No differences in neural responses or performance during cannabis cue-specific inhibitory control tasks between recreational cannabis users and non-users: Insights from fNIRS.

Background: Impaired inhibitory control has been observed in regular cannabis users. Theories suggest that regular cannabis use is maintained by reward-driven behaviour, which may be underpinned by adaptations in neural reward and inhibitory control systems, thus increasing vulnerability to dependency.

Aims: This study investigated neural correlates of cannabis cue-specific inhibitory control in regular cannabis users and non-users using functional near-infrared spectroscopy (fNIRS).

Methods: Thirty regular cannabis users and thirty non-user controls completed two inhibitory control tasks (Go/No/Go and Stop-Signal Task), and a measure of attentional bias (Cannabis Stroop task). fNIRS recorded prefrontal and orbitofrontal haemodynamic responses (oxygenated haemoglobin and deoxygenated haemoglobin). Group comparisons and exploratory regressions examined cannabis use characteristics as predictors of behavioural and neural outcomes.

Results: No significant group differences were found in behavioural performance or haemodynamic activity across tasks. Exploratory regressions showed no significant associations between cannabis use characteristics and behavioural or neural outcomes after adjusting for covariates.

Conclusions: No evidence of impaired inhibitory control, attentional bias, or differences in prefrontal function were found in non-dependent cannabis users. Future studies should investigate whether such deficits emerge with heavier or dependent use.