Sleep And Declarative Memory Consolidation

Sleep plays an important rob in memory consolidation. Previous studies suggested that memory consolidation can strengthen the stabilization of non-declarative memory more effectively and subject less interference during sleep compared with awaken state. In contrast to non-declarative memory, the rote of consolidation on declarative memory still remains controversial The present study adopted a facial recognition task to investigate the effect of sleep on declarative memory consolidation, by51healthy subjects were divided into sleep group and wake group. Specifically, they were asked to learn a group of novel human faces with neutral expression and to recognize the following three types of faces, namely identical faces(i.e. direct recognition), the rotated identical faces(i.e. indirect recognition) along with the novel faces. Their behavioral performances (i.e. reaction time, accuracy) as well as electrophysiolgical signal were recorded during this process. As for the reaction time(RT), there is a significant interaction effect was detected between recognition task and group. Post-hoc further analysis showed that the sleep group has longer RT than that of the wake group only in indirect cognition task However, no main or interaction effect in recognition accuracy was found, Moreover, the proportion of REM in total sleep time negatively correlated with the standard RT of direct recognition. In conclusion, these findings indicate that only the sleep processing but not the performance accuracy in the recognition task(esp. during the REM sleep period) can be modulated by memory consolidation, which may help to understand the mechanism underlying elaboration of memory representation during sleep.