Early Adverse Experiences and the Developing Brain

Abstract

Children exposed to various forms of adversity early in life are at increased risk for a broad range of developmental difficulties, affecting both cognitive and emotional adjustment. We review a growing body of evidence suggesting that exposure to adverse circumstances affects the developing brain in ways that increase risk for a myriad of problems. We focus on two forms of adversity, one in which children are exposed to childhood maltreatment in family environments, and another in which children are exposed to extreme psychosocial deprivation in contexts of institutional rearing. We discuss ways in which each of these experiences represent violations of species-expected caregiving conditions, thereby imposing challenges to the developing brain. We also review emerging data pointing to the effectiveness of early intervention in remediating neurodevelopmental consequences associated with maltreatment or institutional rearing. We conclude by discussing implications of this work for public health efforts and highlight important directions for the field.

Figure 1

(a) Average total cortical gray matter volume in cubic centimeters (cm³) for the CAUG, FCG, and NIG. (b) Average total white matter volume in cubic centimeters (cm³) for the CAUG, FCG, and NIG.

Figure 2

(a) Axial diffusivity of the fornix crus in the CAUG, FCG, and NIG. (b) Mean diffusivity of the cingulum of the cingulate gyrus in the CAUG, FCG, and NIG (note: lower mean diffusivity is indicative of higher integrity).

Figure 3

Distribution of alpha power across the scalp for (a) care-as-usual group, (b) foster care group placed after 24 months, (c) foster care group placed before 24 months, and (d) never institutionalized group. This illustrates the timing effects of placement into a family following early institutionalization as reflected in alpha activity. Specifically, in the top left of the figure can be seen the brain activity of the care as usual group (CAUG; ie, institutionalized group). Note that this figure is identical to the figure to the right, which depicts the brain activity of children removed from institutional care and placed in family (foster) care after the age of 24 months. In contrast, the lower left figure reveals the brain activity of children removed from institutional care before 24 months, whereas the figure in the lower right represents the brain activity of the never institutionalized children.