26 Jan Sleep in Young Adults Important For Later Life Cognitive Function
MedicalResearch.com Interview with:
Michael K. Scullin, Ph.D.
Principal Investigator of the Sleep Neuroscience & Cognition (SNaC) Laboratory and an Assistant Professor of Psychology & Neuroscience Director Sleep Neuroscience and Cognition Laboratory Baylor University
Medical Research: What is the background for this study? What are the main findings?
Dr. Scullin: One of the purposes of sleep in healthy adults is to optimize cognitive functioning. When we lose out on a few hours of sleep we tend not to be able to focus or think as well as when we get enough sleep (typically 8 hours). Even more interesting is that particular aspects of sleep physiology—our deepest levels of sleep known as slow wave sleep and rapid eye movement sleep—are essential to our brain’s ability to take the information that we learn during the day and stabilize those memories so that we can use them in the future.
Sleep quantity and quality change markedly across the lifespan, though there are individual differences in how much one’s sleep changes. Our work was concerned with the possible long-term repercussions of cutting back on sleep and getting lower quality sleep (less slow wave sleep and rapid eye movement sleep). We reviewed approximately 200 scientific articles on this topic and we found that the amount of total sleep and the quality of that sleep is important to cognitive and memory functioning in young adults and middle-aged adults and can even predict how well someone’s cognitive functioning will be decades later. Thus, if you’re sleeping well when you are 40 then you are investing in preserving your mental functioning at age 50.
Medical Research: What should clinicians and patients take away from your report?
Dr. Scullin: Some of the most common symptoms of sleep disturbances include feeling sleepy during the day, snoring at night, and waking up repeatedly in the middle of the night to use the bathroom. Sleep problems should not be overlooked by either the clinician or the patient. Researchers have shown that not getting enough sleep can exacerbate medical conditions. In our work, we found that not sleeping enough and not getting enough rapid eye movement sleep could even predict how well one preserves their mental functioning as they move into older age. Clinicians and patients should be aware that there are many treatments for poor sleep, some that are pharmacological and others that involve simple habit changes. You can learn about many of these treatment options on the National Sleep Foundation’s website (http://sleepfoundation.org/).
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Scullin: One of the trickiest issues in the field is in determining why sleep quantity and quality change as we age. The answer is likely to that there are many factors contributing to the changes in sleep, with some factors having physiological origins such as changes to our internal biological clock, and other factors having psychological origins such as an increase in life stressors in middle age. My opinion is that if we can do a better job of isolating why sleep changes as we age then that will be the first step toward creating new interventions for maintaining sleep quality, and thus also cognitive functioning, across the lifespan.
Scullin, M. K. & Bliwise, D. L. (2015). Sleep, cognition, and normal aging: Integrating a half-century of multidisciplinary research. Perspectives on Psychological Science, 10, 97-137.