Prenatal learning relevant to early language development: A systematic review.

Newborns exhibit a wide array of perceptual abilities crucial for their language development, some of which may be learned prenatally. This systematic review aims to summarize the evidence regarding perceptual and neural abilities relevant to early language development that may be shaped by prenatal exposure to speech and other structured auditory input in typically developing populations. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method, 25 articles were included in the current study. The results suggest that prenatal exposure to speech shapes several perceptual and neural abilities relevant to early language development. These include recognition of the maternal language, sensitivity to rhythmic and prosodic characteristics of speech, processing of emotional prosody, sensitivity to vowels of the maternal language, and language-specific patterns of neural activation. To conclude, existing research suggests that prenatal exposure contributes to the emergence of several perceptual and neural abilities relevant to early language development, particularly those related to prosodic processing, maternal-language recognition, and vowel perception. However, important methodological shortcomings across the current literature, including small sample sizes, heterogeneity in experimental paradigms, and limited replication, reduce confidence in the robustness and generalizability of these findings. Future research using larger, well-powered, and methodologically rigorous studies is therefore needed to confirm, refine, and extend our understanding of prenatal learning in support of early language development.