More American adults say they have problems with sleepwalking.
That's the headline of a new study by Stanford University.

Researchers say they found more than eight million U-S adults experience sleepwalking -- that's about three-point-six percent of the population, and an increase over prior studies.

And nearly one out of three Americans say they've been caught sleepwalking at least once -- usually as children.

One possible factor -- the study found use of over-the-counter sleep aids increased the likelihood of sleepwalking in some adults.

Doctors say sleepwalking is usually harmless, though it can lead to injuries if sleepwalkers fall or run into obstacles.