The delayed emergence of lexical morphology in preterm children: the case of verbs

A linguistic analysis in low-risk preterm (PT) children was conducted to determine whether the acquisition of complex aspects of the lexicon, such as verbs, was influenced by their premature birth status and whether sociocultural factors played a modulating role in this aspect of cognitive development. Fifty-one PT children, distributed in three birthweight groups - extremely low (780-1200 g), very low (1201-1500 g) and low (1501-2210 g)-were evaluated at 42 months and 60 months of age to assess their production of main, auxiliary and non-finite verb types and tokens relative to that of two control groups of fullterm children matched for age and socioeconomic level. The children's verb lexicon was collected during a 20-min controlled play context, Analyses of transcript data revealed first that the effect of sociocultural variables was independent of birth status or age. Further analyses revealed significant differences, indicating a marked increase in both verb type and token usage in the control children, whereas verb production in the three groups of PT children remained generally poorer. The data suggest that impaired language development is a cognitive consequence of prematurity independently of birthweight. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.