Are anomalous perceptual experiences necessary for delusions?

J Nerv Ment Dis. 2008 Jan;196(1):3-8. doi: 10.1097/NMD.0b013e31815f6619.


Several theories of delusions suggest that anomalous perceptual experience is necessary for delusion formation. This study evaluated levels of anomalous perceptual experience in a large group of nonclinical participants from the general population (N = 337), a group of psychotic inpatients (N = 20), and 2 groups of hallucinating (N = 24) and nonhallucinating (N = 24) deluded patients. The aims of the study were to evaluate the hypothesis that pathological levels of anomalous perceptual experience were necessarily associated with delusions. Using the Cardiff Anomalous Perceptions Scale, the main finding was that as a group, nonhallucinating deluded patients were not significantly different from nonclinical participants on any of the anomalous perceptual experience indices. We conclude that anomalous perceptual experience, as measured by the Cardiff Anomalous Perceptions Scale, is not necessary for the presence of delusions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Bipolar Disorder / diagnosis*
  • Bipolar Disorder / psychology
  • Delusions / diagnosis*
  • Delusions / psychology
  • Female
  • Hallucinations / diagnosis*
  • Hallucinations / psychology
  • Hospitalization
  • Humans
  • Male
  • Middle Aged
  • Perceptual Disorders / diagnosis*
  • Perceptual Disorders / psychology
  • Psychiatric Status Rating Scales / statistics & numerical data
  • Psychometrics
  • Psychotic Disorders / diagnosis*
  • Psychotic Disorders / psychology
  • Reference Values
  • Schizophrenia / diagnosis*
  • Schizophrenic Psychology*