LAUSR

Early childhood naps have been shown to support emotional memory consolidation, but this benefit only emerges the following day. It is unknown whether consolidation occurs during the nap itself, or if napping only prepares memories for overnight consolidation. In this study, we used a forced-choice recognition task to determine whether naps protect emotional memories against post-nap interference, which would indicate the occurrence of consolidation. Preschool children (33–67 months; N=63) viewed neutral faces paired with negative or neutral descriptions. Following a nap or an equal interval awake (within-subjects, order counterbalanced, ~1 week apart), half of these participants (N=33) were presented with an interfering set of faces and descriptions, while the other half (N=30) did not receive interference. For all participants, recognition of the original faces was probed after encoding, after the nap or wake interval, and the next morning. To assess the influence of napping on changes in emotional memory, 2 (stimulus valence: negative vs. neutral) x 2 (condition: nap vs. wake) repeated-measures ANOVAs were performed. Recall of negative and neutral items did not immediately differ between the nap and wake conditions for the participants who received no interference. 24 hours later, these children trended towards recalling negative and neutral items better if they had napped the previous day (condition main effect: F(1,29)=3.539, p=0.070). In contrast, participants who received interference recalled fewer negative items than neutral items immediately following a nap (p=0.034), while this difference did not emerge following an interval awake. Our results suggest that naps initially destabilize emotional memories rather than protecting them against interference. However, this initial destabilization may reflect the partial processing of memories during naps, perhaps allowing for enhanced long-term consolidation. Overall, our findings provide important insight into the mechanism of nap-dependent emotional processing. Supported by NIH R01 HL111695 and an Honors Research Grant from Commonwealth Honors College