Functional Neurologic Disorder
What is Functional Neurologic Disorder?
Functional neurologic disorders — a newer and broader term that includes what some people call conversion disorder — feature nervous system (neurological) symptoms that can’t be explained by a neurological disease or other medical condition. However, the symptoms are real and cause significant distress or problems functioning.
What are the symptoms of Functional Neurologic Disorder?
Symptoms of functional neurologic disorders may vary, depending on the type of functional neurologic disorder.
Signs and symptoms that affect body movement and function may include:
- Weakness or paralysis
- Abnormal movement, such as tremors or difficulty walking
- Loss of balance
- Difficulty swallowing or feeling “a lump in the throat”
- Seizures or episodes of shaking and apparent loss of consciousness (nonepileptic seizures)
- Episodes of unresponsiveness
Signs and symptoms that affect the senses may include:
- Numbness or loss of the touch sensation
- Speech problems, such as inability to speak or slurred speech
- Vision problems, such as double vision or blindness
- Hearing problems or deafness
What causes Functional Neurologic Disorder?
The exact cause of functional neurologic disorder is unknown, although ongoing research is starting to provide suggestions as to how and why it develops. Many different predisposing factors can make patients more susceptible to functional neurologic disorder such as having another neurological condition, experiencing chronic pain, fatigue or stress.
However, some people with functional neurologic disorder have none of these risk factors.
How is Functional Neurologic Disorder diagnosed?
There are no standard tests for functional neurologic disorders.
It can be diagnosed on the basis of positive physical signs, and usually requires a neurologist or a doctor familiar with neurological diagnosis. Some examples of these signs are:
- Hoover’s test is for of functional leg weakness – the patient may have difficulty pushing their “bad” leg down (hip extension), but when they are asked to lift up their “good” leg, movement in the “bad” leg returns transiently to normal
- The tremor entrainment test for functional tremor – this is when the shaking of an arm or leg becomes momentarily better when the person concentrates on copying a movement that the examiner makes
- Dissociative (non-epileptic) seizures can often be recognized by a trained health professional using a combination of typical features such as: an episode of violent limb thrashing in which the eyes remain closed, side-to-side head movements, or an event lasting longer than 5 minutes where the eyes are closed, hyperventilation during a shaking attack or tearfulness on recovery.
What are the treatments for Functional Neurologic Disorder?
Treatment will depend on your type of functional neurologic disorder and your particular signs and symptoms. For some people, a multi-specialty team approach that includes a neurologist; psychiatrist or other mental health professional; speech, physical and occupational therapists; or others may be appropriate.
Depending on your needs, therapies may include:
- Physical or occupational therapy. Working with a physical or occupational therapist may improve movement symptoms and prevent complications. For example, regular movement of arms or legs may ward off muscle tightness and weakness if you have paralysis or loss of mobility. Gradual increases in exercise may improve your ability to function.
- Speech therapy. If your symptoms include problems with speech or swallowing, working with a speech therapist (speech-language pathologist) may help.
- Stress reduction or distraction techniques. Stress reduction techniques can include methods such as progressive muscle relaxation, breathing exercises, physical activity and exercise. Distraction techniques can include music, talking to another person, or deliberately changing the way you walk or move.