Influence of contextual cues on the choice reaction time of mildly retarded adults.

Nonretarded and mildly retarded subjects were compared on an 8-choice reaction-time (RT) task. Removing a midline that divided the stimulus display in halves slowed RTs of retarded subjects to stimuli adjacent to the line. In the absence of this line, retarded subjects were also much more dependent upon the position of the preceding stimulus and response.