Memory loss and old age have been linked for generations, yet no definite reason for the association has been truly given. New research from University of California, Berkeley found a connection between poor sleep and memory loss, according to Medical Xpress.
Scientists at the University of California have found a process of transferring memories from the hippocampus region of the brain, which is responsible for storing memories for a short period of time, to prefrontal cortex which helps in long term storage of memories, during deep sleep. Older adults often experience problems getting a good quality, undisturbed sleep which results in memories not being transferred from hippocampus to prefrontal cortex. This impacts negatively and memories remain in the hippocampus and overwritten by new memories, reports Medical Xpress.
"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," said UC Berkeley sleep researcher Matthew Walker, an associate professor of psychology and neuroscience at UC Berkeley and senior author of the study. "When we are young, we have deep sleep that helps the brain store and retain new facts and information. But as we get older, the quality of our sleep deteriorates and prevents those memories from being saved by the brain at night."
The study found that healthy young adults spend one-quarter of the night in deep, uninterrupted and non rapid eye movement (REM) sleep which helps in generating the slow brain waves and transferred accordingly to the prefrontal cortex. Unlike in older adults, due to interrupted sleep this process does not take place.
Understanding the cause for memory loss in older adults helps in providing accurate treatment. Previous studies used electrical stimulation of the brain to improve the quality of sleep in young adults. Similarly scientists at the UC Berkeley conducted sleep enhancing study in order to see any improvement in older adults' memory.
Bryce Mander, a postdoctoral fellow in psychology at UC Berkeley and lead author of this latest study, finds this new process of helping the older adults remember their memories by enhancing the quality of their sleep fascinating, reports Medical Xpress. Mander and his colleagues conducted the study which included 18 young healthy adults with a mean age of 20 years and 15 healthy older adults with mean age 70 years old.
Both the groups were given a 120 word test and were asked to memorize before a full night's sleep. Participants' brain activity was measured using an electroencephalographic (EEG) after both the groups fell asleep. On testing both the groups again in the morning to answer the test given the night before, younger adults performed 55 percent better in word pair test as they had a 75 percent better quality sleep than the older adults.
The study is published online in the journal Nature Neuroscience.
