This study used a go/nogo conditional discrimination learning task to examine the effects of 80-min retention periods filled with sleep (vs wakefulness). Re-learning performance at the delayed retest indicated that sleep benefitted the discrimination behavior in particular by enhancing correct nogo responses. Thus animals who were allowed to sleep improved in withholding and, therefore, actively controlling their response, a task typically associated with prefrontal cortex function. Interestingly, the effect of sleep was independent of whether the animals were retested in the same or in a different context as during learning. Such generalization across contexts reflects a de-contextualization of memory. De-contextualization might be favored by slow wave sleep (SWS) rather than rapid eye movement (REM) sleep, as sleep-induced enhancement of nogo responses did not occur after selective deprivation of REM sleep