In the context of the nervous system, this refers to the role of neuronal activity and sensory experience in the normal development and maintenance of neuronal anatomy and function. It can also apply to compensatory changes in the nervous system following perturbations at any stage in the life span. For the developmental geneticist, developmental plasticity might be defined as the property or ability of a given genotype to produce different phenotypes in response to distinct environmental conditions. In the past, in developmental (neuro-) psychology, the term was reserved for infant and childhood phases of development, and in particular with reference to the resilience of young children in recovering from brain insults. Evidence now strongly suggests that plasticity is a life-span property of the brain as long as the brain remains healthy through to old-age. This evidence is based on new neural connections continuing to be made (e.g., in the hippocampus) beyond the age of 70 in healthy individuals. Something approaching the term ‘plasticity’ seems to have been put forward by the zoologist Richard Woltereck (1877-1944) in 1909 with his notion of Reaktiosnormin, and the first to use the word ‘plasticity’ appears to have been the geneticist Herman Nilsson-Ehle (1873-1949) in 1914 to describe the non-unique relationship of the genotype to the phenotype that he considered to have general adaptive significance.
See Adaptation, Brain sparing, Determination, Equipotentiality, Ocular dominance columns, Plasticity (neural)