Human brain development timeline

Studies report that three primary structures are formed in the sixth gestational week.

[6] The appearance of cortical folds first takes place during 24 and 32 weeks of gestation.

[8] Cortical grey matter development peaks at ~12 years of age in the frontal and parietal cortices, and 14–16 years in the temporal lobes (with the superior temporal cortex being last to mature), peaking at about roughly the same age in both sexes according to reliable data.

This may bring into question the effectiveness of brain development studies in treating and successfully rehabilitating criminal youth.

[9] It's a common misconception to believe the brain stops development at any specific age.