Transcranial Magnetic Stimulation to Elicit Changes in Motor Cortex Excitability during Haptic Training

摘要

Training of skilled movements leads to typical changes in motor evoked potentials (MEPs). To see how such changes are related to motor performance and hand preference, a goal-directed movement task was implemented on a haptic interface. Both hands of right-handed subjects were trained separately in two sessions. Transcranial magnetic stimulation (TMS) was applied contralaterally to the trained hand before and after each session. Effects of right hand training: after session #1 MEP-facilitation was 60 %, intracortical inhibition (ICI) and facilitation (ICF) were reduced and task improvement was 37%. Left hand training: after session #1 MEP-facilitation was +59%, ICI and ICF remained unchanged and task improvement was +30%. During session #2 all variables for both sides remained constant. The different time course of the training-induced effects for the left and right hemisphere obviously reflects functional side differences in hand motor control.