Drug addiction is a chronically relapsing disorder characterized by compulsion to use one or more drugs of abuse coupled with inability to control drug intake. Drug craving and relapse are precipitated by re-exposure to a previously abused drug, an environment associated with prior drug use or a stressful life event. Over 80% of smokers in the U.S. want to quit, fewer than 5% succeed, indicating a high relapse for this drug. My current research addresses basic questions regarding the cellular, molecular and behavioral neurobiological changes induced by nicotine consumption, specifically during nicotine withdrawal and relapse. My specific project involves understand how nicotine-induced activation of nicotinic receptors could be linked to subunit composition and/or transmembrane protein-complex-mediated synaptic plasticity during nicotine withdrawal and relapse.