Improving Locomotor Learning With Brain Stimulation

Not Applicable

Completed

Interventions: Behavioral: Motor Imagery (MI)
Device: Active tDCS
Device: Sham tDCS

Brief Summary: The primary goal of this research was to assess the practicality and initial effectiveness of a motor imagery (MI) intervention combined with elements of action observation (AO), alongside active or sham transcranial direct current stimulation (tDCS) over the prefrontal cortex (PFC), on locomotor learning in healthy adults. Feasibility was determined by examining recruitment rates, participant engagement, and safety measures. The efficacy of the intervention was gauged by analyzing the time taken to complete tasks and changes in cerebral blood flow immediately after the intervention and one week later. The study was guided by three main hypotheses: (1) the intervention techniques would be well-received and safe for the participants; (2) compared to a control group, MI training would lead to better learning outcomes and retention of learning; (3) in comparison to the control and sham tDCS groups, active tDCS would result in superior learning outcomes and retention of learning.

Detailed Description: The study implemented a double-blind, randomized, controlled trial design. Participants were tested three times over 7 days. After study enrollment, the participants were randomly assigned to one of three groups: MIActive (receiving active tDCS stimulation and participating in MI protocol), MISham (receiving sham tDCS stimulation and participating in MI protocol), and Control (receiving no stimulation and participating in an unrelated video-watching task) by a research member not associated with data collection. Allocation ratio was 1:1:1 and a block randomization approach was employed to maintain an equal distribution of participants across the three groups throughout the study. Study participants and assessors were blinded to assignment of active or sham tDCS. The independent variables were time (pre, post, and retention trials) and group (MIActive, MISham and Control), and the dependent variables were time to completion of a complex obstacle course and the amount of change in oxygenated hemoglobin (ΔO2Hb) during performance of that task.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Failure to meet specific inclusion criteria
History or presence of any neurological disease
Low visual ability, operationally defined as visual acuity less than 20/70 on the standard eye chart
Extreme difficulty performing walking tasks due to low visual ability
Clinical judgment of the investigative team
Additionally, subjects who are determined to be at increased risk for adverse events during the tDCS procedure, as determined by the tDCS screening questionnaire

Arm && Interventions

Group	Intervention	Description
MI/Active tDCS	Motor Imagery (MI)	The participants received active tDCS current and participated in the Motor Imagery intervention.
MI/Active tDCS	Active tDCS	The participants received active tDCS current and participated in the Motor Imagery intervention.
MI/Sham tDCS	Motor Imagery (MI)	The participants received sham tDCS current and participated in the Motor Imagery intervention.
MI/Sham tDCS	Sham tDCS	The participants received sham tDCS current and participated in the Motor Imagery intervention.

Primary Outcome Measures

Name	Time	Method
Prefrontal Cortical Activity	Baseline to 1 week follow up	Functional near infrared spectroscopy (fNIRS) monitor (OctaMon by Artinis Medical Systems), changes in oxygenated hemoglobin concentration (O2Hb) relative to a baseline task
Adherence to Interventions	Baseline to 1 week follow up	number of sessions attended
Retention of Participants	Baseline to 1 week follow up	number of participants completing intervention and follow-up assessment
Adverse Events in Each Study Arm	Baseline to 1 week follow up	Number of unexpected and/or serious adverse events
Time to Completion	Baseline to 1 week follow up	Recorded time to complete the obstacle course

Secondary Outcome Measures

Name	Time	Method
Kinesthetic and Visual Imagery Questionnaire (KVIQ)	Baseline to 1 week follow up	The Kinesthetic and Visual Imagery Questionnaire (KVIQ-10) measures the ability to imagine movements. This test evaluates the subject's ability to see (visual imagery) and feel (kinesthetic imagery) movements. The KVIQ-10 total score ranges from 10 to 50 (visual and kinesthetic subscale scores each range from 5 to 25).The KVIQ consists of 10 items, (5 movements for each scale), each item being a separate movement followed by rating the ease or difficulty of generating those self-images on a 5-point Likert scale (where 1 = no image or sensation and 5 = Image as clear as seeing or as intense as executing the action). Higher scores reflect higher imagery abilities.