Cortical auditory evoked potentials in 1-month-old infants predict language outcomes at 12 months

The neurophysiological assessment of infants in their first developmental year can provide important information about the functional changes of the brain and supports the study of behavioral and developmental characteristics. Infants' cortical auditory evoked potentials (CAEPs) reflect cortical maturation and appear to predict subsequent language abilities. This study aimed to identify CAEP components to two auditory stimulus intensities in 1-month-old infants and to understand how these are associated with social interactive and self-regulatory behaviors. In addition, it examined whether CAEPs predicted developmental outcomes when infants were assessed at 12 months of age. At 1 month, P2 and N2 components were present for both auditory stimulus intensities, with an increased P2 amplitude being observed for the higher-intensity stimuli. We also observed that an increased P2 amplitude in the lower intensity predicted receptive and expressive language competencies at 12 months. These results are consistent with previous findings indicating an association between auditory processing and developmental outcomes in infants. This study suggests that specific auditory neurophysiological markers are associated with developmental outcomes in the first developmental year.
We would like to show our most gratitude to all the families and infants who participated in this study. We thank Pedro Hispano Hospital, particularly Dr. J. Lopes dos Santos, for all the kindness throughout the data collection process. We thank Maria de Góis-Eanes and Santiago Galdo-Álvarez for the contributions to this study. Furthermore, we thank Associação Viver a Ciência for the Simbiontes prize in 2013. This research was supported by Fundação Bial (grant number 42/08) and financed by Fundação para a Ciência e Tecnologia (FCT) under a PhD grant (reference SFRH/BD/68263/2010) and under a fellowship to post-doctoral students (SFRH/BPD/91440/2012). This study was conducted at the Psychology Research Centre (PSI/01662), School of Psychology, University of Minho, supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (Ref.: UIDB/PSI/01662/2020). Sara Cruz acknowledges the Centro de Investigação em Psicologia para o Desenvolvimento (CIPD) [The Psychology for Positive Development Research Center] (UID/PSI/04375), Lusíada University North, Porto, supported by national funds through the Portuguese Foundation for Science and Technology, I.P., and the Portuguese Ministry of Science, Technology and Higher Education (UID/PSI/04375/2019). Alberto Crego was supported by the FCT and the Portuguese Ministry of Science, Technology and Higher Education, within the Transitory Disposition of the Decree No. 57/2016, of 29 August, amended by Law No. 57/2017 of 19 July.