Getting a good night’s sleep has all sorts of health benefits, while a bad night’s sleep can lead to health issues, from aging skin to weight gain. But these effects seem less drastic in light of a study published last month in the journal Neurology. It showed that poor quality sleep is actually linked with wasting away of the brain, especially in those over 60 years old.
Researchers from University of Oxford and University of Oslo sampled 147 adults. The subjects ranged from 20-84 years old and encompassed a variety of physical activity levels, body mass index (BMI) and blood pressure levels.
Each subject completed a questionnaire that measured sleep quality. The questionnaire assessed three main things: sleep latency (how long it takes to fall asleep), sleep duration (how many hours of sleep per night) and sleep efficiency (the percentage of time spent actually sleeping).
Two MRI scans were done for each subject, an average of 3.5 years apart, to see how different sleep habits affected the brain. After comparing brain volumes from the two scans, the researchers found that physical activity, BMI and blood pressure were not related to brain volume.
However, poor sleep quality was related to reduced brain volume, specifically in the cerebral cortex.
The cerebral cortex is the site of complex functions of the brain, and controls how we think and interact with the world. According to the study, lack of sleep may shrink part of the frontal cortex, which deals with problem-solving, self-control, planning and logic. Lack of sleep also accelerates the rate of brain loss in regions that process sound, language and spatial orientation.