There are three components to the definition of a delusion:
A delusion is usually, but not always, a false belief.
A delusional belief may dominate the life of the patient e.g. a persecutory delusion may prevent the patient leaving their home. Alternatively, the patient may appear unmoved by what would seem to be a terrifying belief, this picture is most common in patients with chronic schizophrenia.
Delusions may be primary or secondary.
Last reviewed 01/2018