Alterations in N400 During Semantic Discrimination in Children with Attention Deficit Hyperactivity Disorder-Combined Presentation and Asymptomatic Siblings

Attention deficit hyperactivity disorder (ADHD) is an alteration characterized by inattention, hyperactivity, and impulsivity. In this study, we searched for potential alterations in language discrimination during N400 recordings and lateralization of these anomalies. We performed this study in children with ADHD combined presentation (-C), their asymptomatic siblings, and controls. N400 was obtained during discrimination of semantically related and non-related words near the pars triangularis and pars opercularis in the frontal lobe and in the posterior superior temporal gyrus (pSTG) of both hemispheres. We found no differences in the reaction time or percentage of correct answers among children with ADHD-C, siblings, and controls. Children with ADHD-C had lower amplitude and delayed latency in the pars triangularis and pars opercularis mainly in the left hemisphere. Siblings also had delayed latency in N400 at the pars triangularis and opercularis in the left hemisphere. Children with ADHD-C also showed alteration in lateralization of N400 wave towards the right hemisphere. In conclusion, children with ADHD-C had lower amplitude and latency delay in the N400 wave compared to controls, as well as changes in hemispheric lateralization during semantically related word discrimination in language-related cortical sites. Siblings had intermediate values between children with ADHD-C and controls.