In schizophrenia, an array of gene variants constitute a risk for the disease, and certain times of major stress early in life regulate those genes in such a way that things divert onto the road leading to schizophrenia. These manifestations then include an excess of dopamine and sparse neuron- to-neuron connections in the frontal cortex. Why the late-adolescent/ early-adult onset typical of the disease? Because that’s when the frontal cortex is having its final burst of maturational growth
