Adolescent neurodevelopmental trajectories show a dynamic, complex, and predictable change, with regionally different rises and falls in volume or cortical thickness notable in the age range between 7 and 18 years but with most changes occurring between 9 and 13 years. These neurodevelopmental trajectories were established from data typically collected at 2-year intervals (Lenroot and Giedd, 2010; Shaw et al., 2008), although the NIH-PD study adjusts its interval by age, where infants and children age 7 days to 4 years are scanned up to 5 times at 3 or more month intervals, whereas children to adolescents age 5–18 years are scanned 3 times in 2-year intervals (Evans, 2006). In the NIH-CHPB longitudinal study, Lenroot et al. (Lenroot et al., 2007) reported on 387 boys and girls and men and women, age 3 to 27 years, and showed that total cortical gray matter volume peaked at 10.5 years in girls and 14.5 years in boys. Cortical frontal gray matter volume of girls peaks about a year before that of boys (10.5 compared with 11.5 years of age). This sex-related difference in
