Sex differences in attentional processes in adult rats as measured by performance on the 5-choice serial reaction time task

The goal of the current study was to explore sex differences in attentional processes in adult rats using a test of attention shown to be dependent upon the prefrontal cortex. Male and female adult Long-Evans rats were trained on the 5-choice serial reaction time task. This task requires rats to identify the location of a brief light stimulus among five possible locations. Performance was assessed under baseline conditions and under behavioral challenge conditions during which task difficulty was increased. Behavioral challenge conditions included shortening the stimulus duration, shortening the time before the onset of the stimulus, lengthening the time before the onset of the stimulus, and presenting a distracting noise. Analyses across baseline and all challenge conditions revealed that vigilance or sustained attention was more disrupted in female rats than it was in male rats, as measured by percent correct and number of omissions. Analyses also revealed that inhibitory control was more disrupted in male rats than it was in female rats, as measured by number of premature responses. These differences were most prominent when the onset of the stimulus was unpredictably lengthened. There were no differences in reward collection latency or correct response latency indicating no differences in motivation or sensory processes between the sexes. These results indicate that under challenging conditions adult female rats are more prone to make errors of vigilance than are adult male rats, and adult male rats are more prone to make errors of inhibitory control than are adult female rats. (c) 2012 Elsevier B.V. All rights reserved.