Research
Older brains cope better with lack of sleep, says 911吃瓜 study
In news that will delight baby boomers worldwide, a new 911吃瓜 study suggests that brains in healthy older adults may cope better with a lack of sleep than younger adults.
The findings indicate that when faced with a loss of sleep, older brains are able to adapt and actually respond in an entirely different way compared to younger brains.
But far from being a licence for older adults to burn the midnight oil, researchers are keen to emphasize that good-quality sleep is vitally important for human health throughout the course of a lifetime.
The study, published in , looked at how only three hours of sleep affected brain networks in younger adults (20-30 years), compared with older adults (65-75 years).
Lead researcher, Josh Neudorf, an affiliate member of 911吃瓜鈥檚 Institute for Neuroscience and Neurotechnology, says: 鈥淲hat we found was quite striking in that older and younger brains actually responded in opposite ways to acute sleep loss.
鈥淐ertain connections in the brains of younger adults showed increased connectivity as a response to less sleep, while those same connections in the brains of older adults showed decreased connectivity.
鈥淭hat decrease in connectivity promotes more efficient modular connectivity for the brain as a whole. In other words, the brain is acting in a more efficient way to maintain cognitive function. In contrast, the increased connectivity in younger brains suggests the brain is having to work harder to maintain function.鈥�
While researchers measured brain activity, not cognitive performance, previous research has indicated that older adults are often less impaired by a single night of poor sleep than younger adults.
鈥淥lder adults tend to better handle the effects of poor sleep, whereas younger adults, as we know, have the common symptoms of decreased mood and cognitive ability following poor sleep,鈥� says Neudorf.
鈥淭his study tries to get at the heart of this difference 鈥� how does the older brain react to lost sleep.鈥�
There are a few different theories as to why the older brain reacts in an opposite way to a younger brain, one of which is the theory of compensation.
This is the idea that the aging brain reorganizes itself and uses different strategies to maintain function. By promoting reduced connectivity between certain brain regions, researchers believe that this enables the brain to function more efficiently.
鈥淭he quality of sleep starts to change and deteriorates somewhat in older adults,鈥� says Neudorf.
鈥淭he theory of compensation is the idea that older brains adapt or compensate for those changes."
Health risks linked to sleep loss
While brains may react to one or two nights of sleep loss in differing ways, depending on your age, researchers emphasize that chronic, long-term sleep loss is detrimental to brain health and cognitive ability.
Beyond the well-known short-term effects of irritability and diminished cognitive ability, the cumulative loss of sleep over the lifespan has the potential to increase the risk of cardiovascular disease, hypertension, diabetes, weight problems and colorectal cancer.
There is also a link between poor sleep and dementia, according to Brianne Kent, assistant professor of psychology, INN associate director, and Canada Research Chair in Translational Neuroscience and Dementia.
鈥淎 lot of sleep disruption could increase your risk of dementia,鈥� says Kent, a co-author of this study.
鈥淲hat we know is that there鈥檚 a protein called amyloid beta, which accumulates in the brain and causes these plaques in the brains of individuals who have dementia.
鈥淎myloid beta is this toxic protein, a waste product of your brain. These plaques accumulate for, on average, about 20 years before dementia starts.鈥�
Kent, who studies Alzheimer鈥檚 disease, the most common cause of dementia, adds: 鈥淒uring sleep, that protein is cleared out at a faster rate. So if you鈥檙e continuously missing sleep, then that protein and those plaques will accumulate at a faster rate.
鈥淣ot everyone who has poor sleep will get Alzheimer鈥檚 disease, but if you are somebody who has the predisposition for the disease, then missing sleep over time will drive the process.鈥�