Understanding the neural and environmental mechanisms of reward-related learning is central to understanding behavior in general and crucial to understanding psychopathologies like addiction, pathological impulsivity and depression. Thus, my research is aimed at delineating the environmental and neural mechanisms underlying reward-related learning, motivation and drug addiction. In my laboratory, we focus on (1) the neural and environmental mechanisms whereby goal-directed behavior is acquired and expressed and (2) the neural and environmental mechanisms underlying the acquisition, maintenance and reinstatement of drug-taking and drug-seeking. Several neural pathways have been implicated in reward-related learning and we currently are engaged in developing neural models that help us understand the neural plasticity occurring in specific regions of these pathways as a function of reward-related learning. Currently, the behavioral paradigms that we use include operant and classical conditioning (e.g., self-administration of drug or food) and the neuroscience techniques include psychopharmacology, neuropsychopharmacology and immunohistochemistry.