A recent study published in the research journal Neuropsychopharmacology suggests that neurobiological changes produced by exposure to nicotine in adolescence can lead to adult depression. While correlational evidence has already demonstrated the relation between tobacco consumption and mood disorders, this study is unique in that it is one of the first to demonstrate how tobacco consumption during the developmental years can have long-term neurobiological consequences. In the study, adolescent rats were either injected with nicotine or saline based solutions for 15 days. Depression-like symptoms were noticed in the adult rats injected with the nicotine solution. The now adult rats had lower sensitivity to sucrose rewards and were higher sensitivity to anxiety-inducing situations.