Action Outcome Latencies as a Measure of Sense of Agency in Functional Movement Disorders.

NCT07302308 | Not Yet Recruiting

• 1 other identifier: Action outcome latencies
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Functional movement disorders (FMD) are among the most common neurological conditions seen in clinical practice, yet they are poorly understood and often misdiagnosed. Impaired self-agency, the sense of controlling one's actions, is a key feature of FMD. Studies using functional MRI have shown reduced activation and connectivity in the right inferior parietal lobule, a region associated with agency. The sense of agency consists of two components: the feeling of agency, which is an implicit, low-level sense of control over voluntary actions, and the judgment of agency, which is the conscious attribution of actions to oneself. While the feeling of agency is often measured using intentional binding tasks, judgment of agency is assessed using self-reported scales. While studies have explored intentional binding as a measure of implicit agency in FMD, few have systematically investigated judgment of agency. This study aims to fill this gap by introducing a novel approach that quantitatively evaluates judgment of agency in FMD patients using action-outcome latencies as an objective metric.

Conditions

Functional Movement Disorder

Keywords

functional movement disorder; sense of agency; judgment of agency

Outcome Measures

Primary Outcomes (2)

• SA Index

  Latencies values corresponding to positive ("YES") responses will be extracted. SA (Sense of Agency) Index will be computed by multiplying the 90th percentile latencies by the number of positive responses below this latency threshold and then dividing the result by the total number of responses (positive, negative and unsure) occurring below the same threshold.

  Day 1

• Latencies

  The 90th percentile of latency values among trials with positive ("YES") responses.

  Day 1

Study Arms (2)

Cases

Functional Movement Disorder

Controls

Healthy subjects

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

movement disorder clinic

You may qualify if:

• Diagnosed with clinically definite functional movement disorder
• Age \>18 years.
• Able to read and understand English.
• Age \>18 years.
• Able to read and understand English

You may not qualify if:

• Moderate to severe action tremor in the dominant hand limiting the ability to perform the task.
• Upper limb peripheral neuropathy.
• Unable to read and understand English.
• \. Unable to read and understand English.

Sponsors & Collaborators

• Western University, Canada: lead

Study Sites (1)

University Hospital

London, Ontario, N6A5A5, Canada

Location

MeSH Terms

Conditions

Conversion Disorder

Condition Hierarchy (Ancestors)

Somatoform Disorders; Mental Disorders

Central Study Contacts

Aditya Murgai, MBBS MD DM

CONTACT

15196633121; aditya.murgai@lhsc.on.ca

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: December 11, 2025
• First Posted: December 24, 2025
• Study Start: January 31, 2026
• Primary Completion (Estimated): January 31, 2028
• Study Completion (Estimated): January 31, 2028
• Last Updated: January 21, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)