While this blog is aimed primarily at cancer, including prevention, management, and what you can do to reduce risk, today my mind wanders to the subject of memory. Historically, the connection between poor sleep, memory loss, and brain deterioration as we age has been elusive. But, scientists at the University of California, Berkeley (USA) have discovered a link between these hallmark maladies of old age, opening the door to boosting the quality of sleep in order to improve memory.
Researchers found that slow brain waves generated during the deep, restorative sleep we typically experience in youth play a key role in transporting memories from the hippocampus – which provides very short-term storage for memories – to you prefrontal cortex, our brain’s longer-term “hard drive.”
Background: Healthy adults typically spend one-quarter of the night in deep, non-rapid-eye-movement (REM) sleep. Slowwaves are generated by the brain’s middle frontal lobe. Deterioration of this frontal region of the brain in elderly people is lined to their failure to generate deep sleep.
The Study: Researchers tested the memories of 18 healthy young adults (mostly in their 20s) and 15 healthy older adults (mostly in their 70s) after a full night’s sleep. Before going to bed, participants learned and were tested on 120 word sets that taxed their memories. As they slept, an EEG machine measured their brain wave activity. The next morning, they were tested again on the word pairs (but this time while undergoing functional and structural brain imaging (fMRI, or functional Magnetic Resonance Imaging).
Results: Among older adults, results showed a clear link between the degree of brain deterioration in the middle frontal lobe and the severity of impaired “slow wave activity” during sleep. On average, the quality of deep sleep among older adults was 75 percent lower than that of the younger participants, and the memory of the word pairs the next day was 55 percent worse among older participants. Among young adults, brain scans showed that deep sleep had efficiently helped to shift their memories to the long-term storage of the prefrontal cortex.
Yes, But Can We Do Anything About It? Maybe. For example, in a German study conducted earlier, neuroscientists successfully used neurostimulation of the brain in young adults to enhance deep sleep and doubled their overnight memory. UC Berkeley researchers will be trying the same trick among older adults. I’m Dr. Michael Hunter, and that’s you memory update.
Reference: Unviersity of California 0f Berkeley (2013, January 27). Poor sleep in old age prevents the brain fro storing memories. ScienceDaily. Retrieved January 15, 2014 from http://www.sciencedaily.com/releases/2013/01/130127134212.htm