John is blind and is therefore unable to detect the light that normally sets the suprachiasmatic nucleus (SCN). If he is like most blind people:
A) his sleep-wake, body temperature, and melatonin circadian rhythms may become desynchronized.
B) he will suffer from attacks of cataplexy, especially when he is emotionally aroused.
C) he will use sign language and tend to "sleep sign" during stage 4 NREM sleep when sleeptalking typically happens.
D) his REM sleep will consist of very vivid visual dreams, most of which will be lucid dreams.

Question

Quizplus · Accepted Answer

The suprachiasmatic nucleus (SCN) is responsible for regulating our circadian rhythms, which include sleep-wake cycles, body temperature, and melatonin secretion. Without input from light, the rhythms can become desynchronized, leading to sleep disturbances and other issues. Therefore, choice A is the best answer. Choice B is incorrect because cataplexy is a symptom of narcolepsy, not blindness. Choice C is incorrect because there is no evidence that blind people are more likely to use sign language or sleeptalk during stage 4 NREM sleep. Choice D is incorrect because blind people do not necessarily have more vivid visual dreams or more lucid dreams during REM sleep.

John Is Blind and Is Therefore Unable to Detect the Light