Fig. 1.

Cortical maturation and behavioral patterns in developmental trajectory of major mental illnesses. The upper panel shows the developmental trajectory of brain maturation. Brain maturation, including maturation of interneurons and dopaminergic projections, pruning of glutamatergic synapses, and increased myelination, occurs from birth to young adulthood, most dynamically during adolescence. Stress mediators regulated by genetic and environmental factors affect this maturation processes during this critical period. Aberrant brain maturation induced by stress mediators might be an essential mechanism underlying the disease. The lower panel shows the course of abnormal behavioral patterns related to major mental illnesses. Disturbance of brain maturation caused by stress mediators during the critical period may increase vulnerability to major mental illnesses, for which the devastating behavioral phenotype (over the threshold) will begin to emerge in late adolescence and early adulthood. Adapted from Jaaro-Peled and colleagues, with permission from Elsevier.³⁰