CONTRIBUTION OF THE CEREBELLUM TO SUPRA-SECOND TIME PERCEPTION

Accurate estimation of time is fundamental to behavior, yet its neural basis remains unclear. The striatum has been proposed to function as a neural clock, as its population activity reliably correlates with performance in timing tasks. In contrast, although the cerebellum is well established in motor timing control, its contribution to temporal perception remains unresolved. Here, we trained mice to discriminate one-second (1 s) and three-second (3 s) visual cues and report their decisions by directional licking. When presented with visual cues of variable intervals, the choice probability for ‘short’ and ‘long’ follows a symmetrical psychometric curve, suggesting that mice could differentiate the durations based on prior knowledge. In vivo recordings from cerebellum exhibited task-related temporal dynamics that evolved systematically during the sample period, reflecting the encoding of elapsed time and upcoming decisions. Moreover, behavioral outcomes were influenced by cerebellar perturbation. Optogenetic stimulation delivered during the first second of the visual cue shifted the psychometric curve toward ‘short’ decisions and increased slope. In contrast, cerebellar stimulation during the later phase of 3 s trials impaired performance. Both electrophysiological and optogenetic data indicate that the cerebellum dynamically encodes temporal information at distinct task moments to guide ‘short’ or ‘long’ decisions. Together, these findings provide the first evidence that the cerebellum also plays a critical role in supra-second timing.