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

Condition(s) studied

Study 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.

Eligibility

Primary outcome measure(s)

• SA Index — Day 1
  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.
• Latencies — Day 1
  The 90th percentile of latency values among trials with positive ("YES") responses.

Trial sites (1)

More Western University, Canada trials in Canada

Other trials for the same condition