Trial Outcomes & Findings for Priming Expectations and Motor Learning With tDCS (NCT NCT06039605)

Priming Expectations and Motor Learning With tDCS

This will be calculated as the average of two trials of the motor task that are completed one week after the last training session. The motor task is a timed test that requires participants to spoon two beans (kidney, raw) at a time from a center proximal "start" cup to three distal "target" cups as fast as possible. In short, this task requires multijoint coordination and limb reversal, and performance for each trial is measured in seconds.

This outcome measure will be measured as the slope of the line fitted to the motor task performance across all 30 training trials (this includes Day 1, 2 and 3), when trial is transformed to a logarithmic scale. This transformation is done to account for the fact that change in performance is non-linear. The motor task is a timed test that requires participants to spoon two beans (kidney, raw) at a time from a center proximal "start" cup to three distal "target" cups as fast as possible. In short, this task requires multijoint coordination and limb reversal, and performance for each trial is measured in seconds.

This will be the change (Day 1 minus Day 10) in expectations of tDCS. The tDCS expectation scores are taken from a 1-item survey adapted from the Expectation Assessment Scale, where scores range from 0 (no expectation) to 8 (high expectations); a score of 4 is considered neutral.

This is the average amount of time spent in the home cup for each repetition, averaged across the two follow-up trials.

his is the average peak velocity for the outward portion of each repetition, averaged across the two follow-up trials.

This is the coefficient of variation (CV) for tDCS expectation scores. It is calculated by dividing the standard deviation of the participant's expectations across study days (Days 1, 2, 3, and 10) by the mean expectation of these 4 study days. The tDCS expectation scores are taken from a 1-item survey adapted from the Expectation Assessment Scale, where scores range from 0 (no expectation) to 8 (high expectations); a score of 4 is considered neutral.

This is calculated using a 14-item self-rated questionnaire, with answers for each item ranging from 1 ("absent") to 10 ("severe"). A daily average score (ranging from 1 to 10) was calculated for each participant by averaging the 14 items. The reported values represent the mean of these daily averages per group. Higher values represent more severe symptoms (a worse outcome).

The tDCS expectation scores are taken from a 1-item survey adapted from the Expectation Assessment Scale, where scores range from 0 (no expectation) to 8 (high expectations); a score of 4 is considered neutral. This score was collected for each participant in the experimental group (tDCS1, tDCS2, tDCS3) across study days (Days 1, 2, 3, and 10).