ABSTRACT
The human brain increases in size from about 400 g at term to 1400-1500 g at maturity, and the bulk of this growth occurs between birth and 2 years of age. This period of rapid brain growth, the ‘‘brain growth spurt,’’ begins about midgestation and does not slow perceptibly until about 18 months of age. Some further growth occurs after 2 years of age, but this is minor compared with the growth prior to 2 years of age; quantitatively, the increase in weight from 2 years of age to adulthood is about the same as that during the last half of pregnancy.
