In Pharrell Williams popular song “Happy” he sings “Happy/Bring me down/Can’t nothing bring me down/My level’s too high…” Little did Williams know that a recent article in Scientific American would highlight the growing importance of new neurons, or brain cells, appearing in adults’ brains and how a shortage of such cells could contribute to anxiety disorder like PTSD or panic attacks. One area of the brain where new neurons appear is in the hippocampus, which is involved with learning, memory, and emotion. Individuals with anxiety disorders such as PTSD have difficulty distinguishing between terrifying experiences from the past and harmless situations. A boost of new neurons in the hippocampus, accomplished by medication, exercise, and perhaps even psychotherapy, may reduce such symptoms of anxiety. Listen in to a fascinating interview with Dr. Mazen Kheirbek about the prevalence and nature of anxiety disorders and how stress can impede the formation of new neurons: http://www.prx.org/pieces/104157-relaxation-through-neurogenesis-groks-science-s#description .