Current research on neural mechanisms of learning and memory is revealing neurochemical and neuroanatomical changes that may store memories. These changes occur at the synaptic junctions, which are the functional contacts between neurons. Various drugs can either improve or impair the formation of memory. In experimental animals, full development of the brain and of behavioral capacity require experience that is enriched beyond the level of the standard colony environment. Enriched experience also serves as therapy for brain damage. Advances in science and medicine, coupled with a lowered birthrate, should reduce the incidence of mental retardation markedly by the end of the century, but special educators do not seem to be aware of this impending change.
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