Early Indications of Delayed Cognitive Development in Preschool Children Born very Preterm: Evidence from Domain-General and Domain-Specific Tasks

Cognitive impairment often follows preterm birth but its early underlying nature is not well understood. We used a novel approach by investigating the development of colour cognition in 54 very preterm children born <= 30 weeks gestational age without severe neurosensory impairment and 37 age-matched term-born controls, aged 2-5 years. Quantitative and qualitative differences in the development of colour cognition are well charted throughout the preschool years, enabling delayed from deviant development to be determined. Standardized domain-general and experimental colour-specific tests of language, attention, and memory were employed. Very preterm children showed significantly depressed language than term controls, with very preterm group girls significantly outperforming boys. Very preterm children also showed poorer attention and memory than term controls, but not significantly so. Importantly, colour-specific tests showed qualitatively similar performance, but for naming and executive planning quantitatively poorer performance, across groups, indicating typical but delayed development. Hence, even before school entry, compared with term-born peers, very preterm children show delayed development of cognitive processes that underpin later scholastic abilities, but the nature by which these processes operate appears to be typical of term children. If left untreated these early developmental delays may underpin later deviations from the typical developmental trajectory. Copyright (C) 2010 John Wiley & Sons, Ltd.