The field of molecular biology brings new understandings of the way the nervous system functions, the ways in which the brain develops, and the impact of the environment on that development. For example, brain development taking place before age one is more rapid and extensive than previously realized. The months immediately after birth are critical in terms of brain maturation. Children's early exposure to good nutrition, toys and stimulating interaction with others has a positive impact on children's brain functions at age 15, as compared to peers who lacked this early input, and the effects appear to be cumulative. The brain uses its experience with the world to refine the way it functions.
Early experiences are important in shaping the way the brain works.
Children who experience extreme stress in their earliest years are at greater risk for developing a variety of cognitive, behavioral and emotional difficulties. In sum, much of the brain is already formed at birth and, during the first two years of life, most of the growth of brain cells occurs, accompanied by the structuring of neural connections. Thus, providing opportunities for complex perceptual and motor experiences at an early age favorably affects various learning abilities in later life. Such opportunities can even compensate, at least partly, for deficits associated with early malnutrition. Other research continues to accumulate, indicating that the early years are critical in the development of intelligence, personality, and social behavior.