The Ganser phenomenon consists of giving approximate answers to questions which can at times verge on the absurd (Q: "How many legs does a cow have?"; A: "Three"), also known as paralogia or vor-beireden. This may occur in psychiatric disease, such as depression, schizophrenia, and malingering, and sometimes in neurological disease (head injury, epilepsy). A Ganser syndrome of hallucinations, conversion disorder, cognitive disorientation and approximate answers is also described but of uncertain nosology.
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