This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Psychiatry
Narcolepsy is due to the abnormality in 
Select and explain. 
A. Hypothalamus, B. Neocoex, C. Cerebellum, D. Medulla oblongata
A: Hypothalamus
Answer: A: Hypothalamus 
Explanation: Narcolepsy: Types central nervous system dysfunction of sleep mechanisms, hypocretin dysfunction, and deficit With Cataplexy symptom tetrad (1) excessive daytime sleepiness (2) cataplexy** (3) sleep paralysis (4) hypnagogic hallucinations **Temporary sudden loss of muscle tone, causing weakness and immobilization onset second decade of life. Without Cataplexy trigger for cataplexy: Strong emotions(laughter and anger) Due To Medical Condition Nocturnal sleep-fragmented, considerable sleep disturbance is present (tumors or sarcoidosis of the hypothalamus, multiple sclerosis plaques affecting the hypothalamus, paraneoplastic syndromes) Treatment: scheduled naps, lifestyle adjustment, modafinil, SSRI Reference: P 2161 chap. 20 Sleep Disorders(Kaplan & Sadock's Comprehensive Textbook of Psychiatry, 9th Edition)