Objectives: Individuals with depression demonstrate distinctive sleep disturbances and memory biases. While both sleep and emotionality have been found to modulate memory consolidation in healthy adults, surprisingly few studies have examined the relationship among sleep, emotionality and memory consolidation in depression. The current study investigated 1) the effect of a 90-minute daytime napping on emotional memory consolidation in clinical depression and healthy adults, and 2) the role of sleep physiology in emotional memory consolidation. Methods: Sleep-dependent memory consolidation was assessed for 96 adults (either healthy or diagnosed with Major Depression) using a napping paradigm and an incidental memory task. Results: A short daytime nap was found to enhance the memory consolidation of emotional stimuli in healthy controls, in which a preferential consolidation of negative stimuli was observed. In contrast, sleep failed to facilitate memory consolidation in depressed participants, specifically in the decrement of negative memory. In addition, individuals with depression in the nap condition were found to have unexpectedly higher amount of SlowWave Sleep (SWS) and shorter Rapid-Eye-Movement (REM) sleep during the nap than their never-depressed counterparts. The altered sleep architeure was possibly associated with suboptimal memory consolidation during sleep in depressed participants. Conclusion: This study was the first in examining the interplay between sleep and emotional memory consolidation in a clinically depressed sample and the findings suggested a differential pattern of sleep-dependent memory consolidation in depressed and healthy adults. Implications and future directions for research are discussed. All rights reserved.
|Publication status||Published - 2016|
- Memory consolidation
- Sleep disturbance
- Major depression
- Theses and Dissertations
- Thesis (M.Soc.Sc(Psy))--The Education University of Hong Kong, 2016.