July 27, 2011
Science Daily/Stanford University Medical Center
With the novel use of a technique that uses light to control brain cells, researchers have shown that fragmented sleep causes memory impairment in mice.
Until recently scientists have been unable to tease out the effects on the brain of different yet intertwined features of sleep. But these investigators were able to overcome that problem and come to their findings by using the novel method, known as optogenetics, to manipulate brain cells to affect just one aspect of sleep.
The study shows that "regardless of the total amount of sleep, a minimal unit of uninterrupted sleep is crucial for memory consolidation," the authors write in the study that will be published online July 25 in the Proceedings of the National Academy of Sciences.
While the study does not reach any conclusions about the amount of sleep needed to avoid memory impairment in humans, it does suggest that memory difficulties in people with apnea and other sleep disorders are likely connected to the compromised continuity of sleep caused by such conditions.