Is Motor Inhibition Mediated by Cerebello-cortical Interactions?

Motor inhibition is an essential skill for fully adapted behavior requiring motor control and higher-order functions of motor cognition. A wide set of cortical and subcortical areas, including the right inferior frontal gyrus, the pre-supplementary motor area, and the subthalamic nucleus in the basal ganglia, contribute to convey the inhibitory command to the motor cortex. In the present review, we discuss how recent evidence supports the idea that the cerebellum may also have a relevant contribution in certain aspects of motor inhibition. This evidence were provided by behavioral data collected in patients with cerebellar lesions, functional magnetic resonance (fMRI) investigations conducted in clinical samples and in healthy participants, and by transcranial magnetic stimulation (TMS) techniques used to non-invasively test cerebello-motor functional connectivity. The application of these methods, combined with the execution of inhibitory tasks, could provide new evidence for a causal role of the effective cerebello-cortical connectivity in motor inhibition. Understanding the neurophysiological mechanisms that mediate motor inhibition through the cerebellum could be essential to design new rehabilitative protocols for treating several neurological and psychiatric disorders characterized by disinhibited behavior such as addiction, schizophrenia, attention deficit hyperactivity disorder (ADHD) and Parkinson’s disease.