This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
Hallucinations which occur at the 'start' of sleep is : 
Select and explain. 
A. Hypnagogic hallucinations, B. Hypnopompic hallucinations, C. Jactatio nocturna capitis, D. Non - specific hallucination
A: Hypnagogic hallucinations
Answer: A: Hypnagogic hallucinations 
Explanation: Hypnagogic hallucinations

These occur while “going” to sleep. Jactatio capitis nocturna, or rhythmic movement disorder is a neurological disorder characterized by involuntary movements, usually of head and neck, before and during the sleep.