%0 Journal Article
%T Response selection and initiation in speeded reactions: a pupillometric analysis
%J Journal of experimental psychology: human perception and performance
%D 1983
%A Richer, F.
%A Silverman, C.
%A Beatty, J.
%V 9
%N 3
%P 360-370
%X Three studies are described in which the task-evoked pupillary response is recorded during simple and disjunctive reactions in order to examine its contribution as a measure of the motoric and cognitive aspects of performance in these tasks. In simple reactions a pupillary dilation began about 1.5 sec before the imperative stimulus and peaked about 1 sec after the stimulus. The rate of dilation was inversely related to the interstimulus interval. In disjunctive reactions, both "Go" and "No-Go" responses elicited significant dilations but the No-Go dilation was smaller than the Go dilation. When the response was delayed 2.5 sec after the discrimination stimulus, the dilation to both Go and No-Go responses was much reduced. The pupillary response related to response selection was estimated at 55% of that associated with motor preparation and execution. The probability of responding was found to affect the amplitude of the dilation to No-Go responses but not that to Go responses. The data point to a significant contribution of preparatory motor processing in No-Go reactions and to an overlap between decisional and motoric processing in disjunctive reactions.<p /><p>Language: en</p>
%G en
%I American Psychological Association
%@ 0096-1523
%U http://dx.doi.org/