Narrator: This is Science Today. As people age, they tend to have less consolidated sleep — getting up more easily and more often during the night. And while there is good data supporting the idea that as we age, we sleep a little less than when we were younger, there's still much to be learned. Dr. Louis Ptacek studies sleep phenotypes at his lab at the University of California, San Francisco.
Ptacek: We think that we're gaining some insights by studying the genetic forms of the early morning larks that we work with. So, we know that a third of 65-year olds wake up earlier, significantly earlier, statistically — we know that a third of 65-year olds wake up statistically significantly earlier and go to bed statistically significantly earlier than they did when they were young people. And while no one understands what the basis for this is, we have some ideas that we're interested in pursuing and it does appear to be a normal part of aging. So, my lab is interested, among other things, in what about the aging process that leads us to be more morning larkish as we get older.
Narrator: For Science Today, I'm Larissa Branin.