Do Blind People Have Difficulty Sleeping?

An estimated 80% of blind people have difficulty sleeping.

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.
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