Guo, Guang (1998). The Timing of the Influences of Cumulative Poverty on Children's Cognitive Ability and Achievement. Social Forces, 77(1)
Is childhood such a critical period that, by the end of this period, cumulative poverty would have exerted maximum effect on children's cognitive outcomes? Or are cognitive outcomes more a function of the length of exposure to poverty regardless of the life stage in which the child is exposed to poverty? The NLSY, which measures each child's cognitive development repeatedly over time, was analyzed to answer these questions. We distinguish between ability and achievement. Ability is a more stable trait than achievement and tends to be determined by both environmental and genetic factors early in life. Achievement on the other hand is more acquired. This study shows that long-term poverty has substantial influences on both ability and achievement, but the time patterns of these influences are distinctly different. Childhood appears to be a much more crucial period for the development of cognitive ability than early adolescence. In contrast, poverty experienced in adolescence appears to be more influential to adolescent achievement than poverty experienced earlier in life.