a test used in the diagnosis of disease of the extrapyramidal or striatal system (e.g., parkinsonism, Wilson disease); with the patient supine and relaxed with attention diverted, the examiner briskly lifts the patient's head with the right hand and then allows it to drop on the palm of the examiner's left hand; the head of a normal person drops suddenly like a dead weight; in striatal disease the head falls slowly, gently, and almost hesitantly.