Sulcal Polymorphisms of the IFC and ACC Contribute to Inhibitory Control Variability in Children and Adults

International audienceInhibitory control (IC) is a core executive function that enables humans to resist habits, temptations, or distractions. IC efficiency in childhood is a strong predictor of academic and professional success later in life. Based on analysis of the sulcal pattern, a qualitative feature of cortex anatomy determined during fetal life and stable during development, we searched for evidence that interindividual differences in IC partly trace back to prenatal processes. Using anatomical magnetic resonance imaging (MRI), we analyzed the sulcal pattern of two key regions of the IC neural network, the dorsal anterior cingulate cortex (ACC) and the inferior frontal cortex (IFC), which limits the inferior frontal gyrus. We found that the sulcal pattern asymmetry of both the ACC and IFC contributes to IC (Stroop score) in children and adults: participants with asymmetrical ACC or IFC sulcal patterns had better IC efficiency than participants with symmetrical ACC or IFC sulcal patterns. Such additive effects of IFC and ACC sulcal patterns on IC efficiency suggest that distinct early neurodevelopmental mechanisms targeting different brain regions likely contribute to IC efficiency. This view shares some analogies with the " common variant–small effect " model in genetics, which states that frequent genetic polymorphisms have small effects but collectively account for a large portion of the variance. Similarly, each sulcal polymorphism has a small but additive effect: IFC and ACC sulcal patterns, respectively, explained 3% and 14% of the variance of the Stroop interference scores. Significance Statement Inhibitory control (IC) is a cognitive function that plays a critical role in the pathophysiology of several psychiatric conditions and in academic and professional success. Using anatomical magnetic resonance imaging (MRI) of healthy children and adults, we found that IC efficiency is constrained by the morphology (sulcal pattern) of two key regions of the neural network underlying IC. Because the sulcal pattern is a morphologic feature of cortical anatomy that is determined during fetal life and stable during development, our findings provide evidence that interindividual differences in IC partly trace back to prenatal processes and that distinct early neurodevelopmental mechanisms targeting different brain regions likely contribute to IC efficiency