Overview

• Distortions of perception based on external stimuli. Perceives things as different to usual, but accepts that they are not real or that things are perceived differently by others.

• • Interpretation

  • Complete illusions: inattention resulting in misinterpretating, such as misreading words in a newspaper
  • Affect illusions: related to a particular mood state, such as mistaking shadows for people when particularly anxious or paranoid
  • Pareidolia: vivid illusions without any effort required, such as interpreting the markings on a picture of burnt toast as the Virgin Mary
  • Tactile illusions - such as phantom limb syndrome in those who have undergone amputation

• • Significance

  • Generally benign, though particular mood states such as depression, anxiety, mania or delirium may trigger illusions.