Genuine revolutions in science are rare. The acceptance of adult neurogenesis is one of these, recognition that the central nervous system of mammals contains neural stem cells capable of replicating normal cell types, including neurons. Samuel Weiss, PhD, demonstrated this in experiments with mice in 1992. His discovery of the metabotropic glutamate receptor remains a defining moment in establishing neurogenesis research as a pathway to exploring treatments for Parkinson’s, Alzheimer’s, stroke, ALS, and multiple sclerosis through neurological repair. Since then, Dr.