Adolescence is a distinct and unique phase of life characterized by rapid physical, neurological, psychological and sexual/hormonal development. Frontal lobe maturation consisting of explosive dendritic/synaptic growth and pruning modulates affect emerging from the amygdala, a process called frontalization. Greater powers of abstraction propel adolescents into new perspectives on their world requiring each adolescent to meet several new intertwined psychological challenges, including formation of values and a separate identify beyond simpler childhood notions, becoming autonomous in thought and feeling, choosing a peer group and finding transcendence and meaning in their life. Marijuana not only interferes with the neurodevelopment necessary to meet these psychological developmental tasks, but it also confuses adolescents by seeming to accelerate maturation while actually delaying it. Declaring autonomy and separation by smoking a joint, for example, produces a simulacrum of maturity without requiring the underlying psychological work that is ultimately necessary for launching into successfull adulthood.