How does social isolation reshape the brain and behavior? Scientists have shown that extended deprivation of social contact affects human health and well-being. Social isolation is linked to increasing rates of anxiety, depression, violence, cognitive decline, heart disease and more, and yet we know relatively little about how the brain encodes this state. Taking a deep behavior approach, Moriel Zelikowsky and her group are exploring how cellular communication via long-acting, long-range neuromodulatory transmission may unlock the mystery of how the brain encodes social states such as those produced by prolonged social isolation.