Perseveration is

(B) Repetition of word or a phrase > "Perseveration refers to a tendency to present with a point or theme, even after it has been dealt with exhaustively or the listener has tried to change the subject."> Perseveration is seen in schizophrenia3 but is not characteristic of this disorder.> It also seen in autistic disorders and few other psychosis. It is chracterised by repeatition of thoughts, speech or brief behavioural sequences without a sense of incompletion and not as a preventive or a corrective measure. This implies clearly that it is carried out without any purpose.