Boys are more sensitive to environmental factors like parental behavior, an important predictor of executive function. This study examined whether the interaction between child sex and maternal behavior was associated with children's executive function in a manner consistent with the vulnerability or differential susceptibility model. Participants were 146 36-month-old children and their mothers. Maternal responsiveness and negative reactivity were coded during structured mother-child interactions. Executive function was operationalized as latent self-control and working memory/inhibitory control (WMIC). Structural equation modelling supported a sex by responsiveness interaction for self-control but not WMIC. Consistent with a vulnerability model, less responsiveness was associated with poorer self-control for boys relative to girls. Boys' self-control may be more vulnerable to the negative effect of unresponsive maternal behavior helping explain boys increased risk for externalizing behavior problems.
Keywords: Early childhood; Executive Function; Parenting; Sex differences.