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Parameshwarappa V, Siponen MI, Watabe I, Karkaba A, Galazyuk A, Noreña AJ. Noise-induced hearing loss alters potassium-chloride cotransporter KCC2 and GABA inhibition in the auditory centers. Sci Rep 2024; 14:10689. [PMID: 38724641 PMCID: PMC11082187 DOI: 10.1038/s41598-024-60858-1] [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: 09/26/2023] [Accepted: 04/29/2024] [Indexed: 05/12/2024] Open
Abstract
Homeostatic plasticity, the ability of neurons to maintain their averaged activity constant around a set point value, is thought to account for the central hyperactivity after hearing loss. Here, we investigated the putative role of GABAergic neurotransmission in this mechanism after a noise-induced hearing loss larger than 50 dB in high frequencies in guinea pigs. The effect of GABAergic inhibition is linked to the normal functioning of K + -Cl- co-transporter isoform 2 (KCC2) which maintains a low intracellular concentration of chloride. The expression of membrane KCC2 were investigated before and after noise trauma in the ventral and dorsal cochlear nucleus (VCN and DCN, respectively) and in the inferior colliculus (IC). Moreover, the effect of gabazine (GBZ), a GABA antagonist, was also studied on the neural activity in IC. We show that KCC2 is downregulated in VCN, DCN and IC 3 days after noise trauma, and in DCN and IC 30 days after the trauma. As expected, GBZ application in the IC of control animals resulted in an increase of spontaneous and stimulus-evoked activity. In the noise exposed animals, on the other hand, GBZ application decreased the stimulus-evoked activity in IC neurons. The functional implications of these central changes are discussed.
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Affiliation(s)
- V Parameshwarappa
- Laboratory of Cognitive Neurosciences, Centre National de la Recherche Scientifique, Aix-Marseille University, 3 Place Victor Hugo, 13003, Marseille, France
| | - M I Siponen
- Laboratory of Cognitive Neurosciences, Centre National de la Recherche Scientifique, Aix-Marseille University, 3 Place Victor Hugo, 13003, Marseille, France
| | - I Watabe
- Laboratory of Cognitive Neurosciences, Centre National de la Recherche Scientifique, Aix-Marseille University, 3 Place Victor Hugo, 13003, Marseille, France
| | - A Karkaba
- Laboratory of Cognitive Neurosciences, Centre National de la Recherche Scientifique, Aix-Marseille University, 3 Place Victor Hugo, 13003, Marseille, France
| | - A Galazyuk
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, USA
| | - A J Noreña
- Laboratory of Cognitive Neurosciences, Centre National de la Recherche Scientifique, Aix-Marseille University, 3 Place Victor Hugo, 13003, Marseille, France.
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2
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Parameshwarappa V, Norena AJ. The effects of acute and chronic noise trauma on stimulus-evoked activity across primary auditory cortex layers. J Neurophysiol 2024; 131:225-240. [PMID: 38198658 DOI: 10.1152/jn.00427.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/19/2023] [Accepted: 01/02/2024] [Indexed: 01/12/2024] Open
Abstract
Exposure to intense noise environments is a major cause of sensorineural hearing loss and auditory perception disorders, such as tinnitus and hyperacusis, which may have a central origin. The effects of noise-induced hearing loss on the auditory cortex have been documented in many studies. One limitation of these studies, however, is that the effects of noise trauma have been mostly studied at the granular layer (i.e, the main cortical recipient of thalamic input), while the cortex is a very complex structure, with six different layers each having its own pattern of connectivity and role in sensory processing. The present study aims to investigate the effects of acute and chronic noise trauma on the laminar pattern of stimulus-evoked activity in the primary auditory cortex of the anesthetized guinea pig. We show that acute and chronic noise trauma are both followed by an increase in stimulus-evoked cortical responses, mostly in the granular and supragranular layers. The cortical responses are more monotonic as a function of the intensity level after noise trauma. There was minimal change, if any, in local field potential (LFP) amplitude after acute noise trauma, while LFP amplitude was enhanced after chronic noise trauma. Finally, LFP and the current source density analysis suggest that acute but more specifically chronic noise trauma is associated with the emergence of a new sink in the supragranular layer. This result suggests that supragranular layers become a major input recipient. We discuss the possible mechanisms and functional implications of these changes.NEW & NOTEWORTHY Our study shows that cortical activity is enhanced after trauma and that the sequence of cortical column activation during stimulus-evoked response is altered, i.e. the supragranular layer becomes a major input recipient. We speculate that these large cortical changes may play a key role in the auditory hypersensitivity (hyperacusis) that can be triggered after noise trauma in human subjects.
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Affiliation(s)
- Vinay Parameshwarappa
- Centre National de la Recherche Scientifique, Aix-Marseille University, Marseille, France
| | - Arnaud J Norena
- Centre National de la Recherche Scientifique, Aix-Marseille University, Marseille, France
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3
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Pellicer-Morata V, Wang L, Curry ADJ, Tsao JW, Waters RS. Lower jaw-to-forepaw rapid and delayed reorganization in the rat forepaw barrel subfield in primary somatosensory cortex. J Comp Neurol 2023; 531:1651-1668. [PMID: 37496376 PMCID: PMC10530121 DOI: 10.1002/cne.25523] [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: 01/13/2023] [Revised: 05/24/2023] [Accepted: 06/26/2023] [Indexed: 07/28/2023]
Abstract
We used the forepaw barrel subfield (FBS), that normally receives input from the forepaw skin surface, in rat primary somatosensory cortex as a model system to study rapid and delayed lower jaw-to-forepaw cortical reorganization. Single and multi-unit recording from FBS neurons was used to examine the FBS for the presence of "new" lower jaw input following deafferentations that include forelimb amputation, brachial plexus nerve cut, and brachial plexus anesthesia. The major findings are as follows: (1) immediately following forelimb deafferentations, new input from the lower jaw becomes expressed in the anterior FBS; (2) 7-27 weeks after forelimb amputation, new input from the lower jaw is expressed in both anterior and posterior FBS; (3) evoked response latencies recorded in the deafferented FBS following electrical stimulation of the lower jaw skin surface are significantly longer in both rapid and delayed deafferents compared to control latencies for input from the forepaw to reach the FBS or for input from lower jaw to reach the LJBSF; (4) the longer latencies suggest that an additional relay site is imposed along the somatosensory pathway for lower jaw input to access the deafferented FBS. We conclude that different sources of input and different mechanisms underlie rapid and delayed reorganization in the FBS and suggest that these findings are relevant, as an initial step, for developing a rodent animal model to investigate phantom limb phenomena.
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Affiliation(s)
- Violeta Pellicer-Morata
- Department of Physiology, University of Tennessee Health
Science Center, College of Medicine, 956 Court Avenue, Memphis, TN 38163, USA
| | - Lie Wang
- Department of Anatomy and Neurobiology, University of
Tennessee Health Science Center, College of Medicine, 855 Monroe Avenue, Suite,
Memphis, TN 38163, USA
| | - Amy de Jongh Curry
- Department of Biomedical Engineering, University of
Memphis, Herff College of Engineering, 3815 Central Avenue, Memphis, TN 38152,
USA
| | - Jack W. Tsao
- Department of Neurology, New York University, Langone
School of Medicine, 550 1 Avenue, New York, NY 10016, USA
| | - Robert S. Waters
- Department of Anatomy and Neurobiology, University of
Tennessee Health Science Center, College of Medicine, 855 Monroe Avenue, Suite,
Memphis, TN 38163, USA
- Department of Biomedical Engineering, University of
Memphis, Herff College of Engineering, 3815 Central Avenue, Memphis, TN 38152,
USA
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4
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Parameshwarappa V, Siponen M, Watabe I, Karkaba A, Galazyuk A, Noreña A. Noise-Induced Hearing Loss Alters Potassium-Chloride CoTransporter KCC2 and GABA Inhibition in the auditory centers. RESEARCH SQUARE 2023:rs.3.rs-3389804. [PMID: 37886592 PMCID: PMC10602088 DOI: 10.21203/rs.3.rs-3389804/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Homeostatic plasticity, the ability of neurons to maintain their averaged activity constant around a set point value, is thought to account for the central hyperactivity after hearing loss. Here, we investigated the putative role of GABAergic neurotransmission in this mechanism after a noise-induced hearing loss larger than 50 dB in high frequencies in guinea pigs. The effect of GABAergic inhibition is linked to the normal functioning of K+-Cl- co-transporter isoform 2 (KCC2) which maintains a low intracellular concentration of chloride. The expression of membrane KCC2 were investigated before after noise trauma in the ventral and dorsal cochlear nucleus (VCN and DCN, respectively) and in the inferior colliculus (IC). Moreover, the effect of gabazine (GBZ), a GABA antagonist, was also studied on the neural activity in IC. We show that KCC2 is downregulated in VCN, DCN and IC 3 days after noise trauma, and in DCN and IC 30 days after the trauma. As expected, GBZ application in the IC of control animals resulted in an increase of spontaneous and stimulus-evoked activity. In the noise exposed animals, on the other hand, GBZ application decreased the stimulus-evoked activity in IC neurons. The functional implications of these central changes are discussed.
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Affiliation(s)
| | - Marina Siponen
- Centre National de la Recherche Scientifique, Aix- Marseille University
| | - Isabelle Watabe
- Centre National de la Recherche Scientifique, Aix- Marseille University
| | - Alaa Karkaba
- Centre National de la Recherche Scientifique, Aix- Marseille University
| | | | - Arnaud Noreña
- Centre National de la Recherche Scientifique, Aix- Marseille University
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5
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Murray CA, Shams L. Crossmodal interactions in human learning and memory. Front Hum Neurosci 2023; 17:1181760. [PMID: 37266327 PMCID: PMC10229776 DOI: 10.3389/fnhum.2023.1181760] [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: 03/07/2023] [Accepted: 05/02/2023] [Indexed: 06/03/2023] Open
Abstract
Most studies of memory and perceptual learning in humans have employed unisensory settings to simplify the study paradigm. However, in daily life we are often surrounded by complex and cluttered scenes made up of many objects and sources of sensory stimulation. Our experiences are, therefore, highly multisensory both when passively observing the world and when acting and navigating. We argue that human learning and memory systems are evolved to operate under these multisensory and dynamic conditions. The nervous system exploits the rich array of sensory inputs in this process, is sensitive to the relationship between the sensory inputs, and continuously updates sensory representations, and encodes memory traces based on the relationship between the senses. We review some recent findings that demonstrate a range of human learning and memory phenomena in which the interactions between visual and auditory modalities play an important role, and suggest possible neural mechanisms that can underlie some surprising recent findings. We outline open questions as well as directions of future research to unravel human perceptual learning and memory.
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Affiliation(s)
- Carolyn A. Murray
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Ladan Shams
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, United States
- Department of Bioengineering, Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA, United States
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6
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Yoon YS, Drew C. Effects of the intensified frequency and time ranges on consonant enhancement in bilateral cochlear implant and hearing aid users. Front Psychol 2022; 13:918914. [PMID: 36051201 PMCID: PMC9426545 DOI: 10.3389/fpsyg.2022.918914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 07/19/2022] [Indexed: 11/13/2022] Open
Abstract
A previous study demonstrated that consonant recognition improved significantly in normal hearing listeners when useful frequency and time ranges were intensified by 6 dB. The goal of this study was to determine whether bilateral cochlear implant (BCI) and bilateral hearing aid (BHA) users experienced similar enhancement on consonant recognition with these intensified spectral and temporal cues in noise. In total, 10 BCI and 10 BHA users participated in a recognition test using 14 consonants. For each consonant, we used the frequency and time ranges that are critical for its recognition (called “target frequency and time range”), identified from normal hearing listeners. Then, a signal processing tool called the articulation-index gram (AI-Gram) was utilized to add a 6 dB gain to target frequency and time ranges. Consonant recognition was monaurally and binaurally measured under two signal processing conditions, unprocessed and intensified target frequency and time ranges at +5 and +10 dB signal-to-noise ratio and in quiet conditions. We focused on three comparisons between the BCI and BHA groups: (1) AI-Gram benefits (i.e., before and after intensifying target ranges by 6 dB), (2) enhancement in binaural benefits (better performance with bilateral devices compared to the better ear alone) via the AI-Gram processing, and (3) reduction in binaural interferences (poorer performance with bilateral devices compared to the better ear alone) via the AI-Gram processing. The results showed that the mean AI-Gram benefit was significantly improved for the BCI (max 5.9%) and BHA (max 5.2%) groups. However, the mean binaural benefit was not improved after AI-Gram processing. Individual data showed wide ranges of the AI-Gram benefit (max −1 to 23%) and binaural benefit (max −7.6 to 13%) for both groups. Individual data also showed a decrease in binaural interference in both groups after AI-Gram processing. These results suggest that the frequency and time ranges, intensified by the AI-Gram processing, contribute to consonant enhancement for monaural and binaural listening and both BCI and BHA technologies. The intensified frequency and time ranges helped to reduce binaural interference but contributed less to the synergistic binaural benefit in consonant recognition for both groups.
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7
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Wesselink DB, Sanders ZB, Edmondson LR, Dempsey-Jones H, Kieliba P, Kikkert S, Themistocleous AC, Emir U, Diedrichsen J, Saal HP, Makin TR. Malleability of the cortical hand map following a finger nerve block. SCIENCE ADVANCES 2022; 8:eabk2393. [PMID: 35452294 PMCID: PMC9032959 DOI: 10.1126/sciadv.abk2393] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Electrophysiological studies in monkeys show that finger amputation triggers local remapping within the deprived primary somatosensory cortex (S1). Human neuroimaging research, however, shows persistent S1 representation of the missing hand's fingers, even decades after amputation. Here, we explore whether this apparent contradiction stems from underestimating the distributed peripheral and central representation of fingers in the hand map. Using pharmacological single-finger nerve block and 7-tesla neuroimaging, we first replicated previous accounts (electrophysiological and other) of local S1 remapping. Local blocking also triggered activity changes to nonblocked fingers across the entire hand area. Using methods exploiting interfinger representational overlap, however, we also show that the blocked finger representation remained persistent despite input loss. Computational modeling suggests that both local stability and global reorganization are driven by distributed processing underlying the topographic map, combined with homeostatic mechanisms. Our findings reveal complex interfinger representational features that play a key role in brain (re)organization, beyond (re)mapping.
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Affiliation(s)
- Daan B. Wesselink
- Institute of Cognitive Neuroscience, University College London, London, UK
- Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Corresponding author.
| | - Zeena-Britt Sanders
- Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
| | - Laura R. Edmondson
- Active Touch Laboratory, Department of Psychology, The University of Sheffield, Sheffield, UK
| | - Harriet Dempsey-Jones
- Institute of Cognitive Neuroscience, University College London, London, UK
- Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
- School of Psychology, University of Queensland, Brisbane, Australia
| | - Paulina Kieliba
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Sanne Kikkert
- Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
| | - Andreas C. Themistocleous
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Brain Function Research Group, University of the Witwatersrand, Johannesburg, South Africa
| | - Uzay Emir
- Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
| | - Jörn Diedrichsen
- Brain and Mind Institute, University of Western Ontario, London, Canada
| | - Hannes P. Saal
- Active Touch Laboratory, Department of Psychology, The University of Sheffield, Sheffield, UK
| | - Tamar R. Makin
- Institute of Cognitive Neuroscience, University College London, London, UK
- Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
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8
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Parameshwarappa V, Pezard L, Norena AJ. Changes in the spatiotemporal pattern of spontaneous activity across a cortical column after noise trauma. J Neurophysiol 2021; 127:239-254. [PMID: 34936500 DOI: 10.1152/jn.00262.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In the auditory modality, noise trauma has often been used to investigate cortical plasticity as it causes cochlear hearing loss. One limitation of these past studies, however, is that the effects of noise trauma have been mostly documented at the granular layer, which is the main cortical recipient of thalamic inputs. Importantly, the cortex is composed of six different layers each having its own pattern of connectivity and specific role in sensory processing. The present study aims at investigating the effects of acute and chronic noise trauma on the laminar pattern of spontaneous activity in primary auditory cortex of the anesthetized guinea pig. We show that spontaneous activity is dramatically altered across cortical layers after acute and chronic noise-induced hearing loss. First, spontaneous activity was globally enhanced across cortical layers, both in terms of firing rate and amplitude of spike-triggered average of local field potentials. Second, current source density on (spontaneous) spike-triggered average of local field potentials indicates that current sinks develop in the supra- and infragranular layers. These latter results suggest that supragranular layers become a major input recipient and that the propagation of spontaneous activity over a cortical column is greatly enhanced after acute and chronic noise-induced hearing loss. We discuss the possible mechanisms and functional implications of these changes.
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Affiliation(s)
- Vinay Parameshwarappa
- Centre National de la Recherche Scientifique, Aix-Marseille University, Marseille, France
| | - Laurent Pezard
- Centre National de la Recherche Scientifique, Aix-Marseille University, Marseille, France
| | - Arnaud Jean Norena
- Centre National de la Recherche Scientifique, Aix-Marseille University, Marseille, France
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9
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Carvalho J, Renken RJ, Cornelissen FW. Predictive masking of an artificial scotoma is associated with a system-wide reconfiguration of neural populations in the human visual cortex. Neuroimage 2021; 245:118690. [PMID: 34758382 DOI: 10.1016/j.neuroimage.2021.118690] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/19/2021] [Accepted: 10/28/2021] [Indexed: 11/29/2022] Open
Abstract
The visual brain has the remarkable capacity to complete our percept of the world even when the information extracted from the visual scene is incomplete. This ability to predict missing information based on information from spatially adjacent regions is an intriguing attribute of healthy vision. Yet, it gains particular significance when it masks the perceptual consequences of a retinal lesion, leaving patients unaware of their partial loss of vision and ultimately delaying diagnosis and treatment. At present, our understanding of the neural basis of this masking process is limited which hinders both quantitative modeling as well as translational application. To overcome this, we asked the participants to view visual stimuli with and without superimposed artificial scotoma (AS). We used fMRI to record the associated cortical activity and applied model-based analyzes to track changes in cortical population receptive fields and connectivity in response to the introduction of the AS. We found that throughout the visual field and cortical hierarchy, pRFs shifted their preferred position towards the AS border. Moreover, extrastriate areas biased their sampling of V1 towards sections outside the AS projection zone, thereby effectively masking the AS with signals from spared portions of the visual field. We speculate that the signals that drive these system-wide population modifications originate in extrastriate visual areas and, through feedback, also reconfigure the neural populations in the earlier visual areas.
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Affiliation(s)
- Joana Carvalho
- Laboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Laboratory of Preclinical MRI, Champalimaud Centre for the Unknown, Avenida de Brasília, Lisbon, Portugal 1400-038.
| | - Remco J Renken
- Cognitive Neuroscience Center, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Frans W Cornelissen
- Laboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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10
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Facchini J, Rastoldo G, Xerri C, Péricat D, El Ahmadi A, Tighilet B, Zennou-Azogui Y. Unilateral vestibular neurectomy induces a remodeling of somatosensory cortical maps. Prog Neurobiol 2021; 205:102119. [PMID: 34246703 DOI: 10.1016/j.pneurobio.2021.102119] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 06/23/2021] [Accepted: 07/06/2021] [Indexed: 10/20/2022]
Abstract
Unilateral Vestibular Neurectomy (UVN) induces a postural syndrome whose compensation over time is underpinned by multimodal sensory substitution processes. However, at a chronic stage of compensation, UVN rats exhibit an enduring postural asymmetry expressed by an increase in the body weight on the ipsilesional paws. Given the anatomo-functional links between the vestibular nuclei and the primary somatosensory cortex (S1), we explored the interplay of vestibular and somatosensory cortical inputs following acute and chronic UVN. We determined whether the enduring imbalance in tactilo-plantar inputs impacts response properties of S1 cortical neurons and organizational features of somatotopic maps. We performed electrophysiological mapping of the hindpaw cutaneous representations in S1, immediately and one month after UVN. In parallel, we assessed the posturo-locomotor imbalance during the compensation process. UVN immediately induces an expansion of the cortical neuron cutaneous receptive fields (RFs) leading to a partial dedifferentiation of somatotopic maps. This effect was demonstrated for the ventral skin surface representations and was greater on the contralesional hindpaw for which the neuronal threshold to skin pressure strongly decreased. The RF enlargement was amplified for the representation of the ipsilesional hindpaw in relation to persistent postural asymmetries, but was transitory for the contralesional one. Our study shows, for the first time, that vestibular inputs exert a modulatory influence on S1 neuron's cutaneous responses. The lesion-induced cortical malleability highlights the influence of vestibular inputs on tactile processing related to postural control.
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Affiliation(s)
- Justine Facchini
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Christian Xerri
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - David Péricat
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Abdessadek El Ahmadi
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France.
| | - Yoh'i Zennou-Azogui
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France.
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11
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García-Magro N, Martin YB, Negredo P, Zafra F, Avendaño C. Microglia and Inhibitory Circuitry in the Medullary Dorsal Horn: Laminar and Time-Dependent Changes in a Trigeminal Model of Neuropathic Pain. Int J Mol Sci 2021; 22:4564. [PMID: 33925417 PMCID: PMC8123867 DOI: 10.3390/ijms22094564] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/22/2021] [Accepted: 04/22/2021] [Indexed: 02/07/2023] Open
Abstract
Craniofacial neuropathic pain affects millions of people worldwide and is often difficult to treat. Two key mechanisms underlying this condition are a loss of the negative control exerted by inhibitory interneurons and an early microglial reaction. Basic features of these mechanisms, however, are still poorly understood. Using the chronic constriction injury of the infraorbital nerve (CCI-IoN) model of neuropathic pain in mice, we have examined the changes in the expression of GAD, the synthetic enzyme of GABA, and GlyT2, the membrane transporter of glycine, as well as the microgliosis that occur at early (5 days) and late (21 days) stages post-CCI in the medullary and upper spinal dorsal horn. Our results show that CCI-IoN induces a down-regulation of GAD at both postinjury survival times, uniformly across the superficial laminae. The expression of GlyT2 showed a more discrete and heterogeneous reduction due to the basal presence in lamina III of 'patches' of higher expression, interspersed within a less immunoreactive 'matrix', which showed a more substantial reduction in the expression of GlyT2. These patches coincided with foci lacking any perceptible microglial reaction, which stood out against a more diffuse area of strong microgliosis. These findings may provide clues to better understand the neural mechanisms underlying allodynia in neuropathic pain syndromes.
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Affiliation(s)
- Nuria García-Magro
- Department of Anatomy, Histology and Neuroscience, Medical School, Autónoma University of Madrid, 28029 Madrid, Spain; (N.G.-M.); (P.N.)
- Ph.D. Programme in Neuroscience, Doctoral School, Autónoma University of Madrid, 28049 Madrid, Spain
| | - Yasmina B. Martin
- Departamento de Anatomía, Facultad de Medicina, Universidad Francisco de Vitoria, Pozuelo de Alarcón, 28223 Madrid, Spain;
| | - Pilar Negredo
- Department of Anatomy, Histology and Neuroscience, Medical School, Autónoma University of Madrid, 28029 Madrid, Spain; (N.G.-M.); (P.N.)
| | - Francisco Zafra
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049 Madrid, Spain;
| | - Carlos Avendaño
- Department of Anatomy, Histology and Neuroscience, Medical School, Autónoma University of Madrid, 28029 Madrid, Spain; (N.G.-M.); (P.N.)
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12
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Gudmundsson L, Vohryzek J, Fornari E, Clarke S, Hagmann P, Crottaz-Herbette S. A brief exposure to rightward prismatic adaptation changes resting-state network characteristics of the ventral attentional system. PLoS One 2020; 15:e0234382. [PMID: 32584824 PMCID: PMC7316264 DOI: 10.1371/journal.pone.0234382] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 05/26/2020] [Indexed: 12/02/2022] Open
Abstract
A brief session of rightward prismatic adaptation (R-PA) has been shown to alleviate neglect symptoms in patients with right hemispheric damage, very likely by switching hemispheric dominance of the ventral attentional network (VAN) from the right to the left and by changing task-related activity within the dorsal attentional network (DAN). We have investigated this very rapid change in functional organisation with a network approach by comparing resting-state connectivity before and after a brief exposure i) to R-PA (14 normal subjects; experimental condition) or ii) to plain glasses (12 normal subjects; control condition). A whole brain analysis (comprising 129 regions of interest) highlighted R-PA-induced changes within a bilateral, fronto-temporal network, which consisted of 13 nodes and 11 edges; all edges involved one of 4 frontal nodes, which were part of VAN. The analysis of network characteristics within VAN and DAN revealed a R-PA-induced decrease in connectivity strength between nodes and a decrease in local efficiency within VAN but not within DAN. These results indicate that the resting-state connectivity configuration of VAN is modulated by R-PA, possibly by decreasing its modularity.
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Affiliation(s)
- Louis Gudmundsson
- Department of Radiology, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
- Neuropsychology and Neurorehabilitation Service, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
| | - Jakub Vohryzek
- Department of Radiology, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
- Department of Psychiatry, Hedonia Research Group, University of Oxford, Oxford, United Kingdom
| | - Eleonora Fornari
- CIBM (Centre d'Imagerie Biomédicale), Dept. of Radiology, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
| | - Stephanie Clarke
- Neuropsychology and Neurorehabilitation Service, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
| | - Patric Hagmann
- Department of Radiology, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
- Signal Processing Lab 5 (LTS5), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Sonia Crottaz-Herbette
- Neuropsychology and Neurorehabilitation Service, Centre Hospitalier Universitaire Vaudois (CHUV), and University of Lausanne, Lausanne, Switzerland
- * E-mail:
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13
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Rahayu UB, Wibowo S, Setyopranoto I. The Effectiveness of Early Mobilization Time on Balance and Functional Ability after Ischemic Stroke. Open Access Maced J Med Sci 2019; 7:1088-1092. [PMID: 31049086 PMCID: PMC6490474 DOI: 10.3889/oamjms.2019.269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 04/03/2019] [Accepted: 04/04/2019] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND: Early mobilisation (EM) after-ischemic stroke is a motor learning intervention aimed to restore nerve cells and to improve balance and functional ability. Unfortunately, the study of when this intervention began has not been widely studied. AIM: On this study was compared the effect of EM started at 24 hours and 48 hours after an ischemic stroke on balance and functional ability. MATERIAL AND METHODS: Randomized controlled trial involving 40 patients on 2 groups meeting predefined inclusion criteria. The levels of balance were measured using the Berg Balance Scale, and the functional ability was measured using the Barthel Index, at 5th and 7th day. RESULTS: A significant difference was observed in both balance (p = 0.038) and functional ability (p = 0.021) obtained on the 7th day of assessment between both groups. A significant difference on the 5th day was observed only in the functional ability (p = 0.002) and not in the balance (p = 0.147), between the groups. CONCLUSION: EM started at 24 hours after the ischemic stroke has been found to have a better impact on balance and functional ability compared to that at 48 hours.
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Affiliation(s)
- Umi Budi Rahayu
- Department of Physiotherapy, Faculty of Health Science, Universitas Muhammadiyah Surakarta, Indonesia
| | - Samekto Wibowo
- Department of Neurology, Faculty of Medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Ismail Setyopranoto
- Department of Neurology, Faculty of Medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia
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14
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Kuehn E, Dinse J, Jakobsen E, Long X, Schäfer A, Bazin PL, Villringer A, Sereno MI, Margulies DS. Body Topography Parcellates Human Sensory and Motor Cortex. Cereb Cortex 2018; 27:3790-3805. [PMID: 28184419 PMCID: PMC6248394 DOI: 10.1093/cercor/bhx026] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Indexed: 12/25/2022] Open
Abstract
The cytoarchitectonic map as proposed by Brodmann currently dominates models of human sensorimotor cortical structure, function, and plasticity. According to this model, primary motor cortex, area 4, and primary somatosensory cortex, area 3b, are homogenous areas, with the major division lying between the two. Accumulating empirical and theoretical evidence, however, has begun to question the validity of the Brodmann map for various cortical areas. Here, we combined in vivo cortical myelin mapping with functional connectivity analyses and topographic mapping techniques to reassess the validity of the Brodmann map in human primary sensorimotor cortex. We provide empirical evidence that area 4 and area 3b are not homogenous, but are subdivided into distinct cortical fields, each representing a major body part (the hand and the face). Myelin reductions at the hand-face borders are cortical layer-specific, and coincide with intrinsic functional connectivity borders as defined using large-scale resting state analyses. Our data extend the Brodmann model in human sensorimotor cortex and suggest that body parts are an important organizing principle, similar to the distinction between sensory and motor processing.
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Affiliation(s)
- Esther Kuehn
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig 04103, Germany.,Department of Psychology and Language Sciences, University College London, London WC1H 0DG, UK.,Center for Behavioral Brain Sciences Magdeburg, Magdeburg 39106, Germany.,Aging and Cognition Research Group, DZNE, Magdeburg 39106, Germany
| | - Juliane Dinse
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig 04103, Germany.,Faculty of Computer Science, Otto-von-Guericke University, Magdeburg 39106, Germany
| | - Estrid Jakobsen
- Max Planck Research Group for Neuroanatomy & Connectivity, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig04103, Germany
| | - Xiangyu Long
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig04103, Germany
| | - Andreas Schäfer
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig04103, Germany
| | - Pierre-Louis Bazin
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig 04103, Germany.,Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig 04103, Germany
| | - Arno Villringer
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig04103, Germany
| | - Martin I Sereno
- Department of Psychology and Language Sciences, University College London, LondonWC1H 0DG, UK
| | - Daniel S Margulies
- Max Planck Research Group for Neuroanatomy & Connectivity, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig04103, Germany
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15
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Gannon MA, Long SM, Parks NA. Homeostatic plasticity in human extrastriate cortex following a simulated peripheral scotoma. Exp Brain Res 2017; 235:3391-3401. [PMID: 28821922 DOI: 10.1007/s00221-017-5042-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 07/20/2017] [Indexed: 12/19/2022]
Abstract
Neuroimaging and patient work over the past decade have indicated that, following retinal deafferentation, the human visual cortex undergoes a large-scale and enduring reorganization of its topography such that the classical retinotopic organization of deafferented visual cortex remaps to represent non-classical regions of visual space. Such long-term visual reorganization is proposed to occur through changes in the functional balance of deafferented visual circuits that engage more lasting changes through activity-dependent neuroplasticity. Here, we investigated the short-term changes in functional balance (short-term plasticity; homeostatic plasticity) that occur within deafferented human visual cortices. We recorded electroencephalogram (EEG) while observers were conditioned for 6 s with a simulated retinal scotoma (artificial scotoma) positioned 8.0° in the periphery. Visual evoked potentials (VEPs) evoked by the onset of sinusoidal visual probes that varied in their tilt were used to examine changes in cortical excitability within and around cortical representations of the simulated scotoma. Psychophysical orientation functions obtained from discrimination of visual probe tilt were used to examine alterations in the stimulus selectivity within the scotoma representations. Consistent with a mechanism of homeostatic disinhibition, an early extrastriate component of the VEP (the early phase P1) exhibited increased amplitude following the condition with a simulated scotoma relative to a stimulus-matched control condition. This increased visual cortical response was associated with a reduction in the slope of the psychophysical orientation function, suggesting a broader tuning of neural populations within scotoma representations. Together, these findings support a mechanism of disinhibition in promoting visual plasticity and topographical reorganization.
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Affiliation(s)
- Matthew A Gannon
- Department of Psychological Science, University of Arkansas, Fayetteville, AR, USA.
| | - Stephanie M Long
- Department of Psychological Science, University of Arkansas, Fayetteville, AR, USA
| | - Nathan A Parks
- Department of Psychological Science, University of Arkansas, Fayetteville, AR, USA
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16
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Blake DT. Network Supervision of Adult Experience and Learning Dependent Sensory Cortical Plasticity. Compr Physiol 2017. [DOI: 10.1002/cphy.c160036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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17
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Acquired hearing loss and brain plasticity. Hear Res 2017; 343:176-190. [DOI: 10.1016/j.heares.2016.05.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/29/2016] [Accepted: 05/19/2016] [Indexed: 12/19/2022]
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18
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Qu X, Yan J, Li X, Zhang P, Liu X. Topography of Synchronization of Somatosensory Evoked Potentials Elicited by Stimulation of the Sciatic Nerve in Rat. Front Comput Neurosci 2016; 10:43. [PMID: 27199728 PMCID: PMC4854893 DOI: 10.3389/fncom.2016.00043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 04/18/2016] [Indexed: 01/14/2023] Open
Abstract
Purpose: Traditionally, the topography of somatosensory evoked potentials (SEPs) is generated based on amplitude and latency. However, this operation focuses on the physical morphology and field potential-power, so it suffers from difficulties in performing identification in an objective manner. In this study, measurement of the synchronization of SEPs is proposed as a method to explore brain functional networks as well as the plasticity after peripheral nerve injury. Method: SEPs elicited by unilateral sciatic nerve stimulation in twelve adult male Sprague-Dawley (SD) rats in the normal group were compared with SEPs evoked after unilateral sciatic nerve hemisection in four peripheral nerve injured SD rats. The characterization of synchronized networks from SEPs was conducted using equal-time correlation, correlation matrix analysis, and comparison to randomized surrogate data. Eigenvalues of the correlation matrix were used to identify the clusters of functionally synchronized neuronal activity, and the participation index (PI) was calculated to indicate the involvement of each channel in the cluster. The PI value at the knee point of the PI histogram was used as a threshold to demarcate the cortical boundary. Results: Ten out of the twelve normal rats showed only one synchronized brain network. The remaining two normal rats showed one strong and one weak network. In the peripheral nerve injured group, only one synchronized brain network was found in each rat. In the normal group, all network shapes appear regular and the network is largely contained in the posterior cortex. In the injured group, the network shapes appear irregular, the network extends anteriorly and posteriorly, and the network area is significantly larger. There are considerable individual variations in the shape and location of the network after peripheral nerve injury. Conclusion: The proposed method can detect functional brain networks. Compared to the results of the traditional SEP-morphology-based analysis method, the synchronized functional network area is much larger. Furthermore, the proposed method can also characterize the rapid cortical plasticity after a peripheral nerve is acutely injured.
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Affiliation(s)
- Xuefeng Qu
- Division of the Comprehensive Epilepsy Center and Neurofunctional Monitoring Laboratory, Department of Neurology, Peking University People's Hospital Beijing, China
| | - Jiaqing Yan
- School of Electrical and Control Engineering, North China University of Technology Beijing, China
| | - Xiaoli Li
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University Beijing, China
| | - Peixun Zhang
- Department of Trauma and Orthopaedics, Peking University People's Hospital Beijing, China
| | - Xianzeng Liu
- Division of the Comprehensive Epilepsy Center and Neurofunctional Monitoring Laboratory, Department of Neurology, Peking University People's Hospital Beijing, China
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19
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Chang JL, Pross SE, Findlay AM, Mizuiri D, Henderson-Sabes J, Garrett C, Nagarajan SS, Cheung SW. Spatial plasticity of the auditory cortex in single-sided deafness. Laryngoscope 2016; 126:2785-2791. [DOI: 10.1002/lary.25961] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2016] [Indexed: 11/05/2022]
Affiliation(s)
- Jolie L. Chang
- Department of Otolaryngology-Head and Neck Surgery; University of California, San Francisco; San Francisco California U.S.A
| | - Seth E. Pross
- Department of Otolaryngology-Head and Neck Surgery; University of California, San Francisco; San Francisco California U.S.A
| | - Anne M. Findlay
- Department of Radiology and Biomedical Imaging; University of California, San Francisco; San Francisco California U.S.A
| | - Danielle Mizuiri
- Department of Radiology and Biomedical Imaging; University of California, San Francisco; San Francisco California U.S.A
| | - Jennifer Henderson-Sabes
- Department of Otolaryngology-Head and Neck Surgery; University of California, San Francisco; San Francisco California U.S.A
| | - Coleman Garrett
- Department of Radiology and Biomedical Imaging; University of California, San Francisco; San Francisco California U.S.A
| | - Srikantan S. Nagarajan
- Department of Otolaryngology-Head and Neck Surgery; University of California, San Francisco; San Francisco California U.S.A
- Department of Radiology and Biomedical Imaging; University of California, San Francisco; San Francisco California U.S.A
| | - Steven W. Cheung
- Department of Otolaryngology-Head and Neck Surgery; University of California, San Francisco; San Francisco California U.S.A
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20
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Oouchida Y, Sudo T, Inamura T, Tanaka N, Ohki Y, Izumi SI. Maladaptive change of body representation in the brain after damage to central or peripheral nervous system. Neurosci Res 2015; 104:38-43. [PMID: 26748075 DOI: 10.1016/j.neures.2015.12.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 12/24/2015] [Accepted: 12/24/2015] [Indexed: 12/12/2022]
Abstract
Our brain has great flexibility to cope with various changes in the environment. Use-dependent plasticity, a kind of functional plasticity, plays the most important role in this ability to cope. For example, the functional recovery of paretic limb motor movement during post-stroke rehabilitation depends mainly on how much it is used. Patients with hemiparesis, however, tend to gradually disuse the paretic limb because of its motor impairment. Decreased use of the paretic hand then leads to further functional decline brought by use-dependent plasticity. To break this negative loop, body representation, which is the conscious and unconscious information regarding body state stored in the brain, is key for using the paretic limb because it plays an important role in selecting an effector while a motor program is generated. In an attempt to understand body representation in the brain, we reviewed animal and human literature mainly on the alterations of the sensory maps in the primary somatosensory cortex corresponding to the changes in limb usage caused by peripheral or central nervous system damage.
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Affiliation(s)
- Yutaka Oouchida
- Department of Physical Medicine and Rehabilitation, Tohoku University, Miyagi, Japan.
| | - Tamami Sudo
- Graduate School of Biomedical Engineering, Tohoku University, Miyagi, Japan
| | - Tetsunari Inamura
- National Institute of Informatics, Tokyo, Japan; The Graduate University for Advanced Studies, Japan
| | - Naofumi Tanaka
- Department of Physical Medicine and Rehabilitation, Tohoku University, Miyagi, Japan
| | - Yukari Ohki
- School of Medicine, Kyorin University, Tokyo, Japan
| | - Shin-ichi Izumi
- Department of Physical Medicine and Rehabilitation, Tohoku University, Miyagi, Japan; Graduate School of Biomedical Engineering, Tohoku University, Miyagi, Japan
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21
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Decosta-Fortune TM, Li CX, de Jongh Curry AL, Waters RS. Differential Pattern of Interhemispheric Connections Between Homotopic Layer V Regions in the Forelimb Representation in Rat Barrel Field Cortex. Anat Rec (Hoboken) 2015; 298:1885-902. [PMID: 26332205 DOI: 10.1002/ar.23262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/12/2015] [Accepted: 04/07/2015] [Indexed: 11/05/2022]
Abstract
Layer V neurons in forelimb and shoulder representations in rat first somatosensory cortex (SI) project to the contralateral SI. However, few studies have addressed whether projections from specific subregions of the forelimb representation, namely forepaw, wrist, or forearm, terminate at homotopic sites in the contralateral SI. Neuroanatomical retrograde (cholera toxin B subunit [CT-B]) or anterograde (biodextran amine [BDA]) tracers were injected into physiologically identified sites in layer V in specific forelimb and/or shoulder representations in SI to examine the projection to contralateral SI in young adult rats (N = 17). Injection and target sites were flattened and cut in a tangential plane to relate labeling to the body map or cut along a coronal plane to relate labeling to cortical layers. Results indicate that layer V neurons project to cortical laminae II-VI in contralateral SI, with the densest labeling in layer V followed by layer III. In contrast, layer V neurons send sparse projections to layer IV. Furthermore, layer V neurons in wrist, forearm, and shoulder project to homotopic sites in contralateral layer V, while neurons in the forepaw representation project largely to sites in perigranular and dysgranular cortex adjacent to their homotopic territory. Our results provide evidence for a differential pattern of interhemispheric projections from forelimb and shoulder representations to the opposite SI and a detailed description of areal and laminar projection patterns of layer V neurons in the SI forelimb and shoulder cortices.
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Affiliation(s)
- Tina M Decosta-Fortune
- Department of Biomedical Engineering, Herff College of Engineering, University of Memphis, Memphis, Tennessee
| | - Cheng X Li
- Department of Biomedical Engineering, Herff College of Engineering, University of Memphis, Memphis, Tennessee.,Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Amy L de Jongh Curry
- Department of Biomedical Engineering, Herff College of Engineering, University of Memphis, Memphis, Tennessee
| | - Robert S Waters
- Department of Biomedical Engineering, Herff College of Engineering, University of Memphis, Memphis, Tennessee.,Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
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22
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Neural Mechanism of Corticofugal Modulation of Tuning Property in Frequency Domain of Bat’s Auditory System. Neural Process Lett 2015. [DOI: 10.1007/s11063-015-9425-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Emergence of virtual reality as a tool for upper limb rehabilitation: incorporation of motor control and motor learning principles. Phys Ther 2015; 95:415-25. [PMID: 25212522 PMCID: PMC4348716 DOI: 10.2522/ptj.20130579] [Citation(s) in RCA: 171] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The primary focus of rehabilitation for individuals with loss of upper limb movement as a result of acquired brain injury is the relearning of specific motor skills and daily tasks. This relearning is essential because the loss of upper limb movement often results in a reduced quality of life. Although rehabilitation strives to take advantage of neuroplastic processes during recovery, results of traditional approaches to upper limb rehabilitation have not entirely met this goal. In contrast, enriched training tasks, simulated with a wide range of low- to high-end virtual reality-based simulations, can be used to provide meaningful, repetitive practice together with salient feedback, thereby maximizing neuroplastic processes via motor learning and motor recovery. Such enriched virtual environments have the potential to optimize motor learning by manipulating practice conditions that explicitly engage motivational, cognitive, motor control, and sensory feedback-based learning mechanisms. The objectives of this article are to review motor control and motor learning principles, to discuss how they can be exploited by virtual reality training environments, and to provide evidence concerning current applications for upper limb motor recovery. The limitations of the current technologies with respect to their effectiveness and transfer of learning to daily life tasks also are discussed.
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24
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Eggermont JJ. Tinnitus and neural plasticity (Tonndorf lecture at XIth International Tinnitus Seminar, Berlin, 2014). Hear Res 2015; 319:1-11. [DOI: 10.1016/j.heares.2014.10.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 09/23/2014] [Accepted: 10/02/2014] [Indexed: 11/13/2022]
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25
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Interplay between intra- and interhemispheric remodeling of neural networks as a substrate of functional recovery after stroke: Adaptive versus maladaptive reorganization. Neuroscience 2014; 283:178-201. [DOI: 10.1016/j.neuroscience.2014.06.066] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 06/27/2014] [Accepted: 06/27/2014] [Indexed: 11/18/2022]
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26
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Martin YB, Negredo P, Villacorta-Atienza JA, Avendaño C. Trigeminal intersubnuclear neurons: morphometry and input-dependent structural plasticity in adult rats. J Comp Neurol 2014; 522:1597-617. [PMID: 24178892 DOI: 10.1002/cne.23494] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 10/11/2013] [Accepted: 10/15/2013] [Indexed: 11/09/2022]
Abstract
Intersubnuclear neurons in the caudal division of the spinal trigeminal nucleus that project to the principal nucleus (Pr5) play an active role in shaping the receptive fields of other neurons, at different levels in the ascending sensory system that processes information originating from the vibrissae. By using retrograde labeling and digital reconstruction, we investigated the morphometry and topology of the dendritic trees of these neurons and the changes induced by long-term experience-dependent plasticity in adult male rats. Primary afferent input was either eliminated by transection of the right infraorbital nerve (IoN), or selectively altered by repeated whisker clipping on the right side. These neurons do not display asymmetries between sides in basic metric and topologic parameters (global number of trees, nodes, spines, or dendritic ends), although neurons on the left tend to have longer terminal segments. Ipsilaterally, both deafferentation (IoN transection) and deprivation (whisker trimming) reduced the density of spines, and the former also caused a global increase in total dendritic length and a relative increase in more complex arbors. Contralaterally, deafferentation reduced more complex dendritic trees, and caused a moderate decline in dendritic length and spatial reach, and a loss of spines in number and density. Deprivation caused a similar, but more profound, effect on spines. Our findings provide original quantitative descriptions of a scarcely known cell population, and show that denervation- or deprivation-derived plasticity is expressed not only by neurons at higher levels of the sensory pathways, but also by neurons in key subcortical circuits for sensory processing.
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Affiliation(s)
- Yasmina B Martin
- Department of Anatomy, Histology, & Neuroscience, Autonoma University of Madrid, 28029, Madrid, Spain; Department of Anatomy, Francisco de Vitoria University, 28223, Pozuelo de Alarcón, Madrid, Spain
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27
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Oliveira JT, Bittencourt-Navarrete RE, de Almeida FM, Tonda-Turo C, Martinez AMB, Franca JG. Enhancement of median nerve regeneration by mesenchymal stem cells engraftment in an absorbable conduit: improvement of peripheral nerve morphology with enlargement of somatosensory cortical representation. Front Neuroanat 2014; 8:111. [PMID: 25360086 PMCID: PMC4199278 DOI: 10.3389/fnana.2014.00111] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 09/18/2014] [Indexed: 12/12/2022] Open
Abstract
We studied the morphology and the cortical representation of the median nerve (MN), 10 weeks after a transection immediately followed by treatment with tubulization using a polycaprolactone (PCL) conduit with or without bone marrow-derived mesenchymal stem cell (MSC) transplant. In order to characterize the cutaneous representation of MN inputs in primary somatosensory cortex (S1), electrophysiological cortical mapping of the somatosensory representation of the forepaw and adjacent body parts was performed after acute lesion of all brachial plexus nerves, except for the MN. This was performed in ten adult male Wistar rats randomly assigned in three groups: MN Intact (n = 4), PCL-Only (n = 3), and PCL+MSC (n = 3). Ten weeks before mapping procedures in animals from PCL-Only and PCL+MSC groups, animal were subjected to MN transection with removal of a 4-mm-long segment, immediately followed by suturing a PCL conduit to the nerve stumps with (PCL+MSC group) or without (PCL-Only group) injection of MSC into the conduit. After mapping the representation of the MN in S1, animals had a segment of the regenerated nerve processed for light and transmission electron microscopy. For histomorphometric analysis of the nerve segment, sample size was increased to five animals per experimental group. The PCL+MSC group presented a higher number of myelinated fibers and a larger cortical representation of MN inputs in S1 (3,383 ± 390 fibers; 2.3 mm2, respectively) than the PCL-Only group (2,226 ± 575 fibers; 1.6 mm2). In conclusion, MSC-based therapy associated with PCL conduits can improve MN regeneration. This treatment seems to rescue the nerve representation in S1, thus minimizing the stabilization of new representations of adjacent body parts in regions previously responsive to the MN.
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Affiliation(s)
- Julia T Oliveira
- Laboratório de Neurodegeneração e Reparo, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
| | | | - Fernanda M de Almeida
- Laboratório de Neurodegeneração e Reparo, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil ; Universidade Federal do Rio de Janeiro Macaé, Brazil
| | - Chiara Tonda-Turo
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino Torino, Italy
| | - Ana Maria B Martinez
- Laboratório de Neurodegeneração e Reparo, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil ; Departamento de Anatomia Patológica, Faculdade de Medicina, e Pós Graduação em Anatomia Patológica, Centro de Ciências da Saúde, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
| | - João G Franca
- Programa de Neurobiologia, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
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28
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The cortical distribution of multisensory neurons was modulated by multisensory experience. Neuroscience 2014; 272:1-9. [DOI: 10.1016/j.neuroscience.2014.04.068] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 04/14/2014] [Accepted: 04/28/2014] [Indexed: 11/23/2022]
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Gold JR, Bajo VM. Insult-induced adaptive plasticity of the auditory system. Front Neurosci 2014; 8:110. [PMID: 24904256 PMCID: PMC4033160 DOI: 10.3389/fnins.2014.00110] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 04/28/2014] [Indexed: 01/10/2023] Open
Abstract
The brain displays a remarkable capacity for both widespread and region-specific modifications in response to environmental challenges, with adaptive processes bringing about the reweighing of connections in neural networks putatively required for optimizing performance and behavior. As an avenue for investigation, studies centered around changes in the mammalian auditory system, extending from the brainstem to the cortex, have revealed a plethora of mechanisms that operate in the context of sensory disruption after insult, be it lesion-, noise trauma, drug-, or age-related. Of particular interest in recent work are those aspects of auditory processing which, after sensory disruption, change at multiple—if not all—levels of the auditory hierarchy. These include changes in excitatory, inhibitory and neuromodulatory networks, consistent with theories of homeostatic plasticity; functional alterations in gene expression and in protein levels; as well as broader network processing effects with cognitive and behavioral implications. Nevertheless, there abounds substantial debate regarding which of these processes may only be sequelae of the original insult, and which may, in fact, be maladaptively compelling further degradation of the organism's competence to cope with its disrupted sensory context. In this review, we aim to examine how the mammalian auditory system responds in the wake of particular insults, and to disambiguate how the changes that develop might underlie a correlated class of phantom disorders, including tinnitus and hyperacusis, which putatively are brought about through maladaptive neuroplastic disruptions to auditory networks governing the spatial and temporal processing of acoustic sensory information.
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Affiliation(s)
- Joshua R Gold
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
| | - Victoria M Bajo
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
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Cortical neuron response properties are related to lesion extent and behavioral recovery after sensory loss from spinal cord injury in monkeys. J Neurosci 2014; 34:4345-63. [PMID: 24647955 DOI: 10.1523/jneurosci.4954-13.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Lesions of the dorsal columns at a mid-cervical level render the hand representation of the contralateral primary somatosensory cortex (area 3b) unresponsive. Over weeks of recovery, most of this cortex becomes responsive to touch on the hand. Determining functional properties of neurons within the hand representation is critical to understanding the neural basis of this adaptive plasticity. Here, we recorded neural activity across the hand representation of area 3b with a 100-electrode array and compared results from owl monkeys and squirrel monkeys 5-10 weeks after lesions with controls. Even after extensive lesions, performance on reach-to-grasp tasks returned to prelesion levels, and hand touches activated territories mainly within expected cortical locations. However, some digit representations were abnormal, such that receptive fields of presumably reactivated neurons were larger and more often involved discontinuous parts of the hand compared with controls. Hand stimulation evoked similar neuronal firing rates in lesion and control monkeys. By assessing the same monkeys with multiple measures, we determined that properties of neurons in area 3b were highly correlated with both the lesion severity and the impairment of hand use. We propose that the reactivation of neurons with near-normal response properties and the recovery of near-normal somatotopy likely supported the recovery of hand use. Given the near-completeness of the more extensive dorsal column lesions we studied, we suggest that alternate spinal afferents, in addition to the few spared primary axon afferents in the dorsal columns, likely have a major role in the reactivation pattern and return of function.
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Rumbell T, Denham SL, Wennekers T. A spiking self-organizing map combining STDP, oscillations, and continuous learning. IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 2014; 25:894-907. [PMID: 24808036 DOI: 10.1109/tnnls.2013.2283140] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The self-organizing map (SOM) is a neural network algorithm to create topographically ordered spatial representations of an input data set using unsupervised learning. The SOM algorithm is inspired by the feature maps found in mammalian cortices but lacks some important functional properties of its biological equivalents. Neurons have no direct access to global information, transmit information through spikes and may be using phasic coding of spike times within synchronized oscillations, receive continuous input from the environment, do not necessarily alter network properties such as learning rate and lateral connectivity throughout training, and learn through relative timing of action potentials across a synaptic connection. In this paper, a network of integrate-and-fire neurons is presented that incorporates solutions to each of these issues through the neuron model and network structure. Results of the simulated experiments assessing map formation using artificial data as well as the Iris and Wisconsin Breast Cancer datasets show that this novel implementation maintains fundamental properties of the conventional SOM, thereby representing a significant step toward further understanding of the self-organizational properties of the brain while providing an additional method for implementing SOMs that can be utilized for future modeling in software or special purpose spiking neuron hardware.
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Négyessy L, Pálfi E, Ashaber M, Palmer C, Jákli B, Friedman RM, Chen LM, Roe AW. Intrinsic horizontal connections process global tactile features in the primary somatosensory cortex: neuroanatomical evidence. J Comp Neurol 2014; 521:2798-817. [PMID: 23436325 DOI: 10.1002/cne.23317] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 01/31/2013] [Accepted: 02/05/2013] [Indexed: 11/05/2022]
Abstract
To understand manual tactile functions in primates, it is essential to explore the interactions between the finger pad representations in somatosensory cortex. To this end, we used optical imaging and electrophysiological mapping to guide neuroanatomical tracer injections into distal digit tip representations of Brodmann area 3b in the squirrel monkey. Retrogradely labeled cell densities and anterogradely labeled fibers and terminal patches in somatosensory areas were plotted and quantified with respect to tangential distribution. Within area 3b, reciprocal patchy distribution of anterograde and retrograde labeling spanned the representation of the distal pad of multiple digits, indicating strong cross-digit connectivity. Inter-areal connections revealed bundles of long-range fibers projecting anteroposteriorly, connecting area 3b with clusters of labeled neurons and terminal axon arborizations in area 1. Inter-areal linkage appeared to be largely confined to the representation of the injected finger. These findings provide the neuroanatomical basis for the interaction between distal finger pad representations observed by recent electrophysiological studies. We propose that intra-areal connectivity may be heavily involved in interdigit integration such as shape discrimination, whereas long-range inter-areal connections may subserve active touch in a digit-specific manner.
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Affiliation(s)
- László Négyessy
- Department of Theory, Institute for Particle and Nuclear Physics, Wigner Research Center for Physics, Hungarian Academy of Sciences, Budapest H-1121, Hungary.
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Mendes RM, Barbosa RI, Salmón CEG, Rondinoni C, Escorsi-Rosset S, Delsim JC, Barbieri CH, Mazzer N. Auditory stimuli from a sensor glove model modulate cortical audiotactile integration. Neurosci Lett 2013; 548:33-7. [DOI: 10.1016/j.neulet.2013.04.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 04/03/2013] [Accepted: 04/10/2013] [Indexed: 01/22/2023]
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Han Y, Li N, Zeiler SR, Pelled G. Peripheral nerve injury induces immediate increases in layer v neuronal activity. Neurorehabil Neural Repair 2013; 27:664-72. [PMID: 23599222 DOI: 10.1177/1545968313484811] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Peripheral nerve injury leads to changes in neuronal activity in the contralateral and ipsilateral primary somatosensory cortices (S1), which may lead to enduring sensory dysfunction and pain. Plasticity in the barrel and visual cortices has been shown to occur in a layer-specific manner. However, little is known about the layer specific changes associated with limb injury. OBJECTIVE To determine the layer-specific changes in neuronal activity associated with short-term plasticity induced by peripheral nerve injury in the rat. METHODS In vivo electrophysiology recordings (multiunit activity and local field potential) and high-resolution functional magnetic resonance imaging techniques were applied to characterize neuronal and hemodynamic responses across the depth of S1 contralateral and ipsilateral to the injury. RESULTS Within 60 minutes following injury, atypical increases in neuronal and hemodynamic responses in the deprived S1, ipsilateral to the noninjured limb, were observed in response to stimulation of the noninjured limb. The most prominent increases in neuronal activity in the deprived S1 occurred in layer V. CONCLUSION Layer V neurons provide the major output of S1 and they send and receive transcallosal input. Thus, the immediate changes in neuronal firing patterns in layer V induced by the injury, can adversely affect the activity of subcortical regions and also interfere with normal cortical processing and interhemispheric communication. Therefore, a rehabilitation strategy that targets layer V neurons activity and starts immediately after the injury may benefit the functional outcome.
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Affiliation(s)
- Yang Han
- Kennedy Krieger Institute, Baltimore, MD 21205, USA
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Herrera-Rincon C, Torets C, Sanchez-Jimenez A, Avendaño C, Panetsos F. Chronic electrical stimulation of transected peripheral nerves preserves anatomy and function in the primary somatosensory cortex. Eur J Neurosci 2012; 36:3679-90. [DOI: 10.1111/ejn.12000] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2012] [Revised: 08/01/2012] [Accepted: 08/13/2012] [Indexed: 01/18/2023]
Affiliation(s)
- Celia Herrera-Rincon
- Neurocomputing and Neurorobotics Research Group; Universidad Complutense de Madrid; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC); Madrid; Spain
| | - Carlos Torets
- Neurocomputing and Neurorobotics Research Group; Universidad Complutense de Madrid; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC); Madrid; Spain
| | | | - Carlos Avendaño
- Department of Anatomy, Histology and Neuroscience; Universidad Autonoma de Madrid; Madrid; Spain
| | - Fivos Panetsos
- Neurocomputing and Neurorobotics Research Group; Universidad Complutense de Madrid; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC); Madrid; Spain
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Abstract
The mismatch negativity (MMN) is thought to index the activation of specialized neural networks for active prediction and deviance detection. However, a detailed neuronal model of the neurobiological mechanisms underlying the MMN is still lacking, and its computational foundations remain debated. We propose here a detailed neuronal model of auditory cortex, based on predictive coding, that accounts for the critical features of MMN. The model is entirely composed of spiking excitatory and inhibitory neurons interconnected in a layered cortical architecture with distinct input, predictive, and prediction error units. A spike-timing dependent learning rule, relying upon NMDA receptor synaptic transmission, allows the network to adjust its internal predictions and use a memory of the recent past inputs to anticipate on future stimuli based on transition statistics. We demonstrate that this simple architecture can account for the major empirical properties of the MMN. These include a frequency-dependent response to rare deviants, a response to unexpected repeats in alternating sequences (ABABAA…), a lack of consideration of the global sequence context, a response to sound omission, and a sensitivity of the MMN to NMDA receptor antagonists. Novel predictions are presented, and a new magnetoencephalography experiment in healthy human subjects is presented that validates our key hypothesis: the MMN results from active cortical prediction rather than passive synaptic habituation.
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Dye CA, Abbott CW, Huffman KJ. Bilateral enucleation alters gene expression and intraneocortical connections in the mouse. Neural Dev 2012; 7:5. [PMID: 22289655 PMCID: PMC3347983 DOI: 10.1186/1749-8104-7-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 01/30/2012] [Indexed: 02/08/2023] Open
Abstract
Background Anatomically and functionally distinct sensory and motor neocortical areas form during mammalian development through a process called arealization. This process is believed to be reliant on both activity-dependent and activity-independent mechanisms. Although both mechanisms are thought to function concurrently during arealization, the nature of their interaction is not understood. To examine the potential interplay of extrinsic activity-dependent mechanisms, such as sensory input, and intrinsic activity-independent mechanisms, including gene expression in mouse neocortical development, we performed bilateral enucleations in newborn mice and conducted anatomical and molecular analyses 10 days later. In this study, by surgically removing the eyes of the newborn mouse, we examined whether early enucleation would impact normal gene expression and the development of basic anatomical features such as intraneocortical connections and cortical area boundaries in the first 10 days of life, before natural eye opening. We examined the acute effects of bilateral enucleation on the lateral geniculate nucleus of the thalamus and the neocortical somatosensory-visual area boundary through detailed analyses of intraneocortical connections and gene expression of six developmentally regulated genes at postnatal day 10. Results Our results demonstrate short-term plasticity on postnatal day 10 resulting from the removal of the eyes at birth, with changes in nuclear size and gene expression within the lateral geniculate nucleus as well as a shift in intraneocortical connections and ephrin A5 expression at the somatosensory-visual boundary. In this report, we highlight the correlation between positional shifts in ephrin A5 expression and improper refinement of intraneocortical connections observed at the somatosensory-visual boundary in enucleates on postnatal day 10. Conclusions Bilateral enucleation induces a positional shift of both ephrin A5 expression and intraneocortical projections at the somatosensory-visual border in only 10 days. These changes occur prior to natural eye opening, suggesting a possible role of spontaneous retinal activity in area border formation within the neocortex. Through these analyses, we gain a deeper understanding of how extrinsic activity-dependent mechanisms, particularly input from sensory organs, are integrated with intrinsic activity-independent mechanisms to regulate neocortical arealization and plasticity.
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Affiliation(s)
- Catherine A Dye
- Department of Psychology, University of California Riverside, Riverside, CA 92521, USA
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Etchelecou MC, Coulet O, Derkenne R, Tomasi M, Noreña AJ. Temporary off-frequency listening after noise trauma. Hear Res 2011; 282:81-91. [PMID: 21986211 DOI: 10.1016/j.heares.2011.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 09/20/2011] [Accepted: 09/21/2011] [Indexed: 11/25/2022]
Abstract
Hearing loss is routinely estimated from the audiogram, even though this measure gives only a rough approximation of hearing. Indeed, cochlear regions functioning poorly, if at all, called dead regions, are not detected by a simple audiogram. To detect cochlear dead regions, additional measurements of psychophysical tuning curves or thresholds in background noise (TEN test) are required. A first aim of this study was to assess the presence of dead regions after impulse noise trauma using psychophysical tuning curves. The procedure we used was based on a compromise between the need to collect reliable estimates of psychophysical tuning curves and the limited time available to obtain these estimates in a hospital setting. Psychophysical tuning curves were measured using simultaneous masking with a 2-alternative forced choice paradigm, where the target was randomly placed in one of the two masker presentations. It is well known that some components of noise-induced hearing loss are reversible. A second aim of this study was to examine the potential recovery of dead regions after acoustic trauma. A third issue addressed in this article was the relationship between noise-induced dead regions and tinnitus. We found that 70% of the subjects had dead regions after noise trauma, while 88% reported tinnitus. Moreover, we found that the extent of dead regions probably diminished in about 50% of subjects, which highlights the ability of the human auditory system to recover from noise-induced hearing loss.
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Affiliation(s)
- M-C Etchelecou
- Laveran Hospital, 34, boulevard Laveran 13013, Marseille, France
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Farajian R, Pan F, Akopian A, Völgyi B, Bloomfield SA. Masked excitatory crosstalk between the ON and OFF visual pathways in the mammalian retina. J Physiol 2011; 589:4473-89. [PMID: 21768265 DOI: 10.1113/jphysiol.2011.213371] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
A fundamental organizing feature of the visual system is the segregation of ON and OFF responses into parallel streams to signal light increment and decrement. However, we found that blockade of GABAergic inhibition unmasks robust ON responses in OFF α-ganglion cells (α-GCs). These ON responses had the same centre-mediated structure as the classic OFF responses of OFF α-GCs, but were abolished following disruption of the ON pathway with L-AP4. Experiments showed that both GABA(A) and GABA(C) receptors are involved in the masking inhibition of this ON response, located at presynaptic inhibitory synapses on bipolar cell axon terminals and possibly amacrine cell dendrites. Since the dendrites of OFF α-GCs are not positioned to receive excitatory inputs from ON bipolar cell axon terminals in sublamina-b of the inner plexiform layer (IPL), we investigated the possibility that gap junction-mediated electrical synapses made with neighbouring amacrine cells form the avenue for reception of ON signals. We found that the application of gap junction blockers eliminated the unmasked ON responses in OFF α-GCs, while the classic OFF responses remained. Furthermore, we found that amacrine cells coupled to OFF α-GCs display processes in both sublaminae of the IPL, thus forming a plausible substrate for the reception and delivery of ON signals to OFF α-GCs. Finally, using a multielectrode array, we found that masked ON and OFF signals are displayed by over one-third of ganglion cells in the rabbit and mouse retinas, suggesting that masked crossover excitation is a widespread phenomenon in the inner mammalian retina.
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Affiliation(s)
- Reza Farajian
- Department of Physiology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
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40
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Abstract
We tested a hypothesis that the spinal plasticity induced within a few hours after nerve injury may produce changes in cortical activities and an initial phase of neuropathic pain. Somatosensory cortical responses elicited by vibratory stimulation were visualized by transcranial flavoprotein fluorescence imaging in mice. These responses were reduced immediately after cutting the sensory nerves. However, the remaining cortical responses mediated by nearby nerves were potentiated within a few hours after nerve cutting. Nerve injury induces neuropathic pain. In the present study, mice exhibited tactile allodynia 1-2 weeks after nerve injury. Lesioning of the ipsilateral dorsal column, mediating tactile cortical responses, abolished somatic cortical responses to tactile stimuli. However, nontactile cortical responses appeared in response to the same tactile stimuli within a few hours after nerve injury, indicating that tactile allodynia was acutely initiated. We investigated the trigger mechanisms underlying the cortical changes. Endogenous glial cell line-derived neurotrophic factor (GDNF), found in the Meissner corpuscles, induced basal firing ∼0.1 Hz or less in its Aβ tactile afferents, and disruption of the basal firing triggered the potentiation of nontactile cortical responses. Application of 10 nm LY341495 [(2S)-2-amino-2-[(1S,2S)-2-carboxycycloprop-1-yl]-3-(xanth-9-yl) propanoic acid], a specific antagonist of group II metabotropic glutamate receptors (mGluRs), on to the surface of the spinal cord also induced the potentiation of nontactile cortical responses. Together, it is suggested that low-frequency afferent firing produced by GDNF in touch-sensitive nerve fibers continuously activated spinal group II mGluRs and that failure of this activation triggered tactile allodynia.
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Spatiotemporal properties of neuron response suppression in owl monkey primary somatosensory cortex when stimuli are presented to both hands. J Neurosci 2011; 31:3589-601. [PMID: 21389215 DOI: 10.1523/jneurosci.4310-10.2011] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Despite the lack of ipsilateral receptive fields (RFs) for neurons in the hand representation of area 3b of primary somatosensory cortex, interhemispheric interactions have been reported to varying degrees. We investigated spatiotemporal properties of these interactions to determine the following: response types, timing between stimuli to evoke the strongest bimanual interactions, topographical distribution of effects, and their dependence on similarity of stimulus locations on the two hands. We analyzed response magnitudes and latencies of single neurons and multineuron clusters recorded from 100-electrode arrays implanted in one hemisphere of each of two anesthetized owl monkeys. Skin indentations were delivered to the two hands simultaneously and asynchronously at mirror locations (matched sites on each hand) and nonmirror locations. Since multiple neurons were recorded simultaneously, stimuli on the contralateral hand could be within or outside of the classical RFs of any given neuron. For most neurons, stimulation on the ipsilateral hand suppressed responses to stimuli on the contralateral hand. Maximum suppression occurred when the ipsilateral stimulus was presented 100 ms before the contralateral stimulus onset (p < 0.0005). The longest stimulus onset delay tested (500 ms) allowed contralateral responses to recover to control levels (p = 0.428). Stimulation on mirror digits did not differ from stimulation on nonmirror locations (p = 1.000). These results indicate that interhemispheric interactions are common in area 3b, somewhat topographically diffuse, and maximal when the suppressing ipsilateral stimulus precedes the contralateral stimulus. Our findings point to a neurophysiological basis for "interference" effects found in human psychophysical studies of bimanual stimulation.
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Rosén B, Björkman A, Lundborg G. Improving hand sensibility in vibration induced neuropathy: A case-series. J Occup Med Toxicol 2011; 6:13. [PMID: 21524297 PMCID: PMC3104948 DOI: 10.1186/1745-6673-6-13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Accepted: 04/27/2011] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES We report a long-term series of nine workers suffering from vibration-induced neuropathy, after many years of exposure to hand-held vibrating tools at high or low frequency. They were treated with temporary selective cutaneous anaesthesia (EMLA® cream) of the forearm repeatedly for a period up to one year (in two cases four years). The aim was to improve their capacity to perceive touch and thereby improve hand function and diminish disability. The treatment principle is based on current concepts of brain plasticity, where a deafferentation of a skin area results in improved sensory function in adjacent skin areas. METHODS All participants had sensory hand problems in terms of numbness (median touch thresholds > 70 mg) and impaired hand function influencing ADL (mean DASH score 22).After an initial identical self-administered treatment period of 8 weeks (12-15 treatments with increasing intervals) they did one treatment every 2-3 month. RESULTS After one year sensibility (touch thresholds and tactile discrimination) as well as hand function (mean DASH score 13) were improved in a majority of the cases. Seven of the participants choose to continue the treatment after the first year and two of them have continued at a regular basis for up to four years. A surprising, secondary finding was diminishing nocturnal numbness of the hand and arm in eight of the nine subjects from "frequently" to "hardly ever or never". CONCLUSIONS Our observations open new perspectives for treatment of impaired sensibility and hand function in a group of patients with vibration induced hand problems where we have no treatment to offer today.
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Affiliation(s)
- Birgitta Rosén
- Department of Hand Surgery, Skåne University Hospital Malmö, Sweden.
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43
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Goloshevsky AG, Wu CWH, Dodd SJ, Koretsky AP. Mapping cortical representations of the rodent forepaw and hindpaw with BOLD fMRI reveals two spatial boundaries. Neuroimage 2011; 57:526-38. [PMID: 21504796 DOI: 10.1016/j.neuroimage.2011.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 02/25/2011] [Accepted: 04/01/2011] [Indexed: 10/18/2022] Open
Abstract
Electrical stimulation of the rat forepaw and hindpaw was employed to study the spatial distribution of BOLD fMRI. Averaging of multiple fMRI sessions significantly improved the spatial stability of the BOLD signal and enabled quantitative determination of the boundaries of the BOLD fMRI maps. The averaged BOLD fMRI signal was distributed unevenly over the extent of the map and the data at the boundaries could be modeled with major and minor spatial components. Comparison of three-dimensional echo-planar imaging (EPI) fMRI at isotropic 300 μm resolution demonstrated that the border locations of the major spatial component of BOLD signal did not overlap between the forepaw and hindpaw maps. Interestingly, the border positions of the minor BOLD fMRI spatial components extended significantly into neighboring representations. Similar results were found for cerebral blood volume (CBV) weighted fMRI obtained using iron oxide particles, suggesting that the minor spatial components may not be due to vascular mislocalization typically associated with BOLD fMRI. Comparison of the BOLD fMRI maps of the forepaw and hindpaw to histological determination of these representations using cytochrome oxidase (CO) staining demonstrated that the major spatial component of the BOLD fMRI activation maps accurately localizes the borders. Finally, 2-3 weeks following peripheral nerve denervation, cortical reorganization/plasticity at the boundaries of somatosensory limb representations in adult rat brain was studied. Denervation of the hindpaw caused a growth in the major component of forepaw representation into the adjacent border of hindpaw representation, such that fitting to two components no longer led to a better fit as compared to using one major component. The border of the representation after plasticity was the same as the border of its minor component in the absence of any plasticity. It is possible that the minor components represent either vascular effects that extend from the real neuronal representations or the neuronal communication between neighboring regions. Either way the results will be useful for studying mechanisms of plasticity that cause alterations in the boundaries of neuronal representations.
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Affiliation(s)
- Artem G Goloshevsky
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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Stump nerve signals during transcranial magnetic motor cortex stimulation recorded in an amputee via longitudinal intrafascicular electrodes. Exp Brain Res 2011; 210:1-11. [DOI: 10.1007/s00221-011-2571-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Accepted: 01/24/2011] [Indexed: 10/18/2022]
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Pienkowski M, Eggermont JJ. Cortical tonotopic map plasticity and behavior. Neurosci Biobehav Rev 2011; 35:2117-28. [PMID: 21315757 DOI: 10.1016/j.neubiorev.2011.02.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 02/02/2011] [Accepted: 02/04/2011] [Indexed: 11/16/2022]
Abstract
Central topographic representations of sensory epithelia have a genetic basis, but are refined by patterns of afferent input and by behavioral demands. Here we review such experience-driven map development and plasticity, focusing on the auditory system, and giving particular consideration to its adaptive value and to the putative mechanisms involved. Recent data have challenged the widely held notion that only the developing auditory brain can be influenced by changes to the prevailing acoustic environment, unless those changes convey information of behavioral relevance. Specifically, it has been shown that persistent exposure of adult animals to random, bandlimited, moderately loud sounds can lead to a reorganization of auditory cortex not unlike that following restricted hearing loss. The mature auditory brain is thus more plastic than previously supposed, with potentially troubling consequences for those working or living in noisy environments, even at exposure levels considerably below those presently considered just-acceptable.
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Affiliation(s)
- Martin Pienkowski
- Hotchkiss Brain Institute, Departments of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
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Chrostowski M, Yang L, Wilson HR, Bruce IC, Becker S. Can homeostatic plasticity in deafferented primary auditory cortex lead to travelling waves of excitation? J Comput Neurosci 2010; 30:279-99. [PMID: 20623168 DOI: 10.1007/s10827-010-0256-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Revised: 06/06/2010] [Accepted: 06/18/2010] [Indexed: 12/19/2022]
Abstract
Travelling waves of activity in neural circuits have been proposed as a mechanism underlying a variety of neurological disorders, including epileptic seizures, migraine auras and brain injury. The highly influential Wilson-Cowan cortical model describes the dynamics of a network of excitatory and inhibitory neurons. The Wilson-Cowan equations predict travelling waves of activity in rate-based models that have sufficiently reduced levels of lateral inhibition. Travelling waves of excitation may play a role in functional changes in the auditory cortex after hearing loss. We propose that down-regulation of lateral inhibition may be induced in deafferented cortex via homeostatic plasticity mechanisms. We use the Wilson-Cowan equations to construct a spiking model of the primary auditory cortex that includes a novel, mathematically formalized description of homeostatic plasticity. In our model, the homeostatic mechanisms respond to hearing loss by reducing inhibition and increasing excitation, producing conditions under which travelling waves of excitation can emerge. However, our model predicts that the presence of spontaneous activity prevents the development of long-range travelling waves of excitation. Rather, our simulations show short-duration excitatory waves that cancel each other out. We also describe changes in spontaneous firing, synchrony and tuning after simulated hearing loss. With the exception of shifts in characteristic frequency, changes after hearing loss were qualitatively the same as empirical findings. Finally, we discuss possible applications to tinnitus, the perception of sound without an external stimulus.
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Affiliation(s)
- Michael Chrostowski
- McMaster Integrative Neuroscience Discovery & Study, McMaster University, 1280 Main Street West, Hamilton, ON, Canada.
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Rajan R, Irvine DRF. Severe and extensive neonatal hearing loss in cats results in auditory cortex plasticity that differentiates into two regions. Eur J Neurosci 2010; 31:1999-2013. [PMID: 20497473 DOI: 10.1111/j.1460-9568.2010.07214.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
We examined the response characteristics of primary auditory cortex (A1) neurons in adult cats partially but extensively deafened by ototoxic drugs 2-8 days after birth. The damage evoked extensive A1 topographic map reorganization as also found by others, but a novel finding was that in the majority of cats with low-frequency edges to the cochlear lesion, the area of reorganization segregated into two areas expressing the same novel frequency inputs but differentiated by neuronal sensitivity and responsiveness. Immediately adjacent to normal A1 is an approximately 1.2-mm-wide area of reorganization in which sensitivity and responsiveness to sound are similar to that in normal A1 in the same animals and in unlesioned adult animals. Extending further into deprived A1 is a more extensive area of reorganization where neurons have poorer sensitivity and responsiveness to new inputs. These two areas did not differ in response-area bandwidth and response latency. We interpret these novel changes as the cortical consequences of severe receptor organ lesions extending to low-frequency cochlear regions. We speculate that the two areas of A1 reorganization may reflect differences in the transcortical spatial distribution of thalamo-cortical and horizontal intracortical connections. Qualitatively similar changes in response properties have been seen after retinal lesions producing large areas of visual cortical reorganization, suggesting they might be a general consequence of receptor lesions that deprive large regions of cortex of normal input. These effects may have perceptual implications for the use of cochlear implants in patients with residual low-frequency hearing.
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Affiliation(s)
- R Rajan
- Department of Physiology, Monash University, Vic. 3800, Australia.
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Bieszczad KM, Weinberger NM. Remodeling the cortex in memory: Increased use of a learning strategy increases the representational area of relevant acoustic cues. Neurobiol Learn Mem 2010; 94:127-44. [PMID: 20434577 DOI: 10.1016/j.nlm.2010.04.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 04/20/2010] [Accepted: 04/24/2010] [Indexed: 11/28/2022]
Abstract
Associative learning induces plasticity in the representation of sensory information in sensory cortices. Such high-order associative representational plasticity (HARP) in the primary auditory cortex (A1) is a likely substrate of auditory memory: it is specific, rapidly acquired, long-lasting and consolidates. Because HARP is likely to support the detailed content of memory, it is important to identify the necessary behavioral factors that dictate its induction. Learning strategy is a critical factor for the induction of plasticity (Bieszczad & Weinberger, 2010b). Specifically, use of a strategy that relies on tone onsets induces HARP in A1 in the form of signal-specific decreased threshold and bandwidth. The present study tested the hypothesis that the form and degree of HARP in A1 reflects the amount of use of an "onset strategy". Adult male rats (n=7) were trained in a protocol that increased the use of this strategy from approximately 20% in prior studies to approximately 80%. They developed signal-specific gains in representational area, transcending plasticity in the form of local changes in threshold and bandwidth. Furthermore, the degree of area gain was proportional to the amount of use of the onset strategy. A second complementary experiment demonstrated that use of a learning strategy that specifically did not rely on tone onsets did not produce gains in representational area; but rather produced area loss. Together, the findings indicate that the amount of strategy use is a dominant factor for the induction of learning-induced cortical plasticity along a continuum of both form and degree.
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Affiliation(s)
- Kasia M Bieszczad
- Center for the Neurobiology of Learning and Memory, Department of Neurobiology and Behavior, University of California Irvine, CA 92697-3800, United States
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Reed JL, Qi HX, Zhou Z, Bernard MR, Burish MJ, Bonds AB, Kaas JH. Response properties of neurons in primary somatosensory cortex of owl monkeys reflect widespread spatiotemporal integration. J Neurophysiol 2010; 103:2139-57. [PMID: 20164400 PMCID: PMC2853283 DOI: 10.1152/jn.00709.2009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 02/11/2010] [Indexed: 11/22/2022] Open
Abstract
Receptive fields of neurons in somatosensory area 3b of monkeys are typically described as restricted to part of a single digit or palm pad. However, such neurons are likely involved in integrating stimulus information from across the hand. To evaluate this possibility, we recorded from area 3b neurons in anesthetized owl monkeys with 100-electrode arrays, stimulating two hand locations with electromechanical probes simultaneously or asynchronously. Response magnitudes and latencies of single- and multiunits varied with stimulus conditions, and multiunit responses were similar to single-unit responses. The mean peak firing rate for single neurons stimulated within the preferred location was estimated to be ∼26 spike/s. Simultaneous stimulation with a second probe outside the preferred location slightly decreased peak firing rates to ∼22 spike/s. When the nonpreferred stimulus preceded the preferred stimulus by 10-500 ms, peak firing rates were suppressed with greatest suppression when the nonpreferred stimulus preceded by 30 ms (∼7 spike/s). The mean latency for single neurons stimulated within the preferred location was ∼23 ms, and latency was little affected by simultaneous paired stimulation. However, when the nonpreferred stimulus preceded the preferred stimulus by 10 ms, latencies shortened to ∼16 ms. Response suppression occurred even when stimuli were separated by long distances (nonadjacent digits) or long times (500 ms onset asynchrony). Facilitation, though rare, occurred most often when the stimulus onsets were within 0-30 ms of each other. These findings quantify spatiotemporal interactions and support the hypothesis that area 3b is involved in widespread stimulus integration.
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Affiliation(s)
- Jamie L Reed
- Dept. of Psychology, Vanderbilt University, 111 21st Ave. S., Nashville, TN 37240, USA.
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May PJC, Tiitinen H. Mismatch negativity (MMN), the deviance-elicited auditory deflection, explained. Psychophysiology 2010; 47:66-122. [DOI: 10.1111/j.1469-8986.2009.00856.x] [Citation(s) in RCA: 374] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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