Functional symptoms in neurology

IS IT YOUR JOB AS A NEUROLOGIST TO DEAL WITH THIS PROBLEM?

If you find people with “neurological symptoms but no disease” tiresome and not really what you came in to the specialty for, then you are going to find large parts of your job tiresome and—worse—your attitude will filter through in a negative way to the patients regardless of the form of words you use to talk to them. On the other hand, if you allow yourself to be interested by the complexity of the problem and can see the potential for benefit that you, as a neurologist, can make to some patients then you may discover that this is a worthwhile area in which to improve your knowledge and skills.

TERMINOLOGY

None of the current terms is perfect. It is best to choose words based on (a) how you see the cause or mechanism of the symptoms and (b) how this affects your ability to communicate the diagnosis helpfully to the patients (preferably also including copying your clinic letter to them). Ultimately the label is not as important as the neurologist’s attitude to the patient.

Psychiatric terminology

• Dissociative seizure/motor disorder (conversion disorder) (ICD-10) suggests dissociation as an important mechanism in symptom production, which is true for many patients but not all (see below). Dissociation has many meanings but in this context often refers to two particular experiences: depersonalisation, a feeling of disconnection from one’s own body, and derealisation, a feeling of disconnection from one’s environment (see Clinical approach, below).

• Conversion disorder (DSM-IV) is a relic of Freudian psychoanalytic theory in the American bible of psychiatry (DSM) based on the idea of conversion of mental distress to physical symptoms. It is defined as:

  • a motor or sensory symptom or blackouts not compatible with disease

  • which is not thought to be consciously manufactured

  • which causes distress and

  • is related to psychological factors.

Criteria 2 and …