1
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Sacco A, Gordon SG, Lomber SG. Gray matter volume of the feline cerebral cortex and structural plasticity following perinatal deafness. Neuroimage 2024; 299:120813. [PMID: 39182711 DOI: 10.1016/j.neuroimage.2024.120813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 08/12/2024] [Accepted: 08/22/2024] [Indexed: 08/27/2024] Open
Abstract
In response to sensory deprivation, the brain adapts according to contemporary demands to efficiently navigate a modified perceptual environment. This reorganization may result in improved processing of the remaining senses-a phenomenon referred to as compensatory crossmodal plasticity. One approach to explore this neuroplasticity is to consider the macrostructural changes in neural tissue that mirror this functional optimization. The current study is the first of its kind to measure MRI-derived gray matter (GM) volumes of control felines (n=30), while additionally identifying volumetric differences in response to perinatal deafness (30 ototoxically-deafened cats). To accomplish this purpose, regional and morphometric methods were performed in parallel. The regional analysis evaluated volumetric alterations of global GM, as well as the volumes of 146 regions of interest (ROIs) and 12 functional subgroupings of these ROIs. Results revealed whole-brain GM preservation; however, somatosensory and visual cortices exhibited an overall increase in volume. On a smaller scale, this analysis uncovered two auditory ROIs (second auditory cortex, A2, and ventral auditory field, VAF) that decreased in volume alongside two visual regions (anteromedial lateral suprasylvian area, AMLS and splenial visual area, SVA) that increased-all localized within the right hemisphere. Comparatively, the findings of tensor-based morphometry (TBM) generally aligned with those of the ROI-based method, as this voxel-wise approach demonstrated clusters of expansion coincident with visual- and somatosensory-related loci; although, it failed to detect any GM reductions following deafness. As distinct differences were identified in each analysis, the current study highlights the importance of employing multiple methods when exploring MRI volumetry. Overall, this study proposes that volumetric alterations within sensory loci allude to a redistribution of cortical space arising from modified perceptual demands following auditory deprivation.
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Affiliation(s)
- Alessandra Sacco
- Integrated Program in Nseuroscience, McGill University, Montreal, Quebec, Canada
| | - Stephen G Gordon
- Integrated Program in Nseuroscience, McGill University, Montreal, Quebec, Canada
| | - Stephen G Lomber
- Integrated Program in Nseuroscience, McGill University, Montreal, Quebec, Canada; Department of Physiology, McGill University, Montreal, Quebec, Canada.
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2
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Gay JD, Dangcil E, Nacipucha J, Botrous JE, Suresh N, Tucker A, Carayannopoulos NL, Khan MR, Meng R, Yao JD, Wackym PA, Mowery TM. An Animal Model of Neonatal Intensive Care Unit Exposure to Light and Sound in the Preterm Infant. Integr Comp Biol 2023; 63:585-596. [PMID: 37164937 PMCID: PMC10503467 DOI: 10.1093/icb/icad020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/19/2023] [Accepted: 04/21/2023] [Indexed: 05/12/2023] Open
Abstract
According to the World Health Organization, ∼15 million children are born prematurely each year. Many of these infants end up spending days to weeks in a neonatal intensive care unit (NICU). Infants who are born prematurely are often exposed to noise and light levels that affect their auditory and visual development. Children often have long-term impairments in cognition, visuospatial processing, hearing, and language. We have developed a rodent model of NICU exposure to light and sound using the Mongolian gerbil (Meriones unguiculatus), which has a low-frequency human-like audiogram and is altricial. To simulate preterm infancy, the eyes and ears were opened prematurely, and animals were exposed to the NICU-like sensory environment throughout the gerbil's cortical critical period of auditory development. After the animals matured into adults, auditory perceptual testing was carried out followed by auditory brainstem response recordings and then histology to assess the white matter morphology of various brain regions. Compared to normal hearing control animals, NICU sensory-exposed animals had significant impairments in learning at later stages of training, increased auditory thresholds reflecting hearing loss, and smaller cerebellar white matter volumes. These have all been reported in longitudinal studies of preterm infants. These preliminary results suggest that this animal model could provide researchers with an ethical way to explore the effects of the sensory environment in the NICU on the preterm infant's brain development.
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Affiliation(s)
- Jennifer D Gay
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
- Rutgers Brain Health Institute, New Brunswick, NJ, USA
| | - Evelynne Dangcil
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Jacqueline Nacipucha
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Jonathon E Botrous
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Nikhil Suresh
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Aaron Tucker
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Nicolas L Carayannopoulos
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Muhammad R Khan
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Raphael Meng
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Justin D Yao
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
- Rutgers Brain Health Institute, New Brunswick, NJ, USA
| | - P Ashley Wackym
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
- Rutgers Brain Health Institute, New Brunswick, NJ, USA
| | - Todd M Mowery
- Department of Otolaryngology—Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
- Rutgers Brain Health Institute, New Brunswick, NJ, USA
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3
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Cui W, Wang S, Chen B, Fan G. White matter structural network alterations in congenital bilateral profound sensorineural hearing loss children: A graph theory analysis. Hear Res 2022; 422:108521. [PMID: 35660126 DOI: 10.1016/j.heares.2022.108521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 03/22/2022] [Accepted: 05/14/2022] [Indexed: 11/25/2022]
Abstract
Functional magnetic resonance imaging (fMRI) studies have revealed a functional reorganization in patients with sensorineural hearing loss (SNHL). The structural basement of functional changes has also been investigated recently. Graph theory analysis brings a new understanding of the structural connectome and topological features in central neural system diseases. However, little is known about the structural network connectome changes in SNHL patients, especially in children. We explored the differences in topologic organization, rich-club organization, and structural connection between children with congenital bilateral profound SNHL and normal hearing under the age of three using graph theory analysis and probabilistic tractography. Compared with the normal-hearing (NH) group, the SNHL group showed no difference in global and nodal topological parameters. Increased structural connection strength were found in the right cortico-striatal-thalamus-cortical circuity. Decreased cross-hemisphere connections were found between the right precuneus and the left auditory cortex as well as the left subcortical regions. Rich-club organization analysis found increased local connection in the SNHL group. These results revealed structural organizations after hearing deprivation in congenital bilateral profound SNHL children.
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Affiliation(s)
- Wenzhuo Cui
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, LN, China
| | - Shanshan Wang
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, LN, China
| | - Boyu Chen
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, LN, China
| | - Guoguang Fan
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, LN, China.
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4
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Grégoire A, Deggouj N, Dricot L, Decat M, Kupers R. Brain Morphological Modifications in Congenital and Acquired Auditory Deprivation: A Systematic Review and Coordinate-Based Meta-Analysis. Front Neurosci 2022; 16:850245. [PMID: 35418829 PMCID: PMC8995770 DOI: 10.3389/fnins.2022.850245] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 03/01/2022] [Indexed: 12/02/2022] Open
Abstract
Neuroplasticity following deafness has been widely demonstrated in both humans and animals, but the anatomical substrate of these changes is not yet clear in human brain. However, it is of high importance since hearing loss is a growing problem due to aging population. Moreover, knowing these brain changes could help to understand some disappointing results with cochlear implant, and therefore could improve hearing rehabilitation. A systematic review and a coordinate-based meta-analysis were realized about the morphological brain changes highlighted by MRI in severe to profound hearing loss, congenital and acquired before or after language onset. 25 papers were included in our review, concerning more than 400 deaf subjects, most of them presenting prelingual deafness. The most consistent finding is a volumetric decrease in gray matter around bilateral auditory cortex. This change was confirmed by the coordinate-based meta-analysis which shows three converging clusters in this region. The visual areas of deaf children is also significantly impacted, with a decrease of the volume of both gray and white matters. Finally, deafness is responsible of a gray matter increase within the cerebellum, especially at the right side. These results are largely discussed and compared with those from deaf animal models and blind humans, which demonstrate for example a much more consistent gray matter decrease along their respective primary sensory pathway. In human deafness, a lot of other factors than deafness could interact on the brain plasticity. One of the most important is the use of sign language and its age of acquisition, which induce among others changes within the hand motor region and the visual cortex. But other confounding factors exist which have been too little considered in the current literature, such as the etiology of the hearing impairment, the speech-reading ability, the hearing aid use, the frequent associated vestibular dysfunction or neurocognitive impairment. Another important weakness highlighted by this review concern the lack of papers about postlingual deafness, whereas it represents most of the deaf population. Further studies are needed to better understand these issues, and finally try to improve deafness rehabilitation.
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Affiliation(s)
- Anaïs Grégoire
- Department of ENT, Cliniques Universitaires Saint-Luc, Brussels, Belgium
- Institute of NeuroScience (IoNS), UCLouvain, Brussels, Belgium
| | - Naïma Deggouj
- Department of ENT, Cliniques Universitaires Saint-Luc, Brussels, Belgium
- Institute of NeuroScience (IoNS), UCLouvain, Brussels, Belgium
| | - Laurence Dricot
- Institute of NeuroScience (IoNS), UCLouvain, Brussels, Belgium
| | - Monique Decat
- Department of ENT, Cliniques Universitaires Saint-Luc, Brussels, Belgium
- Institute of NeuroScience (IoNS), UCLouvain, Brussels, Belgium
| | - Ron Kupers
- Institute of NeuroScience (IoNS), UCLouvain, Brussels, Belgium
- Department of Neuroscience, Panum Institute, University of Copenhagen, Copenhagen, Denmark
- Ecole d’Optométrie, Université de Montréal, Montréal, QC, Canada
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5
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Kiwitz K, Brandstetter A, Schiffer C, Bludau S, Mohlberg H, Omidyeganeh M, Massicotte P, Amunts K. Cytoarchitectonic Maps of the Human Metathalamus in 3D Space. Front Neuroanat 2022; 16:837485. [PMID: 35350721 PMCID: PMC8957853 DOI: 10.3389/fnana.2022.837485] [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: 12/16/2021] [Accepted: 01/18/2022] [Indexed: 11/13/2022] Open
Abstract
The human metathalamus plays an important role in processing visual and auditory information. Understanding its layers and subdivisions is important to gain insights in its function as a subcortical relay station and involvement in various pathologies. Yet, detailed histological references of the microanatomy in 3D space are still missing. We therefore aim at providing cytoarchitectonic maps of the medial geniculate body (MGB) and its subdivisions in the BigBrain – a high-resolution 3D-reconstructed histological model of the human brain, as well as probabilistic cytoarchitectonic maps of the MGB and lateral geniculate body (LGB). Therefore, histological sections of ten postmortem brains were studied. Three MGB subdivisions (MGBv, MGBd, MGBm) were identified on every 5th BigBrain section, and a deep-learning based tool was applied to map them on every remaining section. The maps were 3D-reconstructed to show the shape and extent of the MGB and its subdivisions with cellular precision. The LGB and MGB were additionally identified in nine other postmortem brains. Probabilistic cytoarchitectonic maps in the MNI “Colin27” and MNI ICBM152 reference spaces were computed which reveal an overall low interindividual variability in topography and extent. The probabilistic maps were included into the Julich-Brain atlas, and are freely available. They can be linked to other 3D data of human brain organization and serve as an anatomical reference for diagnostic, prognostic and therapeutic neuroimaging studies of healthy brains and patients. Furthermore, the high-resolution MGB BigBrain maps provide a basis for data integration, brain modeling and simulation to bridge the larger scale involvement of thalamocortical and local subcortical circuits.
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Affiliation(s)
- Kai Kiwitz
- Cécile and Oskar Vogt Institute of Brain Research, University Hospital Düsseldorf, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
- Max Planck School of Cognition, Stephanstraße 1a, Leipzig, Germany
- *Correspondence: Kai Kiwitz,
| | - Andrea Brandstetter
- Institute of Neuroscience and Medicine (INM-1), Forschungszentrum Jülich, Jülich, Germany
| | - Christian Schiffer
- Institute of Neuroscience and Medicine (INM-1), Forschungszentrum Jülich, Jülich, Germany
- Helmholtz AI, Forschungszentrum Jülich, Jülich, Germany
| | - Sebastian Bludau
- Institute of Neuroscience and Medicine (INM-1), Forschungszentrum Jülich, Jülich, Germany
| | - Hartmut Mohlberg
- Institute of Neuroscience and Medicine (INM-1), Forschungszentrum Jülich, Jülich, Germany
| | - Mona Omidyeganeh
- McGill Centre for Integrative Neuroscience, McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- National Research Council of Canada, Ottawa, ON, Canada
| | - Philippe Massicotte
- McGill Centre for Integrative Neuroscience, McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Katrin Amunts
- Cécile and Oskar Vogt Institute of Brain Research, University Hospital Düsseldorf, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
- Max Planck School of Cognition, Stephanstraße 1a, Leipzig, Germany
- Institute of Neuroscience and Medicine (INM-1), Forschungszentrum Jülich, Jülich, Germany
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6
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Abstract
The auditory cortex of people with sensorineural hearing loss can be re-afferented using a cochlear implant (CI): a neural prosthesis that bypasses the damaged cells in the cochlea to directly stimulate the auditory nerve. Although CIs are the most successful neural prosthesis to date, some CI users still do not achieve satisfactory outcomes using these devices. To explain variability in outcomes, clinicians and researchers have increasingly focused their attention on neuroscientific investigations that examined how the auditory cortices respond to the electric signals that originate from the CI. This chapter provides an overview of the literature that examined how the auditory cortex changes its functional properties in response to inputs from the CI, in animal models and in humans. We focus first on the basic responses to sounds delivered through electrical hearing and, next, we examine the integrity of two fundamental aspects of the auditory system: tonotopy and processing of binaural cues. When addressing the effects of CIs in humans, we also consider speech-evoked responses. We conclude by discussing to what extent this neuroscientific literature can contribute to clinical practices and help to overcome variability in outcomes.
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Affiliation(s)
- Francesco Pavani
- Center for Mind/Brain Sciences - CIMeC, University of Trento, Rovereto, Italy.
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7
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Wang S, Chen B, Yu Y, Yang H, Cui W, Fan G, Li J. Altered resting-state functional network connectivity in profound sensorineural hearing loss infants within an early sensitive period: A group ICA study. Hum Brain Mapp 2021; 42:4314-4326. [PMID: 34060682 PMCID: PMC8356983 DOI: 10.1002/hbm.25548] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/29/2021] [Accepted: 05/20/2021] [Indexed: 12/21/2022] Open
Abstract
Data from both animal models and deaf children provide evidence for that the maturation of auditory cortex has a sensitive period during the first 2-4 years of life. During this period, the auditory stimulation can affect the development of cortical function to the greatest extent. Thus far, little is known about the brain development trajectory after early auditory deprivation within this period. In this study, independent component analysis (ICA) technique was used to detect the characteristics of brain network development in children with bilateral profound sensorineural hearing loss (SNHL) before 3 years old. Seven resting-state networks (RSN) were identified in 50 SNHL and 36 healthy controls using ICA method, and further their intra-and inter-network functional connectivity (FC) were compared between two groups. Compared with the control group, SNHL group showed decreased FC within default mode network, while enhanced FC within auditory network (AUN) and salience network. No significant changes in FC were found in the visual network (VN) and sensorimotor network (SMN). Furthermore, the inter-network FC between SMN and AUN, frontal network and AUN, SMN and VN, frontal network and VN were significantly increased in SNHL group. The results implicate that the loss and the compensatory reorganization of brain network FC coexist in SNHL infants. It provides a network basis for understanding the brain development trajectory after hearing loss within early sensitive period.
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Affiliation(s)
- Shanshan Wang
- Department of Radiology, The First Hospital, China Medical University, Shenyang, Liaoning, China
| | - Boyu Chen
- Department of Radiology, The First Hospital, China Medical University, Shenyang, Liaoning, China
| | - Yalian Yu
- Department of Otorhinolaryngology, The First Hospital, China Medical University, Shenyang, Liaoning, China
| | - Huaguang Yang
- Department of Radiology, Renmin Hospital, Wuhan University, Wuhan, China
| | - Wenzhuo Cui
- Department of Radiology, The First Hospital, China Medical University, Shenyang, Liaoning, China
| | - Guoguang Fan
- Department of Radiology, The First Hospital, China Medical University, Shenyang, Liaoning, China
| | - Jian Li
- Department of Radiology, The First Hospital, China Medical University, Shenyang, Liaoning, China
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8
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Development of Auditory Cortex Circuits. J Assoc Res Otolaryngol 2021; 22:237-259. [PMID: 33909161 DOI: 10.1007/s10162-021-00794-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 03/03/2021] [Indexed: 02/03/2023] Open
Abstract
The ability to process and perceive sensory stimuli is an essential function for animals. Among the sensory modalities, audition is crucial for communication, pleasure, care for the young, and perceiving threats. The auditory cortex (ACtx) is a key sound processing region that combines ascending signals from the auditory periphery and inputs from other sensory and non-sensory regions. The development of ACtx is a protracted process starting prenatally and requires the complex interplay of molecular programs, spontaneous activity, and sensory experience. Here, we review the development of thalamic and cortical auditory circuits during pre- and early post-natal periods.
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9
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Meredith MA, Kay JM, Lomber SG, Clemo HR. Early hearing loss induces plasticity within extra-striate visual cortex. Eur J Neurosci 2021; 53:1950-1960. [PMID: 33387377 DOI: 10.1111/ejn.15104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 11/12/2020] [Accepted: 12/22/2020] [Indexed: 11/29/2022]
Abstract
Supranormal perceptual performance has been observed within the intact senses of early-deaf or blind humans and animals. For cortical areas deprived of their normal sensory input, numerous studies have shown that the lesioned modality is replaced by that of the intact sensory modalities through a process termed crossmodal plasticity. In contrast, little is known about the effects of loss of a particular sensory modality on the cortical representations of the remaining, intact sensory modalities. In the present study, an area of extrastriate visual cortex from early-deaf adult cats was examined for features of dendritic plasticity known to occur after early-deafness. Using light-microscopy of Golgi-stained pyramidal neurons from the posterolateral lateral suprasylvian (PLLS) cortex, dendritic spine density significantly increased (~19%), while spine head size was slightly but significantly decreased (~9%) following early hearing loss. Curiously, these changes were not localized to regions of the visual PLLS known to receive auditory inputs, but instead showed a broad pattern more reflective of the distribution of the area's visual features. Whereas hearing loss results in crossmodal plasticity in auditory cortices, the same peripheral lesion can also induce intramodal plasticity within representations of the intact sensory systems that may also contribute to supranormal performance.
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Affiliation(s)
- M Alex Meredith
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - John M Kay
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Stephen G Lomber
- Department of Physiology, Department of Neurology and Neurosurgery, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - H Ruth Clemo
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
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10
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Altered Gray Matter Volume and White Matter Integrity in Sensorineural Hearing Loss Patients: A VBM and TBSS Study. Otol Neurotol 2020; 40:e569-e574. [PMID: 31157719 DOI: 10.1097/mao.0000000000002273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The purpose of the present study was to detect structural changes in the brains of patients with sensorineural hearing loss (SNHL) by combining voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS). METHODS Thirty-five patients with SNHL (mean age: 39.72 ± 1.81 yr) and 23 age-matched control subjects (mean age: 39.83 ± 1.96 yr) were assessed using three-dimensional, T1-weighted imaging, and diffusion tensor imaging. TBSS and VBM analyses were performed to evaluate grey matter (GM) volume changes and white matter (WM) alternations, as measured by mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD). RESULTS VBM showed decreased GM volume in patients with SNHL in the fusiform gyrus of the right temporal lobe and right middle occipital gyrus. TBSS revealed WM integrity changes, including decreased FA and RD and increased RD in several WM regions. However, MD showed no significant difference between patients with SNHL and age-matched controls. CONCLUSION Patients with SNHL showed smaller GM volume and WM integrity changes in several regions.
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11
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Wong C, Pearson KG, Lomber SG. Contributions of Parietal Cortex to the Working Memory of an Obstacle Acquired Visually or Tactilely in the Locomoting Cat. Cereb Cortex 2019; 28:3143-3158. [PMID: 28981640 DOI: 10.1093/cercor/bhx186] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Indexed: 01/15/2023] Open
Abstract
A working memory of obstacles is essential for navigating complex, cluttered terrain. In quadrupeds, it has been proposed that parietal cortical areas related to movement planning and working memory may be important for guiding the hindlegs over an obstacle previously cleared by the forelegs. To test this hypothesis, parietal areas 5 and 7 were reversibly deactivated in walking cats. The working memory of an obstacle was assessed in both a visually dependent and tactilely dependent paradigm. Reversible bilateral deactivation of area 5, but not area 7, altered hindleg stepping in a manner indicating that the animals did not recall the obstacle over which their forelegs had stepped. Similar deficits were observed when area 5 deactivation was restricted to the delay during which obstacle memory must be maintained. Furthermore, partial memory recovery observed when area 5 function was deactivated and restored within this maintenance period suggests that the deactivation may suppress, but not eliminate, the working memory of an obstacle. As area 5 deactivations incurred similar memory deficits in both visual and tactile obstacle working memory paradigms, parietal area 5 is critical for maintaining the working memory of an obstacle acquired via vision or touch that is used to modify stepping for avoidance.
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Affiliation(s)
- Carmen Wong
- Cerebral Systems Laboratory, University of Western Ontario, London, Ontario, Canada.,Graduate Program in Neuroscience, University of Western Ontario, London, Ontario, Canada
| | - Keir G Pearson
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Stephen G Lomber
- Cerebral Systems Laboratory, University of Western Ontario, London, Ontario, Canada.,Graduate Program in Neuroscience, University of Western Ontario, London, Ontario, Canada.,Brain and Mind Institute, University of Western Ontario, London, Ontario, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.,Department of Psychology, University of Western Ontario, London, Ontario, Canada
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12
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Wang S, Chen B, Yu Y, Yang H, Cui W, Li J, Fan GG. Alterations of structural and functional connectivity in profound sensorineural hearing loss infants within an early sensitive period: A combined DTI and fMRI study. Dev Cogn Neurosci 2019; 38:100654. [PMID: 31129460 PMCID: PMC6969342 DOI: 10.1016/j.dcn.2019.100654] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 04/30/2019] [Accepted: 05/03/2019] [Indexed: 12/02/2022] Open
Abstract
Due to heightened level of neuroplasticity, there is a sensitive period (2-4 years after birth) that exists for optimal central auditory development. Using diffusion tensor imaging combined with resting-state functional connectivity (rsFC) analysis, this study directly investigates the structural connectivity alterations of the whole brain white matter (WM) and the functional reorganization of the auditory network in infants with sensorineural hearing loss (SNHL) during the early sensitive period. 46 bilateral profound SNHL infants prior to cochlear implantation (mean age, 17.59 months) and 33 healthy controls (mean age, 18.55 months) were included in the analysis. Compared with controls, SNHL infants showed widespread WM alterations, including bilateral superior longitudinal fasciculus, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, right corticospinal tract, posterior thalamic radiation and left uncinate fasciculus. Moreover, SNHL infants demonstrated increased rsFC between left/right primary auditory cortex seeds and right insula and superior temporal gyrus. In conclusion, this study suggests that SNHL in the early sensitive period is associated with diffuse WM alterations that mainly affect the auditory and language pathways. Furthermore, increased rsFC in areas mainly associated with auditory and language networks may potentially reflect reorganization and compensatory activation in response to auditory deprivation during the early sensitive period.
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Affiliation(s)
- Shanshan Wang
- Department of Radiology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China
| | - Boyu Chen
- Department of Radiology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China
| | - Yalian Yu
- Department of Otorhinolaryngology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China
| | - Huaguang Yang
- Department of Radiology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China
| | - Wenzhuo Cui
- Department of Radiology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China
| | - Jian Li
- Department of Radiology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China
| | - Guo Guang Fan
- Department of Radiology, The First Hospital, China Medical University, #155, Nanjing North St., Heping Dist., Shenyang, Liaoning 110001, China.
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13
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Abstract
Over the past decade, there has been an unprecedented level of interest and progress into understanding visual processing in the brain of the deaf. Specifically, when the brain is deprived of input from one sensory modality (such as hearing), it often compensates with supranormal performance in one or more of the intact sensory systems (such as vision). Recent psychophysical, functional imaging, and reversible deactivation studies have converged to define the specific visual abilities that are enhanced in the deaf, as well as the cortical loci that undergo crossmodal plasticity in the deaf and are responsible for mediating these superior visual functions. Examination of these investigations reveals that central visual functions, such as object and facial discrimination, and peripheral visual functions, such as motion detection, visual localization, visuomotor synchronization, and Vernier acuity (measured in the periphery), are specifically enhanced in the deaf, compared with hearing participants. Furthermore, the cortical loci identified to mediate these functions reside in deaf auditory cortex: BA 41, BA 42, and BA 22, in addition to the rostral area, planum temporale, Te3, and temporal voice area in humans; primary auditory cortex, anterior auditory field, dorsal zone of auditory cortex, auditory field of the anterior ectosylvian sulcus, and posterior auditory field in cats; and primary auditory cortex and anterior auditory field in both ferrets and mice. Overall, the findings from these studies show that crossmodal reorganization in auditory cortex of the deaf is responsible for the superior visual abilities of the deaf.
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Microstructural Alterations in the Brains of Adults With Prelingual Sensorineural Hearing Loss: a Diffusion Kurtosis Imaging Study. Otol Neurotol 2018; 39:e936-e943. [DOI: 10.1097/mao.0000000000002000] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Han JJ, Lee HS, Park MH. Neuroplastic change of cytoskeleton in inferior colliculus after auditory deafferentation. Hear Res 2018; 367:207-212. [PMID: 29954642 DOI: 10.1016/j.heares.2018.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/07/2018] [Accepted: 06/13/2018] [Indexed: 10/28/2022]
Abstract
Neural plasticity is a characteristic of the brain that helps it adapt to changes in sensory input. We hypothesize that auditory deafferentation may induce plastic changes in the cytoskeleton of the neurons in the inferior colliculus (IC). In this study, we evaluated the dynamic status of neurofilament (NF) phosphorylation in the IC after hearing loss. We induced auditory deafferentation via unilateral or bilateral cochlear ablation in rats, aged 4 weeks. To evaluate cytoskeletal changes in neurons, we evaluated mRNA fold changes in NF heavy chain expression, non-phosphorylated NF protein fold changes using SMI-32 antibody, and the ratio of SMI-32 immunoreactive (SMI-32-ir) neurons to the total neuronal population in the IC at 4 and 12 weeks after deafness. In the bilateral deafness (BD) group, the ratios of SMI-32-ir neurons significantly increased at 4 weeks after ablation in the right and left IC (6.1 ± 4.4%, 5.0 ± 3.4%, respectively), compared with age-matched controls (P < 0.01, P < 0.01). At 12 weeks after ablation, the ratio of SMI-32 positive neurons was higher (right, 3.4 ± 2.0%; left, 3.2 ± 2.3%) than that in the age-matched control group, albeit not significant in the right and left side (P = 0.38, P = 0.24, respectively). Consistent with the results of the ratio of SMI-32-ir neurons, SMI-32-ir protein expression was increased at 4 weeks after BD, and the changes at 12 weeks after bilateral ablation were not significant in the right or left IC. The age-matched control fold changes of NF mRNA expression after bilateral deafness were not significant at 4 and 12 weeks after deafness in right and left IC. Unilateral deafness did not induce significant change of NF mRNA expression, SMI-32-ir protein expression, and the ratio of SMI-32-ir neurons in the IC at 4 and 12 weeks after hearing loss. Bilateral auditory deafferentation induces structural changes in the neuronal cytoskeleton within the IC, which is prominent at 4 weeks after BD. The structural remodeling of neurons stabilized at 12 weeks after BD. Unlike BD, unilateral auditory deafferentation did not affect the dynamic status of NFs in the IC.
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Affiliation(s)
- Jae Joon Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Ho Sun Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Boramae Medical Center, Seoul Metropolitan Government-Seoul National University, South Korea; Department of Otorhinolaryngology, College of Medicine, Seoul National University, Seoul, South Korea
| | - Min-Hyun Park
- Department of Otorhinolaryngology-Head and Neck Surgery, Boramae Medical Center, Seoul Metropolitan Government-Seoul National University, South Korea; Department of Otorhinolaryngology, College of Medicine, Seoul National University, Seoul, South Korea.
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16
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Mapping of neuron soma size as an effective approach to delineate differences between neural populations. J Neurosci Methods 2018; 304:126-135. [PMID: 29715481 DOI: 10.1016/j.jneumeth.2018.04.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/16/2018] [Accepted: 04/27/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND A single histological marker applied to a slice of tissue often reveals myriad cytoarchitectonic characteristics that can obscure differences between neuron populations targeted for study. Isolation and measurement of a single feature from the tissue is possible through a variety of approaches, however, visualizing the data numerically or through graphs alone can preclude being able to identify important features and effects that are not obvious from direct observation of the tissue. NEW METHOD We demonstrate an efficient, effective, and robust approach to quantify and visualize cytoarchitectural features in histologically prepared brain sections. We demonstrate that this approach is able to reveal small differences between populations of neurons that might otherwise have gone undiscovered. RESULTS & COMPARISON WITH EXISTING METHOD(S) We used stereological methods to record the cross-sectional soma area and in situ position of neurons within sections of the cat, monkey, and human visual system. The two-dimensional coordinate of every measured cell was used to produce a scatter plot that recapitulated the natural spatial distribution of cells, and each point in the plot was color-coded according to its respective soma area. The final graphic display was a multi-dimensional map of neuron soma size that revealed subtle differences across neuron aggregations, permitted delineation of regional boundaries, and identified small differences between populations of neurons modified by a period of sensory deprivation. CONCLUSIONS This approach to collecting and displaying cytoarchitectonic data is simple, efficient, and provides a means of investigating small differences between neuron populations.
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Modified Origins of Cortical Projections to the Superior Colliculus in the Deaf: Dispersion of Auditory Efferents. J Neurosci 2018; 38:4048-4058. [PMID: 29610441 DOI: 10.1523/jneurosci.2858-17.2018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 03/13/2018] [Accepted: 03/16/2018] [Indexed: 11/21/2022] Open
Abstract
Following the loss of a sensory modality, such as deafness or blindness, crossmodal plasticity is commonly identified in regions of the cerebrum that normally process the deprived modality. It has been hypothesized that significant changes in the patterns of cortical afferent and efferent projections may underlie these functional crossmodal changes. However, studies of thalamocortical and corticocortical connections have refuted this hypothesis, instead revealing a profound resilience of cortical afferent projections following deafness and blindness. This report is the first study of cortical outputs following sensory deprivation, characterizing cortical projections to the superior colliculus in mature cats (N = 5, 3 female) with perinatal-onset deafness. The superior colliculus was exposed to a retrograde pathway tracer, and subsequently labeled cells throughout the cerebrum were identified and quantified. Overall, the percentage of cortical projections arising from auditory cortex was substantially increased, not decreased, in early-deaf cats compared with intact animals. Furthermore, the distribution of labeled cortical neurons was no longer localized to a particular cortical subregion of auditory cortex but dispersed across auditory cortical regions. Collectively, these results demonstrate that, although patterns of cortical afferents are stable following perinatal deafness, the patterns of cortical efferents to the superior colliculus are highly mutable.SIGNIFICANCE STATEMENT When a sense is lost, the remaining senses are functionally enhanced through compensatory crossmodal plasticity. In deafness, brain regions that normally process sound contribute to enhanced visual and somatosensory perception. We demonstrate that hearing loss alters connectivity between sensory cortex and the superior colliculus, a midbrain region that integrates sensory representations to guide orientation behavior. Contrasting expectation, the proportion of projections from auditory cortex increased in deaf animals compared with normal hearing, with a broad distribution across auditory fields. This is the first description of changes in cortical efferents following sensory loss and provides support for models predicting an inability to form a coherent, multisensory percept of the environment following periods of abnormal development.
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Land R, Radecke JO, Kral A. Congenital Deafness Reduces, But Does Not Eliminate Auditory Responsiveness in Cat Extrastriate Visual Cortex. Neuroscience 2018; 375:149-157. [DOI: 10.1016/j.neuroscience.2018.01.065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/25/2018] [Accepted: 01/30/2018] [Indexed: 01/12/2023]
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19
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Berger C, Kühne D, Scheper V, Kral A. Congenital deafness affects deep layers in primary and secondary auditory cortex. J Comp Neurol 2017; 525. [PMID: 28643417 PMCID: PMC5599951 DOI: 10.1002/cne.24267] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Congenital deafness leads to functional deficits in the auditory cortex for which early cochlear implantation can effectively compensate. Most of these deficits have been demonstrated functionally. Furthermore, the majority of previous studies on deafness have involved the primary auditory cortex; knowledge of higher-order areas is limited to effects of cross-modal reorganization. In this study, we compared the cortical cytoarchitecture of four cortical areas in adult hearing and congenitally deaf cats (CDCs): the primary auditory field A1, two secondary auditory fields, namely the dorsal zone and second auditory field (A2); and a reference visual association field (area 7) in the same section stained either using Nissl or SMI-32 antibodies. The general cytoarchitectonic pattern and the area-specific characteristics in the auditory cortex remained unchanged in animals with congenital deafness. Whereas area 7 did not differ between the groups investigated, all auditory fields were slightly thinner in CDCs, this being caused by reduced thickness of layers IV-VI. The study documents that, while the cytoarchitectonic patterns are in general independent of sensory experience, reduced layer thickness is observed in both primary and higher-order auditory fields in layer IV and infragranular layers. The study demonstrates differences in effects of congenital deafness between supragranular and other cortical layers, but similar dystrophic effects in all investigated auditory fields.
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Affiliation(s)
- Christoph Berger
- Institute of AudioNeuroTechnology & Department of Experimental OtologyENT Clinics, School of Medicine, Hannover Medical UniversityHannoverGermany
| | - Daniela Kühne
- Institute of AudioNeuroTechnology & Department of Experimental OtologyENT Clinics, School of Medicine, Hannover Medical UniversityHannoverGermany
| | - Verena Scheper
- Institute of AudioNeuroTechnology & Department of Experimental OtologyENT Clinics, School of Medicine, Hannover Medical UniversityHannoverGermany
| | - Andrej Kral
- Institute of AudioNeuroTechnology & Department of Experimental OtologyENT Clinics, School of Medicine, Hannover Medical UniversityHannoverGermany
- School of Behavioral and Brain SciencesThe University of TexasDallasUSA
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20
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Butler BE, de la Rua A, Ward-Able T, Lomber SG. Cortical and thalamic connectivity to the second auditory cortex of the cat is resilient to the onset of deafness. Brain Struct Funct 2017; 223:819-835. [PMID: 28940055 DOI: 10.1007/s00429-017-1523-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 09/04/2017] [Indexed: 10/18/2022]
Abstract
It has been well established that following sensory loss, cortical areas that would normally be involved in perceiving stimuli in the absent modality are recruited to subserve the remaining senses. Despite this compensatory functional reorganization, there is little evidence to date for any substantial change in the patterns of anatomical connectivity between sensory cortices. However, while many auditory areas are contracted in the deaf, the second auditory cortex (A2) of the cat undergoes a volumetric expansion following hearing loss, suggesting this cortical area may demonstrate a region-specific pattern of structural reorganization. To address this hypothesis, and to complement existing literature on connectivity within auditory cortex, we injected a retrograde neuronal tracer across the breadth and cortical thickness of A2 to provide the first comprehensive quantification of projections from cortical and thalamic auditory and non-auditory regions to the second auditory cortex, and to determine how these patterns are affected by the onset of deafness. Neural projections arising from auditory, visual, somatomotor, and limbic cortices, as well as thalamic nuclei, were compared across normal hearing, early-deaf, and late-deaf animals. The results demonstrate that, despite previously identified changes in A2 volume, the pattern of projections into this cortical region are unaffected by the onset of hearing loss. These results fail to support the idea that crossmodal plasticity reflects changes in the pattern of projections between cortical regions and provides evidence that the pattern of connectivity that supports normal hearing is retained in the deaf brain.
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Affiliation(s)
- Blake E Butler
- Cerebral Systems Laboratory, University of Western Ontario, London, ON, N6A 5C2, Canada. .,Department of Psychology, University of Western Ontario, London, ON, N6A 5C2, Canada. .,Brain and Mind Institute, University of Western Ontario, London, ON, N6A 5B7, Canada. .,National Centre for Audiology, University of Western Ontario, London, ON, N6G 1H1, Canada.
| | - Alexandra de la Rua
- Cerebral Systems Laboratory, University of Western Ontario, London, ON, N6A 5C2, Canada.,Neuroscience Undergraduate Program, University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Taylor Ward-Able
- Cerebral Systems Laboratory, University of Western Ontario, London, ON, N6A 5C2, Canada.,Neuroscience Undergraduate Program, University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Stephen G Lomber
- Cerebral Systems Laboratory, University of Western Ontario, London, ON, N6A 5C2, Canada.,Department of Psychology, University of Western Ontario, London, ON, N6A 5C2, Canada.,Brain and Mind Institute, University of Western Ontario, London, ON, N6A 5B7, Canada.,National Centre for Audiology, University of Western Ontario, London, ON, N6G 1H1, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, London, ON, N6A 5C1, Canada
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21
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Synaptic distribution and plasticity in primary auditory cortex (A1) exhibits laminar and cell-specific changes in the deaf. Hear Res 2017; 353:122-134. [PMID: 28697947 DOI: 10.1016/j.heares.2017.06.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 06/06/2017] [Accepted: 06/13/2017] [Indexed: 12/19/2022]
Abstract
The processing sequence through primary auditory cortex (A1) is impaired by deafness as evidenced by reduced neuronal activation in A1 of cochlear-implanted deaf cats. Such a loss of neuronal excitation should be manifest as changes in excitatory synaptic number and/or size, for which the post-synaptic correlate is the dendritic spine. Therefore, the present study sought evidence for this functional disruption using Golgi-Cox/light microscopic techniques that examined spine-bearing neurons and their dendritic spine features across all laminae in A1 of early-deaf (ototoxic lesion <1 month; raised into adulthood >16 months) and hearing cats. Surprisingly, in the early-deaf significant increases in spine density and size were observed in the supragranular layers, while significant reductions in spine density were observed for spiny non-pyramidal, but not pyramidal, neurons in the granular layer. No changes in dendritic spine density consistent with loss of excitatory inputs were seen for infragranular neurons. These results indicate that long-term early-deafness induces plastic changes in the excitatory circuitry of A1 that are laminar and cell-specific. An additional finding was that, unlike the expected abundance of stellate neurons that characterize the granular layer of other primary sensory cortices, pyramidal neurons predominate within layer 4 of A1. Collectively, these observations are important for understanding how neuronal connectional configurations contribute to region-specific processing capabilities in normal brains as well as those with altered sensory experiences.
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22
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Meredith MA, Clemo HR, Lomber SG. Is territorial expansion a mechanism for crossmodal plasticity? Eur J Neurosci 2017; 45:1165-1176. [PMID: 28370755 DOI: 10.1111/ejn.13564] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 02/07/2017] [Accepted: 03/13/2017] [Indexed: 01/08/2023]
Abstract
Crossmodal plasticity is the phenomenon whereby, following sensory damage or deprivation, the lost sensory function of a brain region is replaced by one of the remaining senses. One of several proposed mechanisms for this phenomenon involves the expansion of a more active brain region at the expense of another whose sensory inputs have been damaged or lost. This territorial expansion hypothesis was examined in the present study. The cat ectosylvian visual area (AEV) borders the auditory field of the anterior ectosylvian sulcus (FAES), which becomes visually reorganized in the early deaf. If this crossmodal effect in the FAES is due to the expansion of the adjoining AEV into the territory of the FAES after hearing loss, then the reorganized FAES should exhibit connectional features characteristic of the AEV. However, tracer injections revealed significantly different patterns of cortical connectivity between the AEV and the early deaf FAES, and substantial cytoarchitectonic and behavioral distinctions occur as well. Therefore, the crossmodal reorganization of the FAES cannot be mechanistically attributed to the expansion of the adjoining cortical territory of the AEV and an overwhelming number of recent studies now support unmasking of existing connections as the operative mechanism underlying crossmodal plasticity.
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Affiliation(s)
- M A Meredith
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, 1101 E. Marshall St., Sanger Hall Rm. 12-067, Richmond, VA, 23298, USA
| | - H R Clemo
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, 1101 E. Marshall St., Sanger Hall Rm. 12-067, Richmond, VA, 23298, USA
| | - S G Lomber
- Departments of Physiology and Pharmacology, & Psychology, University of Western Ontario, London, ON, Canada
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23
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Abstract
The principles that guide large-scale cortical reorganization remain unclear. In the blind, several visual regions preserve their task specificity; ventral visual areas, for example, become engaged in auditory and tactile object-recognition tasks. It remains open whether task-specific reorganization is unique to the visual cortex or, alternatively, whether this kind of plasticity is a general principle applying to other cortical areas. Auditory areas can become recruited for visual and tactile input in the deaf. Although nonhuman data suggest that this reorganization might be task specific, human evidence has been lacking. Here we enrolled 15 deaf and 15 hearing adults into an functional MRI experiment during which they discriminated between temporally complex sequences of stimuli (rhythms). Both deaf and hearing subjects performed the task visually, in the central visual field. In addition, hearing subjects performed the same task in the auditory modality. We found that the visual task robustly activated the auditory cortex in deaf subjects, peaking in the posterior-lateral part of high-level auditory areas. This activation pattern was strikingly similar to the pattern found in hearing subjects performing the auditory version of the task. Although performing the visual task in deaf subjects induced an increase in functional connectivity between the auditory cortex and the dorsal visual cortex, no such effect was found in hearing subjects. We conclude that in deaf humans the high-level auditory cortex switches its input modality from sound to vision but preserves its task-specific activation pattern independent of input modality. Task-specific reorganization thus might be a general principle that guides cortical plasticity in the brain.
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24
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Kral A, Yusuf PA, Land R. Higher-order auditory areas in congenital deafness: Top-down interactions and corticocortical decoupling. Hear Res 2017; 343:50-63. [DOI: 10.1016/j.heares.2016.08.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 07/25/2016] [Accepted: 08/29/2016] [Indexed: 11/16/2022]
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25
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Park MH, Jang JH, Song JJ, Lee HS, Oh SH. Neurofilament heavy chain expression and neuroplasticity in rat auditory cortex after unilateral and bilateral deafness. Hear Res 2016; 339:155-60. [PMID: 27457532 DOI: 10.1016/j.heares.2016.07.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 07/16/2016] [Accepted: 07/19/2016] [Indexed: 01/24/2023]
Abstract
Deafness induces many plastic changes in the auditory neural system. For instance, dendritic changes cause synaptic changes in neural cells. SMI-32, a monoclonal antibody reveals auditory areas and recognizes non-phosphorylated epitopes on medium- and high-molecular-weight subunits of neurofilament proteins in cortical pyramidal neuron dendrites. We investigated SMI-32-immunoreactive (-ir) protein levels in the auditory cortices of rats with induced unilateral and bilateral deafness. Adult male Sprague-Dawley rats were divided into unilateral deafness (UD), bilateral deafness (BD), and control groups. Deafness was induced by cochlear ablation. All rats were sacrificed, and the auditory cortices were harvested for real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analyses at 2, 4, 6, and 12 weeks after deafness was induced. Immunohistochemical staining was performed to evaluate the location of SMI-32-ir neurons. Neurofilament heavy chain (NEFH) mRNA expression and SMI-32-ir protein levels were increased in the BD group. In particular, SMI-32-ir protein levels increased significantly 6 and 12 weeks after deafness was induced. In contrast, no significant changes in protein level were detected in the right or left auditory cortices at any time point in the UD group. NEFH mRNA level decreased at 4 weeks after deafness was induced in the UD group, but recovered thereafter. Taken together, BD induced plastic changes in the auditory cortex, whereas UD did not affect the auditory neural system sufficiently to show plastic changes, as measured by neurofilament protein level.
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Affiliation(s)
- Min-Hyun Park
- Department of Otorhinolaryngology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, 07061, Boramae Road 5 Gil 20, Dongjak-gu, Seoul, South Korea.
| | - Jeong Hun Jang
- Department of Otorhinolaryngology Head and Neck Surgery, Ajou University Hospital, 16499, World cup-ro 164, Yeongtong-gu, Suwon, Gyeonggi-do, South Korea
| | - Jae-Jin Song
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, 13620, Gumi-Ro 173 Beon-Gil 82, Bundang-gu, Gyeonggi-Do, South Korea
| | - Ho Sun Lee
- Department of Otorhinolaryngology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, 07061, Boramae Road 5 Gil 20, Dongjak-gu, Seoul, South Korea
| | - Seung Ha Oh
- Department of Otorhinolaryngology, College of Medicine, Seoul National University, 03080, Daehangno 101, Jongno-gu, Seoul, South Korea
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Cui C, Ye X, Chopp M, Venkat P, Zacharek A, Yan T, Ning R, Yu P, Cui G, Chen J. miR-145 Regulates Diabetes-Bone Marrow Stromal Cell-Induced Neurorestorative Effects in Diabetes Stroke Rats. Stem Cells Transl Med 2016; 5:1656-1667. [PMID: 27460851 PMCID: PMC5189645 DOI: 10.5966/sctm.2015-0349] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 05/13/2016] [Indexed: 01/08/2023] Open
Abstract
In rats with type 1 diabetes mellitus (T1DM) subject to stroke, the therapeutic effects and underlying mechanisms of action of bone-marrow stromal cells (BMSCs) derived from T1DM rats (DM-BMSCs) and BMSCs derived from normal rats (Nor-BMSCs) were compared. In vitro and in vivo, DM-BMSCs exhibited decreased miR-145 expression. In T1DM rats, DM-BMSC treatment significantly improved functional outcome and increased vascular and white matter remodeling. However, overexpression of miR-145 in DM-BMSCs attenuates DM-BMSC-induced neurorestorative effects in T1DM stroke rats. In rats with type 1 diabetes (T1DM), the therapeutic effects and underlying mechanisms of action of stroke treatment were compared between bone-marrow stromal cells (BMSCs) derived from T1DM rats (DM-BMSCs) and BMSCs derived from normal rats (Nor-BMSCs). The novel role of microRNA-145 (miR-145) in mediating DM-BMSC treatment-induced benefits was also investigated. T1DM rats (n = 8 per group) underwent 2 hours of middle cerebral artery occlusion (MCAo) and were treated 24 hours later with the one of the following (5 × 106 cells administered i.v.): (a) phosphate-buffered saline (PBS); (b) Nor-BMSCs; (c) DM-BMSCs; (d) DM-BMSCs with miR-145 overexpression (miR-145+/+DM-BMSCs); or (e) Nor-BMSCs with miR-145 knockdown. Evaluation of functional outcome, vascular and white-matter remodeling and microRNA expression was made, and in vitro studies were performed. In vitro, DM-BMSCs exhibited decreased miR-145 expression and increased survival compared with Nor-BMSCs. Capillary tube formation and axonal outgrowth in cultured primary cortical neurons were significantly increased by DM-BMSC-conditioned medium compared with Nor-BMSCs, and significantly decreased by miR-145+/+DM-BMSC-conditioned medium compared with DM-BMSCs. In T1DM rats in which stroke had been induced (T1DM stroke rats), DM-BMSC treatment significantly improved functional outcome, increased vascular and white matter remodeling, decreased serum miR-145 expression, and increased expression of the miR-145 target genes adenosine triphosphate-binding cassette transporter 1 (ABCA1) and insulin-like growth factor 1 receptor (IGFR1), compared with Nor-BMSCs or PBS treatment. However, miR-145+/+DM-BMSCs significantly increased serum miR-145 expression and decreased brain ABCA1 and IGFR1 expression, as well as attenuated DM-BMSC-induced neurorestorative effects in T1DM-MCAo rats. DM-BMSCs exhibited decreased miR-145 expression. In T1DM-MCAo rats, DM-BMSC treatment improved functional outcome and promoted neurorestorative effects. The miR-145/ABCA1/IGFR1 pathway may contribute to the enhanced DM-BMSCs’ functional and neurorestorative effects in T1DM stroke rats. Significance In rats with type 1 diabetes (T1DM), the therapeutic effects and underlying mechanisms of action of stroke treatment were compared between bone-marrow stromal cells (BMSCs) derived from T1DM rats (DM-BMSCs) and BMSCs derived from normal rats (Nor-BMSCs). In vitro, DM-BMSCs and derived exosomes decreased miR-145 expression and increased DM-BMSC survival, capillary tube formation, and axonal outgrowth, compared with Nor-BMSCs; these effects were decreased by DM-BMSCs in which miR-145 was overexpressed. In vivo, compared with Nor-BMSC or phosphate-buffered saline treatment, DM-BMSC treatment improved functional outcome and vascular and white matter remodeling, decreased serum miR-145 expression, and increased expression of the miR-145 target genes ABCA1 and IGFR1. microRNA-145 mediated the benefits induced by DM-BMSC treatment.
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Affiliation(s)
- Chengcheng Cui
- Department of Neurology, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, People's Republic of China
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Xinchun Ye
- Department of Neurology, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, People's Republic of China
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
- Department of Physics, Oakland University, Rochester, Michigan, USA
| | - Poornima Venkat
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
- Department of Physics, Oakland University, Rochester, Michigan, USA
| | - Alex Zacharek
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Tao Yan
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Ruizhou Ning
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Peng Yu
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Guiyun Cui
- Department of Neurology, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, People's Republic of China
| | - Jieli Chen
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
- Department of Geriatrics, Tianjin Geriatrics Institute, Tianjin Medical University General Hospital, Tianjin, People's Republic of China
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27
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Crossmodal plasticity in auditory, visual and multisensory cortical areas following noise-induced hearing loss in adulthood. Hear Res 2016; 343:92-107. [PMID: 27387138 DOI: 10.1016/j.heares.2016.06.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Revised: 06/21/2016] [Accepted: 06/27/2016] [Indexed: 11/21/2022]
Abstract
Complete or partial hearing loss results in an increased responsiveness of neurons in the core auditory cortex of numerous species to visual and/or tactile stimuli (i.e., crossmodal plasticity). At present, however, it remains uncertain how adult-onset partial hearing loss affects higher-order cortical areas that normally integrate audiovisual information. To that end, extracellular electrophysiological recordings were performed under anesthesia in noise-exposed rats two weeks post-exposure (0.8-20 kHz at 120 dB SPL for 2 h) and age-matched controls to characterize the nature and extent of crossmodal plasticity in the dorsal auditory cortex (AuD), an area outside of the auditory core, as well as in the neighboring lateral extrastriate visual cortex (V2L), an area known to contribute to audiovisual processing. Computer-generated auditory (noise burst), visual (light flash) and combined audiovisual stimuli were delivered, and the associated spiking activity was used to determine the response profile of each neuron sampled (i.e., unisensory, subthreshold multisensory or bimodal). In both the AuD cortex and the multisensory zone of the V2L cortex, the maximum firing rates were unchanged following noise exposure, and there was a relative increase in the proportion of neurons responsive to visual stimuli, with a concomitant decrease in the number of neurons that were solely responsive to auditory stimuli despite adjusting the sound intensity to account for each rat's hearing threshold. These neighboring cortical areas differed, however, in how noise-induced hearing loss affected audiovisual processing; the total proportion of multisensory neurons significantly decreased in the V2L cortex (control 38.8 ± 3.3% vs. noise-exposed 27.1 ± 3.4%), and dramatically increased in the AuD cortex (control 23.9 ± 3.3% vs. noise-exposed 49.8 ± 6.1%). Thus, following noise exposure, the cortical area showing the greatest relative degree of multisensory convergence transitioned ventrally, away from the audiovisual area, V2L, toward the predominantly auditory area, AuD. Overall, the collective findings of the present study support the suggestion that crossmodal plasticity induced by adult-onset hearing impairment manifests in higher-order cortical areas as a transition in the functional border of the audiovisual cortex.
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Butler BE, Chabot N, Kral A, Lomber SG. Origins of thalamic and cortical projections to the posterior auditory field in congenitally deaf cats. Hear Res 2016; 343:118-127. [PMID: 27306930 DOI: 10.1016/j.heares.2016.06.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 05/27/2016] [Accepted: 06/06/2016] [Indexed: 02/05/2023]
Abstract
Crossmodal plasticity takes place following sensory loss, such that areas that normally process the missing modality are reorganized to provide compensatory function in the remaining sensory systems. For example, congenitally deaf cats outperform normal hearing animals on localization of visual stimuli presented in the periphery, and this advantage has been shown to be mediated by the posterior auditory field (PAF). In order to determine the nature of the anatomical differences that underlie this phenomenon, we injected a retrograde tracer into PAF of congenitally deaf animals and quantified the thalamic and cortical projections to this field. The pattern of projections from areas throughout the brain was determined to be qualitatively similar to that previously demonstrated in normal hearing animals, but with twice as many projections arising from non-auditory cortical areas. In addition, small ectopic projections were observed from a number of fields in visual cortex, including areas 19, 20a, 20b, and 21b, and area 7 of parietal cortex. These areas did not show projections to PAF in cats deafened ototoxically near the onset of hearing, and provide a possible mechanism for crossmodal reorganization of PAF. These, along with the possible contributions of other mechanisms, are considered.
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Affiliation(s)
- Blake E Butler
- Department of Physiology and Pharmacology, University of Western Ontario, Canada; Brain and Mind Institute, University of Western Ontario, Canada.
| | - Nicole Chabot
- Department of Physiology and Pharmacology, University of Western Ontario, Canada; Brain and Mind Institute, University of Western Ontario, Canada
| | - Andrej Kral
- Department of Experimental Otology, Medical University Hannover, Germany; AudioNeuroTechnology, Medical University Hannover, Germany
| | - Stephen G Lomber
- Department of Physiology and Pharmacology, University of Western Ontario, Canada; Department of Psychology, University of Western Ontario, Canada; Brain and Mind Institute, University of Western Ontario, Canada; National Centre for Audiology, University of Western Ontario, Canada
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Butler BE, Chabot N, Lomber SG. Quantifying and comparing the pattern of thalamic and cortical projections to the posterior auditory field in hearing and deaf cats. J Comp Neurol 2016; 524:3042-63. [DOI: 10.1002/cne.24005] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 03/21/2016] [Accepted: 03/24/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Blake E. Butler
- Cerebral Systems Laboratory; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario Canada N6A 5C1
- Brain and Mind Institute; University of Western Ontario; London Ontario Canada N6A 5B7
| | - Nicole Chabot
- Cerebral Systems Laboratory; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario Canada N6A 5C1
- Brain and Mind Institute; University of Western Ontario; London Ontario Canada N6A 5B7
| | - Stephen G. Lomber
- Cerebral Systems Laboratory; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario Canada N6A 5C1
- Department of Psychology; University of Western Ontario; London Ontario Canada N6A 5C2
- Brain and Mind Institute; University of Western Ontario; London Ontario Canada N6A 5B7
- National Centre for Audiology; University of Western Ontario; London Ontario Canada N6G 1H1
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30
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Early-onset hearing loss reorganizes the visual and auditory network in children without cochlear implantation. Neuroreport 2016; 27:197-202. [DOI: 10.1097/wnr.0000000000000524] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Shiell MM, Champoux F, Zatorre RJ. The Right Hemisphere Planum Temporale Supports Enhanced Visual Motion Detection Ability in Deaf People: Evidence from Cortical Thickness. Neural Plast 2016; 2016:7217630. [PMID: 26885405 PMCID: PMC4738967 DOI: 10.1155/2016/7217630] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 11/16/2015] [Accepted: 11/18/2015] [Indexed: 11/18/2022] Open
Abstract
After sensory loss, the deprived cortex can reorganize to process information from the remaining modalities, a phenomenon known as cross-modal reorganization. In blind people this cross-modal processing supports compensatory behavioural enhancements in the nondeprived modalities. Deaf people also show some compensatory visual enhancements, but a direct relationship between these abilities and cross-modally reorganized auditory cortex has only been established in an animal model, the congenitally deaf cat, and not in humans. Using T1-weighted magnetic resonance imaging, we measured cortical thickness in the planum temporale, Heschl's gyrus and sulcus, the middle temporal area MT+, and the calcarine sulcus, in early-deaf persons. We tested for a correlation between this measure and visual motion detection thresholds, a visual function where deaf people show enhancements as compared to hearing. We found that the cortical thickness of a region in the right hemisphere planum temporale, typically an auditory region, was greater in deaf individuals with better visual motion detection thresholds. This same region has previously been implicated in functional imaging studies as important for functional reorganization. The structure-behaviour correlation observed here demonstrates this area's involvement in compensatory vision and indicates an anatomical correlate, increased cortical thickness, of cross-modal plasticity.
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Affiliation(s)
- Martha M. Shiell
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada H3A 2B4
- International Laboratory for Brain, Music, and Sound Research (BRAMS), Montreal, QC, Canada H2V 4P3
- Centre for Research on Brain, Language, and Music (CRBLM), Montreal, QC, Canada H3G 2A8
| | - François Champoux
- International Laboratory for Brain, Music, and Sound Research (BRAMS), Montreal, QC, Canada H2V 4P3
- Centre for Research on Brain, Language, and Music (CRBLM), Montreal, QC, Canada H3G 2A8
- École d'Orthophonie et d'Audiologie, Université de Montréal, Montreal, QC, Canada H3N 1X7
- Centre de Recherche Interdisciplinaire en Réadaptation du Montréal Métropolitain, Institut Raymond-Dewar, Montreal, QC, Canada H2L 4G9
| | - Robert J. Zatorre
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada H3A 2B4
- International Laboratory for Brain, Music, and Sound Research (BRAMS), Montreal, QC, Canada H2V 4P3
- Centre for Research on Brain, Language, and Music (CRBLM), Montreal, QC, Canada H3G 2A8
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32
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Meredith MA, Clemo HR, Corley SB, Chabot N, Lomber SG. Cortical and thalamic connectivity of the auditory anterior ectosylvian cortex of early-deaf cats: Implications for neural mechanisms of crossmodal plasticity. Hear Res 2015; 333:25-36. [PMID: 26724756 DOI: 10.1016/j.heares.2015.12.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 11/23/2015] [Accepted: 12/01/2015] [Indexed: 01/31/2023]
Abstract
Early hearing loss leads to crossmodal plasticity in regions of the cerebrum that are dominated by acoustical processing in hearing subjects. Until recently, little has been known of the connectional basis of this phenomenon. One region whose crossmodal properties are well-established is the auditory field of the anterior ectosylvian sulcus (FAES) in the cat, where neurons are normally responsive to acoustic stimulation and its deactivation leads to the behavioral loss of accurate orienting toward auditory stimuli. However, in early-deaf cats, visual responsiveness predominates in the FAES and its deactivation blocks accurate orienting behavior toward visual stimuli. For such crossmodal reorganization to occur, it has been presumed that novel inputs or increased projections from non-auditory cortical areas must be generated, or that existing non-auditory connections were 'unmasked.' These possibilities were tested using tracer injections into the FAES of adult cats deafened early in life (and hearing controls), followed by light microscopy to localize retrogradely labeled neurons. Surprisingly, the distribution of cortical and thalamic afferents to the FAES was very similar among early-deaf and hearing animals. No new visual projection sources were identified and visual cortical connections to the FAES were comparable in projection proportions. These results support an alternate theory for the connectional basis for cross-modal plasticity that involves enhanced local branching of existing projection terminals that originate in non-auditory as well as auditory cortices.
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Affiliation(s)
- M Alex Meredith
- Virginia Commonwealth University School of Medicine, Department of Anatomy and Neurobiology, Richmond, VA 23298, USA.
| | - H Ruth Clemo
- Virginia Commonwealth University School of Medicine, Department of Anatomy and Neurobiology, Richmond, VA 23298, USA
| | - Sarah B Corley
- Virginia Commonwealth University School of Medicine, Department of Anatomy and Neurobiology, Richmond, VA 23298, USA; University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nicole Chabot
- Cerebral Systems Laboratory, The Brain and Mind Institute, Natural Sciences Centre, University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Stephen G Lomber
- Cerebral Systems Laboratory, The Brain and Mind Institute, Natural Sciences Centre, University of Western Ontario, London, Ontario N6A 5B7, Canada
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Almeida J, He D, Chen Q, Mahon BZ, Zhang F, Gonçalves ÓF, Fang F, Bi Y. Decoding Visual Location From Neural Patterns in the Auditory Cortex of the Congenitally Deaf. Psychol Sci 2015; 26:1771-82. [PMID: 26423461 DOI: 10.1177/0956797615598970] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 07/14/2015] [Indexed: 11/17/2022] Open
Abstract
Sensory cortices of individuals who are congenitally deprived of a sense can exhibit considerable plasticity and be recruited to process information from the senses that remain intact. Here, we explored whether the auditory cortex of congenitally deaf individuals represents visual field location of a stimulus-a dimension that is represented in early visual areas. We used functional MRI to measure neural activity in auditory and visual cortices of congenitally deaf and hearing humans while they observed stimuli typically used for mapping visual field preferences in visual cortex. We found that the location of a visual stimulus can be successfully decoded from the patterns of neural activity in auditory cortex of congenitally deaf but not hearing individuals. This is particularly true for locations within the horizontal plane and within peripheral vision. These data show that the representations stored within neuroplastically changed auditory cortex can align with dimensions that are typically represented in visual cortex.
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Affiliation(s)
- Jorge Almeida
- Faculty of Psychology and Educational Sciences, University of Coimbra Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra
| | - Dongjun He
- Department of Psychology, Peking University Key Laboratory of Machine Perception (Ministry of Education), Peking University
| | - Quanjing Chen
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University IDG/McGovern Institute for Brain Research, Beijing Normal University Department of Brain and Cognitive Sciences, University of Rochester
| | - Bradford Z Mahon
- Department of Brain and Cognitive Sciences, University of Rochester Department of Neurosurgery, University of Rochester Center for Visual Science, University of Rochester
| | - Fan Zhang
- Faculty of Psychology and Educational Sciences, University of Coimbra Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra
| | - Óscar F Gonçalves
- School of Psychology, University of Minho Neuropsychophysiology Laboratory, Research Center in Psychology, School of Psychology, University of Minho Bouvé College of Health Sciences, Northeastern University
| | - Fang Fang
- Department of Psychology, Peking University Key Laboratory of Machine Perception (Ministry of Education), Peking University Peking-Tsinghua Center for Life Sciences, Peking University PKU-IDG/McGovern Institute for Brain Research, Peking University
| | - Yanchao Bi
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University IDG/McGovern Institute for Brain Research, Beijing Normal University
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Cardin V, Smittenaar RC, Orfanidou E, Rönnberg J, Capek CM, Rudner M, Woll B. Differential activity in Heschl's gyrus between deaf and hearing individuals is due to auditory deprivation rather than language modality. Neuroimage 2015; 124:96-106. [PMID: 26348556 DOI: 10.1016/j.neuroimage.2015.08.073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 08/23/2015] [Accepted: 08/24/2015] [Indexed: 10/23/2022] Open
Abstract
Sensory cortices undergo crossmodal reorganisation as a consequence of sensory deprivation. Congenital deafness in humans represents a particular case with respect to other types of sensory deprivation, because cortical reorganisation is not only a consequence of auditory deprivation, but also of language-driven mechanisms. Visual crossmodal plasticity has been found in secondary auditory cortices of deaf individuals, but it is still unclear if reorganisation also takes place in primary auditory areas, and how this relates to language modality and auditory deprivation. Here, we dissociated the effects of language modality and auditory deprivation on crossmodal plasticity in Heschl's gyrus as a whole, and in cytoarchitectonic region Te1.0 (likely to contain the core auditory cortex). Using fMRI, we measured the BOLD response to viewing sign language in congenitally or early deaf individuals with and without sign language knowledge, and in hearing controls. Results show that differences between hearing and deaf individuals are due to a reduction in activation caused by visual stimulation in the hearing group, which is more significant in Te1.0 than in Heschl's gyrus as a whole. Furthermore, differences between deaf and hearing groups are due to auditory deprivation, and there is no evidence that the modality of language used by deaf individuals contributes to crossmodal plasticity in Heschl's gyrus.
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Affiliation(s)
- Velia Cardin
- Deafness, Cognition and Language Research Centre, 49 Gordon Square, University College London, London WC1H 0BT, UK; Linnaeus Centre HEAD, Swedish Institute for Disability Research, Department of Behavioural Sciences and Learning, Linköping University, Sweden.
| | - Rebecca C Smittenaar
- Experimental Psychology, 26 Bedford Way, University College London, London WC1H 0AP, UK
| | - Eleni Orfanidou
- Deafness, Cognition and Language Research Centre, 49 Gordon Square, University College London, London WC1H 0BT, UK; School of Psychology, University of Crete, Greece
| | - Jerker Rönnberg
- Linnaeus Centre HEAD, Swedish Institute for Disability Research, Department of Behavioural Sciences and Learning, Linköping University, Sweden
| | - Cheryl M Capek
- School of Psychological Sciences, University of Manchester, Manchester M13 9PL, UK
| | - Mary Rudner
- Linnaeus Centre HEAD, Swedish Institute for Disability Research, Department of Behavioural Sciences and Learning, Linköping University, Sweden
| | - Bencie Woll
- Deafness, Cognition and Language Research Centre, 49 Gordon Square, University College London, London WC1H 0BT, UK
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35
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Shiell MM, Champoux F, Zatorre RJ. Reorganization of auditory cortex in early-deaf people: functional connectivity and relationship to hearing aid use. J Cogn Neurosci 2015; 27:150-63. [PMID: 25000527 DOI: 10.1162/jocn_a_00683] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Cross-modal reorganization after sensory deprivation is a model for understanding brain plasticity. Although it is a well-documented phenomenon, we still know little of the mechanisms underlying it or the factors that constrain and promote it. Using fMRI, we identified visual motion-related activity in 17 early-deaf and 17 hearing adults. We found that, in the deaf, the posterior superior temporal gyrus (STG) was responsive to visual motion. We compared functional connectivity of this reorganized cortex between groups to identify differences in functional networks associated with reorganization. In the deaf more than the hearing, the STG displayed increased functional connectivity with a region in the calcarine fissure. We also explored the role of hearing aid use, a factor that may contribute to variability in cross-modal reorganization. We found that both the cross-modal activity in STG and the functional connectivity between STG and calcarine cortex correlated with duration of hearing aid use, supporting the hypothesis that residual hearing affects cross-modal reorganization. We conclude that early auditory deprivation alters not only the organization of auditory regions but also the interactions between auditory and primary visual cortex and that auditory input, as indexed by hearing aid use, may inhibit cross-modal reorganization in early-deaf people.
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36
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High-field fMRI reveals tonotopically-organized and core auditory cortex in the cat. Hear Res 2015; 325:1-11. [DOI: 10.1016/j.heares.2015.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/26/2015] [Accepted: 03/05/2015] [Indexed: 01/12/2023]
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Chabot N, Butler BE, Lomber SG. Differential modification of cortical and thalamic projections to cat primary auditory cortex following early- and late-onset deafness. J Comp Neurol 2015; 523:2297-320. [DOI: 10.1002/cne.23790] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Nicole Chabot
- Cerebral Systems Laboratory; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario Canada N6A 5C1
- Brain and Mind Institute, University of Western Ontario; London Ontario Canada N6A 5B7
| | - Blake E. Butler
- Cerebral Systems Laboratory; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario Canada N6A 5C1
- Brain and Mind Institute, University of Western Ontario; London Ontario Canada N6A 5B7
| | - Stephen G. Lomber
- Cerebral Systems Laboratory; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Psychology; University of Western Ontario; London Ontario Canada N6A 5C2
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario Canada N6A 5C1
- Brain and Mind Institute, University of Western Ontario; London Ontario Canada N6A 5B7
- National Centre for Audiology; University of Western Ontario; London Ontario Canada N6A 1H1
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38
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Wong C, Chabot N, Kok MA, Lomber SG. Amplified somatosensory and visual cortical projections to a core auditory area, the anterior auditory field, following early- and late-onset deafness. J Comp Neurol 2015; 523:1925-47. [DOI: 10.1002/cne.23771] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 02/25/2015] [Accepted: 02/26/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Carmen Wong
- Cerebral Systems Laboratory, University of Western Ontario; London Ontario N6A 5K8 Canada
- Graduate Program in Neuroscience; University of Western Ontario; London Ontario N6A 5K8 Canada
| | - Nicole Chabot
- Cerebral Systems Laboratory, University of Western Ontario; London Ontario N6A 5K8 Canada
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario N6A 5K8 Canada
| | - Melanie A. Kok
- Cerebral Systems Laboratory, University of Western Ontario; London Ontario N6A 5K8 Canada
- Graduate Program in Neuroscience; University of Western Ontario; London Ontario N6A 5K8 Canada
| | - Stephen G. Lomber
- Cerebral Systems Laboratory, University of Western Ontario; London Ontario N6A 5K8 Canada
- Department of Physiology and Pharmacology; University of Western Ontario; London Ontario N6A 5K8 Canada
- Department of Psychology; University of Western Ontario; London Ontario N6A 5K8 Canada
- Brain and Mind Institute, University of Western Ontario; London Ontario N6A 5K8 Canada
- National Centre for Audiology, University of Western Ontario; London Ontario N6A 5K8 Canada
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Clemo HR, Lomber SG, Meredith MA. Synaptic Basis for Cross-modal Plasticity: Enhanced Supragranular Dendritic Spine Density in Anterior Ectosylvian Auditory Cortex of the Early Deaf Cat. Cereb Cortex 2014; 26:1365-76. [PMID: 25274986 DOI: 10.1093/cercor/bhu225] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In the cat, the auditory field of the anterior ectosylvian sulcus (FAES) is sensitive to auditory cues and its deactivation leads to orienting deficits toward acoustic, but not visual, stimuli. However, in early deaf cats, FAES activity shifts to the visual modality and its deactivation blocks orienting toward visual stimuli. Thus, as in other auditory cortices, hearing loss leads to cross-modal plasticity in the FAES. However, the synaptic basis for cross-modal plasticity is unknown. Therefore, the present study examined the effect of early deafness on the density, distribution, and size of dendritic spines in the FAES. Young cats were ototoxically deafened and raised until adulthood when they (and hearing controls) were euthanized, the cortex stained using Golgi-Cox, and FAES neurons examined using light microscopy. FAES dendritic spine density averaged 0.85 spines/μm in hearing animals, but was significantly higher (0.95 spines/μm) in the early deaf. Size distributions and increased spine density were evident specifically on apical dendrites of supragranular neurons. In separate tracer experiments, cross-modal cortical projections were shown to terminate predominantly within the supragranular layers of the FAES. This distributional correspondence between projection terminals and dendritic spine changes indicates that cross-modal plasticity is synaptically based within the supragranular layers of the early deaf FAES.
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Affiliation(s)
- H Ruth Clemo
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298-0709, USA
| | - Stephen G Lomber
- Brain and Mind Institute, National Centre for Audiology, University of Western Ontario, London, ON, Canada
| | - M Alex Meredith
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298-0709, USA
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Stettler O, Moya KL. Distinct roles of homeoproteins in brain topographic mapping and in neural circuit formation. Semin Cell Dev Biol 2014; 35:165-72. [PMID: 25042849 DOI: 10.1016/j.semcdb.2014.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 01/02/2023]
Abstract
The construction of the brain is a highly regulated process, requiring coordination of various cellular and molecular mechanisms that together ensure the stability of the cerebrum architecture and functions. The mature brain is an organ that performs complex computational operations using specific sensory information from the outside world and this requires precise organization within sensory networks and a separation of sensory modalities during development. We review here the role of homeoproteins in the arealization of the brain according to sensorimotor functions, the micropartition of its cytoarchitecture, and the maturation of its sensory circuitry. One of the most interesting observation about homeoproteins in recent years concerns their ability to act both in a cell-autonomous and non-cell-autonomous manner. The highlights in the present review collectively show how these two modes of action of homeoproteins confer various functions in shaping cortical maps.
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Affiliation(s)
- Olivier Stettler
- Laboratoire CRRET EAC 7149, Université Paris-Est Créteil, 61, Av. du Général de Gaulle, 94010 Créteil Cedex, France.
| | - Kenneth L Moya
- Collège de France, Center for Interdisciplinary Research in Biology, UMR CNRS 7241/INSERM U1050, 11 place Marcelin Berthelot, 75005 Paris, France; Labex Memolife, PSL Research University, France
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41
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Butler BE, Lomber SG. Functional and structural changes throughout the auditory system following congenital and early-onset deafness: implications for hearing restoration. Front Syst Neurosci 2013; 7:92. [PMID: 24324409 PMCID: PMC3840613 DOI: 10.3389/fnsys.2013.00092] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 11/03/2013] [Indexed: 11/23/2022] Open
Abstract
The absence of auditory input, particularly during development, causes widespread changes in the structure and function of the auditory system, extending from peripheral structures into auditory cortex. In humans, the consequences of these changes are far-reaching and often include detriments to language acquisition, and associated psychosocial issues. Much of what is currently known about the nature of deafness-related changes to auditory structures comes from studies of congenitally deaf or early-deafened animal models. Fortunately, the mammalian auditory system shows a high degree of preservation among species, allowing for generalization from these models to the human auditory system. This review begins with a comparison of common methods used to obtain deaf animal models, highlighting the specific advantages and anatomical consequences of each. Some consideration is also given to the effectiveness of methods used to measure hearing loss during and following deafening procedures. The structural and functional consequences of congenital and early-onset deafness have been examined across a variety of mammals. This review attempts to summarize these changes, which often involve alteration of hair cells and supporting cells in the cochleae, and anatomical and physiological changes that extend through subcortical structures and into cortex. The nature of these changes is discussed, and the impacts to neural processing are addressed. Finally, long-term changes in cortical structures are discussed, with a focus on the presence or absence of cross-modal plasticity. In addition to being of interest to our understanding of multisensory processing, these changes also have important implications for the use of assistive devices such as cochlear implants.
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Affiliation(s)
- Blake E. Butler
- Cerebral Systems Laboratory, Department of Physiology and Pharmacology, Brain and Mind Institute, University of Western OntarioLondon, ON, Canada
| | - Stephen G. Lomber
- Cerebral Systems Laboratory, Department of Physiology and Pharmacology and Department of Psychology, National Centre for Audiology, Brain and Mind Institute, University of Western OntarioLondon, ON, Canada
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