The prenatal brain readiness for speech processing: A review on foetal development of auditory and primordial language networks

• Published in: Neuroscience and biobehavioral reviews Vol. 128; pp. 709 - 719
• Main Authors: Ghio, Marta, Cara, Cristina, Tettamanti, Marco
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2021
• Subjects: Auditory processing; Brain networks; Foetal brain development; Language acquisition; Speech processing; Brain networks; Foetal brain development; Language acquisition; Speech processing; Auditory processing
• ISSN: 0149-7634; 1873-7528
• DOI: 10.1016/j.neubiorev.2021.07.009

•Auditory network’s anatomo-functional development is complete in foetuses at term.•A primordial language-related network reaches maturation by the end of gestation.•Foetuses respond to auditory and speech stimuli.•Exact brain mechanisms for prenatal speech processing readiness are still unknown. Despite consolidated evidence for the prenatal ability to elaborate and respond to sounds and speech stimuli, the ontogenetic functional brain maturation of language responsiveness in the foetus is still poorly understood. Recent advances in in-vivo foetal neuroimaging have contributed to a finely detailed picture of the anatomo-functional hallmarks that define the prenatal neurodevelopment of auditory and language-related networks. Here, we first outline available evidence for the prenatal development of auditory and language-related brain structures and of their anatomical connections. Second, we focus on functional connectivity data showing the emergence of auditory and primordial language networks in the foetal brain. Third, we recapitulate functional neuroimaging studies assessing the prenatal readiness for sound processing, as a crucial prerequisite for the foetus to experientially respond to spoken language. In conclusion, we suggest that the state of the art has reached sufficient maturity to directly assess the neural mechanisms underlying the prenatal readiness for speech processing and to evaluate whether foetal neuromarkers can predict the postnatal development of language acquisition abilities and disabilities.