 - Purpose : Deficits in executive functioning may explain why many individuals with addiction are unable to avoid high-risk contexts or manage the experience of craving that lead to substance use. The principal objective of this project is to acquire resting state functional Magnetic Resonance Imaging fMRI and diffusion tensor imaging DTI data on patients with current addiction who will then complete through a distinct protocol mobile assessments of daily life executive fluctuations, craving, and substance use. 