Document Detail

Neural control of visual search by frontal eye field: effects of unexpected target displacement on visual selection and saccade preparation.
MedLine Citation:
PMID:  19261711     Owner:  NLM     Status:  MEDLINE    
The dynamics of visual selection and saccade preparation by the frontal eye field was investigated in macaque monkeys performing a search-step task combining the classic double-step saccade task with visual search. Reward was earned for producing a saccade to a color singleton. On random trials the target and one distractor swapped locations before the saccade and monkeys were rewarded for shifting gaze to the new singleton location. A race model accounts for the probabilities and latencies of saccades to the initial and final singleton locations and provides a measure of the duration of a covert compensation process-target-step reaction time. When the target stepped out of a movement field, noncompensated saccades to the original location were produced when movement-related activity grew rapidly to a threshold. Compensated saccades to the final location were produced when the growth of the original movement-related activity was interrupted within target-step reaction time and was replaced by activation of other neurons producing the compensated saccade. When the target stepped into a receptive field, visual neurons selected the new target location regardless of the monkeys' response. When the target stepped out of a receptive field most visual neurons maintained the representation of the original target location, but a minority of visual neurons showed reduced activity. Chronometric analyses of the neural responses to the target step revealed that the modulation of visually responsive neurons and movement-related neurons occurred early enough to shift attention and saccade preparation from the old to the new target location. These findings indicate that visual activity in the frontal eye field signals the location of targets for orienting, whereas movement-related activity instantiates saccade preparation.
Aditya Murthy; Supriya Ray; Stephanie M Shorter; Jeffrey D Schall; Kirk G Thompson
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't     Date:  2009-03-04
Journal Detail:
Title:  Journal of neurophysiology     Volume:  101     ISSN:  0022-3077     ISO Abbreviation:  J. Neurophysiol.     Publication Date:  2009 May 
Date Detail:
Created Date:  2009-04-21     Completed Date:  2009-06-04     Revised Date:  2014-09-15    
Medline Journal Info:
Nlm Unique ID:  0375404     Medline TA:  J Neurophysiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2485-506     Citation Subset:  IM    
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MeSH Terms
Action Potentials / physiology
Attention / physiology*
Choice Behavior / physiology
Discrimination (Psychology) / physiology*
Fixation, Ocular / physiology
Macaca mulatta
Neurons / physiology*
Photic Stimulation / methods
Reinforcement (Psychology)
Saccades / physiology*
Time Factors
Visual Cortex / cytology*
Visual Fields / physiology*
Visual Pathways / physiology
Grant Support
F32 EY-14502/EY/NEI NIH HHS; P30 EY-08126/EY/NEI NIH HHS; P30 EY008126/EY/NEI NIH HHS; P30 EY008126-20/EY/NEI NIH HHS; P30 HD-015052/HD/NICHD NIH HHS; R01 EY-8890/EY/NEI NIH HHS; R01 EY008890/EY/NEI NIH HHS; R01 EY008890-18/EY/NEI NIH HHS; T32 EY-08126/EY/NEI NIH HHS; Z99 RG999999/RG/CSR NIH HHS; ZIA EY000389-08/EY/NEI NIH HHS

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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