Cueing negative memories during slow-wave sleep reduces affective tone

Tsimpanouli, M. , Elliott, R. , Anderson, I. & Lewis, P.

University of Manchester

Cueing replay of memories during slow-wave sleep (SWS) has been shown to strengthen their consolidation. Rapid eye movement sleep is considered to be the main effector of consolidating emotional memories, while it decreases their affective tone. Here, participants rated 36 negative and 36 neutral pictures, paired with semantically related sounds, for valence and arousal. Then, they learned the location of each picture on the screen while hearing the matching sound. Their memory was tested once before sleeping and once the following morning. After the second memory test, participants rated again the stimuli for valence and arousal. During the night, half of the negative and half of the neutral sounds were played during SWS. Performance on the memory task remained the same for the stimuli that were cued during sleep, whereas it deteriorated for the non-cued stimuli (p<0.05). Furthermore, we observed a cueing*emotion effect on the overnight change of arousal ratings, which decreased more for all neutral and cued negative stimuli but less for the non-cued negative stimuli (p<0.02). Our results provide evidence that cueing memory replay during SWS benefits consolidation, regardless of valence, and enhances the extent to which the affective tone of negative stimuli decreases overnight.