By Eric Nayup, RPh, PharmD
Functional Neurological Disorder (FND) is a group of common neurological movement disorders caused by an abnormality in how the brain receives and sends signals to the rest of the body.
While there is no significant structural damage in the brain, people with FND have a disconnection in the functioning of the nervous system that leads to a variety of unplanned physical, sensory and cognitive symptoms.
Symptoms of FND can vary from person to person and can generally be classified into two categories according to the National Institute of Health (NIH):
The first category of FND is psychogenic nonepileptic seizures (PNES).
It is a functional dissociative seizure where someone loses either awareness of, or their ability to interact with, their surroundings. It is caused by brain dysfunction and not by abnormal electrical signalling. A person with PNES may experience uncontrolled shaking, suddenly going motionless and being unresponsive to surroundings.
The second category of FND is a functional movement disorder where the movements of the body are affected. The symptoms may manifest as limb weakness, tremors, functional dystonia (muscle spasm and stiffness), gait disorder (walking affected), tics, and sudden involuntary twitching or jerking of a muscle group. In addition, speech, vision, hearing and sensory functions might also be affected.
For some people, FND symptoms are short-lived, whereas they may last for years for others.
While the exact cause of FND is not known, certain factors do appear to increase the risk of FND. These include psychological or sociological factors, such as early childhood trauma, emotional stress and anxiety, and dysfunctional family life.
There are no specific treatments for FND but there are medical options available for managing its symptoms. Physiotherapy may be helpful for those who are experiencing motor symptoms. Some may also benefit from occupational therapy and speech therapy.
Psychological therapy is another option: Cognitive Behavioural Therapy is most suggested for people with FND. It can help with symptoms like pain and non-epileptic attacks. Some patients also practice self-help; relaxation and mindfulness exercises can help reduce stress.