The Experts below are selected from a list of 16830 Experts worldwide ranked by ideXlab platform

Victoria Jones - One of the best experts on this subject based on the ideXlab platform.

  • memories are made of this the effects of time on stored visual knowledge in a case of visual agnosia
    Brain, 1999
    Co-Authors: Jane M Riddoch, Theresa A Gannon, William Blott, Glyn W. Humphreys, Victoria Jones
    Abstract:

    : We report the effects of the passage of time on the longterm visual knowledge for objects in a patient with visual agnosia (H.J.A.). The naming of real objects was found to have improved, although this was not associated with any change in H.J.A.'s basic Perceptual abilities which were stable over a 16-year period. The improvement in object naming was attributed to better use of non-contour-based visual information (such as surface detail and depth cues). In addition, we demonstrate a deterioration in H.J.A.'s long-term memory for the visual properties of objects, and argue that this has occurred as a result of his having impaired Perceptual Input. The deterioration was only apparent in drawing from memory and in the verbal descriptions of items; with forced-choice testing, H.J.A. operated at ceiling; we propose that current tests of visual imagery may not be sufficiently sensitive to detect subtle impairments of visual memory. Our findings can be taken to indicate that Perceptual and memorial processes are not functionally independent, but are linked in an interactive manner.

  • memories are made of this the effects of time on stored visual knowledge in a case of visual agnosia
    Brain, 1999
    Co-Authors: Jane M Riddoch, Theresa A Gannon, William Blott, Glyn W. Humphreys, Victoria Jones
    Abstract:

    We report the effects of the passage of time on the longterm visual knowledge for objects in a patient with visual agnosia (H.J.A.). The naming of real objects was found to have improved, although this was not associated with any change in H,J,A,'s basic Perceptual abilities which were stable ever a 16-year period, The improvement in object naming was attributed to better use of non-contour-based visual information (such as surface detail and depth cues). In addition, we demonstrate a deterioration in H.J.A.'s long-term memory for the visual properties of objects, and argue that this has occurred as a result of his having impaired Perceptual Input, The deterioration was only apparent in drawing from memory and in the verbal descriptions of items; with forced-choice testing, H.J.A. operated at ceiling; we propose that current tests of visual imagery may not be sufficiently sensitive to detect subtle impairments of visual memory, Our findings can be taken to indicate that Perceptual and memorial processes are not functionally independent, but are linked in an interactive manner.

Bijan Pesaran - One of the best experts on this subject based on the ideXlab platform.

  • sensory motor transformations for speech occur bilaterally
    Nature, 2014
    Co-Authors: Gregory B. Cogan, Thomas Thesen, Chad Carlson, Werner Doyle, Orrin Devinsky, Bijan Pesaran
    Abstract:

    Direct neural recordings from electrodes over bilateral cortices show that sensory–motor transformations for speech occur bilaterally; neural responses are robust during both perception and production in an overt word-repetition task, and bilateral sensory–motor responses can perform transformations between speech-perception and speech-production representations during a non-word transformation task. It has long been believed that speech perception and production are linked, but the neural mechanisms underlying this connection and the question of hemispheric lateralization for either function have remained unknown. Here, Bijan Pesaran and colleagues reveal that sensory–motor transformations occur bilaterally and thus underscore the existence of a bilateral sensory–motor system for speech. This contrasts with higher-order language processes, which are lateralized to the left hemisphere. Historically, the study of speech processing has emphasized a strong link between auditory Perceptual Input and motor production output1,2,3,4. A kind of ‘parity’ is essential, as both perception- and production-based representations must form a unified interface to facilitate access to higher-order language processes such as syntax and semantics, believed to be computed in the dominant, typically left hemisphere5,6. Although various theories have been proposed to unite perception and production2,7, the underlying neural mechanisms are unclear. Early models of speech and language processing proposed that Perceptual processing occurred in the left posterior superior temporal gyrus (Wernicke’s area) and motor production processes occurred in the left inferior frontal gyrus (Broca’s area)8,9. Sensory activity was proposed to link to production activity through connecting fibre tracts, forming the left lateralized speech sensory–motor system10. Although recent evidence indicates that speech perception occurs bilaterally11,12,13, prevailing models maintain that the speech sensory–motor system is left lateralized11,14,15,16,17,18 and facilitates the transformation from sensory-based auditory representations to motor-based production representations11,15,16. However, evidence for the lateralized computation of sensory–motor speech transformations is indirect and primarily comes from stroke patients that have speech repetition deficits (conduction aphasia) and studies using covert speech and haemodynamic functional imaging16,19. Whether the speech sensory–motor system is lateralized, like higher-order language processes, or bilateral, like speech perception, is controversial. Here we use direct neural recordings in subjects performing sensory–motor tasks involving overt speech production to show that sensory–motor transformations occur bilaterally. We demonstrate that electrodes over bilateral inferior frontal, inferior parietal, superior temporal, premotor and somatosensory cortices exhibit robust sensory–motor neural responses during both perception and production in an overt word-repetition task. Using a non-word transformation task, we show that bilateral sensory–motor responses can perform transformations between speech-perception- and speech-production-based representations. These results establish a bilateral sublexical speech sensory–motor system.

Chad Carlson - One of the best experts on this subject based on the ideXlab platform.

  • sensory motor transformations for speech occur bilaterally
    Nature, 2014
    Co-Authors: Gregory B. Cogan, Thomas Thesen, Chad Carlson, Werner Doyle, Orrin Devinsky, Bijan Pesaran
    Abstract:

    Direct neural recordings from electrodes over bilateral cortices show that sensory–motor transformations for speech occur bilaterally; neural responses are robust during both perception and production in an overt word-repetition task, and bilateral sensory–motor responses can perform transformations between speech-perception and speech-production representations during a non-word transformation task. It has long been believed that speech perception and production are linked, but the neural mechanisms underlying this connection and the question of hemispheric lateralization for either function have remained unknown. Here, Bijan Pesaran and colleagues reveal that sensory–motor transformations occur bilaterally and thus underscore the existence of a bilateral sensory–motor system for speech. This contrasts with higher-order language processes, which are lateralized to the left hemisphere. Historically, the study of speech processing has emphasized a strong link between auditory Perceptual Input and motor production output1,2,3,4. A kind of ‘parity’ is essential, as both perception- and production-based representations must form a unified interface to facilitate access to higher-order language processes such as syntax and semantics, believed to be computed in the dominant, typically left hemisphere5,6. Although various theories have been proposed to unite perception and production2,7, the underlying neural mechanisms are unclear. Early models of speech and language processing proposed that Perceptual processing occurred in the left posterior superior temporal gyrus (Wernicke’s area) and motor production processes occurred in the left inferior frontal gyrus (Broca’s area)8,9. Sensory activity was proposed to link to production activity through connecting fibre tracts, forming the left lateralized speech sensory–motor system10. Although recent evidence indicates that speech perception occurs bilaterally11,12,13, prevailing models maintain that the speech sensory–motor system is left lateralized11,14,15,16,17,18 and facilitates the transformation from sensory-based auditory representations to motor-based production representations11,15,16. However, evidence for the lateralized computation of sensory–motor speech transformations is indirect and primarily comes from stroke patients that have speech repetition deficits (conduction aphasia) and studies using covert speech and haemodynamic functional imaging16,19. Whether the speech sensory–motor system is lateralized, like higher-order language processes, or bilateral, like speech perception, is controversial. Here we use direct neural recordings in subjects performing sensory–motor tasks involving overt speech production to show that sensory–motor transformations occur bilaterally. We demonstrate that electrodes over bilateral inferior frontal, inferior parietal, superior temporal, premotor and somatosensory cortices exhibit robust sensory–motor neural responses during both perception and production in an overt word-repetition task. Using a non-word transformation task, we show that bilateral sensory–motor responses can perform transformations between speech-perception- and speech-production-based representations. These results establish a bilateral sublexical speech sensory–motor system.

Jane M Riddoch - One of the best experts on this subject based on the ideXlab platform.

  • memories are made of this the effects of time on stored visual knowledge in a case of visual agnosia
    Brain, 1999
    Co-Authors: Jane M Riddoch, Theresa A Gannon, William Blott, Glyn W. Humphreys, Victoria Jones
    Abstract:

    : We report the effects of the passage of time on the longterm visual knowledge for objects in a patient with visual agnosia (H.J.A.). The naming of real objects was found to have improved, although this was not associated with any change in H.J.A.'s basic Perceptual abilities which were stable over a 16-year period. The improvement in object naming was attributed to better use of non-contour-based visual information (such as surface detail and depth cues). In addition, we demonstrate a deterioration in H.J.A.'s long-term memory for the visual properties of objects, and argue that this has occurred as a result of his having impaired Perceptual Input. The deterioration was only apparent in drawing from memory and in the verbal descriptions of items; with forced-choice testing, H.J.A. operated at ceiling; we propose that current tests of visual imagery may not be sufficiently sensitive to detect subtle impairments of visual memory. Our findings can be taken to indicate that Perceptual and memorial processes are not functionally independent, but are linked in an interactive manner.

  • memories are made of this the effects of time on stored visual knowledge in a case of visual agnosia
    Brain, 1999
    Co-Authors: Jane M Riddoch, Theresa A Gannon, William Blott, Glyn W. Humphreys, Victoria Jones
    Abstract:

    We report the effects of the passage of time on the longterm visual knowledge for objects in a patient with visual agnosia (H.J.A.). The naming of real objects was found to have improved, although this was not associated with any change in H,J,A,'s basic Perceptual abilities which were stable ever a 16-year period, The improvement in object naming was attributed to better use of non-contour-based visual information (such as surface detail and depth cues). In addition, we demonstrate a deterioration in H.J.A.'s long-term memory for the visual properties of objects, and argue that this has occurred as a result of his having impaired Perceptual Input, The deterioration was only apparent in drawing from memory and in the verbal descriptions of items; with forced-choice testing, H.J.A. operated at ceiling; we propose that current tests of visual imagery may not be sufficiently sensitive to detect subtle impairments of visual memory, Our findings can be taken to indicate that Perceptual and memorial processes are not functionally independent, but are linked in an interactive manner.

Gregory B. Cogan - One of the best experts on this subject based on the ideXlab platform.

  • sensory motor transformations for speech occur bilaterally
    Nature, 2014
    Co-Authors: Gregory B. Cogan, Thomas Thesen, Chad Carlson, Werner Doyle, Orrin Devinsky, Bijan Pesaran
    Abstract:

    Direct neural recordings from electrodes over bilateral cortices show that sensory–motor transformations for speech occur bilaterally; neural responses are robust during both perception and production in an overt word-repetition task, and bilateral sensory–motor responses can perform transformations between speech-perception and speech-production representations during a non-word transformation task. It has long been believed that speech perception and production are linked, but the neural mechanisms underlying this connection and the question of hemispheric lateralization for either function have remained unknown. Here, Bijan Pesaran and colleagues reveal that sensory–motor transformations occur bilaterally and thus underscore the existence of a bilateral sensory–motor system for speech. This contrasts with higher-order language processes, which are lateralized to the left hemisphere. Historically, the study of speech processing has emphasized a strong link between auditory Perceptual Input and motor production output1,2,3,4. A kind of ‘parity’ is essential, as both perception- and production-based representations must form a unified interface to facilitate access to higher-order language processes such as syntax and semantics, believed to be computed in the dominant, typically left hemisphere5,6. Although various theories have been proposed to unite perception and production2,7, the underlying neural mechanisms are unclear. Early models of speech and language processing proposed that Perceptual processing occurred in the left posterior superior temporal gyrus (Wernicke’s area) and motor production processes occurred in the left inferior frontal gyrus (Broca’s area)8,9. Sensory activity was proposed to link to production activity through connecting fibre tracts, forming the left lateralized speech sensory–motor system10. Although recent evidence indicates that speech perception occurs bilaterally11,12,13, prevailing models maintain that the speech sensory–motor system is left lateralized11,14,15,16,17,18 and facilitates the transformation from sensory-based auditory representations to motor-based production representations11,15,16. However, evidence for the lateralized computation of sensory–motor speech transformations is indirect and primarily comes from stroke patients that have speech repetition deficits (conduction aphasia) and studies using covert speech and haemodynamic functional imaging16,19. Whether the speech sensory–motor system is lateralized, like higher-order language processes, or bilateral, like speech perception, is controversial. Here we use direct neural recordings in subjects performing sensory–motor tasks involving overt speech production to show that sensory–motor transformations occur bilaterally. We demonstrate that electrodes over bilateral inferior frontal, inferior parietal, superior temporal, premotor and somatosensory cortices exhibit robust sensory–motor neural responses during both perception and production in an overt word-repetition task. Using a non-word transformation task, we show that bilateral sensory–motor responses can perform transformations between speech-perception- and speech-production-based representations. These results establish a bilateral sublexical speech sensory–motor system.