Poor Sleep in Old Age Causes Memory Loss

A new study shows a strong association between poor sleep, memory loss and brain deterioration in older people.

The study, conducted by researchers at the University of California, Berkeley, has for the first time devised a link between these hallmarks of old age. This study therefore highlights the necessity of boosting sleep in elderly people in order to improve their memory.

According to the study, older people have a poorer memory when compared to the youth, because the slow brain waves generated during deep sleep helps in transferring memory from the short-term to the long-term memory. But in older adults, the information is stuck in the short-term memory due to lack of sleep. These slow waves in older people are soon occupied by new events.

"What we have discovered is a dysfunctional pathway that helps explain the relationship between brain deterioration, sleep disruption and memory loss as we get older - and with that, a potentially new treatment avenue," UC Berkeley sleep researcher Matthew Walker, an associate professor of psychology and neuroscience at UC Berkeley and senior author of the study, said in a press statement.

It is reported that healthy adults spend one-quarter of the night in deep, non-rapid-eye-movement (REM) sleep. Slow waves that are generated in the frontal region get deteriorated, as elderly people suffer with lack of sleep.

A sleep-enhancing test was conducted on older people to check if their memory improved overnight. The memory of 18 healthy young adults and 15 older adults was tested after a complete night's sleep. The mean age of the young group was 20 and that of the older adults was 70. Before sleeping, they were tested on 120 word sets.

Their brain activity was measured during sleep with the help of an electroencephalographic (EEG) machine. The next day, the groups were tested in the word pairs again.

On conducting the study, researchers noticed that the older adults scored 55 percent less on the memory test that was conducting after sleeping. When compared to the younger participants, the quality of their deep sleep was 75 percent less.

Dr. Simon Ridley, from the charity Alzheimer's Research UK was quoted in Belfast Telegraph as stating, "This small study makes a link between structural changes in the brain, sleep quality and memory in old age, but further investigation is needed to confirm the nature of this association."

The study details were published in the journal Nature Neuroscience.