Psychology Ph.D. student Emily Hokett will present a poster at the 143rd Annual Meeting of the American Neurological Association, which will be held on Oct. 21-23, 2018. Hokett's Ph.D. advisor is Audrey Duarte, associate professor in the School of Psychology and principal investigator of the Memory and Aging Lab.

TITLE
Age-Related Changes in Sleep Quality, Associative Memory, and Oscillatory Power

ABSTRACT
Research has shown that sleep is essential for memory consolidation. However, the effects of habitual sleep quality on memory performance are unclear, especially regarding age-related differences in brain function.

We hypothesized that sleep quality would be significantly related to retrieval-related EEG and memory performance across age groups. We investigated this relationship in young and older adults using one week of sleep data collection, a paired-associate memory task, and retrieval-related electroencephalography (EEG).

We found that memory accuracy was positively correlated with sleep quality across age groups. In addition, we found relationships between measures of sleep quality and measures of oscillatory power that supported memory performance.

For older adults, there was a negative trend for sleep fragmentation (SF) and retrieval-related theta synchronization for associative hits, an index of recollection-based memory. That is, lower SF was correlated with greater theta synchronization. Both SF and theta power correlated with memory accuracy such that lower SF and greater theta power supported better memory.

Moreover, we found a significant relationship across age with alpha desynchronization and memory accuracy. Alpha desynchronization has been found to be associated with memory retrieval. We also found trends that suggest a relationship between sleep quality and alpha desynchronization.

While our data suggests that sleep quality is important for memory performance in both young and older adults, older adults may be particularly sensitive to sleep quality. Prior research has shown that lifestyle factors such as maintaining good sleep quality and moderate physical activity may improve memory in older adults.

Consistent with these findings, we found that sleep quality was positively associated with associative memory. This study extends the current literature with the finding that good sleep quality may support greater functional activity in neural correlates important for memory accuracy.