The Experts below are selected from a list of 7185 Experts worldwide ranked by ideXlab platform
Michael A Muniak - One of the best experts on this subject based on the ideXlab platform.
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Tonotopic Organization of Vertical Cells in the Dorsal Cochlear Nucleus of the CBA/J Mouse
2020Co-Authors: Michael A Muniak, David K RyugoAbstract:ABSTRACT The systematic and Topographic Representation of frequency is a first principle of organization throughout the auditory system. The dorsal cochlear nucleus (DCN) receives direct tonotopic projections from the auditory nerve (AN) as well as secondary and descending projections from other sources
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tonotopic organization of vertical cells in the dorsal cochlear nucleus of the cba j mouse
The Journal of Comparative Neurology, 2014Co-Authors: Michael A Muniak, David K RyugoAbstract:The systematic and Topographic Representation of frequency is a first principle of organization throughout the auditory system. The dorsal cochlear nucleus (DCN) receives direct tonotopic projections from the auditory nerve (AN) as well as secondary and descending projections from other sources. Among the recipients of AN input in the DCN are vertical cells (also called tuberculoventral cells), glycinergic interneurons thought to provide on- or near-best-frequency feed-forward inhibition to principal cells in the DCN and various cells in the anteroventral cochlear nucleus (AVCN). Differing lines of physiological and anatomical evidence suggest that vertical cells and their projections are organized with respect to frequency, but this has not been conclusively demonstrated in the intact mammalian brain. To address this issue, we retrogradely labeled vertical cells via physiologically targeted injections in the AVCN of the CBA/J mouse. Results from multiple cases were merged with a normalized 3D template of the cochlear nucleus (Muniak et al. [2013] J. Comp. Neurol. 521:1510–1532) to demonstrate quantitatively that the arrangement of vertical cells is tonotopic and aligned to the innervation pattern of the AN. These results suggest that vertical cells are well positioned for providing immediate, frequency-specific inhibition onto cells of the DCN and AVCN to facilitate spectral processing. J. Comp. Neurol. 522:937–949, 2014. © 2013 Wiley Periodicals, Inc.
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tonotopic organization of vertical cells in the dorsal cochlear nucleus of the cba j mouse
The Journal of Comparative Neurology, 2014Co-Authors: Michael A Muniak, David K RyugoAbstract:The systematic and Topographic Representation of frequency is a first principle of organization throughout the auditory system. The dorsal cochlear nucleus (DCN) receives direct tonotopic projections from the auditory nerve (AN) as well as secondary and descending projections from other sources. Among the recipients of AN input in the DCN are vertical cells (also called tuberculoventral cells), glycinergic interneurons thought to provide on- or near-best-frequency feed-forward inhibition to principal cells in the DCN and various cells in the anteroventral cochlear nucleus (AVCN). Differing lines of physiological and anatomical evidence suggest that vertical cells and their projections are organized with respect to frequency, but this has not been conclusively demonstrated in the intact mammalian brain. To address this issue, we retrogradely labeled vertical cells via physiologically targeted injections in the AVCN of the CBA/J mouse. Results from multiple cases were merged with a normalized 3D template of the cochlear nucleus (Muniak et al. [2013] J. Comp. Neurol. 521:1510-1532) to demonstrate quantitatively that the arrangement of vertical cells is tonotopic and aligned to the innervation pattern of the AN. These results suggest that vertical cells are well positioned for providing immediate, frequency-specific inhibition onto cells of the DCN and AVCN to facilitate spectral processing.
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3d model of frequency Representation in the cochlear nucleus of the cba j mouse
The Journal of Comparative Neurology, 2013Co-Authors: Michael A Muniak, Alejandro Rivas, Karen L Montey, Bradford J May, Howard W Francis, David K RyugoAbstract:The relationship between structure and function is an invaluable context with which to explore biological mechanisms of normal and dysfunctional hearing. The systematic and Topographic Representation of frequency originates at the cochlea, and is retained throughout much of the central auditory system. The cochlear nucleus (CN), which initiates all ascending auditory pathways, represents an essential link for understanding frequency organization. A model of the CN that maps frequency Representation in 3D would facilitate investigations of possible frequency specializations and pathologic changes that disturb frequency organization. Toward this goal, we reconstructed in 3D the trajectories of labeled auditory nerve (AN) fibers following multiunit recordings and dye injections in the anteroventral CN of the CBA/J mouse. We observed that each injection produced a continuous sheet of labeled AN fibers. Individual cases were normalized to a template using 3D alignment procedures that revealed a systematic and tonotopic arrangement of AN fibers in each subdivision with a clear indication of isofrequency laminae. The combined dataset was used to mathematically derive a 3D quantitative map of frequency organization throughout the entire volume of the CN. This model, available online (http://3D.ryugolab.com/), can serve as a tool for quantitatively testing hypotheses concerning frequency and location in the CN.
David K Ryugo - One of the best experts on this subject based on the ideXlab platform.
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Tonotopic Organization of Vertical Cells in the Dorsal Cochlear Nucleus of the CBA/J Mouse
2020Co-Authors: Michael A Muniak, David K RyugoAbstract:ABSTRACT The systematic and Topographic Representation of frequency is a first principle of organization throughout the auditory system. The dorsal cochlear nucleus (DCN) receives direct tonotopic projections from the auditory nerve (AN) as well as secondary and descending projections from other sources
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tonotopic organization of vertical cells in the dorsal cochlear nucleus of the cba j mouse
The Journal of Comparative Neurology, 2014Co-Authors: Michael A Muniak, David K RyugoAbstract:The systematic and Topographic Representation of frequency is a first principle of organization throughout the auditory system. The dorsal cochlear nucleus (DCN) receives direct tonotopic projections from the auditory nerve (AN) as well as secondary and descending projections from other sources. Among the recipients of AN input in the DCN are vertical cells (also called tuberculoventral cells), glycinergic interneurons thought to provide on- or near-best-frequency feed-forward inhibition to principal cells in the DCN and various cells in the anteroventral cochlear nucleus (AVCN). Differing lines of physiological and anatomical evidence suggest that vertical cells and their projections are organized with respect to frequency, but this has not been conclusively demonstrated in the intact mammalian brain. To address this issue, we retrogradely labeled vertical cells via physiologically targeted injections in the AVCN of the CBA/J mouse. Results from multiple cases were merged with a normalized 3D template of the cochlear nucleus (Muniak et al. [2013] J. Comp. Neurol. 521:1510–1532) to demonstrate quantitatively that the arrangement of vertical cells is tonotopic and aligned to the innervation pattern of the AN. These results suggest that vertical cells are well positioned for providing immediate, frequency-specific inhibition onto cells of the DCN and AVCN to facilitate spectral processing. J. Comp. Neurol. 522:937–949, 2014. © 2013 Wiley Periodicals, Inc.
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tonotopic organization of vertical cells in the dorsal cochlear nucleus of the cba j mouse
The Journal of Comparative Neurology, 2014Co-Authors: Michael A Muniak, David K RyugoAbstract:The systematic and Topographic Representation of frequency is a first principle of organization throughout the auditory system. The dorsal cochlear nucleus (DCN) receives direct tonotopic projections from the auditory nerve (AN) as well as secondary and descending projections from other sources. Among the recipients of AN input in the DCN are vertical cells (also called tuberculoventral cells), glycinergic interneurons thought to provide on- or near-best-frequency feed-forward inhibition to principal cells in the DCN and various cells in the anteroventral cochlear nucleus (AVCN). Differing lines of physiological and anatomical evidence suggest that vertical cells and their projections are organized with respect to frequency, but this has not been conclusively demonstrated in the intact mammalian brain. To address this issue, we retrogradely labeled vertical cells via physiologically targeted injections in the AVCN of the CBA/J mouse. Results from multiple cases were merged with a normalized 3D template of the cochlear nucleus (Muniak et al. [2013] J. Comp. Neurol. 521:1510-1532) to demonstrate quantitatively that the arrangement of vertical cells is tonotopic and aligned to the innervation pattern of the AN. These results suggest that vertical cells are well positioned for providing immediate, frequency-specific inhibition onto cells of the DCN and AVCN to facilitate spectral processing.
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3d model of frequency Representation in the cochlear nucleus of the cba j mouse
The Journal of Comparative Neurology, 2013Co-Authors: Michael A Muniak, Alejandro Rivas, Karen L Montey, Bradford J May, Howard W Francis, David K RyugoAbstract:The relationship between structure and function is an invaluable context with which to explore biological mechanisms of normal and dysfunctional hearing. The systematic and Topographic Representation of frequency originates at the cochlea, and is retained throughout much of the central auditory system. The cochlear nucleus (CN), which initiates all ascending auditory pathways, represents an essential link for understanding frequency organization. A model of the CN that maps frequency Representation in 3D would facilitate investigations of possible frequency specializations and pathologic changes that disturb frequency organization. Toward this goal, we reconstructed in 3D the trajectories of labeled auditory nerve (AN) fibers following multiunit recordings and dye injections in the anteroventral CN of the CBA/J mouse. We observed that each injection produced a continuous sheet of labeled AN fibers. Individual cases were normalized to a template using 3D alignment procedures that revealed a systematic and tonotopic arrangement of AN fibers in each subdivision with a clear indication of isofrequency laminae. The combined dataset was used to mathematically derive a 3D quantitative map of frequency organization throughout the entire volume of the CN. This model, available online (http://3D.ryugolab.com/), can serve as a tool for quantitatively testing hypotheses concerning frequency and location in the CN.
M J Keating - One of the best experts on this subject based on the ideXlab platform.
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the developmental emergence of the Representation of auditory azimuth in the external nucleus of the inferior colliculus of the guinea pig the effects of visual and auditory deprivation
Developmental Brain Research, 1995Co-Authors: K E Binns, Deborah J. Withington, M J KeatingAbstract:Abstract A Topographic Representation of the auditory azimuth has been described in the external nucleus of the inferior colliculus (ICX) of the guinea-pig [3]. This Representation is characterized by directional multi-unit responses, at threshold stimulation intensities, with directional preferences organized in such a way as to represent the auditory azimuth along the rostro-caudal axis of the ICX. The following paper considers the emergence of that map and the role of developmental experience in its elaboration. Multi-unit responses to free-field broad-band auditory stimuli were recorded in the ICX. At threshold stimulation intensities, multi-unit receptive fields (MURFs) obtained from younger animals showed the same discrete spatial tuning as found in MURFs from animals older than 35 DAB (days after birth). However, a normal adult Topographic Representation was not present until animals were at least 30–32 DAB. Visual deprivation, by dark-rearing from birth until mapping (at 35–43 DAB), had no obvious detrimental effects on auditory receptive field size or Topographic order in the ICX. Auditory deprivation was achieved by rearing animals in an environment of continuous omnidirectional noise from birth until mapping (47–53 DAB). Following auditory deprivation, receptive fields remained relatively discrete, but no correlation between rostro-caudal position of the recording site and the angle of the best response was observed. Thus, the Representation of auditory azimuth in the ICX appears to be unperturbed by developmental visual deprivation but is susceptible to developmental auditory deprivation.
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a Topographic Representation of auditory space in the external nucleus of the inferior colliculus of the guinea pig
Brain Research, 1992Co-Authors: K E Binns, Deborah J. Withington, Simon Grant, M J KeatingAbstract:Abstract The possibility that the external nucleus of the inferior colliculus (ICX) of the pigmented guinea-pig contains a map of auditory space has been investigated. Auditory stimuli consisted of broad-band sound delivered under free-field anechoic conditions from a range of positions around the animal's azimuthal axis. The responses of clusters of neurons in the ICX to threshold and to near-threshold stimuli displayed sharp spatial tuning. The responses recorded from rostral ICX revealed a preference for auditory stimuli in the anterior field while more caudal neurons preferentially responded to sounds presented in the posterior field. Neurons at intermediate points, along the rostro-caudal axis of the nucleus, displayed preferences for sound stimuli in appropriately intermediate field positions along the contralateral azimuthal axis. At higher stimulus intensities the spatial tuning of the responses decreased, but the optimal direction of preference was usually retained. The contribution of binaural processing to auditory spatial tuning was evident, since unilateral cochlea ablation destroyed the spatial tuning at higher stimulus intensities. The results presented provide the first evidence that a Topographically ordered Representation of the contralateral auditory azimuth is present in the ICX of a mammal.
Nathalie Tzouriomazoyer - One of the best experts on this subject based on the ideXlab platform.
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neural basis of mental scanning of a Topographic Representation built from a text
Cerebral Cortex, 2002Co-Authors: Emmanuel Mellet, S Bricogne, F Crivello, Bernard Mazoyer, Michel Denis, Nathalie TzouriomazoyerAbstract:Humans have the ability to build and to inspect an internal visual image of an environment built from a verbal description. We used positron emission tomography (PET) to investigate the brain areas engaged in the mental scanning of a map that subjects built from the reading of a descriptive text. This task engaged a parieto-frontal network known to deal with spatial Representations. Additional activations were evidenced in the angular gyrus and in Broca’s and Wernicke’s areas. In order to examine the neural impact of the learning modality, these PET results were compared to those obtained in another group of six subjects who performed a similar mental scanning task on a Topographic Representation built from visual inspection of a map. Both scanning tasks engaged the parieto-frontal network. However, the bilateral activation of the angular gyrus as well as the involvement of language areas appeared specific to the mental scanning of the Topographic Representation built from textual information. On the other hand, the right medial temporal lobe was activated only when a map had been visually learned. These results suggest that although both tasks involved visuo-spatial internal Representation, a trace of the learning modality remained present in the brain.
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neural basis of mental scanning of a Topographic Representation built from a text
Cerebral Cortex, 2002Co-Authors: Emmanuel Mellet, S Bricogne, F Crivello, Bernard Mazoyer, Michel Denis, Nathalie TzouriomazoyerAbstract:Humans have the ability to build and to inspect an internal visual image of an environment built from a verbal description. We used positron emission tomography (PET) to investigate the brain areas engaged in the mental scanning of a map that subjects built from the reading of a descriptive text. This task engaged a parieto-frontal network known to deal with spatial Representations. Additional activations were evidenced in the angular gyrus and in Broca’s and Wernicke’s areas. In order to examine the neural impact of the learning modality, these PET results were compared to those obtained in another group of six subjects who performed a similar mental scanning task on a Topographic Representation built from visual inspection of a map. Both scanning tasks engaged the parieto-frontal network. However, the bilateral activation of the angular gyrus as well as the involvement of language areas appeared specific to the mental scanning of the Topographic Representation built from textual information. On the other hand, the right medial temporal lobe was activated only when a map had been visually learned. These results suggest that although both tasks involved visuo-spatial internal Representation, a trace of the learning modality remained present in the brain.
K E Binns - One of the best experts on this subject based on the ideXlab platform.
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the developmental emergence of the Representation of auditory azimuth in the external nucleus of the inferior colliculus of the guinea pig the effects of visual and auditory deprivation
Developmental Brain Research, 1995Co-Authors: K E Binns, Deborah J. Withington, M J KeatingAbstract:Abstract A Topographic Representation of the auditory azimuth has been described in the external nucleus of the inferior colliculus (ICX) of the guinea-pig [3]. This Representation is characterized by directional multi-unit responses, at threshold stimulation intensities, with directional preferences organized in such a way as to represent the auditory azimuth along the rostro-caudal axis of the ICX. The following paper considers the emergence of that map and the role of developmental experience in its elaboration. Multi-unit responses to free-field broad-band auditory stimuli were recorded in the ICX. At threshold stimulation intensities, multi-unit receptive fields (MURFs) obtained from younger animals showed the same discrete spatial tuning as found in MURFs from animals older than 35 DAB (days after birth). However, a normal adult Topographic Representation was not present until animals were at least 30–32 DAB. Visual deprivation, by dark-rearing from birth until mapping (at 35–43 DAB), had no obvious detrimental effects on auditory receptive field size or Topographic order in the ICX. Auditory deprivation was achieved by rearing animals in an environment of continuous omnidirectional noise from birth until mapping (47–53 DAB). Following auditory deprivation, receptive fields remained relatively discrete, but no correlation between rostro-caudal position of the recording site and the angle of the best response was observed. Thus, the Representation of auditory azimuth in the ICX appears to be unperturbed by developmental visual deprivation but is susceptible to developmental auditory deprivation.
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a Topographic Representation of auditory space in the external nucleus of the inferior colliculus of the guinea pig
Brain Research, 1992Co-Authors: K E Binns, Deborah J. Withington, Simon Grant, M J KeatingAbstract:Abstract The possibility that the external nucleus of the inferior colliculus (ICX) of the pigmented guinea-pig contains a map of auditory space has been investigated. Auditory stimuli consisted of broad-band sound delivered under free-field anechoic conditions from a range of positions around the animal's azimuthal axis. The responses of clusters of neurons in the ICX to threshold and to near-threshold stimuli displayed sharp spatial tuning. The responses recorded from rostral ICX revealed a preference for auditory stimuli in the anterior field while more caudal neurons preferentially responded to sounds presented in the posterior field. Neurons at intermediate points, along the rostro-caudal axis of the nucleus, displayed preferences for sound stimuli in appropriately intermediate field positions along the contralateral azimuthal axis. At higher stimulus intensities the spatial tuning of the responses decreased, but the optimal direction of preference was usually retained. The contribution of binaural processing to auditory spatial tuning was evident, since unilateral cochlea ablation destroyed the spatial tuning at higher stimulus intensities. The results presented provide the first evidence that a Topographically ordered Representation of the contralateral auditory azimuth is present in the ICX of a mammal.
