Preattentive orienting in adolescents with mental retardation

Visual attention is preattentively drawn to abrupt onsets of stimuli appearing in a visual array. In this experiment, I examined the speed of attentional capture for persons with and without mental retardation. Participants identified target stimuli that were signaled by a valid location cue (20% of the time), an invalid location cue (60% of the time), or no cue (20% of the time). Participants without mental retardation exhibited maximum influence of the cue at cue/target separations that were 100 msec shorter than did participants with mental retardation. These results indicate that processing-speed differences between persons with and those without mental retardation can be observed even when processing resources not involved in the information processing.