Resurgence of Cocaine-Seeking in Rats Following Long Access and Punishment

Strategies that provide access to alternative non-drug rewards are among the most effective at reducing substance use in individuals with substance use disorders, but relapse often occurs when alternative rewards are removed. Relapse induced by the loss of alternative rewards is called resurgence, and represents a challenge to otherwise effective strategies for reducing drug use. An animal model has been useful for studying resurgence, but the extant model has two limitations. First, humans usually refer to the negative consequences of drug use as the reason they stop taking drugs, but the extant model uses drug unavailability to reduce drug seeking. Second, individuals with substance use disorders display behaviors that can be summarized as uncontrolled drug seeking, but the extant model does not simulate uncontrolled drug seeking. Chapter 2 addressed the first concern by studying resurgence of previously-punished cocaine seeking. Chapter 3 addressed the second concern by using procedures shown to simulate uncontrolled drug seeking in rats to study resurgence of previously-punished cocaine seeking. Chapter 2 showed that resurgence of cocaine seeking can occur following suppression by punishment, and Chapter 3 showed that resurgence may be unaffected following procedures shown to increase relapse in other models. The models developed herein should contribute to future research into resurgence by better simulating the conditions under which individuals with substance use disorders experience relapse