Effects of spatial and nonspatial distractors on performance latency of monkeys with frontal lesions.

Subjects with lesions of the dorsolateral frontal cortex were tested in a situation where a behavioral task was occasionally interrupted by the presentation of visual or auditory distractors, and the increase in response latency due to the distractor was greater for the subjects with frontal lesions than for normal controls.

Abstract

Rhesus monke.vs with lesions of the dorsolateral frontal cortex were tested in a situation where a behavioral task was occasionally interrupted by the presentation of visual or auditory distractors. The increase in response latency due to the distractor was greater for the subjects with frontal lesions than for normal controls. The increased distractibili tv is due to an increase in the dumtion of distraction-evoked behavior 'and, in the case of the spatial distmctors, also to an increase in the probability that the distracting input will be sampled. Behavioral habituation (decrease in distraction duration) took place at the same rate in both groups, although the asymptotic levels eventually reached might differ under appropriate conditions. The subjects with frontal lesions, el'en more than their controls, were found to be more sensitive to variations in t.he spatial location of the distractor than to changes in the visual aspect of the cues.