Contingency Management for Meth in South Africa Methamphetamine Abuse in South Africa

This study will correlate MA-abstinence outcomes from an 8-week program of voucher-based incentives using an escalating schedule for 30 treatment-seeking, MA-dependent individuals with scores on tasks of working memory and assessments of neuropsychological and demographic status. At the beginning and end of the CM program, participants will participate in MRI scans while performing a working memory task and will complete a battery of select neurocognitive and psychological assays to address two specific aims: (1) to determine whether changes in neural function within frontostriatal circuitry from baseline to end of the 8-week CM program are associated with parallel changes in measures of cognitive control and impulsivity and with MA abstinence outcomes and (2) to determine whether structural changes in frontostriatal circuitry over the 8-week CM intervention correspond with neurocognitive, psychological and MA abstinence measures.

Inclusion criteria

• provide voluntary informed consent
• meet DSM-5 criteria for MA or amphetamine use disorder
• provide at least one urine sample positive for MA/amphetamine metabolites during screening (i.e. prior to the commencement of the study).
• aged 18-45
• right-handed
• English-speaking

Exclusion criteria

• currently receiving treatment for stimulant addiction or needing more intensive treatment than outpatient care
• meet DSM-5 criteria for substance use disorder other than nicotine
• unable to attend 4+ visits during the 2-week screening period or to complete measures
• Physical or mental illness that would require intervention that would alter imaging or that would interfere with safe study participation
• pregnant, claustrophobic, or have metal prostheses, cardiac pacemakers, or metal clips that are incompatible with the scanner
• HIV positive status
• unable to comprehend written or spoken English
• currently taking psychiatric medication