Sleep Changes Across the Lifespan: A Multidimensional Construct

CONFERENCE REPORTER

Jesse Cook, PhD, discusses the multi-dimensional aspects of sleep health, emphasizing the importance of duration, continuity, and satisfaction. He notes that sleep needs decrease with age, from 7 to 9 hours for young adults to 7 to 8 hours for older adults.¹

Cook discusses the normative nature of nighttime awakenings, emphasizing that waking up during the night is not a problem. Nightly awakenings are normal, with an average of 0 to 2 for younger adults and 1 to 3 for older adults. He noted the importance of not overly stressing about meeting sleep duration benchmarks, as it can actually have the opposite effect and can exacerbate insomnia. He encourages normalizing nighttime awakenings to reduce patient anxiety and improve overall sleep quality.

As we age, there is a reduction in slow wave sleep. Slow wave sleep is crucial for healthy aging, particularly in regulating the glymphatic system and clearing brain toxins. Deep, restorative sleep episodes are necessary for cognitive health and performance, he stressed.

Cook also briefly introduced the synaptic homeostasis hypothesis, which suggests that sleep plays a role in restabilizing synapses. Over-potentiated synapses can lead to poor cognitive performance, and sleep helps restore normal functioning.² He highlighted various aspects of cognitive performance affected by sleep, including reaction time, word finding, and vigilance. The most important thing is ensuring people get the best sleep possible to support healthy cognition and overall well-being.

Dr Cook is a postdoctoral fellow with a doctoral degree in clinical psychology from the University of Wisconsin-Madison. His research focuses on the intersection of sleep and mental health, with his primary program of research purposed to advance the classification, assessment, and treatment of unexplained hypersomnolence. He has additional research interests related to the strengths, limitations, and overall utility of wearable sleep tracking technology for research and clinical purposes, as well as the roles of sleep and circadian health in the performance and well-being of athletes.

References

1. About sleep. CDC. May 15, 2024. Accessed June 12, 2026. https://www.cdc.gov/sleep/about/index.html

2. Cirelli C. Sleep and synaptic changes. Curr Opin Neurobiol. 2013;23(5):841-846.