Conversion disorder is a psychological condition that causes symptoms that appear to be neurological, such as paralysis, speech impairment or tremors. It is a type of somatoform disorder. The Diagnostic and Statistical Manual, 4th Ed., (DSM-IV) offers several specific criteria for diagnosing conversion disorder, which include:
- There must be at least one symptom of sensory or motor impairment.
- Symptoms are not caused by neurological condition, physical disease or substance abuse.
- Symptoms are preceded by conflict or psychological stress.
- Symptoms are not better explained by somatization disorder or another psychological condition.
Conversion disorder is usually caused by a psychological reaction to a highly stressful event. The disorder does not necessarily develop right away, though, so it is important for the therapist to be told of all highly stressful events in the clients past.

