A new study has shown that poor sleep quality and varying bedtimes; reduce the ability to recall information from the past in older adults. The finding was particularly significant for adults of African-American descent; reports the study. The research was publish earlier this month in the journal Frontiers in Human Neuroscience.

The study was titled, “Age and Race-Related Differences in Sleep Discontinuity Link; to Associative Memory Performance and Its Neural Underpinnings”and was support; by the National Science Foundation Graduate Research Fellowship. The team of researchers from Georgia Institute of Technology, Atlanta; explain that this was a pilot study which include 50 adults living in and around Atlanta. The findings demonstrate the importance of good quality sleep; in maintaining cognitive and memory functions.

Audrey Duarte, an associate professor in Georgia Tech’s School of Psychology led this study. She is the main investigator in the Memory and Aging Lab: The night-to-night variability in the older study participants; had a major impact on their performance in tests aim at evaluating episodic memory. The association between sleep and memory is know; but this study’s novelty is showing that the connection is particularly evident for older adults and black participants, regardless of age.”

Exploring the link between sleep quality and memory

The current study is the first to explore the effects of sleep quality on memory with respect to age; race, and ethnicity. Audrey Duarte and Emily Hokett (a Ph.D. student in the School of Psychology) conduct the study; which included 81 volunteers from Atlanta. Of all the participants, those who already have some cognitive decline are exclude from the study. The age range of the participants was in two groups younger ones age between 18 and 37 years; and older ones age between 56 and 76 years. Finally, 50 adults met all the selection criteria and are include in the study.

But we want to look at lifestyle factors to see how people sleep normally; and how their sleep patterns change over time. We want to know how sleep affected memory performance; how well they remember things and how well their brains function depending on how well they slept.” Emily Hokett The team provided accelerometers to the participants to measure their sleep duration; and quality over a period of seven nights. This devices are wore around the wrists.

Labs usually measure the quality of sleep in more detail by measuring the brain waves. However, labs are often for a single night and may not provide real life data, say the researchers. The devices use in this study, which was wore by the participants at home; therefore provided more detailed information regarding sleep quality.

After the monitoring sleep patterns, the volunteers were then sent to a Georgia Tech laboratory for an electroencephalography (EEG) to measure brain wave activity during a memory test. Participants were ask to recall a pair of words show to them earlier and it is found that most of the older adults show better performance in their memory tests when they have slept better.

Stress levels impacts

The researchers also measure stress levels in all the participants; to see if stress could be the underlying cause of this association. Hokett said, “The main factor that correlate with poor sleep quality in black participants was race-related stress. When participants had higher values on that measure of stress; they would also have greater sleep fragmentation, on average. We found a very significant relationship here.” There was also a wide difference in memory performance base on sleep quality among older adults.

Next, Duarte and Hokett plan to look at the effects of poor sleep patterns; on Alzheimer’s disease and dementia risk among adults. Duarte said, “In understanding normative aging; lifestyle factors are a good area to target because they are potential factors we can control. It’s been known for decades that important things are happening while you sleep with regard to memory consolidation; and strengthening of memories. Because we knew that sleep quality typically declines in normal aging, this was a prime target for study.”