Brain State-dependent Stimulation to Improve Movement

Summary

Repetitive transcranial magnetic stimulation (rTMS) is a powerful tool to non-invasively modulate brain circuits, brain plasticity, and behavior. This proposal will test the hypothesis that controlling behavioral state during focal multi-day rTMS of a brain region involved in grasping movements will enhance the functional specificity of the neuromodulation action among distributed brain regions involved in voluntary motor control and concomitantly improve manual dexterity. Results from this study will be used to optimize rTMS therapy for individuals with neuromotor impairments by controlling behavioral state to improve the efficacy of rTMS treatment.

Healthy volunteers that qualify for this study will have motor skill assessments and basic neuromotor testing (using neurophysiology with TMS and functional Magnetic Resonance Imaging (fMRI) scans). Participants will be asked to come in for up to nine sessions that include 1 screening session, 5 consecutive daily rTMS sessions and 3 assessment sessions with resting-state and task-based fMRI, neurophysiology with TMS, and hand motor tasks over the course of 3-4 weeks.

Conditions

• Healthy

Interventions

DEVICE

TMS

A MagPro X100 magnetic stimulator with a 90mm figure-8 coil (MC-B70, MagVenture Inc.) will be utilized to deliver brain stimulation. All participants will receive five consecutive days of stimulation. The 3-minute session of intermittent Theta Burst Stimulation (iTBS) will consist of 10 bursts of high-frequency stimulation (a 2 s train of 3 biphasic waveform pulses at 50 Hz repeated every 200 ms at 80% AMT) repeated every 10 s for a total of 190 s (600 pulses) to the target area. The target area will be located using BrainSight2 neuronavigation system. The baseline structural scan obtained during the scan 1 will be utilized for this localization process.

BEHAVIORAL

Object directed grasping

Subjects will perform a precision grip with the right hand towards either a small or large target object positioned in front of them. The illumination of an LED (green or red) will instruct the subject to plan a precision grip towards either a small or large target object positioned in front of them. After \~1 second, the LED will extinguish and cue subjects to execute the intended object-directed hand action. The presentation of the visual stimuli will be synchronized with the iTBS stimulation, which will occur 800ms before the onset of every "GO" cue in order to modulate cortical activity during both the planning and execution phase of the action.

Sponsors & Collaborators

• National Institute of Neurological Disorders and Stroke (NINDS)

  collaborator NIH

• University of Michigan

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

50 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2022-02-15

Primary Completion

2023-05-31

Completion

2023-05-31

Countries

• United States

Study Locations