This project aims to collect a densely sampled neuroimaging dataset among individuals receiving medications for opioid use disorder (MOUD). MOUD is multiphasic, comprised of medication induction, stabilization, ongoing treatment, and eventual dis-continuation phases. However, with a few small exceptions, existing neuroimaging efforts are almost exclusively single time-point assessments which, by definition, fail to capture these clinically relevant transitions and thus also do not capture individual risk and resilience trajectories. The investigators innovation, the characterization of neurocomputational trajectories during clinically relevant phases of MOUD treatment, will provide unprecedented mechanistic insight into the neurobiological basis of recovery. Once characterized, such trajectories may be used in the identification of specific therapeutic windows for additional intervention (e.g., times of increased neural plasticity) and in the design of novel tailored interventions based on known brain mechanisms (e.g., behavioral therapy, neurostimulation, neurofeedback).

MOUD individuals between the ages of 18 and 50 who recently enrolled in methadone treatment at APT Foundation clinics in the greater New Haven area. Investigators will aim to recruit individuals as early as possible in treatment, but individuals may be within the first 6 months of treatment at the time of screening, as this may be necessary to ensure that they are on a stable dose of methadone.

AIM 1 - Longitudinal neural fingerprinting of MOUD to repeatedly characterize neural trajectories of individuals in early methadone treatment.

AIM 2 - Complementary, longitudinal computational phenotyping of MOUD to repeatedly characterize behavioral, computational trajectories of individuals in early methadone treatment.

After participation in the main study, participants will be asked to complete a 15-minute follow up every month for an additional three months.

Inclusion Criteria:

• within the first 6 months of methadone treatment for OUD and on a stable dose of methadone
• eligibility for MRI scanning
• willing to commit to longitudinal study visits

Exclusion Criteria:

• current psychosis, mania, or suicidal ideation with intent, as assessed during screening with the SCID-5
• current co-occurring severe substance-use disorders (excluding nicotine and opioids), as assessed during screening with the SCID-5
• current intoxication or acute withdrawal at time of study visit sufficient to prevent participation based on: behavioral observation, breathalyzer, and SOWS assessment (these individuals will be allowed to enroll at a later date once stable)
• severe cognitive impairment (determined through consent process conducted by trained clinical research staff and during consent quiz or as indicated by a PROMIS Cognitive Function t-score <30 (i.e., score indicating severe impairment)
• Past or present history of intellectual disability or developmental disorder
• Neurological disease (including seizures or epilepsy) as assessed by self-report and by consulting clinic records
• Head trauma with loss of consciousness of more than 30 minutes
• Organ dysfunction or any unstable or untreated medical conditions that may alter cerebral function or interfere with study participation

This study will submit and share data with OpenNeuro. This will include de-identified demographic data, neuropsychological assessment data, clinical assessment data, and fMRI data (raw).

All data will be deposited to OpenNeuro starting 24 months after data collection begins and will be deposited every six months thereafter. OpenNeuro policy states that any data uploaded to their repository becomes publicly available under a Creative Commons CC0 license after a 36-month period beginning from first successful version of the dataset.

OpenNeuro policy states that any data uploaded to their repository becomes publicly available under a Creative Commons (CC) license after a 36-month period beginning from first successful version of the dataset. Users create an account with OpenNeuro account in order to download BIDS formatted files and any associated metadata.