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AimsTo understand processes placing individuals at risk for stimulant (amphetamine and cocaine) use disorder.DesignLongitudinal study.SettingUniversity of California, San Diego Department of Psychiatry, CA, USA.ParticipantsOccasional stimulant users (OSU; n=184) underwent a baseline clinical interview and a functional magnetic resonance imaging (fMRI) session. On the basis of a follow-up clinical interview completed 3 years later, OSU (n=147) were then categorized as problem stimulant users (PSU: n=36; those who developed stimulant use disorders in the interim) or desisted stimulant users (DSU: n=74; those who stopped using). OSU who did not meet criteria for PSU or DSU (n=37) were included in dimensional analyses.MeasurementsfMRI blood oxygen level-dependent (BOLD) contrast percentage signal change from baseline collected during a Paper-Scissors-Rock task was examined during three decision-making conditions, those resulting in: (1) wins, (2) ties and (3) losses. These data were used as dependent variables in categorical analyses comparing PSU and DSU, as well as dimensional analyses including interim drug use as predictors, controlling for baseline drug use.FindingsPSU exhibited lower anterior cingulate, middle insula, superior temporal, inferior parietal, precuneus and cerebellum activation than DSU across all three conditions (significant brain clusters required >19 neighboring voxels to exceed F(1,108) =5.58, P0.83). Higher interim marijuana use was linked to lower pre-central and superior temporal activation during choices resulting in wins (>19 neighboring voxels to exceed t=2.61, P0.11).ConclusionsIndividuals who transition from stimulant use to stimulant use disorder appear to show alterations in neural processing of stimulus valuation and outcome monitoring, patterns also evident in chronic stimulant use disorder. Attenuated anterior cingulate and insular processing may constitute a high-risk neural processing profile, which could be used to calculate risk scores for individuals experimenting with stimulants.

© 2015 Society for the Study of Addiction. Aims: Adolescents with substance use disorders (SUD) exhibit hyposensitivity to pleasant internally generated (interoceptive) stimuli and hypersensitivity to external rewarding stimuli. It is unclear whether similar patterns exist for aversive interoceptive stimuli. We compared activation in the insular cortex and other brain regions during the anticipation and experience of aversive stimuli between adolescents with SUD and those without. Design: Cross-sectional experimental study with two groups. Participants: Adolescents (ages 15-17years) with an alcohol or marijuana SUD (n=18) and healthy comparison subjects (CON, n=15).Participants were recruited by distributing flyers at local high schools. Setting: Keck Imaging Center, University of California San Diego, CA, USA. Measurements: Behavioral and neural responses to a continuous performance task with inspiratory breathing load recorded during an fMRI session. Questionnaires assessed life-time drug use, anxiety, sensation-seeking, impulsivity, affect and bodily awareness. Visual analog scales assessed drug craving and breathing load responses. Findings: Across subjects, experience of breathing load elicited greater bilateral anterior and posterior insula (AI and PI, respectively) activation than anticipation (F(1,31)=4.16, P