Presents information on synaptic plasticity, particularly, on how the N-methyl-D-aspartate (NMDA) receptors are activated if they are involved in long-term depression, with reference to a study led by M. Casado, which appeared in the 2002 issue of "Neuron." Description of how cerebellar long-term depression (LTD) occurs; Information on the induction of LTD.