Low weight at birth and unfavorable socioeconomic background: effects on language and fluid intelligence

Abstract

ABSTRACTLow birthweight (<2500 g), associated with low socioeconomic status, has a negative effect on cognition and development. This is especially true for fluid intelligence and language. This study aimed to examine and identify (1) fluid intelligence and language in low- and adequate-birthweight children in a low-income Brazilian neighborhood and (2) the environmental factors that could account for potential group differences. There were 100 children participated in the study, of whom 53 had low birthweight and 47 had adequate birthweight. The children completed a battery of tests for fluid cognition and language. Their socioeconomic background and home environment were explored through a caregiver questionnaire. The results indicated significant group differences in fluid intelligence but not in language. Environmental factors partially explained the results. The variables ‘years of preschool’ and ‘number of learning games/books’ predicted better test results. Furthermore, the children underperformed in naming speed but not in accuracy, and the low-birthweight children also underperformed in fluid intelligence. It is concluded that environmental factors affect both birthweight groups and may compromise child development.