Does neurodevelopmental load predict cognitive flexibility?

Introduction: Cognitive flexibility (CF) impairments are a hallmark of schizophrenia (SCZ), bipolar disorder (BD) and neurodevelopmental disorders (NDD). These impairments are associated with functional outcomes and are influenced by neurodevelopmental and neurodegenerative processes. Methods: A retrospective analysis of 135 clinical records (75 SCZ, 29 BD, 31 NDD) was conducted. CF impairments were assessed using the Trail Making Test part B (TMT-B), with impairments defined as scores ≤ -2 standard deviations (SD). Multiple linear regression was used to adjust for confounding factors. Results: Rates of CF impairments were significantly higher in NDD (64.5%) and SCZ (57.3%) groups compared to the BD group (34.5%). No significant difference was observed between NDD and SCZ groups. After adjusting for confounders, the mean education level emerged as the only significant factor influencing CF impairments. Discussion: Our findings suggest that CF impairments are transdiagnostic and influenced by the level of education. This highlights the importance of considering environmental and sociodemographic factors in cognitive outcomes and supports the interplay between neurodevelopmental and neurodegenerative models, where education would appear to mitigate the impact of early neurodevelopmental abnormalities and delaying cognitive decline. Conclusion: CF impairments are shaped by shared vulnerabilities across diagnostic categories, with the level education playing a critical role. Future research should explore longitudinal trajectories and neurobiological mechanisms underlying CF impairments to inform targeted interventions.