The Role of GABA in Human Motor Learning

TLDR

GABA modification plays an important role in motor cortical plasticity. We hypothesized that individual differences in GABA system responsiveness to modification influence learning capacity in healthy adults. GABA responsiveness was assessed by transcranial direct current stimulation, an intervention known to decrease GABA. The magnitude of M1 GABA decrease induced by anodal tDCS correlated positively with both motor learning performance and fMRI signal change in left M1, indicating that GABAergic responsiveness predicts short‑term motor learning behavior and related brain activity.

Abstract

GABA modification plays an important role in motor cortical plasticity. We therefore hypothesized that interindividual variation in the responsiveness of the GABA system to modification influences learning capacity in healthy adults. We assessed GABA responsiveness by transcranial direct current stimulation (tDCS), an intervention known to decrease GABA. The magnitude of M1 GABA decrease induced by anodal tDCS correlated positively with both the degree of motor learning and the degree of fMRI signal change within the left M1 during learning. This study therefore suggests that the responsiveness of the GABAergic system to modification may be relevant to short-term motor learning behavior and learning-related brain activity.