hallucination true George Gkoutos "Perception in the absence of a stimulus." [wikipedia:Hallucination] HP:0000738 2011-04-14T03:52:31Z Hallucinations in psychiatric disorders Hallucinations in psychiatric disorders are commonly complex phenomena involving multiple sensory modalities, in contrast to the elementary sensory hallucinations (colours/flashes of light, ringing/buzzing sounds etc) that occur in focal epileptic seizures. Complex hallucinations with hallucinations of seeing people or scenes, hearing voices or formed music and distortions of visual perception may occur as an uncommon manifestation of focal seizures. The episodic nature of these phenomena, together with the presence of other features of a seizure and the interval return to a normal baseline helps distinguish these events from psychiatric hallucinations. behavior_ontology Behavioral Disorder