About 80% of blind people have difficulty sleeping, research shows. The brain generally processes the light that comes through the eyes in order to set the body’s circadian rhythm, or the 24-hour "clock" that regulates the person's waking and sleeping patterns. People who are not completely blind don’t tend to suffer as many sleep difficulties as those who are completely blind and have no ability so see light signals. The body’s inability to regulate its sleep cycle because of the lack of light signals is a sleep disorder known as non-24-hour wake disorder. It is estimated to affect as many as 95,000 Americans, most of whom are totally blind.
More about blindness :
- The average circadian rhythm for a totally blind person is 24.5 hours rather than the standard 24 hours.
- An estimated 1.3 million Americans are blind, and about 10% of them have no ability to see any light.
- Caucasians are nearly four times more likely to suffer from blindness than any other race, research shows.