New Delhi: A recent study conducted by US-based scientists has found that poor sleep affects people of different age groups differently. More importantly, it indicates that older women show changes that are associated with memory loss and resemble early signs of Alzheimer’s disease.
Researchers at State University of New York at Binghamton looked at brain scans and sleep data of over 1,300 participants to determine how poor sleep impacts communication between different areas of the brain. The study, published in Neurobiology of Aging, shows that sleep deprivation may not affect everyone equally. It states that the brain’s response to sleep loss is strongly influenced by age, and in some cases, biological sex.
Younger adults who don’t get enough sleep tend to show increased neural activity, while older adults show changes in the brain’s networks associated with cognition and memory. The researchers found that younger adults who slept poorly had increased connectivity between the brain’s centres for attention and movement. Their brains were hyperactive and in a continuous state of preparedness. They could not reach a restful state, so they could not relax completely to fall asleep. This may have to do with contemplation, or repetitive negative thoughts, before sleep, the study pointed out.
Sleep deprivation affects seniors differently
But the pattern was quite different for people aged 65 and older, who had lower connectivity in the brain’s motor-related regions. At the same time, changes were seen in the brain’s networks that control memory, attention, and other cognitive processes— suggesting that poor sleep may result in more widespread changes with age.
One of the most significant results was observed among older women, who showed increased connectivity between the Default Mode Network, which is linked to memory and introspection, and the Frontal Parietal Network, the brain’s executive control centre. Participants exhibiting this pattern did poorly on memory tests. Similar connectivity patterns have been observed in preclinical stages of Alzheimer’s disease.
Although no causal inferences can be made, these findings provide preliminary evidence that sleep-related changes in brain connectivity may be early indicators of declining cerebral health.
The study also raises important questions about causality, such as “Is it poor sleep that induces neural changes, or do pre-existing brain changes predispose to sleep problems?” Further studies are needed to explain this relationship.
The present findings, however, highlight that sleep problems should not be viewed as a universal problem across all age groups. For younger adults, interventions to reduce cognitive hyperactivity before sleep may be beneficial. Meanwhile, older adults, especially women, who have chronic sleep problems should be evaluated by a medical professional.
This study is part of an expanding body of research that indicates that good quality sleep may be important to protect the aging brain.
(Edited by Aakriti Handa)