The health breakthrough shows that slow brain waves generated during deep sleep play a key role in transporting memories around the brainâmore specifically, transporting them from the hippocampus (short-term memory) to the prefrontal cortexâs longer-term âhard drive.â
But in older adults, memories might get stuck in the hippocampusâcaused by poor quality of deep sleep. Then, the memories are overwritten by new memories. This helps explain the relationship between brain deterioration, sleep disruption, and memory loss as we get older. And it also sheds light on why older adults tend to be more forgetful, especially with names.
Healthy adults typically spend one-quarter of the night in deep sleep. Slow waves emanate from the brainâs middle frontal lobe. Deterioration of this frontal region of the brain in elderly people is linked to a lack of deep sleep.
The new study involved 18 healthy young adults and 15 healthy older adults in their 70s. Before going to bed, participants learned and were tested on 120 word sets that taxed their memories. At night, researchers measured brain waves. In the morning, they were tested again on the word pairs.
On average, the quality of older adultsâ deep sleep was 75% lower than the younger adults, and their memory of the word pairs the next day was 55% worse.
RECOMMENDED: Memory problems also linked to prescription drugs.
The studyâs results may pave the way to therapeutic treatments for memory lossâenabling the brain to more easily recharge while in deep sleep. Electrical stimulation is one example, which can be used on the brain safely in order to enhance deep sleep. Doctors Health Press has covered this therapy, called transcutaneous electrical nerve stimulation (TENS).
Sources for Today’s Articles:
Why Poor Sleep Hurts Your Memory
Mander, B., et al., âPrefrontal atrophy, disrupted NREM slow waves and impaired hippocampal-dependent memory in aging,â Nature Neuroscience, published online January 27, 2013.