Conversion disorder is a condition in which a person has blindness, paralysis, or other nervous system (neurologic) symptoms that cannot be explained.

Conversion disorder symptoms may occur because of emotional distress or psychological problems.

Symptoms usually begin suddenly after a stressful experience. People are more at risk for a conversion disorder if they also have a medical illness, dissociative disorder, or personality disorder.

Some doctors falsely believe that conversion disorder and similar disorders are not real conditions, and may tell patients that the problem is "all in your head." However, these conditions are real. They cause distress and cannot be turned on and off at will. Research on the mind-body connection may eventually increase understanding of these disorders.