Social Deprivation, Social–Emotional Behavior, and the Plasticity of Dopamine Function

Abstract

brain plasticity and social developmentThe notion of plasticity in relation to biological and behavioral development is not a new one. Even when very little was known about brain structure and function and long before the advent of modern molecular and neuroanatomical techniques, scientists recognized that the brain had the capacity to adapt and change in response to environmental input. Already in 1892, William James stressed the importance of brain plasticity in the organization of habits:Plasticity, then, in the wide sense of the word, means the possession of a structure weak enough to yield to an influence, but strong enough not to yield all at once. Each relatively stable phase of equilibrium in such a structure is marked by what we call a new set of habits. Organic matter, especially nervous tissue, seems endowed with a very extraordinary degree of plasticity of this sort; so that we may without hesitation lay down as our first proposition the following: that the phenomena of habit in living beings are due to plasticity of the organic materials of which their bodies are composed. (p. 2, italic original ( James, 1892)