Neurophysiology of functional neurological disorder
Research type
Research Study
Full title
Neurophysiology of functional neurological disorder
IRAS ID
228017
Contact name
William Sedley
Contact email
Sponsor organisation
Newcastle upon Tyne Hospitals NHS Foundation Trust
Duration of Study in the UK
4 years, 0 months, 0 days
Research summary
Functional neurological disorders are commonly encountered by neurologists, comprising one of the most common diagnoses made. These occur where aspects of the nervous system (such as movement or sensation of part of the body) do not work properly, for reasons other than physical abnormality of the relevant part of the nervous system. For instance, patients may experience loss of movement and sensation on one side of the body, but have no evidence of a stroke. Medical tests, such as brain scans, are generally normal, and their role is to help rule out alternative diagnoses. The diagnosis is generally made from the patient history and examination findings, but can sometimes be challenging to make. For instance, if the major symptom is loss of sensation (which cannot be assessed objectively), or where functional disorders coexist with physical damage to the nervous system. The cause is unknown, but a prominent theory is that the brain makes incorrect and overly strong predictions at a subconscious level, and these override input from the senses or motor control centres. Presently this theory is unsupported by scientific evidence.
This study aims to measure brain responses to stimulation of sensory nerves in order to assess whether patients with functional sensory loss show evidence of inappropriate predictions of sensory input. Sensory stimulation is performed via a series of weak electrical impulses to the wrist or ankle, in a manner that is generally predictable, but with occasional unpredictable changes. Brain responses are recorded with electroencephalography (EEG) using electrical sensors on the scalp. By measuring particular electrical brain responses that indicate the violation of predictions, and comparing these to healthy controls, evidence of aberrant predictions will be sought.REC name
Wales REC 6
REC reference
17/WA/0266
Date of REC Opinion
14 Sep 2017
REC opinion
Further Information Favourable Opinion