Do the blind have any differences with their sleeping cycles than sighted people? How do their bodies get the cue to get sleepy without the perception of light and dark? And also, what about dreams? Does a person blind since birth “see” anything while dreaming?
I’m not sure why I’m responding to another blind person thread, I don’t have any expertise on the topic. Anyway, a day/night cycle is not required for people to sleep. They sleep because their body is tired. One of the initial challenges with a new born baby is to try and adjust their sleeping patterns to be in sync with the day/night cycle. Having just been in the womb for 9 months and with no light cues they’ve been sleeping whenever they feel like it. A blind person could do that if they wanted to (same as anyone else could,) however they’re going to have a daily activity routine like any sighted person and will base their sleep around that.
As to the dreams of the blind, http://www.straightdope.com/columns/read/534/what-are-the-dreams-of-the-blind-like The answer from Cecil himself.
SSG Schwartz