BENTALL AND SLADE'S DEFINITION OF HALLUCINATIONS

   In 1988 the British psychologists Richard P. Ben-tall (b. 1956) and Peter D. Slade defined hallucinations as follows. "Any percept-like experience which (a) occurs in the absence of an appropriate stimulus, (b) has the full force or impact of the corresponding actual (real) perception, and (c) is not amenable to direct and voluntary control by the experiencer."

   References

   Slade, P.D., Bentall, R.P. (1988). Sensory deception. A scientific analysis of hallucination. London: Johns Hopkins University Press.