardi
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Claudia Maniezzi
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Matteo Pedrazzoli
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Francesca Raffin
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Niccolò Mattiello
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Antonio N Castagno
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Sergio Masetto
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University, Maebashi, Japan
| | - Clayton T Dickson
- Department of Psychology, University of Alberta, Edmonton, AB, Canada
| | - Stefano Ramat
- Department of Industrial and Information Engineering, University of Pavia, Pavia, Italy
| | - Mauro Toselli
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
| | - Gerardo Rosario Biella
- Department of Biology and Biotechnology Lazzaro Spallanzani, University of Pavia, Pavia, Italy
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7
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Yiannakas A, Kolatt Chandran S, Kayyal H, Gould N, Khamaisy M, Rosenblum K. Parvalbumin interneuron inhibition onto anterior insula neurons projecting to the basolateral amygdala drives aversive taste memory retrieval. Curr Biol 2021; 31:2770-2784.e6. [PMID: 33930301 DOI: 10.1016/j.cub.2021.04.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 12/08/2020] [Accepted: 04/07/2021] [Indexed: 12/12/2022]
Abstract
Memory retrieval refers to the fundamental ability of organisms to make use of acquired, sometimes inconsistent, information about the world. Although memory acquisition has been studied extensively, the neurobiological mechanisms underlying memory retrieval remain largely unknown. Conditioned taste aversion (CTA) is a robust associative paradigm, through which animals can be trained to express aversion toward innately appetitive tastants. The anterior insula (aIC) is indispensable in the ability of mammals to retrieve associative information regarding tastants that have been previously linked with gastric malaise. Here, we show that CTA memory retrieval promotes cell-type-specific activation in the aIC. Using chemogenetic tools in the aIC, we found that CTA memory acquisition requires activation of excitatory neurons and inhibition of inhibitory neurons, whereas retrieval necessitates activation of both excitatory and inhibitory aIC circuits. CTA memory retrieval at the aIC activates parvalbumin (PV) interneurons and increases synaptic inhibition onto activated pyramidal neurons projecting to the basolateral amygdala (aIC-BLA). Unlike innately appetitive taste memory retrieval, CTA retrieval increases synaptic inhibition onto aIC-BLA-projecting neurons that is dependent on activity in aIC PV interneurons. PV aIC interneurons coordinate CTA memory retrieval and are necessary for its dominance when conflicting internal representations are encountered over time. The reinstatement of CTA memories following extinction is also dependent on activation of aIC PV interneurons, which increase the frequency of inhibition onto aIC-BLA-projecting neurons. This newly described interaction of PV and a subset of excitatory neurons can explain the coherency of aversive memory retrieval, an evolutionary pre-requisite for animal survival.
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Affiliation(s)
- Adonis Yiannakas
- Sagol Department of Neuroscience, University of Haifa, Mount Carmel, Haifa, Israel.
| | | | - Haneen Kayyal
- Sagol Department of Neuroscience, University of Haifa, Mount Carmel, Haifa, Israel
| | - Nathaniel Gould
- Sagol Department of Neuroscience, University of Haifa, Mount Carmel, Haifa, Israel
| | - Mohammad Khamaisy
- Sagol Department of Neuroscience, University of Haifa, Mount Carmel, Haifa, Israel
| | - Kobi Rosenblum
- Sagol Department of Neuroscience, University of Haifa, Mount Carmel, Haifa, Israel; Center for Gene Manipulation in the Brain, University of Haifa, Mount Carmel, Haifa, Israel.
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8
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Kajiwara R, Tominaga T. Perirhinal cortex area 35 controls the functional link between the perirhinal and entorhinal-hippocampal circuitry: D-type potassium channel-mediated gating of neural propagation from the perirhinal cortex to the entorhinal-hippocampal circuitry. Bioessays 2020; 43:e2000084. [PMID: 33236360 DOI: 10.1002/bies.202000084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 10/15/2020] [Accepted: 10/15/2020] [Indexed: 11/07/2022]
Abstract
In several experimental conditions, neuronal excitation at the perirhinal cortex (PC) does not propagate to the entorhinal cortex (EC) due to a "wall" of inhibition, which may help to create functional coupling and un-coupling of the PC and EC in the medial temporal lobe. However, little is known regarding the coupling control process. Herein, we propose that the deep layer of area 35 in the PC plays a pivotal role in opening the gate for coupling, thus allowing the activity in the PC to propagate to the EC. Using voltage-sensitive dye imaging for the brain slices of rodents, we show that a slowly inactivating potassium conductance in this area is essential to induce excitation overtaking the inhibitory control. This coupling between the distinct neural circuits persists for at least 1 h. We elucidate further implications of this network-level plastic behavior and its mechanism.
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Affiliation(s)
- Riichi Kajiwara
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kawasaki, Japan
| | - Takashi Tominaga
- Laboratory for Neural Circuit Systems, Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
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9
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Hahn A, Pensold D, Bayer C, Tittelmeier J, González-Bermúdez L, Marx-Blümel L, Linde J, Groß J, Salinas-Riester G, Lingner T, von Maltzahn J, Spehr M, Pieler T, Urbach A, Zimmer-Bensch G. DNA Methyltransferase 1 (DNMT1) Function Is Implicated in the Age-Related Loss of Cortical Interneurons. Front Cell Dev Biol 2020; 8:639. [PMID: 32793592 PMCID: PMC7387673 DOI: 10.3389/fcell.2020.00639] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 06/25/2020] [Indexed: 01/19/2023] Open
Abstract
Increased life expectancy in modern society comes at the cost of age-associated disabilities and diseases. Aged brains not only show reduced excitability and plasticity, but also a decline in inhibition. Age-associated defects in inhibitory circuits likely contribute to cognitive decline and age-related disorders. Molecular mechanisms that exert epigenetic control of gene expression contribute to age-associated neuronal impairments. Both DNA methylation, mediated by DNA methyltransferases (DNMTs), and histone modifications maintain neuronal function throughout lifespan. Here we provide evidence that DNMT1 function is implicated in the age-related loss of cortical inhibitory interneurons. Dnmt1 deletion in parvalbumin-positive interneurons attenuates their age-related decline in the cerebral cortex. Moreover, conditional Dnmt1-deficient mice show improved somatomotor performance and reduced aging-associated transcriptional changes. A decline in the proteostasis network, responsible for the proper degradation and removal of defective proteins, is implicated in age- and disease-related neurodegeneration. Our data suggest that DNMT1 acts indirectly on interneuron survival in aged mice by modulating the proteostasis network during life-time.
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Affiliation(s)
- Anne Hahn
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany
| | - Daniel Pensold
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany.,Department of Functional Epigenetics in the Animal Model, Institute of Biology II, RWTH Aachen University, Aachen, Germany
| | - Cathrin Bayer
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany.,Department of Functional Epigenetics in the Animal Model, Institute of Biology II, RWTH Aachen University, Aachen, Germany
| | - Jessica Tittelmeier
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany
| | - Lourdes González-Bermúdez
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany
| | - Lisa Marx-Blümel
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany
| | - Jenice Linde
- Department of Functional Epigenetics in the Animal Model, Institute of Biology II, RWTH Aachen University, Aachen, Germany.,Research Training Group 2416 MultiSenses - MultiScales, RWTH Aachen University, Aachen, Germany
| | - Jonas Groß
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany
| | - Gabriela Salinas-Riester
- Transcriptome and Genome Analysis Laboratory (TAL), Department of Developmental Biochemistry, University of Göttingen, Göttingen, Germany
| | - Thomas Lingner
- Transcriptome and Genome Analysis Laboratory (TAL), Department of Developmental Biochemistry, University of Göttingen, Göttingen, Germany
| | - Julia von Maltzahn
- Leibniz Institute on Aging - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Marc Spehr
- Research Training Group 2416 MultiSenses - MultiScales, RWTH Aachen University, Aachen, Germany.,Department of Chemosensation, Institute of Biology II, RWTH Aachen University, Aachen, Germany
| | - Tomas Pieler
- Centre for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Department of Developmental Biochemistry, University of Göttingen, Göttingen, Germany
| | - Anja Urbach
- Institute of Neurology, University Hospital Jena, Jena, Germany
| | - Geraldine Zimmer-Bensch
- Department of Functional Epigenetics, Institute of Human Genetics, University Hospital Jena, Jena, Germany.,Department of Functional Epigenetics in the Animal Model, Institute of Biology II, RWTH Aachen University, Aachen, Germany.,Research Training Group 2416 MultiSenses - MultiScales, RWTH Aachen University, Aachen, Germany
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10
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The medial prefrontal cortex - hippocampus circuit that integrates information of object, place and time to construct episodic memory in rodents: Behavioral, anatomical and neurochemical properties. Neurosci Biobehav Rev 2020; 113:373-407. [PMID: 32298711 DOI: 10.1016/j.neubiorev.2020.04.007] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 02/25/2020] [Accepted: 04/06/2020] [Indexed: 12/31/2022]
Abstract
Rats and mice have been demonstrated to show episodic-like memory, a prototype of episodic memory, as defined by an integrated memory of the experience of an object or event, in a particular place and time. Such memory can be assessed via the use of spontaneous object exploration paradigms, variably designed to measure memory for object, place, temporal order and object-location inter-relationships. We review the methodological properties of these tests, the neurobiology about time and discuss the evidence for the involvement of the medial prefrontal cortex (mPFC), entorhinal cortex (EC) and hippocampus, with respect to their anatomy, neurotransmitter systems and functional circuits. The systematic analysis suggests that a specific circuit between the mPFC, lateral EC and hippocampus encodes the information for event, place and time of occurrence into the complex episodic-like memory, as a top-down regulation from the mPFC onto the hippocampus. This circuit can be distinguished from the neuronal component memory systems for processing the individual information of object, time and place.
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Sanchez-Mejias E, Nuñez-Diaz C, Sanchez-Varo R, Gomez-Arboledas A, Garcia-Leon JA, Fernandez-Valenzuela JJ, Mejias-Ortega M, Trujillo-Estrada L, Baglietto-Vargas D, Moreno-Gonzalez I, Davila JC, Vitorica J, Gutierrez A. Distinct disease-sensitive GABAergic neurons in the perirhinal cortex of Alzheimer's mice and patients. Brain Pathol 2019; 30:345-363. [PMID: 31491047 PMCID: PMC7064898 DOI: 10.1111/bpa.12785] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 09/02/2019] [Indexed: 12/29/2022] Open
Abstract
Neuronal loss is the best neuropathological substrate that correlates with cortical atrophy and dementia in Alzheimer's disease (AD). Defective GABAergic neuronal functions may lead to cortical network hyperactivity and aberrant neuronal oscillations and in consequence, generate a detrimental alteration in memory processes. In this study, using immunohistochemical and stereological approaches, we report that the two major and non-overlapping groups of inhibitory interneurons (SOM-cells and PV-cells) displayed distinct vulnerability in the perirhinal cortex of APP/PS1 mice and AD patients. SOM-positive neurons were notably sensitive and exhibited a dramatic decrease in the perirhinal cortex of 6-month-old transgenic mice (57% and 61% in areas 36 and 35, respectively) and, most importantly, in AD patients (91% in Braak V-VI cases). In addition, this interneuron degenerative process seems to occur in parallel, and closely related, with the progression of the amyloid pathology. However, the population expressing PV was unaffected in APP/PS1 mice while in AD brains suffered a pronounced and significant loss (69%). As a key component of cortico-hippocampal networks, the perirhinal cortex plays an important role in memory processes, especially in familiarity-based memory recognition. Therefore, disrupted functional connectivity of this cortical region, as a result of the early SOM and PV neurodegeneration, might contribute to the altered brain rhythms and cognitive failures observed in the initial clinical phase of AD patients. Finally, these findings highlight the failure of amyloidogenic AD models to fully recapitulate the selective neuronal degeneration occurring in humans.
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Affiliation(s)
- Elisabeth Sanchez-Mejias
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Cristina Nuñez-Diaz
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Raquel Sanchez-Varo
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Angela Gomez-Arboledas
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Juan Antonio Garcia-Leon
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Juan Jose Fernandez-Valenzuela
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Marina Mejias-Ortega
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Laura Trujillo-Estrada
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - David Baglietto-Vargas
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Ines Moreno-Gonzalez
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Jose Carlos Davila
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Javier Vitorica
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Dpto. Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Sevilla, Spain.,Instituto de Biomedicina de Sevilla (IBIS)-Hospital Universitario Virgen del Rocio/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Antonia Gutierrez
- Dpto. Biología Celular, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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12
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Interaction of Cortical and Amygdalar Synaptic Input Modulates the Window of Opportunity for Information Processing in the Rhinal Cortices. eNeuro 2019; 6:ENEURO.0020-19.2019. [PMID: 31387874 PMCID: PMC6712206 DOI: 10.1523/eneuro.0020-19.2019] [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: 01/16/2019] [Revised: 06/12/2019] [Accepted: 07/19/2019] [Indexed: 11/24/2022] Open
Abstract
The perirhinal (PER) and lateral entorhinal (LEC) cortex function as a gateway for information transmission between (sub)cortical areas and the hippocampus. It is hypothesized that the amygdala, a key structure in emotion processing, can modulate PER-LEC neuronal activity before information enters the hippocampal memory pathway. This study determined the integration of synaptic activity evoked by simultaneous neocortical and amygdala electrical stimulation in PER-LEC deep layer principal neurons and parvalbumin (PV) interneurons in mouse brain slices. The data revealed that both deep layer PER-LEC principal neurons and PV interneurons receive synaptic input from the neocortical agranular insular cortex (AiP) and the lateral amygdala (LA). Furthermore, simultaneous stimulation of the AiP and LA never reached the firing threshold in principal neurons of the PER-LEC deep layers. PV interneurons however, mainly showed linear summation of simultaneous AiP and LA inputs and reached their firing threshold earlier. This early PV firing was reflected in the forward shift of the evoked inhibitory conductance in principal neurons, thereby creating a more precise temporal window for coincidence detection, which likely plays a crucial role in information processing.
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13
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Willems JGP, Wadman WJ, Cappaert NLM. Excitation-Inhibition Dynamics Regulate Activity Transmission Through the Perirhinal-Entorhinal Network. Neuroscience 2019; 411:222-236. [PMID: 31132396 DOI: 10.1016/j.neuroscience.2019.05.031] [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: 12/07/2018] [Revised: 04/05/2019] [Accepted: 05/17/2019] [Indexed: 10/26/2022]
Abstract
The perirhinal (PER) - lateral entorhinal (LEC) network plays a pivotal role in the information transfer between the neocortex and the hippocampus. Anatomical studies have shown that the connectivity is organized bi-directionally: the superficial layers consist of projections running from the neocortex via the PER-LEC network to the hippocampus while the deep layers form the output pathway back to the neocortex. Although these pathways are characterized anatomically, the functional organization of the superficial and deep connections in the PER-LEC network remains to be revealed. We performed paired recordings of superficial and deep layer principal neurons and found that a larger population of superficial neurons responded with action potential firing in response to superficial cortical input, compared to the deep layer population. This suggested that the superficial network can carry information from the cortex towards the hippocampus. The relation between the excitatory and inhibitory input onto the deep and superficial principal neurons showed that the window of net excitability was larger in superficial principal neurons. We performed paired recordings in superficial layer principal neurons and parvalbumin (PV) expressing interneurons to address how this window of opportunity for spiking is affected in superficial principal neurons. The PV interneuron population initiated inhibition at a very consistent timing with increasing stimulus intensity, whereas the excitation temporally shifted to ensure action potential firing. These data indicate that superficial principal neurons can transmit cortical synaptic input through the PER-LEC network because these neurons have a favorable window of opportunity for spiking in contrast to deep neurons.
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Affiliation(s)
- Janske G P Willems
- Center for NeuroScience, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands
| | - Wytse J Wadman
- Center for NeuroScience, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands
| | - Natalie L M Cappaert
- Center for NeuroScience, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands.
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Kajiwara R, Tominaga Y, Tominaga T. Network Plasticity Involved in the Spread of Neural Activity Within the Rhinal Cortices as Revealed by Voltage-Sensitive Dye Imaging in Mouse Brain Slices. Front Cell Neurosci 2019; 13:20. [PMID: 30804757 PMCID: PMC6378919 DOI: 10.3389/fncel.2019.00020] [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: 09/09/2018] [Accepted: 01/16/2019] [Indexed: 11/13/2022] Open
Abstract
The rhinal cortices, such as the perirhinal cortex (PC) and the entorhinal cortex (EC), are located within the bidirectional pathway between the neocortex and the hippocampus. Physiological studies indicate that the perirhinal transmission of neocortical inputs to the EC occurs at an extremely low probability, though many anatomical studies indicated strong connections exist in the pathway. Our previous study in rat brain slices indicated that an increase in excitability in deep layers of the PC/EC border initiated the neural activity transfer from the PC to the EC. In the present study, we hypothesized that such changes in network dynamics are not incidental observations but rather due to the plastic features of the perirhinal network, which links with the EC. To confirm this idea, we analyzed the network properties of neural transmission throughout the rhinal cortices and the plastic behavior of the network by performing a single-photon wide-field optical recording technique with a voltage-sensitive dye (VSD) in mouse brain slices of the PC, the EC, and the hippocampus. The low concentration of 4-aminopyridine (4-AP; 40 μM) enhanced neural activity in the PC, which eventually propagated to the EC via the deep layers of the PC/EC border. Interestingly, washout of 4-AP was unable to reverse entorhinal activation to the previous state. This change in the network property persisted for more than 1 h. This observation was not limited to the application of 4-AP. Burst stimulation to neurons in the perirhinal deep layers also induced the same change of network property. These results indicate the long-lasting modification of physiological connection between the PC and the EC, suggesting the existence of plasticity in the perirhinal-entorhinal network.
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Affiliation(s)
- Riichi Kajiwara
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kawasaki, Japan
| | - Yoko Tominaga
- Laboratory for Neural Circuit Systems, Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
| | - Takashi Tominaga
- Laboratory for Neural Circuit Systems, Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
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15
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Adult vitamin D deficiency disrupts hippocampal-dependent learning and structural brain connectivity in BALB/c mice. Brain Struct Funct 2019; 224:1315-1329. [PMID: 30712221 DOI: 10.1007/s00429-019-01840-w] [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: 08/20/2018] [Accepted: 01/22/2019] [Indexed: 12/17/2022]
Abstract
Converging evidence from human and animal studies support an association between vitamin D deficiency and cognitive impairment. Previous studies have shown that hippocampal volume is reduced in adults with vitamin D deficiency as well as in a range of disorders, such as schizophrenia. The aim of the current study was to examine the effect of adult vitamin D (AVD) deficiency on hippocampal-dependent spatial learning, and hippocampal volume and connectivity in healthy adult mice. Ten-week-old male BALB/c mice were fed a control (vitamin D 1500 IU/kg) or vitamin D-depleted (vitamin D 0 IU/kg) diet for a minimum of 10 weeks. The mice were then tested for hippocampal-dependent spatial learning using active place avoidance (APA) and on tests of muscle and motor coordination (rotarod and grip strength). The mice were perfused and brains collected to acquire ex vivo structural and diffusion-weighted images using a 16.4 T MRI scanner. We also performed immunohistochemistry to quantify perineuronal nets (PNNs) and parvalbumin (PV) interneurons in various brain regions. AVD-deficient mice had a lower latency to enter the shock zone on APA, compared to control mice, suggesting impaired hippocampal-dependent spatial learning. There were no differences in rotarod or grip strength, indicating that AVD deficiency did not have an impact on muscle or motor coordination. AVD deficiency did not have an impact on hippocampal volume. However, AVD-deficient mice displayed a disrupted network centred on the right hippocampus with abnormal connectomes among 29 nodes. We found a reduction in PNN positive cells, but no change in PV, centred on the hippocampus. Our results provide compelling evidence to show that AVD deficiency in otherwise healthy adult mice may play a key role in hippocampal-dependent learning and memory formation. We suggest that the spatial learning deficits could be due to the disruption of right hippocampal structural connectivity.
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16
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Serotonin receptor 2c-expressing cells in the ventral CA1 control attention via innervation of the Edinger–Westphal nucleus. Nat Neurosci 2018; 21:1239-1250. [DOI: 10.1038/s41593-018-0207-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 06/24/2018] [Indexed: 11/09/2022]
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17
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Willems JGP, Wadman WJ, Cappaert NLM. Parvalbumin interneuron mediated feedforward inhibition controls signal output in the deep layers of the perirhinal-entorhinal cortex. Hippocampus 2018; 28:281-296. [PMID: 29341361 PMCID: PMC5900730 DOI: 10.1002/hipo.22830] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 01/03/2018] [Accepted: 01/08/2018] [Indexed: 11/11/2022]
Abstract
The perirhinal (PER) and lateral entorhinal (LEC) cortex form an anatomical link between the neocortex and the hippocampus. However, neocortical activity is transmitted through the PER and LEC to the hippocampus with a low probability, suggesting the involvement of the inhibitory network. This study explored the role of interneuron mediated inhibition, activated by electrical stimulation in the agranular insular cortex (AiP), in the deep layers of the PER and LEC. Activated synaptic input by AiP stimulation rarely evoked action potentials in the PER‐LEC deep layer excitatory principal neurons, most probably because the evoked synaptic response consisted of a small excitatory and large inhibitory conductance. Furthermore, parvalbumin positive (PV) interneurons—a subset of interneurons projecting onto the axo‐somatic region of principal neurons—received synaptic input earlier than principal neurons, suggesting recruitment of feedforward inhibition. This synaptic input in PV interneurons evoked varying trains of action potentials, explaining the fast rising, long lasting synaptic inhibition received by deep layer principal neurons. Altogether, the excitatory input from the AiP onto deep layer principal neurons is overruled by strong feedforward inhibition. PV interneurons, with their fast, extensive stimulus‐evoked firing, are able to deliver this fast evoked inhibition in principal neurons. This indicates an essential role for PV interneurons in the gating mechanism of the PER‐LEC network.
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Affiliation(s)
- Janske G P Willems
- Center for Neuroscience, Sammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, Amsterdam 1098 XH, The Netherlands
| | - Wytse J Wadman
- Center for Neuroscience, Sammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, Amsterdam 1098 XH, The Netherlands
| | - Natalie L M Cappaert
- Center for Neuroscience, Sammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, Amsterdam 1098 XH, The Netherlands
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