Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2002-3-21
pubmed:abstractText
The ability to find targets embedded within complex visual environments requires the dynamic programming of visuomotor search behaviors. Functional magnetic resonance imaging was used to image subjects while they visually searched for targets embedded among foils. Visuomotor search activated the posterior parietal cortex and the frontal eye fields. Both regions showed a greater number of activated voxels on the right, consistent with the known pattern of right hemispheric dominance for spatial attention. The superior colliculus showed prominent activation in the search versus eye movement contrast, demonstrating, for the first time in humans, activation of this region specifically related to an exploratory attentional contingency. An analysis of effective connectivity demonstrated that the search-dependent variance in the activity of the superior colliculus was significantly influenced by the activity in a network of cortical regions including the right frontal eye fields and bilateral parietal and occipital cortices. These experiments also revealed the presence of a mosaic of activated sites within the frontal eye field region wherein saccadic eye movements, covert shifts of attention, and visuomotor search elicited overlapping but not identical zones of activation. In contrast to the existing literature on functional imaging, which has focused on covert shifts of spatial attention, this study helps to characterize the functional anatomy of overt spatial exploration.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1053-8119
pubmed:author
pubmed:copyrightInfo
(C)2002 Elsevier Science (USA).
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
970-82
pubmed:dateRevised
2011-9-22
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Functional anatomy of visual search: regional segregations within the frontal eye fields and effective connectivity of the superior colliculus.
pubmed:affiliation
The Northwestern Cognitive Brain Mapping Group, Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Medical School, Chicago, Illinois 60611, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't