Sleep to find your way: the role of sleep in the consolidation of memory for navigation in humans.

Although a large body of evidence indicates that sleep plays an important role in learning and memory processes, the actual existence of a sleep-dependent spatial memory consolidation has been not firmly established. Here, by using a computerized 3D virtual navigation tool, we were able to show that topographical orientation in humans largely benefits from sleep after learning, while 10 h of wakefulness during the daytime do not exert similar beneficial effects. In particular, navigation performance enhancement needs sleep in the first post-training night, and no further improvements were seen after a second night of sleep.

Sex-related hemispheric lateralization of electrical potentials evoked by arousing negative stimuli.

Recent studies suggest that both sex and cerebral hemisphere influence brain mechanisms associated with emotional memory. Here we used evoked potentials to examine the influence of sex and hemisphere on brain responses to emotional stimuli. Given that the P300 component of the event-related brain potential (ERP) is considered a cognitive neuroelectric phenomenon, we compared left and right hemisphere P300 responses to brief (2 s) presentations of emotionally arousing pictures in men and women.

Sex-related lateralized effect of emotional content on declarative memory: an event related potential study.

Several studies suggest that emotional arousal can promote memory storage. In this study, we evaluated the effects of emotional content on declarative memory, utilizing an adaptation of two versions of the same story, with different arousing properties (neutral or emotional), which have been already employed in experiments involving the enhancing effects of emotions on memory retention. We used event related potentials (ERP) to evaluate whether there is a sex-related hemispheric lateralization of electrical potentials elicited by the emotional content of a story.

The induction of cyclic nucleotide phosphodiesterase 4 gene (PDE4D) impairs memory in a water maze task.

In this study, the effects on memory of intraperitoneal post-training administration of cyclic nucleotide phosphodiesterase (PDE) inhibitors, DC-TA 46 and rolipram, were tested using a visible/hidden-platform water maze task. The effects of these compounds on cyclic nucleotide levels in the hippocampal formation (HF) and striatum (CP) were also assessed, by enzymatic immunoassay (EIA). The results obtained from rats trained in the visible-platform task were not significantly different from controls.