While sleeping properly improves memory and learning capacities in young and middle-aged people, for those 70 years and older, the correlation between sleeping and memory becomes weaker. Those are the conclusions from recent research conducted at Baylor University, and recently published in the Perspectives on Psychological Science journal, which raised a series of questions regarding the benefits that sleeping has on memory throughout a person’s life.
The director of Baylor’s Sleep Neuroscience and Cognition Laboratory, Michael K. Scullin, Ph.D., was the researcher responsible for the study, in which 50 years of sleep were analyzed in participants. Scullin believes that his findings, published in the article “Sleep, Cognition, and Normal Aging: Integrating a Half Century of Multidisciplinary Research,” raised an “alluring question,” according to a press release from Baylor.
“If sleep benefits memory and thinking in young adults but is changed in quantity and quality with age, then the question is whether improving sleep might delay, or reverse, age-related changes in memory and thinking,” said Scullin. “It’s the difference between investing up front rather than trying to compensate later. We came across studies that showed that sleeping well in middle age predicted better mental functioning 28 years later.”
Scullin, who is also an assistant professor of psychology and neuroscience in Baylor’s College of Arts & Sciences, along with study co-author Donald Bliwise, Ph.D., a professor of neurology at Emory University School of Medicine, has found that the benefits from a sound night’s sleep in young adults are observed in a wide, diverse group of subjects.
Deep sleep, or slow-(brain)-wave-sleep in younger patients, for instance, improves memory, as it strengthens and recollects better parts of the experiences from the day by replaying them. In addition, middle-aged patients also improve their memory and avoid impairment, by sleeping more during the daytime, in afternoon naps for example. However, the nighttime sleep must be preserved.
The research included about 200 studies that began in 1967, and evaluated both sleep and mental function in patients who were categorized as young between the ages 18 to 29, middle-aged from 30 to 60, and old who were more than 60 years old. Patients reported the number of hours they usually sleep, the time needed to fall asleep, the frequency of times they wake up during the night and the sense of sleepiness felt during the day. In addition, scientists linked results from brain-wave studies and experiments on sleep deprivation, napping and sleep intervention like medications.
Sleep disorders are common in Americans, and sleeping has been analyzed by several studies and researchers, unrevealing it to be a determinant for overall health. Among those studies is one conducted by Robert Rosenberg, which connects sleep to the development of inflammatory bowel diseases (IBD). In addition, a UTHSC researcher revealed that the lack of sleep may activate depressive genes, while another research suggested its influence in the development of heart diseases.