Conversion Disorder · What Is It, Causes, Diagnosis, and More

Conversion disorder, also known as functional neurological symptom disorder, is a condition where individuals experience blindness, paralysis, or other symptoms affecting the nervous system that no known physical or mental disorder can explain; in other words, the origin of their symptoms is unknown.

According to the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, or DSM-5, conversion disorder is classified under the category of “somatic symptom and related disorders,” formerly known as somatization or somatoform disorders. These conditions are characterized by recurrent unexplained physical symptoms that cause significant distress and impairment to an individual’s daily life. 

The exact cause of conversion disorder is currently unknown. However, it is thought to arise in response to stressful life events, including adverse childhood experiences and physical or emotional trauma. Conversion disorder may be impacted by an individual's affect and personality because, often, medical symptoms can trigger an emotional response.

Some symptoms may also be affected by learned behaviors, such as the association between being sick and attracting attention. This happens predominantly when an individual develops the condition in early childhood. In addition, somatic symptom disorders are often comorbid in individuals with a history of substance abuse and other mental health disorders, including anxiety, personality disorders, and depression.

Conversion disorder involves one or more neurologic symptoms related to voluntary movement or sensory function, like sight or hearing, which is a neurological or medical condition that cannot otherwise explain. Unlike malingering or factitious disorder, where symptoms are simulated or deliberately produced to achieve some secondary gain or external goal, conversion symptoms are real and often worsened because they cannot be scientifically explained.

Symptoms of conversion disorder include involuntary motor deficits, such as weakness or paralysis (e.g., a history of dropping things, dragging the leg when walking, etc.). A critical diagnostic finding in conversion weakness is that the deficit is inconsistent at different times in the examination. For example, one may report being unable to flex their feet when lying down but can walk on tip-toes when standing. In other cases, symptoms appear only in specific settings (i.e., one might feel unable to move their legs only when they are at school but have no trouble when they are home). 

Other symptoms of conversion disorder include sensory disturbances, like sensory loss or numbness; visual disturbances, such as blurred vision, double vision, or complete blindness; difficulty swallowing; and speech disturbances, such as functional dysphonia, which usually presents as whispering or hoarseness. Individuals may also experience psychogenic nonepileptic seizures, which are episodes of movement, sensation, or behaviors similar to epileptic seizures but do not have a neurologic origin.

In addition to conversion symptoms, individuals often report many current or prior physical symptoms or functional disorders, such as irritable bowel syndrome, fibromyalgia, or chronic fatigue syndrome. They may also report dissociative disorders, including depersonalization (i.e., feeling disconnected from oneself) and derealization (i.e., feeling detached from the environment), particularly at the onset of the disorder or in association with a nonepileptic seizure. 

Diagnosis of conversion disorder is typically made when an individual has one or more neurologic symptoms that any known medical condition cannot explain. Diagnostic tests are either normal or do not explain the individual’s symptoms. 

According to the DSM-5, diagnosis of conversion disorder requires the presence of one or more neurologic symptoms affecting voluntary motor or sensory function; clinical findings proving evidence of incompatibility between the reported symptom and any known medical condition; and symptoms that cause significant distress or impairment in the person’s quality of life. Finally, other diagnoses, such as malingering or factitious disorder, should be ruled out if the physician suspects the person is faking or producing the symptoms deliberately. 

Treatment of conversion disorder begins by establishing a trusting relationship between the individual and clinician. The clinician may want to empathize and focus on caring rather than curing, as the individual may want to feel understood and not dismissed. Individuals should also be seen at regularly scheduled intervals and tapered as they learn to cope with their condition. New health concerns and stressors may need to be explored, and each new complaint should be evaluated to ensure it is not due to organic disease. 

Psychotherapeutic interventions, such as cognitive–behavioral therapy (CBT), behavioral stress management, and psychoeducation, are aimed at helping individuals feel empowered by their symptoms. Individuals with conversion disorder often limit their activities based on their physical symptoms, so cognitive-behavioral therapy pushes them to go beyond these limits, to show them that they are capable of more, thereby improving their quality of life. Clinicians may also encourage individuals to take an active role in treatment by working on realistic goals with specific, observable behaviors, which may help them learn to avoid quickly assuming the sick role. Finally, antidepressant medications (e.g., SSRIs, like fluoxetine) can be used in individuals with comorbid anxiety or depressive disorders and those incapacitated by their disorder.

Conversion disorder, or functional neurological symptom disorder, is a condition where individuals experience neurologic symptoms that no underlying pathology can explain. Conversion disorder is often associated with stressful life events and other comorbid mental health disorders, including certain personality traits, anxiety, depression, or substance use disorders. Diagnosis of conversion disorder is based on clinical presentation, a thorough physician exam, and tests to rule out other causes of the symptoms. Treatment usually consists of empathy by the healthcare provider, psychotherapy, and antidepressant medications, in cases where individuals have comorbid mental health disorders or feel hindered by their disorder.