The Influence of Parenting Style on Neurocognitive Development of Children With an Extra X or Y Chromosome: A Prospective 1‐Year Follow‐Up Study

BACKGROUND: As sex chromosome trisomies (SCTs), including 47, XXX, 47, XXY, and 47, XYY, are associated with increased risk for neurodevelopmental challenges, studying SCTs may help in understanding the role of early parental caregiving in shaping neurodevelopmental phenotypes of this genetically at-risk population. OBJECTIVES: This prospective longitudinal 1-year follow-up study examined the early developmental trajectories of neurocognitive functions that are key to social development: expressive and receptive language, facial affect recognition, and theory of mind (ToM). In addition, the study investigated parenting behaviors, positive affect, involvement, sensitivity, intrusiveness, and regulation, as potential predictors of developmental trajectories. MATERIALS AND METHODS: Neurocognitive testing was performed in n = 42 children with SCTs (aged 3-7 years) and n = 55 children from the general population, over a 1-year period. Parenting behaviors were measured using structured behavior observations of parent-child interactions. RESULTS: Children with SCT demonstrated significant and persistent delays across all measured domains, with the largest deficits observed in expressive language. While both SCT and TD groups showed developmental gains over time, children with SCT improved more slowly in ToM and exhibited increasing divergence in facial affect recognition. Importantly, within the SCT group, higher levels of parental interest/involvement were associated with greater improvements in expressive language, and greater parental positive affect predicted better outcomes over time in facial affect recognition. DISCUSSION AND CONCLUSION: These findings suggest that SCT is associated with an early-emerging and stable neurodevelopmental vulnerability in language functioning and increasingly deviant social cognitive development. Parenting behaviors, particularly parental interest/involvement and positive affect, emerged as meaningful protective predictors of developmental progress in expressive language and facial affect recognition, respectively, underscoring the importance of early caregiving environments in shaping outcomes in this genetically at-risk population. The results underscore the need of early screening and the potential value of targeted, parent-mediated interventions.