“Long-term but not short sleep time is associated with global cognition and specific cognitive abilities such as memory, visual-spatial skills and executive functions,”
Sudha Seshadri, founding director and senior author of the study at Biggs Institute. “These associations are stronger in people with symptoms of depression regardless of the use of antidepressants.”
The study highlights that too little and sleep can negatively affect brain function, especially in memory, attention and decision making. Experts recommend sleeping for 7 to 8 hours a night to protect your brain health.
Since depression often overlaps with sleep problems, 90% of people with depression reported sleep problems, researchers wanted to see how depression affects cognitive links to sleep.
Participants were grouped by their depression status and antidepressant use. Research found that those who sleep longer and suffer from symptoms of depression showed the greatest cognitive decline. The effect is weak, but it still exists in people without depression. Interestingly, people who take antidepressants but currently have no symptoms of depression do not show the same cognitive decline.
“Future longitudinal studies, including large-scale multimodal approaches, are to further elucidate the temporal relationship between sleep disorders and cognitive changes,” the researchers said.
