 The field of neuroscience is growing rapidly. Continuous advancements in imaging and experimental methods are helping to deepen our understanding of how the central nervous system works at the molecular, cellular, circuit, and system levels. To share the latest developments made across the vast field of neuroscience, Labroots is hosting its fourth annual free online conference, Neuroscience 2016. The conference features talks given by leading experts in neural circuitry, neurodegenerative disorders, psychiatric disease, and neuron biology. Contrary to the dogma of past decades, researchers have found that new neurons form and mature in specific areas of the brain well into adulthood. Recent studies led by Dr. Fred Gage, Professor in the Laboratory of Genetics at the Salk Institute for Biological Studies, have revealed that certain environmental stimuli and specific molecules in the brain can regulate how newborn neurons proliferate, migrate, and differentiate. In his keynote address, Dr. Gage discusses novel methods for monitoring the maturation of neurons in vivo, as well as the role that new neuron formation might play in the adult brain. Among the various factors that control how the central nervous system operates, the bacteria that reside in the gut are probably not the first that come to mind. But in fact, this microbiota plays a major role in the development of bodily systems that can affect the central nervous system. And the brain, in turn, can induce changes in the composition of the bacterial community. Research on mice conducted by Dr. John Kryan, Professor and Chair of the Department of Anatomy and Neuroscience at University College Cork, explores how this two-way microbiota gut-brain axis works. Dr. Kryan discusses how altering the gut microbiota during early life and taking probiotics during adulthood produce neurochemical, molecular, and behavioral effects. The results suggest that dietary approaches could help treat stress-related neurodevelopmental disorders and even neurodegenerative disease. In a world full of options and opportunities, our brains must evaluate and select actions to seek specific rewards at the expense of others. Dr. Stan Floresco, Professor in the Department of Psychology at the University of British Columbia, describes how different dopamine-carrying circuits influence our judgments about varying and uncertain risks and rewards. These findings reveal how competing cortical and subcortical circuits shape our selection of certain actions and our processing of rewarding outcomes. In some instances, however, this neural circuitry can be seriously impaired, leading to disastrous personal consequences. Such is the case with drug addiction. To better understand how drug addiction affects the brain, Dr. Rita Goldstein, Professor in the Department of Psychiatry and Neuroscience at the Icon School of Medicine at Mount Sinai, uses a suite of imaging tools to observe how the drug-addicted brain behaves. This approach is revealing the neurobiological mechanisms underlying how drug addiction compromises brain function and alters brain structures related to dopamine signaling. In addition, Dr. Goldstein discusses the effects of abstinence and other interventions in reversing the neural dysfunction caused by cocaine addiction in humans. At Neuroscience 2016, these speakers join a cast of other research scientists, principal investigators, lab directors, clinicians and medical professionals from around the world to advance our knowledge of the brain and nervous system.