Incorporation of fragmented visuo-olfactory episodic memory into dreams and its association with memory performance
Scientific Reports October 30, 2019 Jane Plailly, Manon Villalba, Raphael Vallat et al. 42 citations
Whether dream content reflects memory consolidation is an open question. After reviewing the literature, an experiment tested if incorporating recently learned material into dreams relates to better memory after sleep. Thirty-two high dream recallers freely explored new visuo-olfactory episodes for 3 consecutive days. During subsequent nights, they woke at 5am and their usual waking time to record dreams; 120 dreams were reported. Elements from the encoding phase appeared in 37 dreams, mostly visual rather than olfactory. On day 4, participants with learning-related dreams showed similar odor recognition and odor-evoked episodic memory as others, but significantly better visuo-spatial memory of the episodes. Results suggest the learning phase is loosely incorporated into dreams and this incorporation is associated with sleep-related memory consolidation.