Reinforcement of vocal correlates of auditory hallucinations by auditory feedback: a case study.

Although auditory hallucinations in schizophrenic patients are usually thought to be private events, several early writers observed vocalizations concurrent with hallucinations. The content of such vocalizations corresponded to what the voices were reported to have said. A schizophrenic patient is described whose whispers were increased to an intelligible level by the use of auditory feedback. This has implications for the self-control of hallucinations, and for neurological theories of verbal hallucinations.