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ISSN
0898-929X
E-ISSN
1530-8898
2014 Impact factor:
4.69

Journal of Cognitive Neuroscience

Fall 1994, Vol. 6, No. 4, Pages 377-387
(doi: 10.1162/jocn.1994.6.4.377)
© 1994 by the Massachusetts Institute of Technology
Mechanisms of Spatial Attention: The Relation of Macrostructure to Microstructure in Parietal Neglect
Article PDF (1.02 MB)
Abstract

Parietal-damaged patients respond abnormally slowly to targets presented in the affected hemifield when preceded by cues in the intact hemifield. This inability to disengage attention from the ipsilesional field to reengage it in the contralesional field has been interpreted as evidence for a distinct “disengage” mechanism, localized in parietal cortex. We present a computational model that accounts for normal attentional effects by interactivity and competition among representations of different locations in space, without a dedicated “disengage” mechanism. We show that when the model is lesioned, it produces the “disengage deficit” shown by parietal-damaged patients. This suggests that the deficit observed in such patients can be understood as an emergent property of interactions among the remaining parts of the system, and need not imply the existence of a dedicated “disengage” mechanism in the normal brain.