Written by Dr. Tim Nicholson (Maudsley Hospital and Institute of Psychiatry Psychology & Neuroscience, King’s College London, UK)
Psychological factors, and therefore psychological treatments, can be important to consider in FND. Traditional theories of FND propose that psychological factors (i.e. stressful life events either before symptom onset or in the more distant past) might be relevant to the development of FND. However, it has become clear that there are many patients for whom this is not the case – although psychological factors might still be relevant in such patients as they can develop significant distress, and even depression, as a result of living with severe and chronic disorder such as FND and in such cases this can be helped by psychological treatments. Furthermore, many patients can feel stigmatized by healthcare professionals because of their FND diagnosis as the condition is so poorly understood by many healthcare professionals – this lack of understanding can become a significant roadblock in their care. This experience can then become a form of ‘medical trauma’, taking on a life of its own, and potentially feed a cycle of symptoms and stress.
There is also growing evidence that emotions, and abnormalities of its processing, might be involved in causing FND, at least for some patients. Experiments looking at brain activity in FND (using ‘functional neuroimaging’ brain scans) suggest alterations in the activity of areas of the brain responsible for arousal and emotional processing, such as the amygdala (see Fig 1), and this might interfere with areas of the brain involved in initiating or planning movement such as the SMA (supplementary motor area)1,2,3. Furthermore there is some evidence that these changes might be related to stressful life events in some people4 (see Fig 2). Such studies suggest that emotions might be able to influence the ability to initiate or control the motor system and result in symptoms such as weakness or tremor.
Fig 1: Brain scan showing increased activation in the amygdala of FND patients in response to negative emotional faces1