Cortical Auditory Neural Responses to Speech and Communicative Functioning in Normocephalic Children With Prenatal Exposure to the Zika Virus

OBJECTIVES: Prenatal exposure to the Zika virus may have an adverse effect on communicative functioning in children, even in the absence of microcephaly associated with Congenital Zika Syndrome. This study characterized cortical auditory neural function and communication abilities in normocephalic children with and without prenatal Zika virus exposure. DESIGN: Cortical auditory evoked potentials were recorded in response to naturally spoken consonant-vowel syllables in 117 Brazilian children with prenatal exposure to the Zika virus (M age: 6.29 ± 0.42 years) and a comparison group of 90 non-exposed children (M age: 5.54 ± 0.95 years). Language and communication abilities in daily life were evaluated using a battery of standardized behavioral measures and caregiver reports. RESULTS: Caregivers of exposed children reported significantly lower than typical adaptive functioning in the communication and socialization domains. Cortical auditory evoked potential analyses identified earlier speech sound differentiation in the non-exposed controls than in the exposed group (P1 versus N2 response). Exploratory analyses controlling for multiple postnatal factors indicated that greater cortical N2 speech sound differentiation was associated with more adaptive communication abilities. CONCLUSIONS: Normocephalic children with prenatal exposure to the Zika virus may exhibit subtle differences in auditory processing of speech that are associated with less adaptive communicative functioning in daily life. These results highlight the value of longitudinal follow-up of children with prenatal virus exposures and the utility of auditory evoked potentials in assessing populations at risk for altered neurodevelopment.