Value-based decision-making and behavioral economic constructs that distinguish people with and without cannabis use...

Behavioral economic accounts posit that distorted valuation processes underlie cannabis decisions; however, less is known about the moment-to-moment dynamics through which value influences observable choice behavior. This study explored whether value-based decision-making and behavioral economic constructs distinguish people with and without cannabis use history. Sixty participants were recruited, half with a history of cannabis use (cannabis group) and half without (control group). Participants completed a value-based decision-making task (choosing between previously rated cannabis-related and cannabis-unrelated images). A drift-diffusion model was fitted to behavioral data (choice and response time patterns) to estimate reinforcer-specific parameters, including evidence accumulation rates and response thresholds. Compared with controls, participants with history of cannabis use had higher cannabis evidence accumulation rates (p = .023). Exploratory analyses revealed higher self-report cannabis demand across most indices (all except P_max; ps ≤ .042). However, groups did not differ in cannabis-unrelated evidence accumulation rates or response thresholds for either decision type (ps ≥ .186). Notably, controls showed higher cannabis-unrelated than cannabis evidence accumulation rates (p = .001). People with a history of cannabis use ascribe a higher value to cannabis than those without such history, who in turn value cannabis less than alternative reinforcers-a pattern consistent with behavioral economic accounts of addiction.