Semantic development of African-American children prenatally exposed to cocaine

Semantic content categories were described for the single word, multiple word, and verb relation utterances of 22 African-American 2-year-olds during a 90-min laboratory session. Half of the toddlers had been exposed prenatally to cocaine and half were unexposed, as documented by biological assay in the newborn period. The exposed and unexposed groups were carefully matched on demographic, medical, and proximal caregiving variables. Children's spontaneous utterances were transcribed from audio- and videotapes during the laboratory session and scored for semantic features by a team of reliable coders who were masked to child exposure status. General productive language features (utterance length, verbosity, and intelligibility) were also assessed. To evaluate general language and cognitive skills, the toddlers were evaluated with the Sequenced Inventory of Communicative Development-Revised (SICD-R) and the Bayley Scales of Infant Development (BSID). Although exposed and nonexposed toddlers exhibited similar sequences of semantic development, the exposed toddlers were more restricted and delayed in their semantic representations. No significant group differences were observed, however, for structural features of language (e.g., utterance length, distribution of utterance types) or for children's general language and cognitive functioning as assessed by standardized assessments (i.e., SICD-R, BSID). Thus, a history of prenatal cocaine exposure and associated risk factors (e.g., prenatal exposure to alcohol, diminished birth weight) are related to delays in early semantic development. Proposed diagnostic and treatment strategies are discussed.