Mechanisms for motor timing in the cerebellar cortex

•Timing of conditional eyeblinks determined by pauses in cerebellar Purkinje cells.•Blink-controlling Purkinje cells learn to pause during eyeblink conditoning.•Conditional Purkinje cell pause responses are adaptively timed.•Timing of Purkinje cell pauses determined by intrinsic cellular mechanisms.•Conditional pause responses elicited by glutamate via mGluR7 activation.

In classical eyeblink conditioning a subject learns to blink to a previously neutral stimulus. This conditional response is timed to occur just before an air puff to the eye. The learning is known to depend on the cerebellar cortex where Purkinje cells respond with adaptively timed pauses in their spontaneous firing. The pauses in the inhibitory Purkinje cells cause disinhibition of the cerebellar nuclei, which elicit the overt blinks. The timing of a Purkinje cell response was previously thought to require a temporal code in the input signal but recent work suggests that the Purkinje cells can learn to time their responses through an intrinsic mechanism that is activated by metabotropic glutamate receptors (mGluR7).