Linked Life Data

9463444

Source:http://linkedlifedata.com/resource/pubmed/id/9463444

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-4-14
pubmed:abstractText
A new approach was developed to investigate the role of visual-, movement-, and fixation-related neural activity in gaze control. We recorded unit activity in the frontal eye fields (FEF), an area in frontal cortex that plays a central role in the production of purposeful eye movements, of monkeys (Macaca mulatta) performing visually and memory-guided saccades. The countermanding paradigm was employed to assess whether single cells generate signals sufficient to control movement production. The countermanding paradigm consists of a task that manipulates the monkeys' ability to withhold planned saccades combined with an analysis based on a race model that provides an estimate of the time needed to cancel the movement that is being prepared. We obtained clear evidence that FEF neurons with eye movement-related activity generate signals sufficient to control the production of gaze shifts. Movement-related activity, which was growing toward a trigger threshold as the saccades were prepared, decayed in response to the stop signal within the time required to cancel the saccade. Neurons with fixation-related activity were less common, but during the countermanding paradigm, these neurons exhibited an equally clear gaze-control signal. Fixation cells that had a pause in firing before a saccade exhibited elevated activity in response to the stop signal within the time that the saccade was cancelled. In contrast to cells with movement or fixation activity, neurons with only visually evoked activity exhibited no evidence of signals sufficient to control the production of gaze shifts. However, a fraction of tonic visual cells exhibited a reduction of activity once a saccade command had been cancelled even though the visual target was still present in the receptive field. These findings demonstrate the use of the countermanding paradigm in identifying neural signatures of motor control and provide new information about the fine balance between gaze shifting and gaze holding mechanisms.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
817-34
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Role of frontal eye fields in countermanding saccades: visual, movement, and fixation activity.
pubmed:affiliation
Vanderbilt Vision Research Center, Department of Psychology, Vanderbilt University, Nashville, Tennessee 37240, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't