Phosphatase activity controls the ups and downs of cerebellar learning.

Investigations of the cellular substrate for cerebellar learning have focused largely on a single form of plasticity, kinase-dependent long-term depression (LTD). In this issue of Neuron, Schonewille et al. provide evidence that calcineurin, a protein phosphatase required for long-term potentiation (LTP) and other cellular processes, may be just as important. 2010 Elsevier Inc. All rights reserved.