Faster Grooved Pegboard Test scores, measured as total time in seconds to complete the test, correlated with greater normalized myelin content. The correlation was significant (Table 3) for the left hemisphere when the test was executed with the dominant hand (P = 0.009) and for both hemispheres with respect to the non-dominant hand (P = 0.013 for the left and P = 0.011 for the right hemispheres). For area 23c and p24', faster time to pegboard completion time correlated with lower normalized myelin content (see also Figure 6). For area 23c, faster pegboard test scores of the non-dominant hand correlated with lower normalized myelin content (P = 0.011 for the left; P = 0.027 for the right hemisphere). For area p24', significant correlations were restricted to the right hemisphere for both dominant (P = 0.013) and non-dominant (P = 0.001) hands. In general, faster performance and greater myelin content were associated with older age of the adolescents.
