This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Sleep-Wake Disorders, Subject name: Psychiatry
Narcolepsy is due to abnormality in - 
Select and explain. 
A. Hypothalamus, B. Neocortex, C. Cerebellum, D. Medullaoblongata
A: Hypothalamus
Answer: A: Hypothalamus 
Explanation: Ans. is 'a' i.e., Hypothalamus o Narcolepsy is unique in that those who suffer from it typically fall almost instantaneously into REM sleep,o It is thought that narcolepsy is caused by a malfunctioning of the hypothalamus in brain.