Cerebellar acceleration of learning in an evidence-accumulation task.

Cerebellar processing contributes to sensory salience, cognition, and behavioral flexibility. Here, we report that learning on a sensory evidence-accumulation task in mice is accelerated by cue-locked optogenetic stimulation of Purkinje cells but not by continuous optogenetic interference. Latent-state analysis revealed that accelerated learning was associated with enhanced focus on current over past trials. A cerebellum-specific transgenic autism model with disrupted Purkinje cell function also unexpectedly showed accelerated learning as well as enhanced reactivity to touch and auditory cues. Transgenic mice and wild-type mice receiving cue-locked stimulation showed prolonged sensory responses in Purkinje cell complex spikes and anterior cingulate cortex, and a subset of Purkinje cells in crus I showed on-task enhanced response to stimuli in wild-type mice. Sensory salience and task state may be different facets of a complex-spike-based mechanism for regulating brain-wide learning mechanisms. These findings potentially link cerebellum-dependent sensory salience with a global weak coherence account of autism.