Prenatal Cocaine Exposure Impacts Language and Reading Into Late Adolescence: Behavioral and ERP Evidence

ABSTRACT

Extant research documents impaired language among children with prenatal cocaine exposure (PCE) relative to nondrug exposed (NDE) children, suggesting that cocaine alters development of neurobiological systems that support language. The current study examines behavioral and neural (electrophysiological) indices of language function in older adolescents. Specifically, we compare performance of PCE (N = 59) and NDE (N = 51) adolescents on a battery of cognitive and linguistic assessments that tap word reading, reading comprehension, semantic and grammatical processing, and IQ. In addition, we examine event related potential (ERP) responses in in a subset of these children across three experimental tasks that examine word level phonological processing (rhyme priming), word level semantic processing (semantic priming), and sentence level semantic processing (semantic anomaly). Findings reveal deficits across a number of reading and language assessments, after controlling for socioeconomic status and exposure to other substances. Additionally, ERP data reveal atypical orthography to phonology mapping (reduced N1/P2 response) and atypical rhyme and semantic processing (N400 response). These findings suggest that PCE continues to impact language and reading skills into the late teenage years.

Acknowledgment

This research was supported in part by funding from the National Institute on Drug Abuse (R21 DA030665).

Notes

1. It should be noted that dose-dependent findings can be difficult to interpret because they are often based on self-reported drug use.

2. For all analyses age, grade, SES and other drug use were entered as covariates.

3. It is rare to find a sample of pregnant women who use only cocaine during pregnancy. In this sample, the drug of addiction was cocaine; however, some of these women used some alcohol, smoked some cigarettes and some smoked marijuana, or a combination of these drugs during the prenatal period, see Table 1.

4. No parents or children self-reported a neurological disorder or developmental disability including dyslexia, specific language impairment, or specific reading comprehension deficit (S-RCD). We did not screen for ADHD, however, we excluded any participants on psychoactive medications.

5. All RAs who completed assessments at any time were blind to exposure status.