Resting GABA concentration predicts inhibitory control during an auditory Go-Nogo task.

Inhibitory control plays an important role in goal-directed behavior. Although substantial inter-individual variability exists in the behavioral performance of response inhibition, the corresponding modulating neurochemical and neurophysiological mechanisms remain unclear. Thus, the present study aimed to explore the relationship between behavioral response inhibition, GABA+ concentrations and automatic sensory gating (SG) in the auditory cortices. We recruited 19 healthy adults to undergo magnetoencephalography, magnetic resonance spectroscopy (MRS), and behavioral experiments. A paired-stimulus paradigm was used to study SG of the auditory cortices, and an auditory-driven Go-Nogo task was used to evaluate the behavioral response inhibition. Resting GABA+ concentrations were measured in the bilateral superior temporal gyri by means of MRS. Neither GABA+ concentrations nor auditory SG showed significant hemispheric asymmetry. However, an enhanced SG (lower ratio) was found to correlate with improved behavioral inhibition. Moreover, a higher GABA+ concentration was strongly related to improved inhibitory control. These findings highlight the important role of automatic neurophysiological processes and inhibitory neurotransmitters in the prediction of the behavioral performance of inhibitory control.