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.
Signs and symptoms vary, depending on the type of functional neurologic disorder, and may include specific patterns. Typically these disorders affect your movement or your senses, such as the ability to walk, swallow, see or hear. Symptoms can vary in severity and may come and go or be persistent. However, you can't intentionally produce or control your symptoms.
The cause of functional neurologic disorders is unknown. The condition may be triggered by a neurological disorder or by a reaction to stress or psychological or physical trauma, but that's not always the case. Functional neurologic disorders are related to how the brain functions, rather than damage to the brain's structure (such as from a stroke, multiple sclerosis, infection or injury).
Early diagnosis and treatment, especially education about the condition, can help with recovery.
Symptoms of functional neurologic disorders may vary, depending on the type of functional neurologic disorder, and they're significant enough to cause impairment and warrant medical evaluation. Symptoms can affect body movement and function and the senses.
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
When to see a doctor
Seek medical attention for signs and symptoms listed above. If the underlying cause is a neurological disease or another medical condition, quick diagnosis and treatment may be important. If the diagnosis is a functional neurologic disorder, treatment may improve the symptoms and help prevent future problems.
The exact cause of functional neurologic disorders is unknown. Theories regarding what happens in the brain to result in symptoms are complex and involve multiple mechanisms that may differ, depending on the type of functional neurologic disorder.
Basically, parts of the brain that control the functioning of your muscles and senses may be involved, even though no disease or abnormality exists.
Symptoms of functional neurologic disorders may appear suddenly after a stressful event, or with emotional or physical trauma. Other triggers may include changes or disruptions in how the brain functions at the structural, cellular or metabolic level. But the trigger for symptoms can't always be identified.
Factors that may increase your risk of functional neurologic disorders include:
- Having a neurological disease or disorder, such as epilepsy, migraines or a movement disorder
- Recent significant stress or emotional or physical trauma
- Having a mental health condition, such as a mood or anxiety disorder, dissociative disorder or certain personality disorders
- Having a family member with a functional neurologic disorder
- Possibly, having a history of physical or sexual abuse or neglect in childhood
Women may be more likely than men to develop functional neurologic disorders.
Some symptoms of functional neurologic disorders, particularly if not treated, can result in substantial disability and poor quality of life, similar to that caused by medical conditions or disease.
There are no standard tests for functional neurologic disorders. Diagnosis usually involves assessment of existing symptoms and ruling out any neurological or other medical condition that could cause the symptoms.
Functional neurologic disorders are diagnosed based on what is present, such as specific patterns of signs and symptoms, and not just by what is absent, such as a lack of structural changes on an MRI or abnormalities on an EEG.
Testing and diagnosis usually involves a neurologist, but may include a psychiatrist or other mental health professional. Your doctor may use any of these terms: functional neurologic disorders (FNDs), functional neurological symptom disorder or conversion disorder.
One advantage to using the term "functional neurologic disorders" is that it can be used to specify the type of functional neurological symptoms you have. For example, if your symptoms include problems walking, your doctor may refer to functional gait disorder or functional weakness.
Evaluation may include:
- Physical exam. Your doctor examines you and asks in-depth questions about your health and your signs and symptoms. Certain tests may eliminate medical disorders or neurological disease as the cause of your symptoms. Which tests you'll have depends on your signs and symptoms.
- Psychiatric exam. If appropriate, your neurologist may refer you to a mental health professional. He or she asks questions about your thoughts, feelings and behavior and discusses your symptoms. With your permission, information from family members or others may be helpful.
- Diagnostic criteria in the DSM-5. Your doctor may compare your symptoms to the criteria for diagnosis in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association.
DSM-5 lists these criteria for conversion disorder (functional neurological symptom disorder):
- One or more symptoms that affect body movement or your senses
- Symptoms can't be explained by a neurological or other medical condition or another mental health disorder
- Symptoms cause significant distress or problems in social, work or other areas, or they're significant enough that medical evaluation is recommended
Treatment will depend on your type of functional neurologic disorder and your particular signs and symptoms. For some people, a multispecialty team approach that includes a neurologist; psychiatrist or other mental health professional; speech, physical and occupational therapists; or others may be appropriate.
Learning about functional neurologic disorders
Understanding what functional neurologic disorders are, that the symptoms are real and that improvement is possible can help you with treatment choices and recovery. Symptoms may get better after an explanation of the condition and reassurance from your doctor that symptoms aren't caused by a serious underlying neurological or medical problem.
For some people, education and reassurance that they don't have a serious medical problem is the most effective treatment. For others, additional treatments may be beneficial. Involving loved ones can be helpful so that they can understand and support you.
Medical disorder treatment
Your medical team provides treatment of any medical or neurological disease you may have that might be a trigger for your symptoms.
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.
Mental health options
Even though functional neurological symptoms are not "all in your head," emotions and the way you think about things can have an impact on your symptoms and your recovery. Psychiatric treatment options may include:
- Cognitive behavioral therapy (CBT). A type of psychotherapy, CBT helps you become aware of inaccurate or negative thinking so that you can view situations more clearly and respond to them in a more effective way. CBT can also help you learn how to better manage stressful life situations and symptoms. This may be particularly beneficial if your symptoms include nonepileptic seizures. Other types of psychotherapy may be helpful if you have interpersonal problems or a history of trauma or abuse.
- Treating other mental health conditions. Anxiety, depression or other mental health disorders can worsen symptoms of functional neurologic disorders. Treating mental health conditions along with functional neurologic disorders can help recovery.
- Hypnosis. When done by a trained professional who is familiar with functional neurologic disorders, people who are receptive to suggestions during hypnosis may benefit if they have symptoms of a functional neurologic disorder that involve, for example, the loss of sensations or speech problems.
Medications are not effective for functional neurologic disorders, and no drugs are approved by the Food and Drug Administration specifically as a treatment. However, medications such as antidepressants may be helpful if you also have depression or other mood disorders, or you're having pain or insomnia.
Regular follow-up with your medical team is important to monitor your recovery and make changes to your treatment plan as needed.
You may start by seeing your primary care doctor. He or she may refer you to a neurologist. You may want to take a family member or friend along, if possible, to help you remember information and for support.
What you can do
To prepare for your appointment, make a list of:
- Any symptoms you're experiencing, including any that may seem unrelated to the reason for your appointment
- Key personal, family and social information, including any major stresses or recent life changes
- All medications, vitamins, herbs or other supplements you're taking, and the dosages
- Questions to ask your doctor to make the most of your time together
Some questions to ask your doctor include:
- What is likely causing my symptoms or condition?
- Are there other possible causes?
- What kinds of tests do I need?
- What treatment approach do you recommend?
- For how long will I need to be treated?
- What can I do to reduce the risk of my symptoms recurring?
- Should I see a specialist?
- If I need to take medications, what are the main side effects?
- Is there a generic alternative to the medicine you're prescribing?
- Are there any brochures or other printed material that I can have?
- What websites do you recommend?
Don't hesitate to ask other questions during your appointment.
What to expect from your doctor
Your doctor will likely ask you a number of questions. Be ready to answer them to reserve time to go over any points you want to spend more time on. Your doctor may ask:
- What are your symptoms?
- When did you first notice these symptoms?
- How have your symptoms changed over time?
- How do your symptoms impact your ability to function?
- What do you think may be causing your symptoms?
- Have you been diagnosed with any other medical conditions or mental health problems?
- Do you use alcohol or recreational drugs? How often?