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Schizophrenia and visual backward masking: a general deficit of target enhancement

The obvious symptoms of schizophrenia are of cognitive and psychopathological nature. However, schizophrenia affects also visual processing which becomes particularly evident when stimuli are presented for short durations and are followed by a masking stimulus. Visual deficits are of great interest...

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Autores principales: Herzog, Michael H., Roinishvili, Maya, Chkonia, Eka, Brand, Andreas
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3653113/
https://www.ncbi.nlm.nih.gov/pubmed/23717290
http://dx.doi.org/10.3389/fpsyg.2013.00254
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author Herzog, Michael H.
Roinishvili, Maya
Chkonia, Eka
Brand, Andreas
author_facet Herzog, Michael H.
Roinishvili, Maya
Chkonia, Eka
Brand, Andreas
author_sort Herzog, Michael H.
collection PubMed
description The obvious symptoms of schizophrenia are of cognitive and psychopathological nature. However, schizophrenia affects also visual processing which becomes particularly evident when stimuli are presented for short durations and are followed by a masking stimulus. Visual deficits are of great interest because they might be related to the genetic variations underlying the disease (endophenotype concept). Visual masking deficits are usually attributed to specific dysfunctions of the visual system such as a hypo- or hyper-active magnocellular system. Here, we propose that visual deficits are a manifestation of a general deficit related to the enhancement of weak neural signals as occurring in all other sorts of information processing. We summarize previous findings with the shine-through masking paradigm where a shortly presented vernier target is followed by a masking grating. The mask deteriorates visual processing of schizophrenic patients by almost an order of magnitude compared to healthy controls. We propose that these deficits are caused by dysfunctions of attention and the cholinergic system leading to weak neural activity corresponding to the vernier. High density electrophysiological recordings (EEG) show that indeed neural activity is strongly reduced in schizophrenic patients which we attribute to the lack of vernier enhancement. When only the masking grating is presented, EEG responses are roughly comparable between patients and control. Our hypothesis is supported by findings relating visual masking to genetic deviants of the nicotinic α7 receptor (CHRNA7).
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spelling pubmed-36531132013-05-28 Schizophrenia and visual backward masking: a general deficit of target enhancement Herzog, Michael H. Roinishvili, Maya Chkonia, Eka Brand, Andreas Front Psychol Psychology The obvious symptoms of schizophrenia are of cognitive and psychopathological nature. However, schizophrenia affects also visual processing which becomes particularly evident when stimuli are presented for short durations and are followed by a masking stimulus. Visual deficits are of great interest because they might be related to the genetic variations underlying the disease (endophenotype concept). Visual masking deficits are usually attributed to specific dysfunctions of the visual system such as a hypo- or hyper-active magnocellular system. Here, we propose that visual deficits are a manifestation of a general deficit related to the enhancement of weak neural signals as occurring in all other sorts of information processing. We summarize previous findings with the shine-through masking paradigm where a shortly presented vernier target is followed by a masking grating. The mask deteriorates visual processing of schizophrenic patients by almost an order of magnitude compared to healthy controls. We propose that these deficits are caused by dysfunctions of attention and the cholinergic system leading to weak neural activity corresponding to the vernier. High density electrophysiological recordings (EEG) show that indeed neural activity is strongly reduced in schizophrenic patients which we attribute to the lack of vernier enhancement. When only the masking grating is presented, EEG responses are roughly comparable between patients and control. Our hypothesis is supported by findings relating visual masking to genetic deviants of the nicotinic α7 receptor (CHRNA7). Frontiers Media S.A. 2013-05-14 /pmc/articles/PMC3653113/ /pubmed/23717290 http://dx.doi.org/10.3389/fpsyg.2013.00254 Text en Copyright © 2013 Herzog, Roinishvili, Chkonia and Brand. http://creativecommons.org/licenses/by/3.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
spellingShingle Psychology
Herzog, Michael H.
Roinishvili, Maya
Chkonia, Eka
Brand, Andreas
Schizophrenia and visual backward masking: a general deficit of target enhancement
title Schizophrenia and visual backward masking: a general deficit of target enhancement
title_full Schizophrenia and visual backward masking: a general deficit of target enhancement
title_fullStr Schizophrenia and visual backward masking: a general deficit of target enhancement
title_full_unstemmed Schizophrenia and visual backward masking: a general deficit of target enhancement
title_short Schizophrenia and visual backward masking: a general deficit of target enhancement
title_sort schizophrenia and visual backward masking: a general deficit of target enhancement
topic Psychology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3653113/
https://www.ncbi.nlm.nih.gov/pubmed/23717290
http://dx.doi.org/10.3389/fpsyg.2013.00254
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