Abstract
Sleep supports the consolidation of declarative memory in children and adults. However, it is unclear whether sleep improves odor memory in children as well as adults. Thirty healthy children (mean age of 10.6, ranging from 8–12 yrs.) and 30 healthy adults (mean age of 25.4, ranging from 20–30 yrs.) participated in an incidental odor recognition paradigm. While learning of 10 target odorants took place in the evening and retrieval (10 target and 10 distractor odorants) the next morning in the sleep groups (adults: n = 15, children: n = 15), the time schedule was vice versa in the wake groups (n = 15 each). During encoding, adults rated odors as being more familiar. After the retention interval, adult participants of the sleep group recognized odors better than adults in the wake group. While children in the wake group showed memory performance comparable to the adult wake group, the children sleep group performed worse than adult and children wake groups. Correlations between memory performance and familiarity ratings during encoding indicate that pre-experiences might be critical in determining whether sleep improves or worsens memory consolidation.
Highlights
The olfactory system is characterized by remarkable plasticity, and odors have a strong ability to spontaneously evoke emotional and autobiographical memories [1,2,3]
Subsequent t-tests for independent samples revealed that the adult sleep group performed better than the adult wake group [sleep: 1.6±0.14; wake: 1.1±0.15; sleep vs. wake: t(28) = 2.2, p = .038]
While the adult sleep group showed better odor recognition performance than the adult wake group, the opposite was true in children
Summary
The olfactory system is characterized by remarkable plasticity, and odors have a strong ability to spontaneously evoke emotional and autobiographical memories [1,2,3]. Some associations between odors and autobiographical episodes endure lifelong even without rehearsing [4]. Responses to the majority of odors, are not inherent but experience-dependent, and, during infancy, most odors are unfamiliar and meaningless until they become associated with personal experiences [5]. Encoded information is stored temporarily in the hippocampus; during post-learning slow wave sleep (SWS) hippocampal representations become integrated into pre-existing neocortical memory systems, leading to better memory performance for personal episodes, word-pair or object-location association tasks after sleep [8,9,10].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
