Differential Cortical Pattern in Auditory Task Oddball Paradigm in Children Exposed to Alcohol during Pregnancy

Abstract The negative effects of fetal alcohol exposure on child development are well documented. This study investigated the electrophysiological processing of cortical level acoustic signals in a group of 21 children prenatally exposed to alcohol. Participants aged 13-14 years at the time of the study were recruited from a longitudinal cohort sample. The study employed an observational, cross-sectional blind design and participants were divided into two groups: with and without fetal exposure to alcohol. Neurophysiological measures recorded N1, P2, N2, P3, P3a, and P3b components using the Oddball paradigm. Our results showed that the mothers’ sociodemographic conditions at the time of birth, as well as the children’s birth weights were homogeneous between the groups, though the Apgar score was lower in the exposed group. The neurophysiological components that showed different results in the groups were P2 and P3a. P2 amplitude was higher in the midline central electrode (Cz) compared to the midline parietal electrode (Pz), demonstrating a group interaction for exposed children. For P3a there was an interaction of group and electrode position, and the exposed group showed higher amplitudes in Cz compared to the unexposed group. However, the Apgar score did not influence these results. In conclusion, children who had fetal exposure to alcohol presented electrophysiological recordings distinct from the control group. These differences occurred both in the P2 component – which reflects a bottom-up mechanism of auditory processing – as well as the P3a component, which may reflect the participation of supra-modal hearing mechanisms.