1
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Sgourdou P, Schaffler M, Choi K, McCall NM, Burdge J, Williams J, Corder G, Fuccillo MV, Abdus-Saboor I, Epstein DJ. Impaired pain in mice lacking first-order posterior medial thalamic neurons. Pain 2024:00006396-990000000-00692. [PMID: 39190341 DOI: 10.1097/j.pain.0000000000003325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 06/04/2024] [Indexed: 08/28/2024]
Abstract
ABSTRACT The thalamus plays an important role in sensory and motor information processing by mediating communication between the periphery and the cerebral cortex. Alterations in thalamic development have profound consequences on sensory and motor function. In this study, we investigated a mouse model in which thalamic nuclei formation is disrupted because of the absence of Sonic hedgehog (Shh) expression from 2 key signaling centers that are required for embryonic forebrain development. The resulting defects observed in distinct thalamic sensory nuclei in Shh mutant embryos persisted into adulthood prompting us to examine their effect on behavioral responses to somatosensory stimulation. Our findings reveal a role for first-order posterior medial thalamic neurons and their projections to layer 4 of the secondary somatosensory cortex in the transmission of nociceptive information. Together, these results establish a connection between a neurodevelopmental lesion in the thalamus and a modality-specific disruption in pain perception.
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Affiliation(s)
- Paraskevi Sgourdou
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Melanie Schaffler
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Kyuhyun Choi
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Nora M McCall
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Justin Burdge
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
- Zuckerman Mind Brain Behavior Institute, Department of Biological Sciences, Columbia University, Jerome L. Greene Center, New York, NY, United States
| | - Joelle Williams
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gregory Corder
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Marc V Fuccillo
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ishmail Abdus-Saboor
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
- Zuckerman Mind Brain Behavior Institute, Department of Biological Sciences, Columbia University, Jerome L. Greene Center, New York, NY, United States
| | - Douglas J Epstein
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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2
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Petty GH, Bruno RM. Attentional modulation of secondary somatosensory and visual thalamus of mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.22.586242. [PMID: 38585833 PMCID: PMC10996504 DOI: 10.1101/2024.03.22.586242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Each sensory modality has its own primary and secondary thalamic nuclei. While the primary thalamic nuclei are well understood to relay sensory information from the periphery to the cortex, the role of secondary sensory nuclei is elusive. One hypothesis has been that secondary nuclei may support feature-based attention. If this is true, one would also expect the activity in different nuclei to reflect the degree to which modalities are or are not behaviorally relevant in a task. We trained head-fixed mice to attend to one sensory modality while ignoring a second modality, namely to attend to touch and ignore vision, or vice versa. Arrays were used to record simultaneously from secondary somatosensory thalamus (POm) and secondary visual thalamus (LP). In mice trained to respond to tactile stimuli and ignore visual stimuli, POm was robustly activated by touch and largely unresponsive to visual stimuli. A different pattern was observed when mice were trained to respond to visual stimuli and ignore touch, with POm now more robustly activated during visual trials. This POm activity was not explained by differences in movements (i.e., whisking, licking, pupil dilation) resulting from the two tasks. Post hoc histological reconstruction of array tracks through POm revealed that subregions varied in their degree of plasticity. LP exhibited similar phenomena. We conclude that behavioral training reshapes activity in secondary thalamic nuclei. Secondary nuclei may respond to behaviorally relevant, reward-predicting stimuli regardless of stimulus modality.
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Affiliation(s)
- Gordon H Petty
- Department of Neuroscience, Columbia University, New York, NY 10027 USA
| | - Randy M Bruno
- Department of Neuroscience, Columbia University, New York, NY 10027 USA
- Department of Physiology, Anatomy, & Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
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3
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Arena G, Londei F, Ceccarelli F, Ferrucci L, Borra E, Genovesio A. Disentangling the identity of the zona incerta: a review of the known connections and latest implications. Ageing Res Rev 2024; 93:102140. [PMID: 38008404 DOI: 10.1016/j.arr.2023.102140] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 11/28/2023]
Abstract
The zona incerta (ZI) is a subthalamic region composed by loosely packed neurochemically mixed neurons, juxtaposed to the main ascending and descending bundles. The extreme neurochemical diversity that characterizes this area, together with the diffuseness of its connections with the entire neuraxis and its hard-to-reach positioning in the brain caused the ZI to keep its halo of mystery for over a century. However, in the last decades, a rich albeit fragmentary body of knowledge regarding both the incertal anatomical connections and functional implications has been built mostly based on rodent studies and its lack of cohesion makes difficult to depict an integrated, exhaustive picture regarding the ZI and its roles. This review aims to provide a unified resource that summarizes the current knowledge regarding the anatomical profile of interactions of the ZI in rodents and non-human primates and the functional significance of its connections, highlighting the aspects still unbeknown to research.
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Affiliation(s)
- Giulia Arena
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; PhD program in Behavioral Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Fabrizio Londei
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; PhD program in Behavioral Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Francesco Ceccarelli
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Lorenzo Ferrucci
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Elena Borra
- University of Parma, Department of Medicine and Surgery, Neuroscience Unit, Italy
| | - Aldo Genovesio
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
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4
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Petty GH, Kinnischtzke AK, Hong YK, Bruno RM. Effects of arousal and movement on secondary somatosensory and visual thalamus. eLife 2021; 10:67611. [PMID: 34842139 PMCID: PMC8660016 DOI: 10.7554/elife.67611] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 11/26/2021] [Indexed: 11/13/2022] Open
Abstract
Neocortical sensory areas have associated primary and secondary thalamic nuclei. While primary nuclei transmit sensory information to cortex, secondary nuclei remain poorly understood. We recorded juxtasomally from secondary somatosensory (POm) and visual (LP) nuclei of awake mice while tracking whisking and pupil size. POm activity correlated with whisking, but not precise whisker kinematics. This coarse movement modulation persisted after facial paralysis and thus was not due to sensory reafference. This phenomenon also continued during optogenetic silencing of somatosensory and motor cortex and after lesion of superior colliculus, ruling out a motor efference copy mechanism. Whisking and pupil dilation were strongly correlated, possibly reflecting arousal. Indeed LP, which is not part of the whisker system, tracked whisking equally well, further indicating that POm activity does not encode whisker movement per se. The semblance of movement-related activity is likely instead a global effect of arousal on both nuclei. We conclude that secondary thalamus monitors behavioral state, rather than movement, and may exist to alter cortical activity accordingly.
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Affiliation(s)
- Gordon H Petty
- Department of Neuroscience, Columbia University, New York, United States.,Kavli Institute for Brain Science, New York, United States.,Zuckerman Mind Brain Behavior Institute, New York, United States
| | - Amanda K Kinnischtzke
- Department of Neuroscience, Columbia University, New York, United States.,Kavli Institute for Brain Science, New York, United States.,Zuckerman Mind Brain Behavior Institute, New York, United States
| | - Y Kate Hong
- Department of Neuroscience, Columbia University, New York, United States.,Kavli Institute for Brain Science, New York, United States.,Zuckerman Mind Brain Behavior Institute, New York, United States
| | - Randy M Bruno
- Department of Neuroscience, Columbia University, New York, United States.,Kavli Institute for Brain Science, New York, United States.,Zuckerman Mind Brain Behavior Institute, New York, United States
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5
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Mease RA, Gonzalez AJ. Corticothalamic Pathways From Layer 5: Emerging Roles in Computation and Pathology. Front Neural Circuits 2021; 15:730211. [PMID: 34566583 PMCID: PMC8458899 DOI: 10.3389/fncir.2021.730211] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 08/10/2021] [Indexed: 11/29/2022] Open
Abstract
Large portions of the thalamus receive strong driving input from cortical layer 5 (L5) neurons but the role of this important pathway in cortical and thalamic computations is not well understood. L5-recipient "higher-order" thalamic regions participate in cortico-thalamo-cortical (CTC) circuits that are increasingly recognized to be (1) anatomically and functionally distinct from better-studied "first-order" CTC networks, and (2) integral to cortical activity related to learning and perception. Additionally, studies are beginning to elucidate the clinical relevance of these networks, as dysfunction across these pathways have been implicated in several pathological states. In this review, we highlight recent advances in understanding L5 CTC networks across sensory modalities and brain regions, particularly studies leveraging cell-type-specific tools that allow precise experimental access to L5 CTC circuits. We aim to provide a focused and accessible summary of the anatomical, physiological, and computational properties of L5-originating CTC networks, and outline their underappreciated contribution in pathology. We particularly seek to connect single-neuron and synaptic properties to network (dys)function and emerging theories of cortical computation, and highlight information processing in L5 CTC networks as a promising focus for computational studies.
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Affiliation(s)
- Rebecca A. Mease
- Institute of Physiology and Pathophysiology, Medical Biophysics, Heidelberg University, Heidelberg, Germany
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6
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An increase in dendritic plateau potentials is associated with experience-dependent cortical map reorganization. Proc Natl Acad Sci U S A 2021; 118:2024920118. [PMID: 33619110 PMCID: PMC7936269 DOI: 10.1073/pnas.2024920118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Here we describe a mechanism for cortical map plasticity. Classically, representational map changes are thought to be driven by changes within cortico-cortical circuits, e.g., Hebbian plasticity of synaptic circuits that lost vs. maintained an excitatory drive from the first-order thalamus, possibly steered by neuromodulatory forces from deep brain regions. Our work provides evidence for an additional gating mechanism, provided by plateau potentials, which are driven by higher-order thalamic feedback. Higher-order thalamic neurons are characterized by broad receptive fields, and the plateau potentials that they evoke strongly facilitate long-term potentiation and elicit spikes. We show that these features combined constitute a powerful driving force for the fusion or expansion of sensory representations within cortical maps. The organization of sensory maps in the cerebral cortex depends on experience, which drives homeostatic and long-term synaptic plasticity of cortico-cortical circuits. In the mouse primary somatosensory cortex (S1) afferents from the higher-order, posterior medial thalamic nucleus (POm) gate synaptic plasticity in layer (L) 2/3 pyramidal neurons via disinhibition and the production of dendritic plateau potentials. Here we address whether these thalamocortically mediated responses play a role in whisker map plasticity in S1. We find that trimming all but two whiskers causes a partial fusion of the representations of the two spared whiskers, concomitantly with an increase in the occurrence of POm-driven N-methyl-D-aspartate receptor-dependent plateau potentials. Blocking the plateau potentials restores the archetypical organization of the sensory map. Our results reveal a mechanism for experience-dependent cortical map plasticity in which higher-order thalamocortically mediated plateau potentials facilitate the fusion of normally segregated cortical representations.
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7
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Circuit mechanisms for cortical plasticity and learning. Semin Cell Dev Biol 2021; 125:68-75. [PMID: 34332885 DOI: 10.1016/j.semcdb.2021.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 11/22/2022]
Abstract
The cerebral cortex integrates sensory information with emotional states and internal representations to produce coherent percepts, form associations, and execute voluntary actions. For the cortex to optimize perception, its neuronal network needs to dynamically retrieve and encode new information. Over the last few decades, research has started to provide insight into how the cortex serves these functions. Building on classical Hebbian plasticity models, the latest hypotheses hold that throughout experience and learning, streams of feedforward, feedback, and modulatory information operate in selective and coordinated manners to alter the strength of synapses and ultimately change the response properties of cortical neurons. Here, we describe cortical plasticity mechanisms that involve the concerted action of feedforward and long-range feedback input onto pyramidal neurons as well as the implication of local disinhibitory circuit motifs in this process.
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8
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Nersisyan S, Bekisz M, Kublik E, Granseth B, Wróbel A. Cholinergic and Noradrenergic Modulation of Corticothalamic Synaptic Input From Layer 6 to the Posteromedial Thalamic Nucleus in the Rat. Front Neural Circuits 2021; 15:624381. [PMID: 33981204 PMCID: PMC8107268 DOI: 10.3389/fncir.2021.624381] [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: 10/31/2020] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
Cholinergic and noradrenergic neuromodulation of the synaptic transmission from cortical layer 6 of the primary somatosensory cortex to neurons in the posteromedial thalamic nucleus (PoM) was studied using an in vitro slice preparation from young rats. Cholinergic agonist carbachol substantially decreased the amplitudes of consecutive excitatory postsynaptic potentials (EPSPs) evoked by a 20 Hz five pulse train. The decreased amplitude effect was counteracted by a parallel increase of synaptic frequency-dependent facilitation. We found this modulation to be mediated by muscarinic acetylcholine receptors. In the presence of carbachol the amplitudes of the postsynaptic potentials showed a higher trial-to-trial coefficient of variation (CV), which suggested a presynaptic site of action for the modulation. To substantiate this finding, we measured the failure rate of the excitatory postsynaptic currents in PoM cells evoked by “pseudominimal” stimulation of corticothalamic input. A higher failure-rate in the presence of carbachol indicated decreased probability of transmitter release at the synapse. Activation of the noradrenergic modulatory system that was mimicked by application of norepinephrine did not affect the amplitude of the first EPSP evoked in the five-pulse train, but later EPSPs were diminished. This indicated a decrease of the synaptic frequency-dependent facilitation. Treatment with noradrenergic α-2 agonist clonidine, α-1 agonist phenylephrine, or β-receptor agonist isoproterenol showed that the modulation may partly rely on α-2 adrenergic receptors. CV analysis did not suggest a presynaptic action of norepinephrine. We conclude that cholinergic and noradrenergic modulation act as different variable dynamic controls for the corticothalamic mechanism of the frequency-dependent facilitation in PoM.
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Affiliation(s)
- Syune Nersisyan
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Marek Bekisz
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Ewa Kublik
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Björn Granseth
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Andrzej Wróbel
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.,Faculty of Philosophy, University of Warsaw, Warsaw, Poland
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9
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Staiger JF, Petersen CCH. Neuronal Circuits in Barrel Cortex for Whisker Sensory Perception. Physiol Rev 2020; 101:353-415. [PMID: 32816652 DOI: 10.1152/physrev.00019.2019] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The array of whiskers on the snout provides rodents with tactile sensory information relating to the size, shape and texture of objects in their immediate environment. Rodents can use their whiskers to detect stimuli, distinguish textures, locate objects and navigate. Important aspects of whisker sensation are thought to result from neuronal computations in the whisker somatosensory cortex (wS1). Each whisker is individually represented in the somatotopic map of wS1 by an anatomical unit named a 'barrel' (hence also called barrel cortex). This allows precise investigation of sensory processing in the context of a well-defined map. Here, we first review the signaling pathways from the whiskers to wS1, and then discuss current understanding of the various types of excitatory and inhibitory neurons present within wS1. Different classes of cells can be defined according to anatomical, electrophysiological and molecular features. The synaptic connectivity of neurons within local wS1 microcircuits, as well as their long-range interactions and the impact of neuromodulators, are beginning to be understood. Recent technological progress has allowed cell-type-specific connectivity to be related to cell-type-specific activity during whisker-related behaviors. An important goal for future research is to obtain a causal and mechanistic understanding of how selected aspects of tactile sensory information are processed by specific types of neurons in the synaptically connected neuronal networks of wS1 and signaled to downstream brain areas, thus contributing to sensory-guided decision-making.
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Affiliation(s)
- Jochen F Staiger
- University Medical Center Göttingen, Institute for Neuroanatomy, Göttingen, Germany; and Laboratory of Sensory Processing, Faculty of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Carl C H Petersen
- University Medical Center Göttingen, Institute for Neuroanatomy, Göttingen, Germany; and Laboratory of Sensory Processing, Faculty of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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10
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El-Boustani S, Sermet BS, Foustoukos G, Oram TB, Yizhar O, Petersen CCH. Anatomically and functionally distinct thalamocortical inputs to primary and secondary mouse whisker somatosensory cortices. Nat Commun 2020; 11:3342. [PMID: 32620835 PMCID: PMC7335197 DOI: 10.1038/s41467-020-17087-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 06/11/2020] [Indexed: 02/07/2023] Open
Abstract
Subdivisions of mouse whisker somatosensory thalamus project to cortex in a region-specific and layer-specific manner. However, a clear anatomical dissection of these pathways and their functional properties during whisker sensation is lacking. Here, we use anterograde trans-synaptic viral vectors to identify three specific thalamic subpopulations based on their connectivity with brainstem. The principal trigeminal nucleus innervates ventral posterior medial thalamus, which conveys whisker-selective tactile information to layer 4 primary somatosensory cortex that is highly sensitive to self-initiated movements. The spinal trigeminal nucleus innervates a rostral part of the posterior medial (POm) thalamus, signaling whisker-selective sensory information, as well as decision-related information during a goal-directed behavior, to layer 4 secondary somatosensory cortex. A caudal part of the POm, which apparently does not receive brainstem input, innervates layer 1 and 5A, responding with little whisker selectivity, but showing decision-related modulation. Our results suggest the existence of complementary segregated information streams to somatosensory cortices.
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Affiliation(s)
- Sami El-Boustani
- Laboratory of Sensory Processing, Brain Mind Institute, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), EPFL-SV-BMI-LSENS Station 19, CH-1015, Lausanne, Switzerland. .,Department of Basic Neurosciences, Faculty of Medicine, University of Geneva, 1 Rue Michel-Servet, 1206, Geneva, Switzerland.
| | - B Semihcan Sermet
- Laboratory of Sensory Processing, Brain Mind Institute, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), EPFL-SV-BMI-LSENS Station 19, CH-1015, Lausanne, Switzerland
| | - Georgios Foustoukos
- Laboratory of Sensory Processing, Brain Mind Institute, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), EPFL-SV-BMI-LSENS Station 19, CH-1015, Lausanne, Switzerland
| | - Tess B Oram
- Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street POB 26, 7610001, Rehovot, Israel
| | - Ofer Yizhar
- Department of Neurobiology, Weizmann Institute of Science, 234 Herzl Street POB 26, 7610001, Rehovot, Israel
| | - Carl C H Petersen
- Laboratory of Sensory Processing, Brain Mind Institute, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), EPFL-SV-BMI-LSENS Station 19, CH-1015, Lausanne, Switzerland.
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11
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Yang D, Ding C, Qi G, Feldmeyer D. Cholinergic and Adenosinergic Modulation of Synaptic Release. Neuroscience 2020; 456:114-130. [PMID: 32540364 DOI: 10.1016/j.neuroscience.2020.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/29/2020] [Accepted: 06/01/2020] [Indexed: 01/14/2023]
Abstract
In this review we will discuss the effect of two neuromodulatory transmitters, acetylcholine (ACh) and adenosine, on the synaptic release probability and short-term synaptic plasticity. ACh and adenosine differ fundamentally in the way they are released into the extracellular space. ACh is released mostly from synaptic terminals and axonal bouton of cholinergic neurons in the basal forebrain (BF). Its mode of action on synaptic release probability is complex because it activate both ligand-gated ion channels, so-called nicotinic ACh receptors and G-protein coupled muscarinic ACh receptors. In contrast, adenosine is released from both neurons and glia via nucleoside transporters or diffusion over the cell membrane in a non-vesicular, non-synaptic fashion; its receptors are exclusively G-protein coupled receptors. We show that ACh and adenosine effects are highly specific for an identified synaptic connection and depend mostly on the presynaptic but also on the postsynaptic receptor type and discuss the functional implications of these differences.
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Affiliation(s)
- Danqing Yang
- Research Centre Juelich, Institute of Neuroscience and Medicine 10, Leo-Brandt-Strasse, Juelich, Germany
| | - Chao Ding
- Research Centre Juelich, Institute of Neuroscience and Medicine 10, Leo-Brandt-Strasse, Juelich, Germany
| | - Guanxiao Qi
- Research Centre Juelich, Institute of Neuroscience and Medicine 10, Leo-Brandt-Strasse, Juelich, Germany
| | - Dirk Feldmeyer
- Research Centre Juelich, Institute of Neuroscience and Medicine 10, Leo-Brandt-Strasse, Juelich, Germany; RWTH Aachen University Hospital, Pauwelsstrasse 30, Aachen, Germany; Jülich-Aachen Research Alliance Brain - JARA Brain, Germany.
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12
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Reimann HM, Niendorf T. The (Un)Conscious Mouse as a Model for Human Brain Functions: Key Principles of Anesthesia and Their Impact on Translational Neuroimaging. Front Syst Neurosci 2020; 14:8. [PMID: 32508601 PMCID: PMC7248373 DOI: 10.3389/fnsys.2020.00008] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 01/27/2020] [Indexed: 12/11/2022] Open
Abstract
In recent years, technical and procedural advances have brought functional magnetic resonance imaging (fMRI) to the field of murine neuroscience. Due to its unique capacity to measure functional activity non-invasively, across the entire brain, fMRI allows for the direct comparison of large-scale murine and human brain functions. This opens an avenue for bidirectional translational strategies to address fundamental questions ranging from neurological disorders to the nature of consciousness. The key challenges of murine fMRI are: (1) to generate and maintain functional brain states that approximate those of calm and relaxed human volunteers, while (2) preserving neurovascular coupling and physiological baseline conditions. Low-dose anesthetic protocols are commonly applied in murine functional brain studies to prevent stress and facilitate a calm and relaxed condition among animals. Yet, current mono-anesthesia has been shown to impair neural transmission and hemodynamic integrity. By linking the current state of murine electrophysiology, Ca2+ imaging and fMRI of anesthetic effects to findings from human studies, this systematic review proposes general principles to design, apply and monitor anesthetic protocols in a more sophisticated way. The further development of balanced multimodal anesthesia, combining two or more drugs with complementary modes of action helps to shape and maintain specific brain states and relevant aspects of murine physiology. Functional connectivity and its dynamic repertoire as assessed by fMRI can be used to make inferences about cortical states and provide additional information about whole-brain functional dynamics. Based on this, a simple and comprehensive functional neurosignature pattern can be determined for use in defining brain states and anesthetic depth in rest and in response to stimuli. Such a signature can be evaluated and shared between labs to indicate the brain state of a mouse during experiments, an important step toward translating findings across species.
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Affiliation(s)
- Henning M. Reimann
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Helmholtz Association of German Research Centers (HZ), Berlin, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Helmholtz Association of German Research Centers (HZ), Berlin, Germany
- Experimental and Clinical Research Center, A Joint Cooperation Between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Berlin, Germany
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13
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Audette NJ, Bernhard SM, Ray A, Stewart LT, Barth AL. Rapid Plasticity of Higher-Order Thalamocortical Inputs during Sensory Learning. Neuron 2019; 103:277-291.e4. [PMID: 31151774 PMCID: PMC10038228 DOI: 10.1016/j.neuron.2019.04.037] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 02/11/2019] [Accepted: 04/25/2019] [Indexed: 11/16/2022]
Abstract
Neocortical circuits are sensitive to experience, showing both anatomical and electrophysiological changes in response to altered sensory input. We examined input- and cell-type-specific changes in thalamo- and intracortical pathways during learning using an automated, home-cage sensory association training (SAT) paradigm coupling multi-whisker stimulation to a water reward. We found that the posterior medial nucleus (POm) but not the ventral posterior medial (VPM) nucleus of the thalamus drives increased cortical activity after 24 h of SAT, when behavioral evidence of learning first emerges. Synaptic strengthening within the POm thalamocortical pathway was first observed at thalamic inputs to L5 and was not generated by sensory stimulation alone. Synaptic changes in L2 were delayed relative to L5, requiring 48 h of SAT to drive synaptic plasticity at thalamic and intracortical inputs onto L2 Pyr neurons. These data identify the POm thalamocortical circuit as a site of rapid synaptic plasticity during learning and suggest a temporal sequence to learning-evoked synaptic changes in the sensory cortex.
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Affiliation(s)
- Nicholas J Audette
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Sarah M Bernhard
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Ajit Ray
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Luke T Stewart
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Alison L Barth
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
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14
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Zhang W, Bruno RM. High-order thalamic inputs to primary somatosensory cortex are stronger and longer lasting than cortical inputs. eLife 2019; 8:44158. [PMID: 30741160 PMCID: PMC6370338 DOI: 10.7554/elife.44158] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 01/28/2019] [Indexed: 11/15/2022] Open
Abstract
Layer (L) 2/3 pyramidal neurons in the primary somatosensory cortex (S1) are sparsely active, spontaneously and during sensory stimulation. Long-range inputs from higher areas may gate L2/3 activity. We investigated their in vivo impact by expressing channelrhodopsin in three main sources of feedback to rat S1: primary motor cortex, secondary somatosensory cortex, and secondary somatosensory thalamic nucleus (the posterior medial nucleus, POm). Inputs from cortical areas were relatively weak. POm, however, more robustly depolarized L2/3 cells and, when paired with peripheral stimulation, evoked action potentials. POm triggered not only a stronger fast-onset depolarization but also a delayed all-or-none persistent depolarization, lasting up to 1 s and exhibiting alpha/beta-range oscillations. Inactivating POm somata abolished persistent but not initial depolarization, indicating a recurrent circuit mechanism. We conclude that secondary thalamus can enhance L2/3 responsiveness over long periods. Such timescales could provide a potential modality-specific substrate for attention, working memory, and plasticity.
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Affiliation(s)
- Wanying Zhang
- Department of Neuroscience, Columbia University, New York, United States
| | - Randy M Bruno
- Department of Neuroscience, Columbia University, New York, United States.,Kavli Institute for Brain Science, Columbia University, New York, United States.,Zuckerman Mind Brain Behavior Institute, Columbia University, New York, United States
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15
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Mo C, Sherman SM. A Sensorimotor Pathway via Higher-Order Thalamus. J Neurosci 2019; 39:692-704. [PMID: 30504278 PMCID: PMC6343647 DOI: 10.1523/jneurosci.1467-18.2018] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 11/02/2018] [Accepted: 11/24/2018] [Indexed: 11/21/2022] Open
Abstract
We now know that sensory processing in cortex occurs not only via direct communication between primary to secondary areas, but also via their parallel cortico-thalamo-cortical (i.e., trans-thalamic) pathways. Both corticocortical and trans-thalamic pathways mainly signal through glutamatergic class 1 (driver) synapses, which have robust and efficient synaptic dynamics suited for the transfer of information such as receptive field properties, suggesting the importance of class 1 synapses in feedforward, hierarchical processing. However, such a parallel arrangement has only been identified in sensory cortical areas: visual, somatosensory, and auditory. To test the generality of trans-thalamic pathways, we sought to establish its presence beyond purely sensory cortices to determine whether there is a trans-thalamic pathway parallel to the established primary somatosensory (S1) to primary motor (M1) pathway. We used trans-synaptic viral tracing, optogenetics in slice preparations, and bouton size analysis in the mouse (both sexes) to document that a circuit exists from layer 5 of S1 through the posterior medial nucleus of the thalamus to M1 with glutamatergic class 1 properties. This represents a hitherto unknown, robust sensorimotor linkage and suggests that the arrangement of parallel direct and trans-thalamic corticocortical circuits may be present as a general feature of cortical functioning.SIGNIFICANCE STATEMENT During sensory processing, feedforward pathways carry information such as receptive field properties via glutamatergic class 1 synapses, which have robust and efficient synaptic dynamics. As expected, class 1 synapses subserve the feedforward projection from primary to secondary sensory cortex, but also a route through specific higher-order thalamic nuclei, creating a parallel feedforward trans-thalamic pathway. We now extend the concept of cortical areas being connected via parallel, direct, and trans-thalamic circuits from purely sensory cortices to a sensorimotor cortical circuit (i.e., primary sensory cortex to primary motor cortex). This suggests a generalized arrangement for corticocortical communication.
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Affiliation(s)
- Christina Mo
- Department of Neurobiology, University of Chicago, Chicago, Illinois 60637
| | - S Murray Sherman
- Department of Neurobiology, University of Chicago, Chicago, Illinois 60637
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16
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Azarfar A, Calcini N, Huang C, Zeldenrust F, Celikel T. Neural coding: A single neuron's perspective. Neurosci Biobehav Rev 2018; 94:238-247. [PMID: 30227142 DOI: 10.1016/j.neubiorev.2018.09.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 08/27/2018] [Accepted: 09/07/2018] [Indexed: 12/15/2022]
Abstract
What any sensory neuron knows about the world is one of the cardinal questions in Neuroscience. Information from the sensory periphery travels across synaptically coupled neurons as each neuron encodes information by varying the rate and timing of its action potentials (spikes). Spatiotemporally correlated changes in this spiking regimen across neuronal populations are the neural basis of sensory representations. In the somatosensory cortex, however, spiking of individual (or pairs of) cortical neurons is only minimally informative about the world. Recent studies showed that one solution neurons implement to counteract this information loss is adapting their rate of information transfer to the ongoing synaptic activity by changing the membrane potential at which spike is generated. Here we first introduce the principles of information flow from the sensory periphery to the primary sensory cortex in a model sensory (whisker) system, and subsequently discuss how the adaptive spike threshold gates the intracellular information transfer from the somatic post-synaptic potential to action potentials, controlling the information content of communication across somatosensory cortical neurons.
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Affiliation(s)
- Alireza Azarfar
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour Radboud University, the Netherlands
| | - Niccoló Calcini
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour Radboud University, the Netherlands
| | - Chao Huang
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour Radboud University, the Netherlands
| | - Fleur Zeldenrust
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour Radboud University, the Netherlands
| | - Tansu Celikel
- Department of Neurophysiology, Donders Institute for Brain, Cognition, and Behaviour Radboud University, the Netherlands.
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17
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Park A, Uddin O, Li Y, Masri R, Keller A. Pain After Spinal Cord Injury Is Associated With Abnormal Presynaptic Inhibition in the Posterior Nucleus of the Thalamus. THE JOURNAL OF PAIN 2018; 19:727.e1-727.e15. [PMID: 29481977 DOI: 10.1016/j.jpain.2018.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 01/29/2018] [Accepted: 02/12/2018] [Indexed: 01/21/2023]
Abstract
Pain after spinal cord injury (SCI-Pain) is one of the most debilitating sequelae of spinal cord injury, characterized as relentless, excruciating pain that is largely refractory to treatments. Although it is generally agreed that SCI-Pain results from maladaptive plasticity in the pain processing pathway that includes the spinothalamic tract and somatosensory thalamus, the specific mechanisms underlying the development and maintenance of such pain are yet unclear. However, accumulating evidence suggests that SCI-Pain may be causally related to abnormal thalamic disinhibition, leading to hyperactivity in the posterior thalamic nucleus (PO), a higher-order nucleus involved in somatosensory and pain processing. We previously described several presynaptic mechanisms by which activity in PO is regulated, including the regulation of GABAergic as well as glutamatergic release by presynaptic metabotropic gamma-aminobutyric acid (GABAB) receptors. Using acute slices from a mouse model of SCI-Pain, we tested whether such mechanisms are affected by SCI-Pain. We reveal 2 abnormal changes in presynaptic signaling in the SCI-Pain condition. The substantial tonic activation of presynaptic GABAB receptors on GABAergic projections to PO-characteristic of normal animals-was absent in mice with SCI-Pain. Also absent in mice with SCI-Pain was the normal presynaptic regulation of glutamatergic projections to the PO by GABAB receptors. The loss of these regulatory presynaptic mechanisms in SCI-Pain may be an element of maladaptive plasticity leading to PO hyperexcitability and behavioral pain, and may suggest targets for development of novel treatments. PERSPECTIVE This report presents synaptic mechanisms that may underlie the development and maintenance of SCI-Pain. Because of the difficulty in treating SCI-Pain, a better understanding of the underlying neurobiological mechanisms is critical, and may allow development of better treatment modalities.
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Affiliation(s)
- Anthony Park
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Olivia Uddin
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Ying Li
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Radi Masri
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; Department of Endodontics, Periodontics and Prosthodontics, University of Maryland Baltimore, School of Dentistry, Baltimore, Maryland
| | - Asaf Keller
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland.
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18
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Park A, Li Y, Masri R, Keller A. Presynaptic and extrasynaptic regulation of posterior nucleus of thalamus. J Neurophysiol 2017; 118:507-519. [PMID: 28331010 DOI: 10.1152/jn.00862.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/21/2017] [Accepted: 03/16/2017] [Indexed: 11/22/2022] Open
Abstract
The posterior nucleus of thalamus (PO) is a higher-order nucleus involved in sensorimotor processing, including nociception. An important characteristic of PO is its wide range of activity profiles that vary across states of arousal, thought to underlie differences in somatosensory perception subject to attention and degree of consciousness. Furthermore, PO loses the ability to downregulate its activity level in some forms of chronic pain, suggesting that regulatory mechanisms underlying the normal modulation of PO activity may be pathologically altered. However, the mechanisms responsible for regulating such a wide dynamic range of activity are unknown. Here, we test a series of hypotheses regarding the function of several presynaptic receptors on both GABAergic and glutamatergic afferents targeting PO in mouse, using acute slice electrophysiology. We found that presynaptic GABAB receptors are present on both GABAergic and glutamatergic terminals in PO, but only those on GABAergic terminals are tonically active. We also found that release from GABAergic terminals, but not glutamatergic terminals, is suppressed by cholinergic activation and that a subpopulation of GABAergic terminals is regulated by cannabinoids. Finally, we discovered the presence of tonic currents mediated by extrasynaptic GABAA receptors in PO that are heterogeneously distributed across the nucleus. Thus we demonstrate that multiple regulatory mechanisms concurrently exist in PO, and we propose that regulation of inhibition, rather than excitation, is the more consequential mechanism by which PO activity can be regulated.NEW & NOTEWORTHY The posterior nucleus of thalamus (PO) is a key sensorimotor structure, whose activity is tightly regulated by inhibition from several nuclei. Maladaptive plasticity in this inhibition leads to severe pathologies, including chronic pain. We reveal here, for the first time in PO, multiple regulatory mechanisms that modulate synaptic transmission within PO. These findings may lead to targeted therapies for chronic pain and other disorders.
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Affiliation(s)
- Anthony Park
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Ying Li
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Radi Masri
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and.,Department of Endodontics, Periodontics and Prosthodontics, University of Maryland Baltimore, School of Dentistry, Baltimore, Maryland
| | - Asaf Keller
- Program in Neuroscience and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
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19
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Halassa MM, Acsády L. Thalamic Inhibition: Diverse Sources, Diverse Scales. Trends Neurosci 2016; 39:680-693. [PMID: 27589879 DOI: 10.1016/j.tins.2016.08.001] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 07/31/2016] [Accepted: 08/02/2016] [Indexed: 12/11/2022]
Abstract
The thalamus is the major source of cortical inputs shaping sensation, action, and cognition. Thalamic circuits are targeted by two major inhibitory systems: the thalamic reticular nucleus (TRN) and extrathalamic inhibitory (ETI) inputs. A unifying framework of how these systems operate is currently lacking. Here, we propose that TRN circuits are specialized to exert thalamic control at different spatiotemporal scales. Local inhibition of thalamic spike rates prevails during attentional selection, whereas global inhibition more likely prevails during sleep. In contrast, the ETI (arising from basal ganglia, zona incerta (ZI), anterior pretectum, and pontine reticular formation) provides temporally precise and focal inhibition, impacting spike timing. Together, these inhibitory systems allow graded control of thalamic output, enabling thalamocortical operations to dynamically match ongoing behavioral demands.
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Affiliation(s)
- Michael M Halassa
- New York University Neuroscience Institute and the Departments of Psychiatry, Neuroscience and Physiology, New York University Langone Medical Center, New York, 10016, USA; Center for Neural Science, New York University, New York, 10016, USA.
| | - László Acsády
- Laboratory of Thalamus Research, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1083 Hungary.
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20
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Sobolewski A, Kublik E, Swiejkowski DA, Kamiński J, Wróbel A. Alertness opens the effective flow of sensory information through rat thalamic posterior nucleus. Eur J Neurosci 2015; 41:1321-31. [DOI: 10.1111/ejn.12901] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 03/18/2015] [Indexed: 02/03/2023]
Affiliation(s)
- Aleksander Sobolewski
- Department of Neurophysiology; Nencki Institute of Experimental Biology; 3 Pasteur Str. Warsaw 02-093 Poland
| | - Ewa Kublik
- Department of Neurophysiology; Nencki Institute of Experimental Biology; 3 Pasteur Str. Warsaw 02-093 Poland
| | - Daniel A. Swiejkowski
- Department of Neurophysiology; Nencki Institute of Experimental Biology; 3 Pasteur Str. Warsaw 02-093 Poland
| | - Jan Kamiński
- Department of Neurophysiology; Nencki Institute of Experimental Biology; 3 Pasteur Str. Warsaw 02-093 Poland
| | - Andrzej Wróbel
- Department of Neurophysiology; Nencki Institute of Experimental Biology; 3 Pasteur Str. Warsaw 02-093 Poland
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21
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Park A, Hoffman K, Keller A. Roles of GABAA and GABAB receptors in regulating thalamic activity by the zona incerta: a computational study. J Neurophysiol 2014; 112:2580-96. [PMID: 25143541 DOI: 10.1152/jn.00282.2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The posterior thalamic nucleus (PO) is a higher order nucleus heavily implicated in the processing of somatosensory information. We have previously shown in rodent models that activity in PO is tightly regulated by inhibitory inputs from a GABAergic nucleus known as the zona incerta (ZI). The level of incertal inhibition varies under both physiological and pathological conditions, leading to concomitant changes in PO activity. These changes are causally linked to variety of phenomena from altered sensory perception to pathological pain. ZI regulation of PO is mediated by GABAA and GABAB receptors (GABAAR and GABABR) that differ in their binding kinetics and their electrophysiological properties, suggesting that each may have distinct roles in incerto-thalamic regulation. We developed a computational model to test this hypothesis. We created a two-cell Hodgkin-Huxley model representing PO and ZI with kinetically realistic GABAAR- and GABABR-mediated synapses. We simulated spontaneous and evoked firing in PO and observed how these activities were affected by inhibition mediated by each receptor type. Our model predicts that spontaneous PO activity is preferentially regulated by GABABR-mediated mechanisms, while evoked activity is preferentially regulated by GABAAR. Our model also predicts that modulation of ZI firing rate and synaptic GABA concentrations is an effective means to regulate the incerto-thalamic circuit. The coupling of distinct functions to GABAAR and GABABR presents an opportunity for the development of therapeutics, as particular aspects of incerto-thalamic regulation can be targeted by manipulating the corresponding receptor class. Thus these findings may provide interventions for pathologies of sensory processing.
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Affiliation(s)
- Anthony Park
- Program in Neuroscience, Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Kathleen Hoffman
- Department of Mathematics and Statistics, University of Maryland Baltimore County, Baltimore, Maryland
| | - Asaf Keller
- Program in Neuroscience, Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
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22
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Correlated activation of the thalamocortical network in a simple learning paradigm. Behav Brain Res 2013; 252:293-301. [PMID: 23791933 DOI: 10.1016/j.bbr.2013.06.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 06/14/2013] [Accepted: 06/16/2013] [Indexed: 11/27/2022]
Abstract
The thalamocortical loop is a key player in sensory processing. We examined the functional interactions among its elements, expressed as cross-correlations between metabolic activity of the barrel cortex, somatosensory thalamic nuclei and posterior parietal cortex, in classical conditioning. In the training stimulation of vibrissae in mice was paired with a tail shock. [14C]-2-Deoxyglucose brain mapping was performed during the first and the final sessions of conditioning (conditioned stimulus+unconditioned stimulus; CS+UCS), in groups that received only the stimulation of vibrissae (conditioned stimulus; CS-only) and in nonstimulated controls (NS). In the CS-only group, the CS evoked the correlated activity of the examined structures during the first session, but in the third session these structures did not act in a correlated manner. Conversely, in the CS+UCS condition correlations among the thalamocortical loop structures activities became stronger during the course of the training. Particularly, the posterior parietal cortex, which controls voluntary deployment of attention, together with the barrel cortex becomes involved in the network of structures with the correlated activity. The results suggest a predominant role for bottom-up processing in the somatosensory pathway at the beginning of conditioning followed by top-down processing. This is consistent with the idea that the thalamocortical loop plays a crucial role in attentional processes.
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23
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Cha M, Ji Y, Masri R. Motor cortex stimulation activates the incertothalamic pathway in an animal model of spinal cord injury. THE JOURNAL OF PAIN 2013; 14:260-9. [PMID: 23332495 DOI: 10.1016/j.jpain.2012.11.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 10/19/2012] [Accepted: 11/15/2012] [Indexed: 12/01/2022]
Abstract
UNLABELLED We have shown previously that electrical stimulation of the motor cortex reduces spontaneous painlike behaviors in animals with spinal cord injury (SCI). Because SCI pain behaviors are associated with abnormal inhibition in the inhibitory nucleus zona incerta (ZI) and because inactivation of the ZI blocks motor cortex stimulation (MCS) effects, we hypothesized that the antinociceptive effects of MCS are due to enhanced inhibitory inputs from ZI to the posterior thalamus (Po)-an area heavily implicated in nociceptive processing. To test this hypothesis, we used a rodent model of SCI pain and performed in vivo extracellular electrophysiological recordings in single well-isolated neurons in anesthetized rats. We recorded spontaneous activity in ZI and Po from 48 rats before, during, and after MCS (50 μA, 50 Hz; 300-ms pulses). We found that MCS enhanced spontaneous activity in 35% of ZI neurons and suppressed spontaneous activity in 58% of Po neurons. The majority of MCS-enhanced ZI neurons (81%) were located in the ventrorateral subdivision of ZI-the area containing Po-projecting ZI neurons. In addition, we found that inactivation of ZI using muscimol (GABAA receptor agonist) blocked the effects of MCS in 73% of Po neurons. Although we cannot eliminate the possibility that muscimol spread to areas adjacent to ZI, these findings support our hypothesis and suggest that MCS produces antinociception by activating the incertothalamic pathway. PERSPECTIVE This article describes a novel brain circuit that can be manipulated, in rats, to produce antinociception. These results have the potential to significantly impact the standard of care currently in place for the treatment of patients with intractable pain.
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Affiliation(s)
- Myeounghoon Cha
- Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Baltimore, School of Dentistry, Baltimore, Maryland 21201, USA
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24
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Bosman LWJ, Houweling AR, Owens CB, Tanke N, Shevchouk OT, Rahmati N, Teunissen WHT, Ju C, Gong W, Koekkoek SKE, De Zeeuw CI. Anatomical pathways involved in generating and sensing rhythmic whisker movements. Front Integr Neurosci 2011; 5:53. [PMID: 22065951 PMCID: PMC3207327 DOI: 10.3389/fnint.2011.00053] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 08/26/2011] [Indexed: 11/29/2022] Open
Abstract
The rodent whisker system is widely used as a model system for investigating sensorimotor integration, neural mechanisms of complex cognitive tasks, neural development, and robotics. The whisker pathways to the barrel cortex have received considerable attention. However, many subcortical structures are paramount to the whisker system. They contribute to important processes, like filtering out salient features, integration with other senses, and adaptation of the whisker system to the general behavioral state of the animal. We present here an overview of the brain regions and their connections involved in the whisker system. We do not only describe the anatomy and functional roles of the cerebral cortex, but also those of subcortical structures like the striatum, superior colliculus, cerebellum, pontomedullary reticular formation, zona incerta, and anterior pretectal nucleus as well as those of level setting systems like the cholinergic, histaminergic, serotonergic, and noradrenergic pathways. We conclude by discussing how these brain regions may affect each other and how they together may control the precise timing of whisker movements and coordinate whisker perception.
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Affiliation(s)
- Laurens W. J. Bosman
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
- Netherlands Institute for Neuroscience, Royal Academy of Arts and SciencesAmsterdam, Netherlands
| | | | - Cullen B. Owens
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
| | - Nouk Tanke
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
| | | | - Negah Rahmati
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
| | | | - Chiheng Ju
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
| | - Wei Gong
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
| | | | - Chris I. De Zeeuw
- Department of Neuroscience, Erasmus MCRotterdam, Netherlands
- Netherlands Institute for Neuroscience, Royal Academy of Arts and SciencesAmsterdam, Netherlands
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25
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Weiss C, Disterhoft JF. Exploring prefrontal cortical memory mechanisms with eyeblink conditioning. Behav Neurosci 2011; 125:318-26. [PMID: 21517143 DOI: 10.1037/a0023520] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Several studies in nonhuman primates have shown that neurons in the dorsolateral prefrontal cortex have activity that persists throughout the delay period in delayed matching to sample tasks, and age-related changes in the microcolumnar organization of the prefrontal cortex are significantly correlated with age-related declines in cognition. Activity that persists beyond the presentation of a stimulus could mediate working memory processes, and disruption of those processes could account for memory deficits that often accompany the aging process. These potential memory and aging mechanisms are being systematically examined with eyeblink conditioning paradigms in nonprimate mammalian animal models including the rabbit. The trace version of the conditioning paradigm is a particularly good system to explore declarative memory since humans do not acquire trace conditioning if they are unable to become cognitively aware of the association between a conditioning tone and an airpuff to the eye. This conditioning paradigm has been used to show that the hippocampus and cerebellum interact functionally since both conditioned responses and conditioned hippocampal pyramidal neuron activity are abolished following lesions of the cerebellar nuclei and since hippocampal lesions prevent or abolish trace conditioned blinks. However, because there are no direct connections between the hippocampal formation and the cerebellum, and because the hippocampus is not necessary for trace conditioning after a period of consolidation has elapsed, we and others have been examining the prefrontal cortex for its role in forebrain-dependent trace eyeblink conditioning. This review examines some of the literature which suggests that the prefrontal cortex serves to orchestrate a neuronal network that interacts with the cerebellum to mediate adaptively timed conditioned responses.
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Affiliation(s)
- Craig Weiss
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611-3008, USA.
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26
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Sherman SM, Guillery RW. Distinct functions for direct and transthalamic corticocortical connections. J Neurophysiol 2011; 106:1068-77. [DOI: 10.1152/jn.00429.2011] [Citation(s) in RCA: 223] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Essentially all cortical areas receive thalamic inputs and send outputs to lower motor centers. Cortical areas communicate with each other by means of direct corticocortical and corticothalamocortical pathways, often organized in parallel. We distinguish these functionally, stressing that the transthalamic pathways are class 1 (formerly known as “driver”) pathways capable of transmitting information, whereas the direct pathways vary, being either class 2 (formerly known as “modulator”) or class 1. The transthalamic pathways provide a thalamic gate that can be open or closed (and otherwise more subtly modulated), and these inputs to the thalamus are generally branches of axons with motor functions. Thus the transthalamic corticocortical pathways that can be gated carry information about the cortical processing in one cortical area and also about the motor instructions currently being issued from that area and copied to other cortical areas.
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Affiliation(s)
- S. Murray Sherman
- Department of Neurobiology, The University of Chicago, Chicago, Illinois; and
| | - R. W. Guillery
- Medical Research Council Anatomical Neuropharmacology Unit, Oxford, United Kingdom
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27
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Masri R, Quiton RL, Lucas JM, Murray PD, Thompson SM, Keller A. Zona incerta: a role in central pain. J Neurophysiol 2009; 102:181-91. [PMID: 19403748 DOI: 10.1152/jn.00152.2009] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Central pain syndrome (CPS) is a debilitating condition that affects a large number of patients with a primary lesion or dysfunction in the CNS. Despite its discovery over a century ago, the pathophysiological processes underlying the development and maintenance of CPS are poorly understood. We recently demonstrated that activity in the posterior thalamus (PO) is tightly regulated by inhibitory inputs from zona incerta (ZI). Here we test the hypothesis that CPS is associated with abnormal inhibitory regulation of PO by ZI. We recorded single units from ZI and PO in animals with CPS resulting from spinal cord lesions. Consistent with our hypothesis, the spontaneous firing rate and somatosensory evoked responses of ZI neurons were lower in lesioned animals compared with sham-operated controls. In PO, neurons recorded from lesioned rats exhibited significantly higher spontaneous firing rates and greater responses to noxious and innocuous stimuli applied to the hindpaw and to the face. These changes were not associated with increased afferent drive from the spinal trigeminal nucleus or changes in the ventroposterior thalamus. Thus CPS can result from suppressed inputs from the inhibitory nucleus zona incerta to the posterior thalamus.
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Affiliation(s)
- Radi Masri
- Department of Anatomy, University of Maryland School of Medicine, 20 Penn St., Baltimore, MD 21201, USA
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Abstract
This study tested the role of the superior colliculus in generating movements of the mystacial vibrissae--whisking. First, we compared the kinematics of whisking generated by the superior colliculus with those generated by the motor cortex. We found that in anesthetized rats, microstimulation of the colliculus evoked a sustained vibrissa protraction, whereas stimulation of motor cortex produced rhythmic protractions. Movements generated by the superior colliculus are independent of motor cortex and can be evoked at lower thresholds and shorter latencies than those generated by the motor cortex. Next we tested the hypothesis that the colliculus is acting as a simple reflex loop with the neurons that drive vibrissa movement receiving sensory input evoked by vibrissa contacts. We found that most tecto-facial neurons do not receive sensory input. Not only did these neurons not spike in response to sensory stimulation, but field potential analysis revealed that subthreshold sensory inputs do not overlap spatially with tecto-facial neurons. Together these findings suggest that the superior colliculus plays a pivotal role in vibrissa movement--regulating vibrissa set point and whisk amplitude--but does not function as a simple reflex loop. With the motor cortex controlling the whisking frequency, the superior colliculus control of set point and amplitude would account for the main parameters of voluntary whisking.
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Affiliation(s)
- Marie E Hemelt
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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BEZDUDNAYA TATIANA, KELLER ASAF. Laterodorsal nucleus of the thalamus: A processor of somatosensory inputs. J Comp Neurol 2008; 507:1979-89. [PMID: 18273888 PMCID: PMC2800129 DOI: 10.1002/cne.21664] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The laterodorsal (LD) nucleus of the thalamus has been considered a "higher order" nucleus that provides inputs to limbic cortical areas. Although its functions are largely unknown, it is often considered to be involved in spatial learning and memory. Here we provide evidence that LD is part of a hitherto unknown pathway for processing somatosensory information. Juxtacellular and extracellular recordings from LD neurons reveal that they respond to vibrissa stimulation with short latency (median = 7 ms) and large magnitude responses (median = 1.2 spikes/stimulus). Most neurons (62%) had large receptive fields, responding to six and more individual vibrissae. Electrical stimulation of the trigeminal nucleus interpolaris (SpVi) evoked short latency responses (median = 3.8 ms) in vibrissa-responsive LD neurons. Labeling produced by anterograde and retrograde neuroanatomical tracers confirmed that LD neurons receive direct inputs from SpVi. Electrophysiological and neuroanatomical analyses revealed also that LD projects upon the cingulate and retrosplenial cortex, but has only sparse projections to the barrel cortex. These findings suggest that LD is part of a novel processing stream involved in spatial orientation and learning related to somatosensory cues.
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Affiliation(s)
- TATIANA BEZDUDNAYA
- Program in Neuroscience and Department of Anatomy & Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - ASAF KELLER
- Program in Neuroscience and Department of Anatomy & Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
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Rodrigo-Angulo ML, Heredero S, Rodríguez-Veiga E, Reinoso-Suárez F. GABAergic and non-GABAergic thalamic, hypothalamic and basal forebrain projections to the ventral oral pontine reticular nucleus: their implication in REM sleep modulation. Brain Res 2008; 1210:116-25. [PMID: 18407254 DOI: 10.1016/j.brainres.2008.02.095] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Revised: 02/21/2008] [Accepted: 02/26/2008] [Indexed: 12/16/2022]
Abstract
The ventral part of the oral pontine reticular nucleus (vRPO) is a demonstrated site of brainstem REM-sleep generation and maintenance. The vRPO has reciprocal connections with structures that control other states of the sleep-wakefulness cycle, many situated in the basal forebrain and the diencephalon. Some of these connections utilize the inhibitory neurotransmitter GABA. The aim of the present work is to map the local origin of the basal forebrain and diencephalon projections to the vRPO whether GABAergic or non-GABAergic. A double-labelling technique combining vRPO injections of the neuronal tracer, cholera-toxin (CTB), with GAD-immunohistochemistry, was used for this purpose in adult cats. All of the numerous CTB-positive neurons in the reticular thalamic and dorsocaudal hypothalamic nuclei were double-labelled (CTB/GAD-positive) neurons. Approximately 15%, 14% and 16% of the CTB-positive neurons in the zona incerta and the dorsal and lateral hypothalamic areas are, respectively, CTB/GAD-positive neurons. However, only some double-labelled neurons were found in other hypothalamic nuclei with abundant CTB-positive neurons, such as the paraventricular nucleus, perifornical area and H1 Forel field. In addition, CTB-positive neurons were abundant in the central amygdaline nucleus, terminal stria bed nuclei, median preoptic nucleus, medial and lateral preoptic areas, dorsomedial and ventromedial hypothalamic nuclei, posterior hypothalamic area and periventricular thalamic nucleus. The GABAergic and non-GABAergic connections described here may be the morphological pillar through which these prosencephalic structures modulate, either by inhibiting or by exciting, the vRPO REM-sleep inducing neurons during the different sleep-wakefulness cycle states.
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Masri R, Bezdudnaya T, Trageser JC, Keller A. Encoding of stimulus frequency and sensor motion in the posterior medial thalamic nucleus. J Neurophysiol 2008; 100:681-9. [PMID: 18234976 DOI: 10.1152/jn.01322.2007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In all sensory systems, information is processed along several parallel streams. In the vibrissa-to-barrel cortex system, these include the lemniscal system and the lesser-known paralemniscal system. The posterior medial nucleus (POm) is the thalamic structure associated with the latter pathway. Previous studies suggested that POm response latencies are positively correlated with stimulation frequency and negatively correlated with response duration, providing a basis for a phase locked loop-temporal decoding of stimulus frequency. We tested this hypothesis by analyzing response latencies of POm neurons, in both awake and anesthetized rats, to vibrissae deflections at frequencies between 0.3 and 11 Hz. We found no significant, systematic correlation between stimulation frequency and the latency or duration of POm responses. We obtained similar findings from recording in awake rats, in rats under different anesthetics, and in anesthetized rats in which the reticular activating system was stimulated. These findings suggest that stimulus frequency is not reliably reflected in response latency of POm neurons. We also tested the hypothesis that POm neurons respond preferentially to sensor motion, that is, they respond to whisking in air, without contacts. We recorded from awake, head-restrained rats while monitoring vibrissae movements. All POm neurons responded to passive whisker deflections, but none responded to noncontact whisking. Thus like their counterparts in the trigeminal ganglion, POm neurons may not reliably encode whisking kinematics. These observations suggest that POm neurons might not faithfully encode vibrissae inputs to provide reliable information on vibrissae movements or contacts.
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Affiliation(s)
- Radi Masri
- Program in Neuroscience, University of Maryland School of Medicine, 20 Penn St., Baltimore, MD 21201, USA
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Urbain N, Deschênes M. Motor cortex gates vibrissal responses in a thalamocortical projection pathway. Neuron 2008; 56:714-25. [PMID: 18031687 DOI: 10.1016/j.neuron.2007.10.023] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 09/12/2007] [Accepted: 10/17/2007] [Indexed: 11/28/2022]
Abstract
Higher-order thalamic nuclei receive input from both the cerebral cortex and prethalamic sensory pathways. However, at rest these nuclei appear silent due to inhibitory input from extrathalamic regions, and it has therefore remained unclear how sensory gating of these nuclei takes place. In the rodent, the ventral division of the zona incerta (ZIv) serves as a relay station within the paralemniscal thalamocortical projection pathway for whisker-driven motor activity. Most, perhaps all, ZIv neurons are GABAergic, and recent studies have shown that these cells participate in a feedforward inhibitory circuit that blocks sensory transmission in the thalamus. The present study provides evidence that the stimulation of the vibrissa motor cortex suppresses vibrissal responses in ZIv via an intra-incertal GABAergic circuit. These results provide support for the proposal that sensory transmission operates via a top-down disinhibitory mechanism that is contingent on motor activity.
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Affiliation(s)
- Nadia Urbain
- Centre de Recherche Université Laval Robert-Giffard, Québec City, Canada G1J 2G3
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Melzer P, Mineo L, Ebner FF. Optic nerve transection affects development and use-dependent plasticity in neocortex of the rat: Quantitative acetylcholinesterase imaging. Brain Res 2007; 1139:68-84. [PMID: 17280650 DOI: 10.1016/j.brainres.2006.12.080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 12/04/2006] [Accepted: 12/14/2006] [Indexed: 11/15/2022]
Abstract
We investigated the effects of neonatal optic nerve transection on cortical acetylcholinesterase (AChE) activity in hooded rats during postnatal development and following behavioral manipulation after weaning. AChE reaction product was quantified on digitized images of histochemically stained sections in layer IV of primary somatic sensory, primary visual and visual association cortex. Rats with optic nerve transection were compared to sham-operated littermates. In all cortical regions of both types of animal, AChE reaction product was increased to peak 2 weeks after birth and decreased thereafter, reaching adult levels at the end of the third postnatal week. During postnatal development, reaction product in primary visual cortex was lower in rats deprived of retinal input than in sham-operated littermates and the area delineated by reaction product was smaller. However, optic nerve transection did not modify the time course of postnatal development or statistically significantly diminish adult levels of AChE activity. Behavioral manipulations after weaning statistically significantly increased enzyme activity in sham-operated rats in all cortical areas examined. Compared with cage rearing, training in a discrimination task with food reward had a greater impact than environmental enrichment. By contrast, in the rats with optic nerve transection enrichment and training resulted in statistically significantly increased AChE activity only in lateral visual association cortex. Our findings provide evidence for intra- and supramodal influences of the neonatal removal of retinal input on neural activity- and use-dependent modifications of cortical AChE activity. The laminar distribution of the AChE reaction product suggests that the observed changes in AChE activity were mainly related to cholinergic basal forebrain afferents. These afferents may facilitate the stabilization of transient connections between the somatic sensory and the visual pathway.
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Affiliation(s)
- Peter Melzer
- Deparment of Psychology, Vanderbilt University, 301 Wilson Hall, 111 21st Ave. S., Nashville, Tennessee 37203, USA.
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Superior sensation: superior colliculus participation in rat vibrissa system. BMC Neurosci 2007; 8:12. [PMID: 17266753 PMCID: PMC1796887 DOI: 10.1186/1471-2202-8-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Accepted: 01/31/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The superior colliculus, usually considered a visuomotor structure, is anatomically positioned to perform sensorimotor transformations in other modalities. While there is evidence for its potential participation in sensorimotor loops of the rodent vibrissa system, little is known about its functional role in vibrissa sensation or movement. In anesthetized rats, we characterized extracellularly recorded responses of collicular neurons to different types of vibrissa stimuli. RESULTS Collicular neurons had large receptive fields (median = 14.5 vibrissae). Single units displayed responses with short latencies (5.6 +/- 0.2 msec, median = 5.5) and relatively large magnitudes (1.2 +/- 0.1 spikes/stimulus, median = 1.2). Individual neurons could entrain to repetitive vibrissa stimuli delivered at < or = 20 Hz, with little reduction in phase locking, even when response magnitude was decreased. Neurons responded preferentially to vibrissa deflections at particular angles, with 43% of the cells having high (> or = 5) angular selectivity indices. CONCLUSION Results are consistent with a proposed role of the colliculus in somatosensory-mediated orienting. These properties, together with the connections of the superior colliculus in sensorimotor loops, are consistent with its involvement in orienting, alerting and attentive functions related to the vibrissa system.
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Weiss C, Weible AP, Galvez R, Disterhoft JF. Forebrain-Cerebellar Interactions During Learning. CELLSCIENCE 2006; 3:200-230. [PMID: 26617664 PMCID: PMC4662573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The cerebral cortex and cerebellum are high level neural centers that must interact cooperatively to generate coordinated and efficient goal directed movements, including those necessary for a well-timed conditioned response. In this review we describe the progress made in utilizing the forebrain-dependent trace eyeblink conditioning paradigm to understand the neural substrates mediating cerebro-cerebellar interactions during learning and consolidation of conditioned responses. This review expands upon our previous hypothesis that the interaction occurs at sites that project to the pontine nuclei (Weiss & Disterhoft, 1996), by offering more details on the function of the hippocampus and prefrontal cortex during acquisition and the circuitry involved in facilitating pontine input to the cerebellum as a necessary requisite for trace eyeblink conditioning. Our discussion describes the role of the hippocampus, caudal anterior cingulate gyrus, basal ganglia, thalamus, and sensory cortex, including the benefit of utilizing the whisker barrel cortical system. We propose that permanent changes in the sensory cortex, along with input from the caudate and claustrum, and a homologue of the primate dorsolateral prefrontal cortex, serve to bridge the stimulus free trace interval and allow the cerebellum to generate a well-timed conditioned response.
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Affiliation(s)
- Craig Weiss
- Department of Physiology, Interdepartmental Neuroscience Program, Northwestern University Feinberg School of Medicine, 303 East Chicago Ave., Chicago, IL 60611-3008
| | - Aldis P Weible
- Department of Physiology, Interdepartmental Neuroscience Program, Northwestern University Feinberg School of Medicine, 303 East Chicago Ave., Chicago, IL 60611-3008
| | - Roberto Galvez
- Department of Physiology, Interdepartmental Neuroscience Program, Northwestern University Feinberg School of Medicine, 303 East Chicago Ave., Chicago, IL 60611-3008
| | - John F Disterhoft
- Department of Physiology, Interdepartmental Neuroscience Program, Northwestern University Feinberg School of Medicine, 303 East Chicago Ave., Chicago, IL 60611-3008
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Trageser JC, Burke KA, Masri R, Li Y, Sellers L, Keller A. State-dependent gating of sensory inputs by zona incerta. J Neurophysiol 2006; 96:1456-63. [PMID: 16775205 PMCID: PMC1764852 DOI: 10.1152/jn.00423.2006] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have previously shown that the GABAergic nucleus zona incerta (ZI) suppresses vibrissae-evoked responses in the posterior medial (POm) thalamus of the rodent somatosensory system. We proposed that this inhibitory incerto-thalamic pathway regulates POm responses during different behavioral states. Here we tested the hypothesis that the cholinergic reticular activating system, implicated in regulating states of arousal, modulates ZI activity. We show that stimulation of brain stem cholinergic nuclei (laterodorsal tegmental and pedunculopontine tegmental) results in suppression of spontaneous firing of ZI neurons. Iontophoretic application of the cholinergic agonist carbachol to ZI neurons suppresses both their spontaneous firing and their vibrissae-evoked responses. We also found that carbachol application to an in vitro slice preparation suppresses spontaneous firing of neurons in the ventral sector of ZI (ZIv). Finally, we demonstrate that the majority of ZIv neurons contain parvalbumin and project to POm. Based on these results, we present the state-dependent gating hypothesis, which states that differing behavioral states-regulated by the brain stem cholinergic system-modulate ZI activity, thereby regulating the response properties of higher-order nuclei such as POm.
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Affiliation(s)
| | | | | | | | | | - Asaf Keller
- Address for reprint requests and other correspondence: A. Keller, Dept. of Anatomy and Neurobiology, University of Maryland School of Medicine, 20 Penn St., Baltimore, MD 21201 (E-mail: )
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