The Pathophysiology of Functional Neurological Disorders

• ClinicalTrials.gov Identifier: NCT02905877
• Recruitment Status: Completed
• First Posted: September 19, 2016
• Last Update Posted: March 27, 2020
• Sponsor: University College, London
• Information provided by (Responsible Party): University College, London

Study Description

Brief Summary:

Functional disorders, also called psychogenic or psychosomatic are very common, disabling and their costs to society are immense.

Functional movement disorders are abnormal, involuntary movements, that are illogical in terms of classic neurology. Intriguingly, they typically manifest when patients pay attention to them and disappear with distraction.

The investigators aim to further the understanding of the pathophysiological mechanisms underlying functional neurological disorders in order to improve treatment. In particular they aim to understand the effect of attention on movement in general, on functional neurological mechanisms and on the sense of agency (of subjective control) over a movement.

Patients with a functional neurological disorder, patients with an organic neurological disorder and healthy participants will perform simple tasks, such as reaching to a target, while additional tasks will manipulate their attention. The effects of these attentional manipulations will be analysed on several levels: movement performance, analysed by the kinematics and electromyography (EMG),and psychophysical measures, such as the sense of agency.

If the hypothesis turns out to be true, then changing the attentional focus could be used as a treatment in functional neurological disorders.

Condition or disease	Intervention/treatment
Functional Neurological Disorders	Other: Behavioural study

Study Design

• Study Type: Observational
• Actual Enrollment: 130 participants
• Observational Model: Other
• Time Perspective: Other
• Official Title: The Pathophysiology of Functional Neurological Disorders
• Actual Study Start Date: September 2016
• Actual Primary Completion Date: September 30, 2019
• Actual Study Completion Date: September 30, 2019

Groups and Cohorts

Group/Cohort	Intervention/treatment
Functional neurological disorders; Initially especially patients diagnosed with a functional tremor.	Other: Behavioural study; reaching studies and other behavioural studies.
Organic neurological disorders.; Initially especially patients diagnosed with a an organic action tremor (e.g. essential tremor or dystonic tremor).	Other: Behavioural study; reaching studies and other behavioural studies.
Healthy control; Healthy age matched controls	Other: Behavioural study; reaching studies and other behavioural studies.

Outcome Measures

Primary Outcome Measures :

1. Tremor severity, assessed by kinematics, under different attentional conditions [ Time Frame: 1 year ]

Secondary Outcome Measures :

1. Sense of agency, assessed by intentional binding, under different attentional conditions [ Time Frame: 1 year ]

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 80 Years (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes
• Sampling Method: Non-Probability Sample

Study Population

see below under inclusion criteria

Criteria

Inclusion Criteria:

• We will recruit three groups of participants:

  1. functional neurological disorders, e.g. functional tremor: diagnosed by a neurologist.
  2. organic counterpart of the functional neurological disorders, e.g. in the case of functional tremor, the organic counterpart would be organic tremor: presence of an organic tremor according to internationally recognised guidelines and diagnosed by a neurologist.
  3. healthy age-matched controls.

Exclusion Criteria

• Healthy Participants: Major neurological disorder.

All groups:

1. Age under 18 or over 80
2. Significant impairment in ability to give informed consent for study procedures due to significant cognitive impairment and/or inability to understand study literature,
3. very severe tremor
4. moderate or severe cognitive impairment

Contacts and Locations

Locations

United Kingdom

Institute of Neurology, University College London

London, United Kingdom, WC1N 3BG

Sponsors and Collaborators

University College, London

More Information

• Responsible Party: University College, London
• ClinicalTrials.gov Identifier: NCT02905877
• Other Study ID Numbers: 16/0275
• First Posted: September 19, 2016
• Last Update Posted: March 27, 2020
• Last Verified: March 2020

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

Additional relevant MeSH terms:

Nervous System Diseases; Conversion Disorder; Somatoform Disorders; Mental Disorders