Inhibitory control in young adolescents: the role of sex, intelligence, and temperament

OBJECTIVE: Inhibitory control is associated with temperament and intelligence, which together form an essential component of the ability to adaptively regulate behavior. Impairments in inhibitory control have been linked with a host of common and debilitating conditions, often in a sex-dependent manner. However, sex differences in inhibitory control are often not expressed experimentally during task performance. Here, we sought to examine how sex, temperament, and intelligence are related to different aspects of inhibitory control. METHOD: We recruited a large sample of early adolescents (n = 153; mean age 12.6 years) to comprehensively investigate the relationship between sex, self-reported and parent-reported temperamental effortful control, and intelligence with different aspects of inhibitory control--namely, strategic (or proactive) control and evaluative (or reactive) control, assessed using a modified Stroop task. RESULTS: Compared with males, females were more efficient in their use of strategic control to reduce the magnitude of response conflict. There was no sex difference in evaluative control. Further, whereas high intelligence was associated with fewer errors for both males and females, effortful control was associated with performance accuracy only in females. CONCLUSIONS: These findings highlight sex differences in the relationship of inhibitory control to individual differences in temperamental effortful control in early adolescents and reinforce the generalized positive effects of intelligence.