Psychosis is a symptom of mental illness characterized by a radical change in personality and a distorted or diminished sense of objective reality.
Psychosis appears as a symptom of a number of mental disorders, including mood and personality disorders , schizophrenia , delusional disorder , and substance abuse. It is also the defining feature of the psychotic disorders (i.e., brief psychotic disorder , shared psychotic disorder , psychotic disorder due to a general medical condition, and substance-induced psychotic disorder ).
Patients suffering from psychosis are unable to distinguish the real from the unreal. They experience hallucinations and/or delusions that they believe are real, and they typically behave in an inappropriate and confused manner.
A mental illness can exhibited through various forms of psychosis, such as:
- Delusions. An unshakable and irrational belief in something untrue. Delusions defy normal reasoning, and remain firm even when overwhelming proof is presented to disprove them.
- Hallucinations. Psychosis causes false or distorted sensory experience that appear to be real. Psychotic patients often see, hear, smell, taste, or feel things that aren't there.
- Disorganized speech. Psychotic patients often speak incoherently, using noises instead of words and "talking" in unintelligible speech patterns.
- Disorganized or catatonic behavior. Behavior that is completely inappropriate to the situation or environment. Catatonic patients have either a complete lack of or inappropriate excess of motor activity. They can be completely rigid and unable to move (vegetative), or in constant motion. Disorganized behavior is unpredictable and inappropriate for a situation (such as screaming obscenities in the middle of class).
Paula Ford-Martin, M.A.