Abstract
BACKGROUND: Visual neglect is an attentional deficit typically resulting from parietal cortex lesion and sometimes frontal lesion. Patients fail to attend to objects and events in the visual hemifield contralateral to their lesion during visual search. METHODOLOGY/PRINCIPAL FINDING: The aim of this work was to examine the effects of parietal and frontal lesion in an existing computational model of visual attention and search and simulate visual search behaviour under lesion conditions. We find that unilateral parietal lesion in this model leads to symptoms of visual neglect in simulated search scan paths, including an inhibition of return (IOR) deficit, while frontal lesion leads to milder neglect and to more severe deficits in IOR and perseveration in the scan path. During simulations of search under unilateral parietal lesion, the model's extrastriate ventral stream area exhibits lower activity for stimuli in the neglected hemifield compared to that for stimuli in the normally perceived hemifield. This could represent a computational correlate of differences observed in neuroimaging for unconscious versus conscious perception following parietal lesion. CONCLUSIONS/SIGNIFICANCE: Our results lead to the prediction, supported by effective connectivity evidence, that connections between the dorsal and ventral visual streams may be an important factor in the explanation of perceptual deficits in parietal lesion patients and of conscious perception in general.
DOI
10.1371/journal.pone.0011128
Publication Date
2010-06-15
Publication Title
PLoS ONE
Volume
5
Issue
6
Publisher
Public Library of Science (PLoS)
ISSN
1932-6203
Embargo Period
2024-11-22
First Page
e11128
Last Page
e11128
Recommended Citation
Lanyon, L., & Denham, S. (2010) 'Modelling Visual Neglect: Computational Insights into Conscious Perception', PLoS ONE, 5(6), pp. e11128-e11128. Public Library of Science (PLoS): Available at: https://doi.org/10.1371/journal.pone.0011128
