Tested 9 rhesus monkeys with lesions of the dorsolateral frontal cortex 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 Ss with frontal lesions than for normal controls. The increased distractibility is due to an increase in the duration of distraction-evoked behavior and, in the case of the spatial distractors, 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 Ss with frontal lesions, were found to be more sensitive to variations in the spatial location of the distractor than to changes in the visual aspect of the cues. (PsycINFO Database Record (c) 2006 APA, all rights reserved)