Most people of a certain age are all too familiar with "senior moments" of forgetfulness; now scientists may have figured out why. Age-related changes in brain structure disrupt deep, particularly slow-wave, sleep, which scientists believe contributes to memory impairment. Evidence from studies of younger adults suggests that the amount of slow-wave sleep is directly associated with memory retention.

Adults are known to get worse at memory tasks as they get older, and aging is correlated with the deterioration of certain areas of the brain that generate these slow waves. Researchers reasoned there might be a connection.

Unlike the memory-impairing degeneration of neurons in the brain or blood clots and other vascular problems behind strokes, for which no treatments exists, sleep can be manipulated.

"What probably surprised me was the strength of the association between age-related changes in the brain and sleep, and the impact of the disruption of sleep on memory," Bryce Mander, a postdoctoral fellow in the department of psychology at UC Berkeley, tells TheDoctor.

If this strong connection between disruptions in slow-wave sleep and memory loss in the elderly does indeed contribute to memory loss, it could be very good news because sleep quality is something that you can improve. "It is," says Mander, "a hopeful target." Unlike the memory-impairing degeneration of neurons in the brain or blood clots and other vascular problems that cause strokes for which no treatments exist, sleep can be manipulated.

One of the easiest ways to get deep sleep is behavioral — if you get more exercise during the day, you will have a deeper sleep at night, according to Dr. Mander, who also emphasizes the need to pay attention to sleep hygiene. That means having a regular sleep schedule and minimizing any distractions. "Make sure that your bedroom is cool, dark, and comfortable, and go to sleep at the same time consistently, and the deep sleep that you do have will not be disrupted further." Better sleep hygiene will not necessarily enhance the quality of your deep sleep, but it will improve your sleep overall, says Mander. You will wake up less often and have a more restorative sleep.

The researchers are curious to see if this relationship holds true for older persons with memory disorders. "We know that those with memory disorders have a sleep that is even more disrupted than that of healthy older persons," Dr. Mander reports. If so, is sleep disruption predictive of memory symptoms? Can something be done to improve the sleep of those with memory disorders, and does that improve their symptoms? The study was published online recently in the journal Nature Neuroscience.