Cargando…

Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals

Two visual signals appearing simultaneously are detected more rapidly than either signal appearing alone. Part of this redundant target effect (RTE) can be attributed to neural summation that has been proposed to occur in the superior colliculus (SC). We report direct evidence in two neurological pa...

Descripción completa

Detalles Bibliográficos
Autores principales: van Koningsbruggen, Martijn, Koller, Kristin, Rafal, Robert D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5323397/
https://www.ncbi.nlm.nih.gov/pubmed/28286472
http://dx.doi.org/10.3389/fnsys.2017.00009
_version_ 1782510014030675968
author van Koningsbruggen, Martijn
Koller, Kristin
Rafal, Robert D.
author_facet van Koningsbruggen, Martijn
Koller, Kristin
Rafal, Robert D.
author_sort van Koningsbruggen, Martijn
collection PubMed
description Two visual signals appearing simultaneously are detected more rapidly than either signal appearing alone. Part of this redundant target effect (RTE) can be attributed to neural summation that has been proposed to occur in the superior colliculus (SC). We report direct evidence in two neurological patients for neural summation in the SC, and that it is mediated by afferent visual information transmitted through its brachium. The RTE was abolished in one patient with a hemorrhage involving the right posterior thalamus that damaged part of the SC and that disrupted its brachium; and in another patient in whom the SC appeared intact but deafferented due to traumatic avulsion of its brachium. In addition reaction time for unilateral targets in the contralesional field was slowed in both patients, providing the first evidence that visual afferents to the SC contribute to the efficiency of target detection.
format Online
Article
Text
id pubmed-5323397
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-53233972017-03-10 Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals van Koningsbruggen, Martijn Koller, Kristin Rafal, Robert D. Front Syst Neurosci Neuroscience Two visual signals appearing simultaneously are detected more rapidly than either signal appearing alone. Part of this redundant target effect (RTE) can be attributed to neural summation that has been proposed to occur in the superior colliculus (SC). We report direct evidence in two neurological patients for neural summation in the SC, and that it is mediated by afferent visual information transmitted through its brachium. The RTE was abolished in one patient with a hemorrhage involving the right posterior thalamus that damaged part of the SC and that disrupted its brachium; and in another patient in whom the SC appeared intact but deafferented due to traumatic avulsion of its brachium. In addition reaction time for unilateral targets in the contralesional field was slowed in both patients, providing the first evidence that visual afferents to the SC contribute to the efficiency of target detection. Frontiers Media S.A. 2017-02-24 /pmc/articles/PMC5323397/ /pubmed/28286472 http://dx.doi.org/10.3389/fnsys.2017.00009 Text en Copyright © 2017 van Koningsbruggen, Koller and Rafal. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Neuroscience
van Koningsbruggen, Martijn
Koller, Kristin
Rafal, Robert D.
Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals
title Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals
title_full Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals
title_fullStr Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals
title_full_unstemmed Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals
title_short Deafferentation of the Superior Colliculus Abolishes Spatial Summation of Redundant Visual Signals
title_sort deafferentation of the superior colliculus abolishes spatial summation of redundant visual signals
topic Neuroscience
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5323397/
https://www.ncbi.nlm.nih.gov/pubmed/28286472
http://dx.doi.org/10.3389/fnsys.2017.00009
work_keys_str_mv AT vankoningsbruggenmartijn deafferentationofthesuperiorcolliculusabolishesspatialsummationofredundantvisualsignals
AT kollerkristin deafferentationofthesuperiorcolliculusabolishesspatialsummationofredundantvisualsignals
AT rafalrobertd deafferentationofthesuperiorcolliculusabolishesspatialsummationofredundantvisualsignals