Effects of early institutionalization involving psychosocial deprivation on cognitive functioning 60 years later: Findings of the LifeStories project

BACKGROUND: Institutionalization involving psychosocial deprivation affects child development negatively. However, there are few longitudinal studies, and no prospective study has yet examined the consequences of institutionalization in late adulthood. OBJECTIVE: Investigating effects of psychosocial deprivation on cognitive functioning 60 years later. PARTICIPANTS AND SETTING: A population-based survey of institutionalized infants and toddlers was conducted in Switzerland from 1958 to 1961 (n = 387; Mage = 0.93 years, SD = 0.53, 48 % female, 48 % Swiss nationality). In parallel, a comparison group of 399 family-raised children were assessed (Mage = 0.85 years, SD = 0.50, 46 % female, 100 % Swiss nationality). Six decades later, data on cognitive functioning were collected for 88 of the institutionalized group (Mage = 62.63 years, SD = 1.32), and 148 of the comparison group (Mage = 65.06, SD = 1.32). METHODS: Standardized tests were used: the Brunet-Lézine Developmental Test in early childhood and a short form of the Wechsler Adult Intelligence Scale in late adulthood. RESULTS: Formerly institutionalized individuals scored lower on cognitive functioning (d = - 0.67, p < .001), with the greatest difference in working memory (d = -0.78, p < .001). Longer duration of institutionalization increased the risk of lower cognitive functioning, indicating a dose-response effect. Institutionalization's impact on adult cognitive functioning was mediated by early childhood developmental status but not by later educational attainment. CONCLUSIONS: This study confirms the early experience hypothesis, indicating that early life conditions have lasting effects on human development, even into late adulthood.