The Effect of Sleep on the Consolidation of Positive Emotional Memories

Sleep enhances the emotional memory trade-off effect, whereby emotional components of a scene are enhanced in memory while the corresponding neutral components are reduced. However, while previous investigations have only investigated negative scenes, the current study examined this effect for positive scenes. Participants viewed scenes composed of positive or neutral objects placed on neutral backgrounds in preparation for a surprise Remember/Know memory test 12 hours later. Those in the wake group remained awake during this delay while those in the sleep group remained in the lab overnight while their sleep was recorded. Results revealed that the sleep group had better memory than the wake group, especially for positive components of scenes. Further, there was a negative correlation between REM latency and familiarity for the positive objects, indicating a role for sleep in processing positive information.