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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Narcolepsy is due to an abnormality in -
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The correct answer is  Narcolepsy is unique in that those who suffer from it typically fall almost instantaneously into REM sleep.
It is thought that narcolepsy is caused by a malfunctioning of the hypothalamus in the brain.