The results from the main study replicated in an independent cohort (n = 303). A, ISC decreased with age in the replication cohort. ISC was computed for each individual by correlating responses from individual subjects to those from all other subjects (regardless of age and sex) for that stimulus. Correlation values ranged from r = –0.37 to r = –0.44. Note that for every stimulus, a different number of subjects was available. B, Across all stimuli, ISC was higher for younger subjects (6–14 yr, light green) than it was for older subjects (15–44 yr, dark green) in the replication cohort. For consistency, the split between the ages was consistent between this study and the main study. C, Across all stimuli, ISC was higher for males (blue) than females (red) in the replication cohort. For both B and C, ISC was computed separately within each age and sex group. Black lines indicate the median. D, Sex differences in the young disappeared with age in the replication cohort. Young males were more neurally similar to each other than young females, and this sex difference was absent in the older group. Here, ISC was computed within each sex and age group separately and averaged across all stimuli used in the replication cohort. Black lines indicate the median.