Visual search and target-directed action

There have been many investigations of people's ability to search for and d etect the presence of identity-defined targets in cluttered visual scenes. Such identity search tasks do not adequately represent those situations in which directed actions must be made to targets. Vision for identification a nd vision for action are processed in parallel, so action processing of all potential target stimuli proceeds until identification processes distingui sh the target. Resulting visuomotor competition from distracters can have m easurable behavioral effects on the performance of target-directed actions. Such effects are reported here for a task in which human participants reac hed for red targets in the presence of yellow distractors. The experiments were designed to show that increases in reaching response time could be att ributed to visuomotor processing of distracters.