Abstract
Stable and efficient locomotion requires precise coordination of whole-body movements. Learned changes in interlimb coordination can be induced by exposure to a split-belt treadmill that imposes different speeds under each side of the body. Here we show that mice adapt to split-belt walking in a way that is remarkably similar to humans, suggesting that this form of locomotor learning is highly conserved across vertebrates. Like human learning, mouse locomotor adaptation is specific to measures of interlimb coordination, has spatial and temporal components that adapt at different rates, and is highly context-specific. Using a variety of approaches, we demonstrate that split-belt adaptation in mice specifically depends on intermediate cerebellum, but is insensitive to large lesions of cerebral cortex. Finally, cell-type specific chemogenetics combined with quantitative behavioral analysis reveal distinct neural circuit mechanisms underlying spatial vs. temporal components of locomotor adaptation.
