Cortical Excitability and Autonomic Regulation during Time-Based Motor Learning

Motor learning enables progressive performance improvement on repetitive tasks through adaptation and optimization of motor responses, allowing anticipation and accurate execution. This process can induce changes in cortical activity and autonomic regulation. We aimed to analyze how central and autonomic nervous system changes associate with time-based learning of a visuomotor decision-making task. Twenty-three participants (22.4±3 y, 10 male) completed 8 blocks of 40 trials, consisting of hitting a device target at a precise moment guided by a visual cue. The participants received performance feedback after each block to promote learning. Performance was evaluated across blocks to quantify motor learning. Resting-state EEG and ECG were recorded pre- and post-task to assess training-induced neurophysiological changes. Aperiodic brain activity was characterized by the 1/f exponent (assumed to reflect cortical excitability/inhibition balance), while autonomic activity was assessed through heart rate variability (HRV) as an index of parasympathetic modulation. Motor learning was positively associated with increased cortical excitability in frontal and left parietal regions, whereas increased HRV –reflecting parasympathetic predominance– correlated with increased cortical excitability in sensorimotor areas. These findings suggest that motor learning induces region-specific neurophysiological changes, with autonomic regulation selectively linked to sensorimotor cortical dynamics.