The who and how of attentional bias in cannabis users: associations with use severity, craving and interference control

Aims Cognitive and motivational processes are thought to underlie cannabis use disorder (CUD), but research assessing how cognitive processes [e.g. interference control (IC)] interact with implicit [e.g. attentional bias (AB)] and explicit motivation (i.e. craving) is lacking. We assessed the presence of AB in cannabis users with varying use severity and tested models of moderation, mediation and moderated mediation to assess how AB, craving and IC interact in their association with measures of cannabis use. Design A cross-sectional study design was used. Setting and participants Eight studies performed by our laboratory in the Netherlands including never-sporadic, occasional (<= 1/month) and regular cannabis users (>= 2/week), and individuals in treatment for CUD were combined (n = 560; 71% male). Measurements Studies included a classic Stroop task (IC), a cannabis Stroop task (AB) and measures of session-induced and average session craving. Both heaviness of cannabis use (grams/week) and severity of use related problems were included. Findings Only those in treatment for CUD showed an AB to cannabis (P = 0.019) and group differences were only observed when comparing CUD with never-sporadic users (P = 0.007). In occasional and regular users, IC was negatively associated with heaviness (beta = 0.015, P < 0.001), but not severity of use. Average session craving (exploratory), but not session-induced craving (confirmatory), mediated this association between AB and heaviness (beta = 0.050, P = 0.011) as well as severity of use (beta = 0.083, P = 0.009); higher AB was associated with heavier use and more severe problems through increased craving. Conclusions Attentional bias only appears to be present in cannabis users with the most severe problems and craving appears to mediate the association between attentional bias and both heaviness and severity of use in occasional and regular users. The association of interference control with heaviness but not severity of use may point to subacute intoxication effects of cannabis use on interference control.