A cause of memory impairment rarely suspected

By Micha Shalev

When life’s challenges include memory loss or dementia, your perceptions, relationships and priorities inevitably shift. Changes to our sleep patterns naturally occur with aging, but scientists are finding links between changes in sleep with senior memory impairment, cognitive decline and even dementia.

When we get older we begin to forget things. That’s the common wisdom, anyway, and it’s not far from the truth.

It’s long been known that sleep plays a strong role in memory consolidation, but now, research is showing that age-related changes to the sleeping brain disrupt the normal pathways to memory formation, leading to that forgetfulness we associate with growing older. Some studies are even showing an increased risk of cognitive impairment and/or dementia linked with disrupted sleep patterns.

An exciting discovery scientists have made in the area of sleep and memory research is that there is a link between poor sleep and memory loss in the aging brain. Neuroscientists at the University of California, Berkeley, reported their findings in a recent study that compared memory retention in groups of younger adults and older adults. Conducted in 2012 and recently released in Nature Neuroscience, the study found that in elderly people, age-related deterioration of the prefrontal cortex region of the brain was associated with a failure to achieve the kind of deep, slow-wave sleep that helps the brain consolidate memories and information.

Though it may seem there’s nothing we can do about the inevitable changes that happen in our brains as we age, there is a hopeful angle to the outcome of recent researches. The researchers’  findings may help future studies pinpoint new treatment angles for age-related memory loss. In fact, scientists are already designing studies to determine whether enhancing sleep in older adults can improve their overnight memory retention.

There is another, more serious reason to tackle the problem of poor sleep in seniors: The risk of developing cognitive impairment or dementia later in life. Not only do people get less deep sleep as they get older, according to the National Institutes of Health, they are more likely to experience disruptions to their sleep schedule, suffer from insomnia or sleep apnea, or develop movement disorders like restless legs syndrome that keep them from getting a good night’s sleep. Scientists are now finding that some of these sleep disruptions are associated with impaired cognition and, in some cases, the later onset of dementia.

In the end, it’s important to remember that there is not a simple cause-and-effect relationship between sleep and dementia risk, or sleep and memory loss. The interactions between sleep, brain changes and cognitive impairment are complex, and just as there are many factors that cause changes in sleep as our loved ones get older, there are numerous causes for age-related mental decline. Getting a good night’s sleep is just one piece of the puzzle.

According to the spokesman for the Alzheimer’s Society, “A good night’s sleep is one of the pleasures of the life but, once again, past researches suggested that the quality and duration of sleep had been also linked to people’s cognitive health.”

It’s far too early to conclude that lack of sleep plays a causal role in dementia, but there is more evidence that getting enough quality sleep is an essential preventative health measure — which means that those at mid-life and older, who are experiencing sleep problems, should try to solve them.