The Road to Recovery: A Neural Characterization of Cocaine Abstinence.

摘要

Cocaine addiction is a significant public health issue with an outsized effect on the individual and society at large. A principal reason for the immense social and personal costs associated with cocaine addiction is the difficulty in remaining abstinent. Utilizing diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI), current cocaine dependence has been associated with deficits in white matter integrity and atypical neural activation in multiple cognitive control regions. However, while the neurobiological and behavioral deficits associated with current cocaine dependence have been well-characterized, it is relatively unknown if these deficits persist after the cessation of cocaine use. To elucidate neurobiological functioning during cocaine abstinence, we conducted three experiments utilizing either DTI or fMRI methodology in cocaine dependent (CD) individuals at varying periods of abstinence. The results of these investigations show that as a group, abstinent CD individuals do not display the same neurobiological deficits as current users. We speculate that the absence of these deficits may be partly due to the intensive drug-treatment programs the participants were enrolled in. However, when we conducted subject-level examinations, we found that abstinent CD individuals displayed neurobiological functioning related to the duration of abstinence. We postulate then that continued abstinence may be responsible for an amelioration of neurobiological deficits or reflect preexisting differences that allow for extended abstinence. Additionally, we observed participant-level differences that were not a function of duration of abstinence leading us to speculate that recovery occurs at temporally different rates in some individuals. Overall, it appears that while a majority of recovering individuals do not display the neurobiological deficits associated with current cocaine users, there exists a subset of individuals that continue to display these deficits. We hypothesize that those individuals who continue to display neurobiological deficits will have the greatest risk of cocaine relapse.