The effect of stimulus availability on task choice in voluntary task switching.
The voluntary task switching paradigm allows subjects to choose which task to perform on each trial in a stimulus environment affording multiple tasks. The present study examined the effect of stimulus availability on task choice. Subjects viewed displays containing a digit and a letter and performed either an even/odd or a consonant/vowel judgment on each trial. The target stimuli appeared with a stimulus onset asynchrony (SOA) of 0, 50, 100, or 150 msec. The probability of performing the task associated with Stimulus 1 increased as SOA increased, indicating an effect of external or stimulus-driven factors on task choice. This effect of stimulus availability on task choice was greater when the response-stimulus interval was 400 msec than when it was 2,000 msec. This interaction of preparation interval and stimulus availability is explained within a model of task choice that includes both internal processes and external influences.
Arrington
Catherine M
CM
Department of Psychology, Lehigh University, Bethlehem, Pennsylvania, USA. kate.arrington@lehigh.edu
D002755:Choice Behavior; D006801:Humans; D011597:Psychomotor Performance; D014836:Volition