Cortico-cerebellar network involved in saccade adaptation.

Saccade adaptation is the learning process that ensures that vision and saccades remain calibrated. The central nervous system network involved in these adaptive processes remains unclear because of difficulties in isolating the learning process from the correlated visual and motor processes. Here we imaged the human brain during a novel saccade adaptation paradigm that allowed us to isolate neural signals involved in learning independent of the changes in the amplitude of corrective saccades usually correlated with adaptation. We show that the changes in activation in the ipsiversive cerebellar vermis that track adaptation are not driven by the changes in corrective saccades and thus provide critical supporting evidence for previous findings. Similarly, we find that activation in the dorsomedial wall of the contraversive precuneus mirrors the pattern found in the cerebellum. Finally, we identify dorsolateral and dorsomedial cortical areas in the frontal and parietal lobes that encode the retinal errors following inaccurate saccades used to drive recalibration. Together, these data identify a distributed network of cerebellar and cortical areas and their specific roles in oculomotor learning. NEW & NOTEWORTHY The central nervous system constantly learns from errors and adapts to keep visual targets and saccades in registration. We imaged the human brain while the gain of saccades adapted to a visual target that was displaced while the eye was in motion, inducing retinal error. Activity in the cerebellum and precuneus tracked learning, whereas parts of the dorsolateral and dorsomedial frontal and parietal cortex encoded the retinal error used to drive learning.