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Bennett HC, Zhang Q, Wu YT, Manjila SB, Chon U, Shin D, Vanselow DJ, Pi HJ, Drew PJ, Kim Y. Aging drives cerebrovascular network remodeling and functional changes in the mouse brain. Nat Commun 2024; 15:6398. [PMID: 39080289 PMCID: PMC11289283 DOI: 10.1038/s41467-024-50559-8] [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: 06/09/2023] [Accepted: 07/15/2024] [Indexed: 08/02/2024] Open
Abstract
Aging is frequently associated with compromised cerebrovasculature and pericytes. However, we do not know how normal aging differentially impacts vascular structure and function in different brain areas. Here we utilize mesoscale microscopy methods and in vivo imaging to determine detailed changes in aged murine cerebrovascular networks. Whole-brain vascular tracing shows an overall ~10% decrease in vascular length and branching density with ~7% increase in vascular radii in aged brains. Light sheet imaging with 3D immunolabeling reveals increased arteriole tortuosity of aged brains. Notably, vasculature and pericyte densities show selective and significant reductions in the deep cortical layers, hippocampal network, and basal forebrain areas. We find increased blood extravasation, implying compromised blood-brain barrier function in aged brains. Moreover, in vivo imaging in awake mice demonstrates reduced baseline and on-demand blood oxygenation despite relatively intact neurovascular coupling. Collectively, we uncover regional vulnerabilities of cerebrovascular network and physiological changes that can mediate cognitive decline in normal aging.
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Affiliation(s)
- Hannah C Bennett
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Qingguang Zhang
- Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physiology, Michigan State University, East Lansing, MI, 48824, USA
| | - Yuan-Ting Wu
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
- Department of Neurosurgery, Department of Computational Biomedicine, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Steffy B Manjila
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Uree Chon
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
- Neurosciences Graduate Program, Stanford University, Stanford, CA, 94305, USA
| | - Donghui Shin
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Daniel J Vanselow
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Hyun-Jae Pi
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Patrick J Drew
- Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Biomedical Engineering, Biology, and Neurosurgery, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Yongsoo Kim
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA.
- Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA.
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2
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Martinetti LE, Autio DM, Crandall SR. Motor Control of Distinct Layer 6 Corticothalamic Feedback Circuits. eNeuro 2024; 11:ENEURO.0255-24.2024. [PMID: 38926084 PMCID: PMC11236587 DOI: 10.1523/eneuro.0255-24.2024] [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: 06/11/2024] [Accepted: 06/20/2024] [Indexed: 06/28/2024] Open
Abstract
Layer 6 corticothalamic (L6 CT) neurons provide massive input to the thalamus, and these feedback connections enable the cortex to influence its own sensory input by modulating thalamic excitability. However, the functional role(s) feedback serves during sensory processing is unclear. One hypothesis is that CT feedback is under the control of extrasensory signals originating from higher-order cortical areas, yet we know nothing about the mechanisms of such control. It is also unclear whether such regulation is specific to CT neurons with distinct thalamic connectivity. Using mice (either sex) combined with in vitro electrophysiology techniques, optogenetics, and retrograde labeling, we describe studies of vibrissal primary motor cortex (vM1) influences on different CT neurons in the vibrissal primary somatosensory cortex (vS1) with distinct intrathalamic axonal projections. We found that vM1 inputs are highly selective, evoking stronger postsynaptic responses in CT neurons projecting to the dual ventral posterior medial nucleus (VPm) and posterior medial nucleus (POm) located in lower L6a than VPm-only-projecting CT cells in upper L6a. A targeted analysis of the specific cells and synapses involved revealed that the greater responsiveness of Dual CT neurons was due to their distinctive intrinsic membrane properties and synaptic mechanisms. These data demonstrate that vS1 has at least two discrete L6 CT subcircuits distinguished by their thalamic projection patterns, intrinsic physiology, and functional connectivity with vM1. Our results also provide insights into how a distinct CT subcircuit may serve specialized roles specific to contextual modulation of tactile-related sensory signals in the somatosensory thalamus during active vibrissa movements.
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Affiliation(s)
- Luis E Martinetti
- Neuroscience Program, Michigan State University, East Lansing, Michigan 48824
| | - Dawn M Autio
- Department of Physiology, Michigan State University, East Lansing, Michigan 48824
| | - Shane R Crandall
- Neuroscience Program, Michigan State University, East Lansing, Michigan 48824
- Department of Physiology, Michigan State University, East Lansing, Michigan 48824
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3
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Martinetti LE, Autio DM, Crandall SR. Motor Control of Distinct Layer 6 Corticothalamic Feedback Circuits. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590613. [PMID: 38712153 PMCID: PMC11071411 DOI: 10.1101/2024.04.22.590613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Layer 6 corticothalamic (L6 CT) neurons provide massive input to the thalamus, and these feedback connections enable the cortex to influence its own sensory input by modulating thalamic excitability. However, the functional role(s) feedback serves during sensory processing is unclear. One hypothesis is that CT feedback is under the control of extra-sensory signals originating from higher-order cortical areas, yet we know nothing about the mechanisms of such control. It is also unclear whether such regulation is specific to CT neurons with distinct thalamic connectivity. Using mice (either sex) combined with in vitro electrophysiology techniques, optogenetics, and retrograde labeling, we describe studies of vibrissal primary motor cortex (vM1) influences on different CT neurons in the vibrissal primary somatosensory cortex (vS1) with distinct intrathalamic axonal projections. We found that vM1 inputs are highly selective, evoking stronger postsynaptic responses in Dual ventral posterior medial nucleus (VPm) and posterior medial nucleus (POm) projecting CT neurons located in lower L6a than VPm-only projecting CT cells in upper L6a. A targeted analysis of the specific cells and synapses involved revealed that the greater responsiveness of Dual CT neurons was due to their distinctive intrinsic membrane properties and synaptic mechanisms. These data demonstrate that vS1 has at least two discrete L6 CT subcircuits distinguished by their thalamic projection patterns, intrinsic physiology, and functional connectivity with vM1. Our results also provide insights into how a distinct CT subcircuit may serve specialized roles specific to contextual modulation of tactile-related sensory signals in the somatosensory thalamus during active vibrissa movements.
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Affiliation(s)
| | - Dawn M. Autio
- Department of Physiology, Michigan State University, East Lansing, MI 48824
| | - Shane R. Crandall
- Neuroscience Program, Michigan State University, East Lansing, MI 48824
- Department of Physiology, Michigan State University, East Lansing, MI 48824
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4
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Zolnik TA, Bronec A, Ross A, Staab M, Sachdev RNS, Molnár Z, Eickholt BJ, Larkum ME. Layer 6b controls brain state via apical dendrites and the higher-order thalamocortical system. Neuron 2024; 112:805-820.e4. [PMID: 38101395 DOI: 10.1016/j.neuron.2023.11.021] [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: 03/10/2023] [Revised: 09/11/2023] [Accepted: 11/18/2023] [Indexed: 12/17/2023]
Abstract
The deepest layer of the cortex (layer 6b [L6b]) contains relatively few neurons, but it is the only cortical layer responsive to the potent wake-promoting neuropeptide orexin/hypocretin. Can these few neurons significantly influence brain state? Here, we show that L6b-photoactivation causes a surprisingly robust enhancement of attention-associated high-gamma oscillations and population spiking while abolishing slow waves in sleep-deprived mice. To explain this powerful impact on brain state, we investigated L6b's synaptic output using optogenetics, electrophysiology, and monoCaTChR ex vivo. We found powerful output in the higher-order thalamus and apical dendrites of L5 pyramidal neurons, via L1a and L5a, as well as in superior colliculus and L6 interneurons. L6b subpopulations with distinct morphologies and short- and long-term plasticities project to these diverse targets. The L1a-targeting subpopulation triggered powerful NMDA-receptor-dependent spikes that elicited burst firing in L5. We conclude that orexin/hypocretin-activated cortical neurons form a multifaceted, fine-tuned circuit for the sustained control of the higher-order thalamocortical system.
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Affiliation(s)
- Timothy Adam Zolnik
- Department of Biochemistry, Charité Universitätsmedizin Berlin, Berlin 10117, Germany; Department of Biology, Humboldt Universität zu Berlin, Berlin 10117, Germany.
| | - Anna Bronec
- Department of Biology, Humboldt Universität zu Berlin, Berlin 10117, Germany
| | - Annemarie Ross
- Department of Biology, Humboldt Universität zu Berlin, Berlin 10117, Germany
| | - Marcel Staab
- Department of Biology, Humboldt Universität zu Berlin, Berlin 10117, Germany
| | - Robert N S Sachdev
- Department of Biology, Humboldt Universität zu Berlin, Berlin 10117, Germany
| | - Zoltán Molnár
- Department of Biochemistry, Charité Universitätsmedizin Berlin, Berlin 10117, Germany; Department of Physiology, Anatomy, and Genetics, University of Oxford, Parks Road, Sherrington Building, Oxford OX1 3PT, UK
| | | | - Matthew Evan Larkum
- Department of Biology, Humboldt Universität zu Berlin, Berlin 10117, Germany.
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5
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Hönigsperger C, Storm JF, Arena A. Laminar evoked responses in mouse somatosensory cortex suggest a special role for deep layers in cortical complexity. Eur J Neurosci 2024; 59:752-770. [PMID: 37586411 DOI: 10.1111/ejn.16108] [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: 12/13/2022] [Revised: 07/03/2023] [Accepted: 07/20/2023] [Indexed: 08/18/2023]
Abstract
It has been suggested that consciousness is closely related to the complexity of the brain. The perturbational complexity index (PCI) has been used in humans and rodents to distinguish conscious from unconscious states based on the global cortical responses (recorded by electroencephalography, EEG) to local cortical stimulation (CS). However, it is unclear how different cortical layers respond to CS and contribute to the resulting intra- and inter-areal cortical connectivity and PCI. A detailed investigation of the local dynamics is needed to understand the basis for PCI. We hypothesized that the complexity level of global cortical responses (PCI) correlates with layer-specific activity and connectivity. We tested this idea by measuring global cortical dynamics and layer-specific activity in the somatosensory cortex (S1) of mice, combining cortical electrical stimulation in deep motor cortex, global electrocorticography (ECoG) and local laminar recordings from layers 1-6 in S1, during wakefulness and general anaesthesia (sevoflurane). We found that the transition from wake to sevoflurane anaesthesia correlated with a drop in both the global and local PCI (PCIst ) values (complexity). This was accompanied by a local decrease in neural firing rate, spike-field coherence and long-range functional connectivity specific to deep layers (L5, L6). Our results suggest that deep cortical layers are mechanistically important for changes in PCI and thereby for changes in the state of consciousness.
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Affiliation(s)
| | - Johan F Storm
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Alessandro Arena
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
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6
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Bergmann J, Petro LS, Abbatecola C, Li MS, Morgan AT, Muckli L. Cortical depth profiles in primary visual cortex for illusory and imaginary experiences. Nat Commun 2024; 15:1002. [PMID: 38307834 PMCID: PMC10837448 DOI: 10.1038/s41467-024-45065-w] [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: 12/19/2022] [Accepted: 01/12/2024] [Indexed: 02/04/2024] Open
Abstract
Visual illusions and mental imagery are non-physical sensory experiences that involve cortical feedback processing in the primary visual cortex. Using laminar functional magnetic resonance imaging (fMRI) in two studies, we investigate if information about these internal experiences is visible in the activation patterns of different layers of primary visual cortex (V1). We find that imagery content is decodable mainly from deep layers of V1, whereas seemingly 'real' illusory content is decodable mainly from superficial layers. Furthermore, illusory content shares information with perceptual content, whilst imagery content does not generalise to illusory or perceptual information. Together, our results suggest that illusions and imagery, which differ immensely in their subjective experiences, also involve partially distinct early visual microcircuits. However, overlapping microcircuit recruitment might emerge based on the nuanced nature of subjective conscious experience.
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Affiliation(s)
- Johanna Bergmann
- Imaging Centre of Excellence (ICE), Queen Elizabeth University Hospital, University of Glasgow, Glasgow, UK.
- Centre for Cognitive Neuroimaging (CCNi), School of Psychology and Neuroscience, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
- Department of Psychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Lucy S Petro
- Imaging Centre of Excellence (ICE), Queen Elizabeth University Hospital, University of Glasgow, Glasgow, UK
- Centre for Cognitive Neuroimaging (CCNi), School of Psychology and Neuroscience, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Clement Abbatecola
- Imaging Centre of Excellence (ICE), Queen Elizabeth University Hospital, University of Glasgow, Glasgow, UK
- Centre for Cognitive Neuroimaging (CCNi), School of Psychology and Neuroscience, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Min S Li
- Centre for Cognitive Neuroimaging (CCNi), School of Psychology and Neuroscience, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- Centre for Computational Neuroscience and Cognitive Robotics, School of Psychology, University of Birmingham, Birmingham, UK
| | - A Tyler Morgan
- Imaging Centre of Excellence (ICE), Queen Elizabeth University Hospital, University of Glasgow, Glasgow, UK
- Centre for Cognitive Neuroimaging (CCNi), School of Psychology and Neuroscience, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- Functional MRI Core Facility, National Institute of Mental Health, NIH, Bethesda, MD, 20817, USA
| | - Lars Muckli
- Imaging Centre of Excellence (ICE), Queen Elizabeth University Hospital, University of Glasgow, Glasgow, UK.
- Centre for Cognitive Neuroimaging (CCNi), School of Psychology and Neuroscience, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
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7
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Huang S, Wu SJ, Sansone G, Ibrahim LA, Fishell G. Layer 1 neocortex: Gating and integrating multidimensional signals. Neuron 2024; 112:184-200. [PMID: 37913772 PMCID: PMC11180419 DOI: 10.1016/j.neuron.2023.09.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/23/2023] [Accepted: 09/28/2023] [Indexed: 11/03/2023]
Abstract
Layer 1 (L1) of the neocortex acts as a nexus for the collection and processing of widespread information. By integrating ascending inputs with extensive top-down activity, this layer likely provides critical information regulating how the perception of sensory inputs is reconciled with expectation. This is accomplished by sorting, directing, and integrating the complex network of excitatory inputs that converge onto L1. These signals are combined with neuromodulatory afferents and gated by the wealth of inhibitory interneurons that either are embedded within L1 or send axons from other cortical layers. Together, these interactions dynamically calibrate information flow throughout the neocortex. This review will primarily focus on L1 within the primary sensory cortex and will use these insights to understand L1 in other cortical areas.
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Affiliation(s)
- Shuhan Huang
- Harvard Medical School, Blavatnik Institute, Department of Neurobiology, Boston, MA 02115, USA; Program in Neuroscience, Harvard University, Cambridge, MA 02138, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Sherry Jingjing Wu
- Harvard Medical School, Blavatnik Institute, Department of Neurobiology, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Giulia Sansone
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Leena Ali Ibrahim
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Gord Fishell
- Harvard Medical School, Blavatnik Institute, Department of Neurobiology, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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8
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Ledderose JMT, Zolnik TA, Toumazou M, Trimbuch T, Rosenmund C, Eickholt BJ, Jaeger D, Larkum ME, Sachdev RNS. Layer 1 of somatosensory cortex: an important site for input to a tiny cortical compartment. Cereb Cortex 2023; 33:11354-11372. [PMID: 37851709 PMCID: PMC10690867 DOI: 10.1093/cercor/bhad371] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 09/17/2023] [Indexed: 10/20/2023] Open
Abstract
Neocortical layer 1 has been proposed to be at the center for top-down and bottom-up integration. It is a locus for interactions between long-range inputs, layer 1 interneurons, and apical tuft dendrites of pyramidal neurons. While input to layer 1 has been studied intensively, the level and effect of input to this layer has still not been completely characterized. Here we examined the input to layer 1 of mouse somatosensory cortex with retrograde tracing and optogenetics. Our assays reveal that local input to layer 1 is predominantly from layers 2/3 and 5 pyramidal neurons and interneurons, and that subtypes of local layers 5 and 6b neurons project to layer 1 with different probabilities. Long-range input from sensory-motor cortices to layer 1 of somatosensory cortex arose predominantly from layers 2/3 neurons. Our optogenetic experiments showed that intra-telencephalic layer 5 pyramidal neurons drive layer 1 interneurons but have no effect locally on layer 5 apical tuft dendrites. Dual retrograde tracing revealed that a fraction of local and long-range neurons was both presynaptic to layer 5 neurons and projected to layer 1. Our work highlights the prominent role of local inputs to layer 1 and shows the potential for complex interactions between long-range and local inputs, which are both in position to modify the output of somatosensory cortex.
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Affiliation(s)
- Julia M T Ledderose
- Institute of Biology, Humboldt Universität zu Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
- Institute of Molecular Biology and Biochemistry, Charité—Universitätsmedizin Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
| | - Timothy A Zolnik
- Institute of Biology, Humboldt Universität zu Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
- Institute of Molecular Biology and Biochemistry, Charité—Universitätsmedizin Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
| | - Maria Toumazou
- Institute of Biology, Humboldt Universität zu Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
| | - Thorsten Trimbuch
- Institute of Neurophysiology, Charité—Universitätsmedizin Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
| | - Christian Rosenmund
- Institute of Neurophysiology, Charité—Universitätsmedizin Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
- Neurocure Centre for Excellence Charité—Universitätsmedizin Berlin Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
| | | | - Dieter Jaeger
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Matthew E Larkum
- Institute of Biology, Humboldt Universität zu Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
- Neurocure Centre for Excellence Charité—Universitätsmedizin Berlin Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
| | - Robert N S Sachdev
- Institute of Biology, Humboldt Universität zu Berlin, Charitéplatz 1, Virchowweg 6, 10117 Berlin, Germany
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9
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Munn BR, Müller EJ, Aru J, Whyte CJ, Gidon A, Larkum ME, Shine JM. A thalamocortical substrate for integrated information via critical synchronous bursting. Proc Natl Acad Sci U S A 2023; 120:e2308670120. [PMID: 37939085 PMCID: PMC10655573 DOI: 10.1073/pnas.2308670120] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 09/21/2023] [Indexed: 11/10/2023] Open
Abstract
Understanding the neurobiological mechanisms underlying consciousness remains a significant challenge. Recent evidence suggests that the coupling between distal-apical and basal-somatic dendrites in thick-tufted layer 5 pyramidal neurons (L5PN), regulated by the nonspecific-projecting thalamus, is crucial for consciousness. Yet, it is uncertain whether this thalamocortical mechanism can support emergent signatures of consciousness, such as integrated information. To address this question, we constructed a biophysical network of dual-compartment thick-tufted L5PN, with dendrosomatic coupling controlled by thalamic inputs. Our findings demonstrate that integrated information is maximized when nonspecific thalamic inputs drive the system into a regime of time-varying synchronous bursting. Here, the system exhibits variable spiking dynamics with broad pairwise correlations, supporting the enhanced integrated information. Further, the observed peak in integrated information aligns with criticality signatures and empirically observed layer 5 pyramidal bursting rates. These results suggest that the thalamocortical core of the mammalian brain may be evolutionarily configured to optimize effective information processing, providing a potential neuronal mechanism that integrates microscale theories with macroscale signatures of consciousness.
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Affiliation(s)
- Brandon R. Munn
- Brain and Mind Centre, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney2050, Australia
- Complex Systems, School of Physics, Faculty of Science, University of Sydney, Sydney2050, Australia
| | - Eli J. Müller
- Brain and Mind Centre, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney2050, Australia
- Complex Systems, School of Physics, Faculty of Science, University of Sydney, Sydney2050, Australia
| | - Jaan Aru
- Institute of Computer Science, University of Tartu, Tartu51009, Estonia
| | - Christopher J. Whyte
- Brain and Mind Centre, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney2050, Australia
- Complex Systems, School of Physics, Faculty of Science, University of Sydney, Sydney2050, Australia
| | - Albert Gidon
- Institute of Biology, Humboldt University of Berlin, Berlin10099, Germany
- NeuroCure Center of Excellence, Charité Universitätsmedizin Berlin, Berlin10099, Germany
| | - Matthew E. Larkum
- Institute of Biology, Humboldt University of Berlin, Berlin10099, Germany
- NeuroCure Center of Excellence, Charité Universitätsmedizin Berlin, Berlin10099, Germany
| | - James M. Shine
- Brain and Mind Centre, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney2050, Australia
- Complex Systems, School of Physics, Faculty of Science, University of Sydney, Sydney2050, Australia
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10
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Feldmeyer D. Structure and function of neocortical layer 6b. Front Cell Neurosci 2023; 17:1257803. [PMID: 37744882 PMCID: PMC10516558 DOI: 10.3389/fncel.2023.1257803] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/14/2023] [Indexed: 09/26/2023] Open
Abstract
Cortical layer 6b is considered by many to be a remnant of the subplate that forms during early stages of neocortical development, but its role in the adult is not well understood. Its neuronal complement has only recently become the subject of systematic studies, and its axonal projections and synaptic input structures have remained largely unexplored despite decades of research into neocortical function. In recent years, however, layer 6b (L6b) has attracted increasing attention and its functional role is beginning to be elucidated. In this review, I will attempt to provide an overview of what is currently known about the excitatory and inhibitory neurons in this layer, their pre- and postsynaptic connectivity, and their functional implications. Similarities and differences between different cortical areas will be highlighted. Finally, layer 6b neurons are highly responsive to several neuropeptides such as orexin/hypocretin, neurotensin and cholecystokinin, in some cases exclusively. They are also strongly controlled by neurotransmitters such as acetylcholine and norepinephrine. The interaction of these neuromodulators with L6b microcircuitry and its functional consequences will also be discussed.
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Affiliation(s)
- Dirk Feldmeyer
- Research Centre Jülich, Institute of Neuroscience and Medicine 10 (INM-10), Jülich, Germany
- Department of Psychiatry, Psychotherapy, and Psychosomatics, RWTH Aachen University Hospital, Aachen, Germany
- Jülich-Aachen Research Alliance, Translational Brain Medicine (JARA Brain), Aachen, Germany
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11
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Bender PTR, McCollum M, Boyd-Pratt H, Mendelson BZ, Anderson CT. Synaptic zinc potentiates AMPA receptor function in mouse auditory cortex. Cell Rep 2023; 42:112932. [PMID: 37585291 PMCID: PMC10514716 DOI: 10.1016/j.celrep.2023.112932] [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: 04/05/2023] [Revised: 06/23/2023] [Accepted: 07/18/2023] [Indexed: 08/18/2023] Open
Abstract
Synaptic zinc signaling modulates synaptic activity and is present in specific populations of cortical neurons, suggesting that synaptic zinc contributes to the diversity of intracortical synaptic microcircuits and their functional specificity. To understand the role of zinc signaling in the cortex, we performed whole-cell patch-clamp recordings from intratelencephalic (IT)-type neurons and pyramidal tract (PT)-type neurons in layer 5 of the mouse auditory cortex during optogenetic stimulation of specific classes of presynaptic neurons. Our results show that synaptic zinc potentiates AMPA receptor (AMPAR) function in a synapse-specific manner. We performed in vivo 2-photon calcium imaging of the same classes of neurons in awake mice and found that changes in synaptic zinc can widen or sharpen the sound-frequency tuning bandwidth of IT-type neurons but only widen the tuning bandwidth of PT-type neurons. These results provide evidence for synapse- and cell-type-specific actions of synaptic zinc in the cortex.
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Affiliation(s)
- Philip T R Bender
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Mason McCollum
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Helen Boyd-Pratt
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Benjamin Z Mendelson
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Charles T Anderson
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV 26506, USA.
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12
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Galazo MJ, Sweetser DA, Macklis JD. Tle4 controls both developmental acquisition and early post-natal maturation of corticothalamic projection neuron identity. Cell Rep 2023; 42:112957. [PMID: 37561632 PMCID: PMC10542749 DOI: 10.1016/j.celrep.2023.112957] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 04/21/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023] Open
Abstract
Identities of distinct neuron subtypes are specified during embryonic development, then maintained during post-natal maturation. In cerebral cortex, mechanisms controlling early acquisition of neuron-subtype identities have become increasingly understood. However, mechanisms controlling neuron-subtype identity stability during post-natal maturation are largely unexplored. We identify that Tle4 is required for both early acquisition and post-natal stability of corticothalamic neuron-subtype identity. Embryonically, Tle4 promotes acquisition of corticothalamic identity and blocks emergence of core characteristics of subcerebral/corticospinal projection neuron identity, including gene expression and connectivity. During the first post-natal week, when corticothalamic innervation is ongoing, Tle4 is required to stabilize corticothalamic neuron identity, limiting interference from differentiation programs of developmentally related neuron classes. We identify a deacetylation-based epigenetic mechanism by which TLE4 controls Fezf2 expression level by corticothalamic neurons. This contributes to distinction of cortical output subtypes and ensures identity stability for appropriate maturation of corticothalamic neurons.
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Affiliation(s)
- Maria J Galazo
- Department of Stem Cell and Regenerative Biology, and Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - David A Sweetser
- Department of Pediatrics, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Jeffrey D Macklis
- Department of Stem Cell and Regenerative Biology, and Center for Brain Science, Harvard University, Cambridge, MA 02138, USA.
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13
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Tian D, Izumi SI. Different effects of I-wave periodicity repetitive TMS on motor cortex interhemispheric interaction. Front Neurosci 2023; 17:1079432. [PMID: 37457007 PMCID: PMC10349661 DOI: 10.3389/fnins.2023.1079432] [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: 10/26/2022] [Accepted: 06/12/2023] [Indexed: 07/18/2023] Open
Abstract
Background Activity of the neural circuits in the human motor cortex can be probed using transcranial magnetic stimulation (TMS). Changing TMS-induced current direction recruits different cortical neural circuits. I-wave periodicity repetitive TMS (iTMS) substantially modulates motor cortex excitability through neural plasticity, yet its effect on interhemispheric interaction remains unclear. Objective To explore the modulation of interhemispheric interaction by iTMS applied in different current directions. Materials and Methods Twenty right-handed healthy young volunteers (aged 27.5 ± 5.0 years) participated in this study with three visits. On each visit, iTMS in posterior-anterior/anterior-posterior direction (PA-/AP-iTMS) or sham-iTMS was applied to the right hemisphere, with corticospinal excitability and intracortical facilitation of the non-stimulated left hemisphere evaluated at four timepoints. Ipsilateral silent period was also measured at each timepoint probing interhemispheric inhibition (IHI). Results PA- and AP-iTMS potentiated cortical excitability concurrently in the stimulated right hemisphere. Corticospinal excitability of the non-stimulated left hemisphere increased 10 min after both PA- and AP-iTMS intervention, with a decrease in short-interval intracortical facilitation (SICF) observed in AP-iTMS only. Immediately after the intervention, PA-iTMS tilted the IHI balance toward inhibiting the non-stimulated hemisphere, while AP-iTMS shifted the balance toward the opposite direction. Conclusions Our findings provide systematic evidence on the plastic modulation of interhemispheric interaction by PA- and AP-iTMS. We show that iTMS induces an interhemispheric facilitatory effect, and that PA- and AP-iTMS differs in modulating interhemispheric inhibition.
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Affiliation(s)
- Dongting Tian
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Shin-Ichi Izumi
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduate School of Medicine, Sendai, Japan
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
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14
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Bennett HC, Zhang Q, Wu YT, Chon U, Pi HJ, Drew PJ, Kim Y. Aging drives cerebrovascular network remodeling and functional changes in the mouse brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.23.541998. [PMID: 37305850 PMCID: PMC10257218 DOI: 10.1101/2023.05.23.541998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Aging is the largest risk factor for neurodegenerative disorders, and commonly associated with compromised cerebrovasculature and pericytes. However, we do not know how normal aging differentially impacts the vascular structure and function in different brain areas. Here we utilize mesoscale microscopy methods (serial two-photon tomography and light sheet microscopy) and in vivo imaging (wide field optical spectroscopy and two-photon imaging) to determine detailed changes in aged cerebrovascular networks. Whole-brain vascular tracing showed an overall ~10% decrease in vascular length and branching density, and light sheet imaging with 3D immunolabeling revealed increased arteriole tortuosity in aged brains. Vasculature and pericyte densities showed significant reductions in the deep cortical layers, hippocampal network, and basal forebrain areas. Moreover, in vivo imaging in awake mice identified delays in neurovascular coupling and disrupted blood oxygenation. Collectively, we uncover regional vulnerabilities of cerebrovascular network and physiological changes that can mediate cognitive decline in normal aging.
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Affiliation(s)
- Hannah C Bennett
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
- Equal contribution
| | - Qingguang Zhang
- Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
- Equal contribution
| | - Yuan-Ting Wu
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Uree Chon
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Hyun-Jae Pi
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Patrick J Drew
- Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
- Biomedical Engineering, Biology, and Neurosurgery, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Yongsoo Kim
- Department of Neural and Behavioral Sciences, The Pennsylvania State University, Hershey, PA, 17033, USA
- Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
- Lead contact
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15
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Brunelle DL, Llano DA. Role of auditory-somatosensory corticothalamic circuit integration in analgesia. Cell Calcium 2023; 111:102717. [PMID: 36931195 PMCID: PMC10755628 DOI: 10.1016/j.ceca.2023.102717] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/14/2023]
Abstract
Our sensory environment is permeated by a diverse array of auditory and somatosensory stimuli. The pairing of acoustic signals with concurrent or forthcoming tactile cues are abundant in everyday life and various survival contexts across species, thus deeming the ability to integrate sensory inputs arising from the combination of these stimuli as crucial. The corticothalamic system plays a critical role in orchestrating the construction, integration and distribution of the information extracted from these sensory modalities. In this mini-review, we provide a circuit-level description of the auditory corticothalamic pathway in conjunction with adjacent corticothalamic somatosensory projections. Although the extent of the functional interactions shared by these pathways is not entirely elucidated, activation of each of these systems appears to modulate sensory perception in the complementary domain. Several specific issues are reviewed. Under certain environmental noise conditions, the spectral information of a sound could induce modulations in nociception and even induce analgesia. We begin by discussing recent findings by Zhou et al. (2022) implicating the corticothalamic system in mediating sound-induced analgesia. Next, we describe relevant components of the corticothalamic pathway's functional organization. Additionally, we describe an emerging body of literature pointing to intrathalamic circuitry being optimal for controlling and selecting sensory signals across modalities, with the thalamic reticular nucleus being a candidate mechanism for directing cross-modal interactions. Finally, Ca2+ bursting in thalamic neurons evoked by the thalamic reticular nucleus is explored.
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Affiliation(s)
- Dimitri L Brunelle
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Daniel A Llano
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America.
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16
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Zamfir M, Sharif B, Locke S, Ehrlich AT, Ochandarena NE, Scherrer G, Ribeiro-da-Silva A, Kieffer BL, Séguéla P. Distinct and sex-specific expression of mu opioid receptors in anterior cingulate and somatosensory S1 cortical areas. Pain 2023; 164:703-716. [PMID: 35973045 PMCID: PMC10026835 DOI: 10.1097/j.pain.0000000000002751] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/24/2022] [Accepted: 07/22/2022] [Indexed: 11/25/2022]
Abstract
ABSTRACT The anterior cingulate cortex (ACC) processes the affective component of pain, whereas the primary somatosensory cortex (S1) is involved in its sensory-discriminative component. Injection of morphine in the ACC has been reported to be analgesic, and endogenous opioids in this area are required for pain relief. Mu opioid receptors (MORs) are expressed in both ACC and S1; however, the identity of MOR-expressing cortical neurons remains unknown. Using the Oprm1-mCherry mouse line, we performed selective patch clamp recordings of MOR+ neurons, as well as immunohistochemistry with validated neuronal markers, to determine the identity and laminar distribution of MOR+ neurons in ACC and S1. We found that the electrophysiological signatures of MOR+ neurons differ significantly between these 2 areas, with interneuron-like firing patterns more frequent in ACC. While MOR+ somatostatin interneurons are more prominent in ACC, MOR+ excitatory neurons and MOR+ parvalbumin interneurons are more prominent in S1. Our results suggest a differential contribution of MOR-mediated modulation to ACC and S1 outputs. We also found that females had a greater density of MOR+ neurons compared with males in both areas. In summary, we conclude that MOR-dependent opioidergic signaling in the cortex displays sexual dimorphisms and likely evolved to meet the distinct function of pain-processing circuits in limbic and sensory cortical areas.
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Affiliation(s)
- Maria Zamfir
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Behrang Sharif
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - Samantha Locke
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Aliza T. Ehrlich
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Douglas Hospital Research Institute, McGill University, Montreal, QC, Canada
| | - Nicole E. Ochandarena
- Department of Cell Biology and Physiology The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Grégory Scherrer
- Department of Cell Biology and Physiology The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- UNC Neuroscience Center The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Alfredo Ribeiro-da-Silva
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Brigitte L. Kieffer
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Douglas Hospital Research Institute, McGill University, Montreal, QC, Canada
| | - Philippe Séguéla
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
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17
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Luhmann HJ. Malformations-related neocortical circuits in focal seizures. Neurobiol Dis 2023; 178:106018. [PMID: 36706927 DOI: 10.1016/j.nbd.2023.106018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/18/2023] [Accepted: 01/23/2023] [Indexed: 01/25/2023] Open
Abstract
This review article gives an overview on the molecular, cellular and network mechanisms underlying focal seizures in neocortical networks with developmental malformations. Neocortical malformations comprise a large variety of structural abnormalities associated with epilepsy and other neurological and psychiatric disorders. Genetic or acquired disorders of neocortical cell proliferation, neuronal migration and/or programmed cell death may cause pathologies ranging from the expression of dysmorphic neurons and heterotopic cell clusters to abnormal layering and cortical misfolding. After providing a brief overview on the pathogenesis and structure of neocortical malformations in humans, animal models are discussed and how they contributed to our understanding on the mechanisms of neocortical hyperexcitability associated with developmental disorders. State-of-the-art molecular biological and electrophysiological techniques have been also used in humans and on resectioned neocortical tissue of epileptic patients and provide deep insights into the subcellular, cellular and network mechanisms contributing to focal seizures. Finally, a brief outlook is given how novel models and methods can shape translational research in the near future.
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Affiliation(s)
- Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, Mainz, Germany.
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18
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Venkatesan S, Chen T, Liu Y, Turner EE, Tripathy SJ, Lambe EK. Chrna5 and lynx prototoxins identify acetylcholine super-responder subplate neurons. iScience 2023; 26:105992. [PMID: 36798433 PMCID: PMC9926215 DOI: 10.1016/j.isci.2023.105992] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 11/22/2022] [Accepted: 01/12/2023] [Indexed: 01/15/2023] Open
Abstract
Attention depends on cholinergic excitation of prefrontal neurons but is sensitive to perturbation of α5-containing nicotinic receptors encoded by Chrna5. However, Chrna5-expressing (Chrna5+) neurons remain enigmatic, despite their potential as a target to improve attention. Here, we generate complex transgenic mice to probe Chrna5+ neurons and their sensitivity to endogenous acetylcholine. Through opto-physiological experiments, we discover that Chrna5+ neurons contain a distinct population of acetylcholine super-responders. Leveraging single-cell transcriptomics, we discover molecular markers conferring subplate identity on this subset. We determine that Chrna5+ super-responders express a unique complement of GPI-anchored lynx prototoxin genes (Lypd1, Ly6g6e, and Lypd6b), predicting distinct nicotinic receptor regulation. To manipulate lynx regulation of endogenous nicotinic responses, we developed a pharmacological strategy guided by transcriptomic predictions. Overall, we reveal Chrna5-Cre mice as a transgenic tool to target the diversity of subplate neurons in adulthood, yielding new molecular strategies to manipulate their cholinergic activation relevant to attention disorders.
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Affiliation(s)
- Sridevi Venkatesan
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada
| | - Tianhui Chen
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada
| | - Yupeng Liu
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada
| | - Eric E. Turner
- Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Shreejoy J. Tripathy
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada,Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Evelyn K. Lambe
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Department of Obstetrics and Gynecology, University of Toronto, Toronto, ON, Canada,Corresponding author
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19
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Shine JM. Adaptively navigating affordance landscapes: How interactions between the superior colliculus and thalamus coordinate complex, adaptive behaviour. Neurosci Biobehav Rev 2022; 143:104921. [DOI: 10.1016/j.neubiorev.2022.104921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 09/08/2022] [Accepted: 09/08/2022] [Indexed: 11/06/2022]
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20
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van Hoogstraten WS, Lute MCC, Nusselder H, Kros L, van den Maagdenberg AMJM, De Zeeuw CI. cATR Tracing Approach to Identify Individual Intermediary Neurons Based on Their Input and Output: A Proof-of-Concept Study Connecting Cerebellum and Central Hubs Implicated in Developmental Disorders. Cells 2022; 11:cells11192978. [PMID: 36230940 PMCID: PMC9562212 DOI: 10.3390/cells11192978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/25/2022] Open
Abstract
Over the past decades, it has become increasingly clear that many neurodevelopmental disorders can be characterized by aberrations in the neuro-anatomical connectome of intermediary hubs. Yet, despite the advent in unidirectional transsynaptic tracing technologies, we are still lacking an efficient approach to identify individual neurons based on both their precise input and output relations, hampering our ability to elucidate the precise connectome in both the healthy and diseased condition. Here, we bridge this gap by combining anterograde transsynaptic- and retrograde (cATR) tracing in Ai14 reporter mice, using adeno-associated virus serotype 1 expressing Cre and cholera toxin subunit B as the anterograde and retrograde tracer, respectively. We have applied this innovative approach to selectively identify individual neurons in the brainstem that do not only receive input from one or more of the cerebellar nuclei (CN), but also project to the primary motor cortex (M1), the amygdala or the ventral tegmental area (VTA). Cells directly connecting CN to M1 were found mainly in the thalamus, while a large diversity of midbrain and brainstem areas connected the CN to the amygdala or VTA. Our data highlight that cATR allows for specific, yet brain-wide, identification of individual neurons that mediate information from a cerebellar nucleus to the cerebral cortex, amygdala or VTA via a disynaptic pathway. Given that the identified neurons in healthy subjects can be readily quantified, our data also form a solid foundation to make numerical comparisons with mouse mutants suffering from aberrations in their connectome due to a neurodevelopmental disorder.
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Affiliation(s)
| | - Marit C. C. Lute
- Department of Neuroscience, Erasmus Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Hugo Nusselder
- Department of Neuroscience, Erasmus Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Lieke Kros
- Department of Neuroscience, Erasmus Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Arn M. J. M. van den Maagdenberg
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Neurology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Chris I. De Zeeuw
- Department of Neuroscience, Erasmus Medical Center, 3015 CN Rotterdam, The Netherlands
- Netherlands Institute for Neuroscience, NIN-KNAW, 1105 BA Amsterdam, The Netherlands
- Correspondence:
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21
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Ben-Simon Y, Kaefer K, Velicky P, Csicsvari J, Danzl JG, Jonas P. A direct excitatory projection from entorhinal layer 6b neurons to the hippocampus contributes to spatial coding and memory. Nat Commun 2022; 13:4826. [PMID: 35974109 PMCID: PMC9381769 DOI: 10.1038/s41467-022-32559-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/03/2022] [Indexed: 11/08/2022] Open
Abstract
The mammalian hippocampal formation (HF) plays a key role in several higher brain functions, such as spatial coding, learning and memory. Its simple circuit architecture is often viewed as a trisynaptic loop, processing input originating from the superficial layers of the entorhinal cortex (EC) and sending it back to its deeper layers. Here, we show that excitatory neurons in layer 6b of the mouse EC project to all sub-regions comprising the HF and receive input from the CA1, thalamus and claustrum. Furthermore, their output is characterized by unique slow-decaying excitatory postsynaptic currents capable of driving plateau-like potentials in their postsynaptic targets. Optogenetic inhibition of the EC-6b pathway affects spatial coding in CA1 pyramidal neurons, while cell ablation impairs not only acquisition of new spatial memories, but also degradation of previously acquired ones. Our results provide evidence of a functional role for cortical layer 6b neurons in the adult brain.
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Affiliation(s)
- Yoav Ben-Simon
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria.
- Department of Neurophysiology and Pharmacology, Vienna Medical University, Vienna, Austria.
| | - Karola Kaefer
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
- Department of Neuroinformatics, Radboud University, Nijmegen, The Netherlands
| | - Philipp Velicky
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Jozsef Csicsvari
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Johann G Danzl
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Peter Jonas
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
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22
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Ledderose JMT, Benitez JA, Roberts AJ, Reed R, Bintig W, Larkum ME, Sachdev RNS, Furnari F, Eickholt BJ. The impact of phosphorylated PTEN at threonine 366 on cortical connectivity and behaviour. Brain 2022; 145:3608-3621. [PMID: 35603900 DOI: 10.1093/brain/awac188] [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: 09/29/2021] [Revised: 04/19/2022] [Accepted: 05/04/2022] [Indexed: 11/14/2022] Open
Abstract
The lipid phosphatase PTEN (phosphatase and tensin homologue on chromosome 10) is a key tumour suppressor gene and an important regulator of neuronal signalling. PTEN mutations have been identified in patients with autism spectrum disorders, characterized by macrocephaly, impaired social interactions and communication, repetitive behaviour, intellectual disability, and epilepsy. PTEN enzymatic activity is regulated by a cluster of phosphorylation sites at the C-terminus of the protein. Here, we focussed on the role of PTEN T366 phosphorylation and generated a knock-in mouse line in which Pten T366 was substituted with alanine (PtenT366A/T366A). We identify that phosphorylation of PTEN at T366 controls neuron size and connectivity of brain circuits involved in sensory processing. We show in behavioural tests that PtenT366/T366A mice exhibit cognitive deficits and selective sensory impairments, with significant differences in male individuals. We identify restricted cellular overgrowth of cortical neurons in PtenT366A/T366A brains, linked to increases in both dendritic arborization and soma size. In a combinatorial approach of anterograde and retrograde monosynaptic tracing using rabies virus, we characterize differences in connectivity to the primary somatosensory cortex of PtenT366A/T366A brains, with imbalances in long-range cortico-cortical input to neurons. We conclude that phosphorylation of PTEN at T366 controls neuron size and connectivity of brain circuits involved in sensory processing and propose that PTEN T366 signalling may account for a subset of autism-related functions of PTEN.
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Affiliation(s)
- Julia M T Ledderose
- Institute for Biochemistry, Charité Universitätsmedizin Berlin, Germany.,Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jorge A Benitez
- Bristol Myers Squibb, 10300 Campus Point Drive, Suite 100, San Diego, California, 92121, USA
| | - Amanda J Roberts
- The Scripps Research Institute, Animal Models Core, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Rachel Reed
- Bristol Myers Squibb, 10300 Campus Point Drive, Suite 100, San Diego, California, 92121, USA
| | - Willem Bintig
- Institute for Biochemistry, Charité Universitätsmedizin Berlin, Germany
| | - Matthew E Larkum
- Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany.,Neurocure Center for Excellence, Charité Universitätsmedizin Berlin, Germany
| | | | - Frank Furnari
- Ludwig Cancer Institute, San Diego, USA.,University of California San Diego, La Jolla, USA
| | - Britta J Eickholt
- Institute for Biochemistry, Charité Universitätsmedizin Berlin, Germany.,Neurocure Center for Excellence, Charité Universitätsmedizin Berlin, Germany
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23
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Tian D, Izumi SI. Transcranial Magnetic Stimulation and Neocortical Neurons: The Micro-Macro Connection. Front Neurosci 2022; 16:866245. [PMID: 35495053 PMCID: PMC9039343 DOI: 10.3389/fnins.2022.866245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 02/28/2022] [Indexed: 12/20/2022] Open
Abstract
Understanding the operation of cortical circuits is an important and necessary task in both neuroscience and neurorehabilitation. The functioning of the neocortex results from integrative neuronal activity, which can be probed non-invasively by transcranial magnetic stimulation (TMS). Despite a clear indication of the direct involvement of cortical neurons in TMS, no explicit connection model has been made between the microscopic neuronal landscape and the macroscopic TMS outcome. Here we have performed an integrative review of multidisciplinary evidence regarding motor cortex neurocytology and TMS-related neurophysiology with the aim of elucidating the micro–macro connections underlying TMS. Neurocytological evidence from animal and human studies has been reviewed to describe the landscape of the cortical neurons covering the taxonomy, morphology, circuit wiring, and excitatory–inhibitory balance. Evidence from TMS studies in healthy humans is discussed, with emphasis on the TMS pulse and paradigm selectivity that reflect the underlying neural circuitry constitution. As a result, we propose a preliminary neuronal model of the human motor cortex and then link the TMS mechanisms with the neuronal model by stimulus intensity, direction of induced current, and paired-pulse timing. As TMS bears great developmental potential for both a probe and modulator of neural network activity and neurotransmission, the connection model will act as a foundation for future combined studies of neurocytology and neurophysiology, as well as the technical advances and application of TMS.
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Affiliation(s)
- Dongting Tian
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduates School of Medicine, Sendai, Japan
- *Correspondence: Dongting Tian,
| | - Shin-Ichi Izumi
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduates School of Medicine, Sendai, Japan
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
- Shin-Ichi Izumi,
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24
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Breuer TM, Krieger P. Sensory deprivation leads to subpopulation-specific changes in layer 6 corticothalamic cells. Eur J Neurosci 2021; 55:566-588. [PMID: 34927292 DOI: 10.1111/ejn.15572] [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: 04/14/2021] [Revised: 12/12/2021] [Accepted: 12/14/2021] [Indexed: 12/01/2022]
Abstract
The effect of sensory deprivation on anatomical and physiological properties in two genetically defined types of layer 6 corticothalamic pyramidal cells in mouse somatosensory barrel cortex was investigated using in vitro electrophysiology. The two types analysed were the L6-Ntsr1 subtype, found preferentially in the upper region of layer 6 and projecting to both ventral posterior medial nucleus of the thalamus and posterior medial nucleus of the thalamus, and the L6-Drd1a subtype, located mostly in the lower regions of layer 6 and projecting to posterior medial nucleus. We found that the apical dendrite in L6-Ntsr1 cells is longer and more branched, compared to L6-Drd1a cells, and that the increase in firing frequency with increasing current stimulation is steeper in L6-Drd1a cells. Sensory deprivation was achieved clipping one row of whiskers from birth until the day of experiment (16 ± 2 days). Mice of this age are actively exploring. In L6-Ntsr1, but not in L6-Drd1a cells, sensory deprivation decreased apical and basal dendrite outgrowth, and calcium influx evoked by backpropagating action potentials. These results contribute to the ongoing functional characterisation of corticothalamic layer 6 cells and indicate differences in the postnatal cortical refinement of two distinct corticothalamic circuits.
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Affiliation(s)
| | - Patrik Krieger
- Department of Systems Neuroscience, Faculty of Medicine; Ruhr University Bochum, Germany
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25
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Castejon C, Martin-Cortecero J, Nuñez A. Higher-Order Thalamic Encoding of Somatosensory Patterns and Bilateral Events. Front Neural Circuits 2021; 15:752804. [PMID: 34759802 PMCID: PMC8573422 DOI: 10.3389/fncir.2021.752804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/30/2021] [Indexed: 11/13/2022] Open
Abstract
The function of the higher-order sensory thalamus remains unclear. Here, the posterior medial (POm) nucleus of the thalamus was examined by in vivo extracellular recordings in anesthetized rats across a variety of contralateral, ipsilateral, and bilateral whisker sensory patterns. We found that POm was highly sensitive to multiwhisker stimuli involving diverse spatiotemporal interactions. Accurate increases in POm activity were produced during the overlapping time between spatial signals reflecting changes in the spatiotemporal structure of sensory patterns. In addition, our results showed for first time that POm was also able to respond to tactile stimulation of ipsilateral whiskers. This finding challenges the notion that the somatosensory thalamus only computes unilateral stimuli. We found that POm also integrates signals from both whisker pads and described how this integration is generated. Our results showed that ipsilateral activity reached one POm indirectly from the other POm and demonstrated a transmission of sensory activity between both nuclei through a functional POm-POm loop formed by thalamocortical, interhemispheric, and corticothalamic projections. The implication of different cortical areas was investigated revealing that S1 plays a central role in this POm-POm loop. Accordingly, the subcortical and cortical inputs allow POm but not the ventral posteromedial thalamic nucleus (VPM) to have sensory information from both sides of the body. This finding is in agreement with the higher-order nature of POm and can be considered to functionally differentiate and classify these thalamic nuclei. A possible functional role of these higher-order thalamic patterns of integrated activity in brain function is discussed.
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Affiliation(s)
- Carlos Castejon
- Department of Anatomy, Histology and Neuroscience, Autónoma de Madrid University, Madrid, Spain
| | - Jesus Martin-Cortecero
- Department of Anatomy, Histology and Neuroscience, Autónoma de Madrid University, Madrid, Spain.,Institute of Physiology and Pathophysiology, Medical Biophysics, Heidelberg University, Heidelberg, Germany
| | - Angel Nuñez
- Department of Anatomy, Histology and Neuroscience, Autónoma de Madrid University, Madrid, Spain
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26
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Martinetti LE, Bonekamp KE, Autio DM, Kim HH, Crandall SR. Short-Term Facilitation of Long-Range Corticocortical Synapses Revealed by Selective Optical Stimulation. Cereb Cortex 2021; 32:1932-1949. [PMID: 34519352 PMCID: PMC9070351 DOI: 10.1093/cercor/bhab325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/10/2021] [Accepted: 08/11/2021] [Indexed: 11/14/2022] Open
Abstract
Short-term plasticity regulates the strength of central synapses as a function of previous activity. In the neocortex, direct synaptic interactions between areas play a central role in cognitive function, but the activity-dependent regulation of these long-range corticocortical connections and their impact on a postsynaptic target neuron is unclear. Here, we use an optogenetic strategy to study the connections between mouse primary somatosensory and motor cortex. We found that short-term facilitation was strong in both corticocortical synapses, resulting in far more sustained responses than local intracortical and thalamocortical connections. A major difference between pathways was that the synaptic strength and magnitude of facilitation were distinct for individual excitatory cells located across all cortical layers and specific subtypes of GABAergic neurons. Facilitation was dependent on the presynaptic calcium sensor synaptotagmin-7 and altered by several optogenetic approaches. Current-clamp recordings revealed that during repetitive activation, the short-term dynamics of corticocortical synapses enhanced the excitability of layer 2/3 pyramidal neurons, increasing the probability of spiking with activity. Furthermore, the properties of the connections linking primary with secondary somatosensory cortex resemble those between somatosensory-motor areas. These short-term changes in transmission properties suggest long-range corticocortical synapses are specialized for conveying information over relatively extended periods.
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Affiliation(s)
| | | | - Dawn M Autio
- Department of Physiology, Michigan State University, East Lansing, MI 48824, USA
| | - Hye-Hyun Kim
- Department of Physiology, Michigan State University, East Lansing, MI 48824, USA
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27
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Antunes FM, Malmierca MS. Corticothalamic Pathways in Auditory Processing: Recent Advances and Insights From Other Sensory Systems. Front Neural Circuits 2021; 15:721186. [PMID: 34489648 PMCID: PMC8418311 DOI: 10.3389/fncir.2021.721186] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 07/28/2021] [Indexed: 11/24/2022] Open
Abstract
The corticothalamic (CT) pathways emanate from either Layer 5 (L5) or 6 (L6) of the neocortex and largely outnumber the ascending, thalamocortical pathways. The CT pathways provide the anatomical foundations for an intricate, bidirectional communication between thalamus and cortex. They act as dynamic circuits of information transfer with the ability to modulate or even drive the response properties of target neurons at each synaptic node of the circuit. L6 CT feedback pathways enable the cortex to shape the nature of its driving inputs, by directly modulating the sensory message arriving at the thalamus. L5 CT pathways can drive the postsynaptic neurons and initiate a transthalamic corticocortical circuit by which cortical areas communicate with each other. For this reason, L5 CT pathways place the thalamus at the heart of information transfer through the cortical hierarchy. Recent evidence goes even further to suggest that the thalamus via CT pathways regulates functional connectivity within and across cortical regions, and might be engaged in cognition, behavior, and perceptual inference. As descending pathways that enable reciprocal and context-dependent communication between thalamus and cortex, we venture that CT projections are particularly interesting in the context of hierarchical perceptual inference formulations such as those contemplated in predictive processing schemes, which so far heavily rely on cortical implementations. We discuss recent proposals suggesting that the thalamus, and particularly higher order thalamus via transthalamic pathways, could coordinate and contextualize hierarchical inference in cortical hierarchies. We will explore these ideas with a focus on the auditory system.
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Affiliation(s)
- Flora M. Antunes
- Cognitive and Auditory Neuroscience Laboratory (CANELAB), Institute of Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain
- Institute for Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain
| | - Manuel S. Malmierca
- Cognitive and Auditory Neuroscience Laboratory (CANELAB), Institute of Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain
- Institute for Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain
- Department of Cell Biology and Pathology, School of Medicine, University of Salamanca, Salamanca, Spain
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28
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Ghezzi F, Marques-Smith A, Anastasiades PG, Lyngholm D, Vagnoni C, Rowett A, Parameswaran G, Hoerder-Suabedissen A, Nakagawa Y, Molnar Z, Butt SJ. Non-canonical role for Lpar1-EGFP subplate neurons in early postnatal mouse somatosensory cortex. eLife 2021; 10:60810. [PMID: 34251335 PMCID: PMC8294844 DOI: 10.7554/elife.60810] [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: 07/07/2020] [Accepted: 07/09/2021] [Indexed: 11/13/2022] Open
Abstract
Subplate neurons (SPNs) are thought to play a role in nascent sensory processing in neocortex. To better understand how heterogeneity within this population relates to emergent function, we investigated the synaptic connectivity of Lpar1-EGFP SPNs through the first postnatal week in whisker somatosensory cortex (S1BF). These SPNs comprise of two morphological subtypes: fusiform SPNs with local axons and pyramidal SPNs with axons that extend through the marginal zone. The former receive translaminar synaptic input up until the emergence of the whisker barrels, a timepoint coincident with significant cell death. In contrast, pyramidal SPNs receive local input from the subplate at early ages but then - during the later time window - acquire input from overlying cortex. Combined electrical and optogenetic activation of thalamic afferents identified that Lpar1-EGFP SPNs receive sparse thalamic innervation. These data reveal components of the postnatal network that interpret sparse thalamic input to direct the emergent columnar structure of S1BF.
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Affiliation(s)
- Filippo Ghezzi
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Andre Marques-Smith
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Paul G Anastasiades
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Daniel Lyngholm
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Cristiana Vagnoni
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Alexandra Rowett
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Gokul Parameswaran
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Anna Hoerder-Suabedissen
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Yasushi Nakagawa
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
| | - Zoltan Molnar
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
| | - Simon Jb Butt
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, United Kingdom
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29
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Yook JS, Kim J, Kim J. Convergence Circuit Mapping: Genetic Approaches From Structure to Function. Front Syst Neurosci 2021; 15:688673. [PMID: 34234652 PMCID: PMC8255632 DOI: 10.3389/fnsys.2021.688673] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/28/2021] [Indexed: 12/22/2022] Open
Abstract
Understanding the complex neural circuits that underpin brain function and behavior has been a long-standing goal of neuroscience. Yet this is no small feat considering the interconnectedness of neurons and other cell types, both within and across brain regions. In this review, we describe recent advances in mouse molecular genetic engineering that can be used to integrate information on brain activity and structure at regional, cellular, and subcellular levels. The convergence of structural inputs can be mapped throughout the brain in a cell type-specific manner by antero- and retrograde viral systems expressing various fluorescent proteins and genetic switches. Furthermore, neural activity can be manipulated using opto- and chemo-genetic tools to interrogate the functional significance of this input convergence. Monitoring neuronal activity is obtained with precise spatiotemporal resolution using genetically encoded sensors for calcium changes and specific neurotransmitters. Combining these genetically engineered mapping tools is a compelling approach for unraveling the structural and functional brain architecture of complex behaviors and malfunctioned states of neurological disorders.
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Affiliation(s)
- Jang Soo Yook
- Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, South Korea
| | - Jihyun Kim
- Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, South Korea.,Department of Integrated Biomedical and Life Sciences, Graduate School, Korea University, Seoul, South Korea
| | - Jinhyun Kim
- Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, South Korea.,Department of Integrated Biomedical and Life Sciences, Graduate School, Korea University, Seoul, South Korea
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30
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Liang Y, Fan JL, Sun W, Lu R, Chen M, Ji N. A Distinct Population of L6 Neurons in Mouse V1 Mediate Cross-Callosal Communication. Cereb Cortex 2021; 31:4259-4273. [PMID: 33987642 DOI: 10.1093/cercor/bhab084] [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: 11/12/2022] Open
Abstract
Through the corpus callosum, interhemispheric communication is mediated by callosal projection (CP) neurons. Using retrograde labeling, we identified a population of layer 6 (L6) excitatory neurons as the main conveyer of transcallosal information in the monocular zone of the mouse primary visual cortex (V1). Distinct from L6 corticothalamic (CT) population, V1 L6 CP neurons contribute to an extensive reciprocal network across multiple sensory cortices over two hemispheres. Receiving both local and long-range cortical inputs, they encode orientation, direction, and receptive field information, while are also highly spontaneous active. The spontaneous activity of L6 CP neurons exhibits complex relationships with brain states and stimulus presentation, distinct from the spontaneous activity patterns of the CT population. The anatomical and functional properties of these L6 CP neurons enable them to broadcast visual and nonvisual information across two hemispheres, and thus may play a role in regulating and coordinating brain-wide activity events.
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Affiliation(s)
- Yajie Liang
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.,Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, MD 201210, USA
| | - Jiang Lan Fan
- UCSF-UC Berkeley Joint PhD Program in Bioengineering, University of California, Berkeley, CA 94720, USA
| | - Wenzhi Sun
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.,iHuman Institute, ShanghaiTech University, Shanghai 201210, China.,Chinese Institute for Brain Research, Beijing 102206, China
| | - Rongwen Lu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.,National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ming Chen
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China
| | - Na Ji
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.,Department of Physics, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA
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31
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Anastasiades PG, Carter AG. Circuit organization of the rodent medial prefrontal cortex. Trends Neurosci 2021; 44:550-563. [PMID: 33972100 DOI: 10.1016/j.tins.2021.03.006] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 03/12/2021] [Accepted: 03/31/2021] [Indexed: 12/14/2022]
Abstract
The prefrontal cortex (PFC) orchestrates higher brain function and becomes disrupted in many mental health disorders. The rodent medial PFC (mPFC) possesses an enormous variety of projection neurons and interneurons. These cells are engaged by long-range inputs from other brain regions involved in cognition, motivation, and emotion. They also communicate in the local network via specific connections between excitatory and inhibitory cells. In this review, we describe the cellular diversity of the rodent mPFC, the impact of long-range afferents, and the specificity of local microcircuits. We highlight similarities with and differences between other cortical areas, illustrating how the circuit organization of the mPFC may give rise to its unique functional roles.
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Affiliation(s)
- Paul G Anastasiades
- Department of Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
| | - Adam G Carter
- Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003, USA.
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32
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Untangling the cortico-thalamo-cortical loop: cellular pieces of a knotty circuit puzzle. Nat Rev Neurosci 2021; 22:389-406. [PMID: 33958775 DOI: 10.1038/s41583-021-00459-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2021] [Indexed: 12/22/2022]
Abstract
Functions of the neocortex depend on its bidirectional communication with the thalamus, via cortico-thalamo-cortical (CTC) loops. Recent work dissecting the synaptic connectivity in these loops is generating a clearer picture of their cellular organization. Here, we review findings across sensory, motor and cognitive areas, focusing on patterns of cell type-specific synaptic connections between the major types of cortical and thalamic neurons. We outline simple and complex CTC loops, and note features of these loops that appear to be general versus specialized. CTC loops are tightly interlinked with local cortical and corticocortical (CC) circuits, forming extended chains of loops that are probably critical for communication across hierarchically organized cerebral networks. Such CTC-CC loop chains appear to constitute a modular unit of organization, serving as scaffolding for area-specific structural and functional modifications. Inhibitory neurons and circuits are embedded throughout CTC loops, shaping the flow of excitation. We consider recent findings in the context of established CTC and CC circuit models, and highlight current efforts to pinpoint cell type-specific mechanisms in CTC loops involved in consciousness and perception. As pieces of the connectivity puzzle fall increasingly into place, this knowledge can guide further efforts to understand structure-function relationships in CTC loops.
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33
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Brown APY, Cossell L, Strom M, Tyson AL, Vélez-Fort M, Margrie TW. Analysis of segmentation ontology reveals the similarities and differences in connectivity onto L2/3 neurons in mouse V1. Sci Rep 2021; 11:4983. [PMID: 33654118 PMCID: PMC7925549 DOI: 10.1038/s41598-021-82353-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 01/15/2021] [Indexed: 12/02/2022] Open
Abstract
Quantitatively comparing brain-wide connectivity of different types of neuron is of vital importance in understanding the function of the mammalian cortex. Here we have designed an analytical approach to examine and compare datasets from hierarchical segmentation ontologies, and applied it to long-range presynaptic connectivity onto excitatory and inhibitory neurons, mainly located in layer 2/3 (L2/3), of mouse primary visual cortex (V1). We find that the origins of long-range connections onto these two general cell classes-as well as their proportions-are quite similar, in contrast to the inputs on to a cell type in L6. These anatomical data suggest that distal inputs received by the general excitatory and inhibitory classes of neuron in L2/3 overlap considerably.
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Affiliation(s)
- Alexander P Y Brown
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London, W1T 4JG, UK
| | - Lee Cossell
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London, W1T 4JG, UK
| | - Molly Strom
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London, W1T 4JG, UK
| | - Adam L Tyson
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London, W1T 4JG, UK
| | - Mateo Vélez-Fort
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London, W1T 4JG, UK
| | - Troy W Margrie
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London, W1T 4JG, UK.
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34
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Doron G, Shin JN, Takahashi N, Drüke M, Bocklisch C, Skenderi S, de Mont L, Toumazou M, Ledderose J, Brecht M, Naud R, Larkum ME. Perirhinal input to neocortical layer 1 controls learning. Science 2021; 370:370/6523/eaaz3136. [PMID: 33335033 DOI: 10.1126/science.aaz3136] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 08/27/2020] [Accepted: 10/23/2020] [Indexed: 12/28/2022]
Abstract
Hippocampal output influences memory formation in the neocortex, but this process is poorly understood because the precise anatomical location and the underlying cellular mechanisms remain elusive. Here, we show that perirhinal input, predominantly to sensory cortical layer 1 (L1), controls hippocampal-dependent associative learning in rodents. This process was marked by the emergence of distinct firing responses in defined subpopulations of layer 5 (L5) pyramidal neurons whose tuft dendrites receive perirhinal inputs in L1. Learning correlated with burst firing and the enhancement of dendritic excitability, and it was suppressed by disruption of dendritic activity. Furthermore, bursts, but not regular spike trains, were sufficient to retrieve learned behavior. We conclude that hippocampal information arriving at L5 tuft dendrites in neocortical L1 mediates memory formation in the neocortex.
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Affiliation(s)
- Guy Doron
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany.
| | - Jiyun N Shin
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Naoya Takahashi
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Moritz Drüke
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Christina Bocklisch
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Salina Skenderi
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Lisa de Mont
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Maria Toumazou
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Julia Ledderose
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany
| | - Michael Brecht
- Bernstein Center for Computational Neuroscience, Humboldt-Universität zu Berlin, D-10115 Berlin, Germany.,NeuroCure Cluster, Charité - Universitätsmedizin Berlin, D-10117 Berlin, Germany
| | - Richard Naud
- University of Ottawa Brain and Mind 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
| | - Matthew E Larkum
- Institute for Biology, Humboldt-Universität zu Berlin, D-10117 Berlin, Germany. .,NeuroCure Cluster, Charité - Universitätsmedizin Berlin, D-10117 Berlin, Germany
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35
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Tsai SH, Tsao CY, Lee LJ. Altered White Matter and Layer VIb Neurons in Heterozygous Disc1 Mutant, a Mouse Model of Schizophrenia. Front Neuroanat 2020; 14:605029. [PMID: 33384588 PMCID: PMC7769951 DOI: 10.3389/fnana.2020.605029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 11/24/2020] [Indexed: 11/13/2022] Open
Abstract
Increased white matter neuron density has been associated with neuropsychiatric disorders including schizophrenia. However, the pathogenic features of these neurons are still largely unknown. Subplate neurons, the earliest generated neurons in the developing cortex have also been associated with schizophrenia and autism. The link between these neurons and mental disorders is also not well established. Since cortical layer VIb neurons are believed to be the remnant of subplate neurons in the adult rodent brain, in this study, we aimed to examine the cytoarchitecture of neurons in cortical layer VIb and the underlying white matter in heterozygous Disc1 mutant (Het) mice, a mouse model of schizophrenia. In the white matter, the number of NeuN-positive neurons was quite low in the external capsule; however, the density of these cells was found increased (54%) in Het mice compared with wildtype (WT) littermates. The density of PV-positive neurons was unchanged in the mutants. In the cortical layer VIb, the density of CTGF-positive neurons increased (21.5%) in Het mice, whereas the number of Cplx3-positive cells reduced (16.1%) in these mutants, compared with WT mice. Layer VIb neurons can be classified by their morphological characters. The morphology of Type I pyramidal neurons was comparable between genotypes while the dendritic length and complexity of Type II multipolar neurons were significantly reduced in Het mice. White matter neurons and layer VIb neurons receive synaptic inputs and modulate the process of sensory information and sleep/arousal pattern. Aberrances of these neurons in Disc1 mutants implies altered brain functions in these mice.
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Affiliation(s)
- Shin-Hwa Tsai
- School of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chih-Yu Tsao
- Graduate Institute of Anatomy and Cell Biology, National Taiwan University, Taipei, Taiwan
| | - Li-Jen Lee
- School of Medicine, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Anatomy and Cell Biology, National Taiwan University, Taipei, Taiwan
- Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan
- Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan
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36
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Bruguier H, Suarez R, Manger P, Hoerder-Suabedissen A, Shelton AM, Oliver DK, Packer AM, Ferran JL, García-Moreno F, Puelles L, Molnár Z. In search of common developmental and evolutionary origin of the claustrum and subplate. J Comp Neurol 2020; 528:2956-2977. [PMID: 32266722 DOI: 10.1002/cne.24922] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 02/06/2023]
Abstract
The human claustrum, a major hub of widespread neocortical connections, is a thin, bilateral sheet of gray matter located between the insular cortex and the striatum. The subplate is a largely transient cortical structure that contains some of the earliest generated neurons of the cerebral cortex and has important developmental functions to establish intra- and extracortical connections. In human and macaque some subplate cells undergo regulated cell death, but some remain as interstitial white matter cells. In mouse and rat brains a compact layer is formed, Layer 6b, and it remains underneath the cortex, adjacent to the white matter. Whether Layer 6b in rodents is homologous to primate subplate or interstitial white matter cells is still debated. Gene expression patterns, such as those of Nurr1/Nr4a2, have suggested that the rodent subplate and the persistent subplate cells in Layer 6b and the claustrum might have similar origins. Moreover, the birthdates of the claustrum and Layer 6b are similarly precocious in mice. These observations prompted our speculations on the common developmental and evolutionary origin of the claustrum and the subplate. Here we systematically compare the currently available data on cytoarchitecture, evolutionary origin, gene expression, cell types, birthdates, neurogenesis, lineage and migration, circuit connectivity, and cell death of the neurons that contribute to the claustrum and subplate. Based on their similarities and differences we propose a partially common early evolutionary origin of the cells that become claustrum and subplate, a likely scenario that is shared in these cell populations across all amniotes.
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Affiliation(s)
- Hannah Bruguier
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Rodrigo Suarez
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Paul Manger
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | - Andrew M Shelton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - David K Oliver
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Adam M Packer
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - José L Ferran
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - Fernando García-Moreno
- Achucarro Basque Center for Neuroscience, Zamudio, Spain.,IKERBASQUE Foundation, Bilbao, Spain
| | - Luis Puelles
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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37
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Molnár Z, Luhmann HJ, Kanold PO. Transient cortical circuits match spontaneous and sensory-driven activity during development. Science 2020; 370:370/6514/eabb2153. [PMID: 33060328 DOI: 10.1126/science.abb2153] [Citation(s) in RCA: 145] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
At the earliest developmental stages, spontaneous activity synchronizes local and large-scale cortical networks. These networks form the functional template for the establishment of global thalamocortical networks and cortical architecture. The earliest connections are established autonomously. However, activity from the sensory periphery reshapes these circuits as soon as afferents reach the cortex. The early-generated, largely transient neurons of the subplate play a key role in integrating spontaneous and sensory-driven activity. Early pathological conditions-such as hypoxia, inflammation, or exposure to pharmacological compounds-alter spontaneous activity patterns, which subsequently induce disturbances in cortical network activity. This cortical dysfunction may lead to local and global miswiring and, at later stages, can be associated with neurological and psychiatric conditions.
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Affiliation(s)
- Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Parks Road, Oxford OX1 3PT, UK.
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, Mainz 55128, Germany.
| | - Patrick O Kanold
- Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, 720 Rutland Avenue, MRB 379, Baltimore, MD 21205, USA. .,Johns Hopkins University Kavli Neuroscience Discovery Institute, Baltimore, MD 21205, USA
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38
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Buchan MJ. A subpopulation of L6b neurons provides driver-like input to the posteromedial thalamus. J Physiol 2020; 598:5313-5315. [PMID: 32857864 DOI: 10.1113/jp280472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 08/25/2020] [Indexed: 12/18/2022] Open
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Takahashi N, Ebner C, Sigl-Glöckner J, Moberg S, Nierwetberg S, Larkum ME. Active dendritic currents gate descending cortical outputs in perception. Nat Neurosci 2020; 23:1277-1285. [DOI: 10.1038/s41593-020-0677-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 06/23/2020] [Indexed: 12/27/2022]
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40
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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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41
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Kostović I. The enigmatic fetal subplate compartment forms an early tangential cortical nexus and provides the framework for construction of cortical connectivity. Prog Neurobiol 2020; 194:101883. [PMID: 32659318 DOI: 10.1016/j.pneurobio.2020.101883] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 06/05/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022]
Abstract
The most prominent transient compartment of the primate fetal cortex is the deep, cell-sparse, synapse-containing subplate compartment (SPC). The developmental role of the SPC and its extraordinary size in humans remain enigmatic. This paper evaluates evidence on the development and connectivity of the SPC and discusses its role in the pathogenesis of neurodevelopmental disorders. A synthesis of data shows that the subplate becomes a prominent compartment by its expansion from the deep cortical plate (CP), appearing well-delineated on MR scans and forming a tangential nexus across the hemisphere, consisting of an extracellular matrix, randomly distributed postmigratory neurons, multiple branches of thalamic and long corticocortical axons. The SPC generates early spontaneous non-synaptic and synaptic activity and mediates cortical response upon thalamic stimulation. The subplate nexus provides large-scale interareal connectivity possibly underlying fMR resting-state activity, before corticocortical pathways are established. In late fetal phase, when synapses appear within the CP, transient the SPC coexists with permanent circuitry. The histogenetic role of the SPC is to provide interactive milieu and capacity for guidance, sorting, "waiting" and target selection of thalamocortical and corticocortical pathways. The new evolutionary role of the SPC and its remnant white matter neurons is linked to the increasing number of associative pathways in the human neocortex. These roles attributed to the SPC are regulated using a spatiotemporal gene expression during critical periods, when pathogenic factors may disturb vulnerable circuitry of the SPC, causing neurodevelopmental cognitive circuitry disorders.
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Affiliation(s)
- Ivica Kostović
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Scientific Centre of Excellence for Basic, Clinical and Translational Neuroscience, Salata 12, 10000 Zagreb, Croatia.
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42
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Tukker JJ, Beed P, Schmitz D, Larkum ME, Sachdev RNS. Up and Down States and Memory Consolidation Across Somatosensory, Entorhinal, and Hippocampal Cortices. Front Syst Neurosci 2020; 14:22. [PMID: 32457582 PMCID: PMC7227438 DOI: 10.3389/fnsys.2020.00022] [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: 01/31/2020] [Accepted: 04/03/2020] [Indexed: 01/01/2023] Open
Abstract
In the course of a day, brain states fluctuate, from conscious awake information-acquiring states to sleep states, during which previously acquired information is further processed and stored as memories. One hypothesis is that memories are consolidated and stored during "offline" states such as sleep, a process thought to involve transfer of information from the hippocampus to other cortical areas. Up and Down states (UDS), patterns of activity that occur under anesthesia and sleep states, are likely to play a role in this process, although the nature of this role remains unclear. Here we review what is currently known about these mechanisms in three anatomically distinct but interconnected cortical areas: somatosensory cortex, entorhinal cortex, and the hippocampus. In doing so, we consider the role of this activity in the coordination of "replay" during sleep states, particularly during hippocampal sharp-wave ripples. We conclude that understanding the generation and propagation of UDS may provide key insights into the cortico-hippocampal dialogue linking archi- and neocortical areas during memory formation.
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Affiliation(s)
- John J Tukker
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Neuroscience Research Center, Berlin, Germany.,German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | - Prateep Beed
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Neuroscience Research Center, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
| | - Dietmar Schmitz
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Neuroscience Research Center, Berlin, Germany.,German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany.,Berlin Institute of Health, Berlin, Germany.,Cluster of Excellence NeuroCure, Berlin, Germany.,Einstein Center for Neurosciences Berlin, Berlin, Germany
| | - Matthew E Larkum
- Cluster of Excellence NeuroCure, Berlin, Germany.,Einstein Center for Neurosciences Berlin, Berlin, Germany.,Institut für Biologie, Humboldt Universität, Berlin, Germany
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Tantirigama MLS, Zolnik T, Judkewitz B, Larkum ME, Sachdev RNS. Perspective on the Multiple Pathways to Changing Brain States. Front Syst Neurosci 2020; 14:23. [PMID: 32457583 PMCID: PMC7225277 DOI: 10.3389/fnsys.2020.00023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 04/06/2020] [Indexed: 11/13/2022] Open
Abstract
In this review article, we highlight several disparate ideas that are linked to changes in brain state (i.e., sleep to arousal, Down to Up, synchronized to de-synchronized). In any discussion of the brain state, we propose that the cortical pyramidal neuron has a central position. EEG recordings, which typically assess brain state, predominantly reflect the activity of cortical pyramidal neurons. This means that the dominant rhythmic activity that characterizes a particular brain state ultimately has to manifest globally across the pyramidal neuron population. During state transitions, it is the long-range connectivity of these neurons that broadcast the resultant changes in activity to many subcortical targets. Structures like the thalamus, brainstem/hypothalamic neuromodulatory systems, and respiratory systems can also strongly influence brain state, and for many decades we have been uncovering bidirectional pathways that link these structures to state changes in the cerebral cortex. More recently, movement and active behaviors have emerged as powerful drivers of state changes. Each of these systems involve different circuits distributed across the brain. Yet, for a system-wide change in brain state, there must be a collaboration between these circuits that reflects and perhaps triggers the transition between brain states. As we expand our understanding of how brain state changes, our current challenge is to understand how these diverse sets of circuits and pathways interact to produce the changes observed in cortical pyramidal neurons.
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Affiliation(s)
| | | | | | - Matthew E. Larkum
- Institut für Biologie, Neurocure Center for Excellence, Charité Universitätsmedizin Berlin & Humboldt Universität, Berlin, Germany
| | - Robert N. S. Sachdev
- Institut für Biologie, Neurocure Center for Excellence, Charité Universitätsmedizin Berlin & Humboldt Universität, Berlin, Germany
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