A critical period for frontal cortex plasticity has not been defined, but behavioral studies show that performance on tasks including inhibitory control, decision making and processing speed continue to develop during adolescence. During adolescence tasks of selective attention, working memory and problem solving improve, consistent with frontal cortical synaptic pruning and myelination improving performance (Blakemore and Choudhury, 2006). Inhibitory control involves executive functions that improve from adolescence to adulthood. Studies measuring behavioral inhibition on a Go-NoGo task and fMRI data reveal greater activation of DLPFC and OFC in children than in adolescents, and greater in adolescents than in adults, with the adults showing the lowest dorsolateral, but equal orbitofrontal activation and greater inhibitory control performance (Casey et al., 1997; Tamm et al., 2002). These studies support the concept that the immature brain has more extensive and less efficient frontal activation and lower performance compared to adults, who have a more focused pattern of frontal activation, faster reaction times, and better performance (Blakemore and Choudhury, 2006). Taken together these studies suggest that remodeling of the cortex during the transitions from youth to adolescence to adulthood have functional implications for the entire adult life.
