Parent-infant interaction in the context of emerging neurodiversities: Neurofibromatosis 1 and elevated likelihood of ADHD

Neurofibromatosis 1 (NF1) and attention-deficit hyperactivity disorder (ADHD) are distinct conditions with similarities in developmental course. Research suggests that neurodivergent processes in both conditions begin in the first year, altering infant behaviour and how parents respond, over time reducing social-communicative opportunities for social brain development. This study aimed to investigate parent-infant interactions in both groups relative to typically developing infants (TD) at 10 and 14 months. We hypothesised that the infants with NF1 and infants at elevated likelihood of ADHD (EL-ADHD) would show less attentiveness to their parent and less mutual parent-infant interaction relative to TD controls, that attentiveness-to-parent would be particularly low in infants with NF1, and that liveliness and negative affect would be higher in infants with EL-ADHD. Parents and their infants with NF1, EL-ADHD and TD were videotaped during free play interactions and coded using validated rating scales. The two non-TD groups differed in their interactive patterns from the TD group and each other in ways somewhat consistent with the early behaviours that characterise each group. The NF1 group showed relatively less mutual interactions than the EL-ADHD group, and less parental sensitive responsiveness and parental directiveness than the TD group, while EL-ADHD infants were livelier and showed less negative affect relative to the other groups. Most main effects persisted over time. While longer-term follow-up in larger samples is needed, our findings highlight how children with neurodevelopmental conditions that are not primarily characterised by social communication difficulties may nonetheless come to have distinct social experiences in the first year of life.