Experimental and observational evidence on substance use and metacognition among adults: a systematic review.
Addictive behaviors August 1, 2026 Sarret Seng, Chizimuzo T C Okoli, Lovoria B Williams et al.
A systematic review of 36 studies (N = 2,852 participants) finds that substance use is generally associated with poorer metacognitive functioning, though effects vary by substance and study design. Experimental evidence shows alcohol's effects are mixed; cannabinoids generally impair metacognitive accuracy and calibration; benzodiazepines impair awareness of performance and error detection; methamphetamine has dose-dependent effects on agency judgments; and nicotine replacement does not restore accuracy after abstinence. Craving states are linked to poorer monitoring and calibration. Observational studies report that cocaine, nicotine, opioid, cannabis, alcohol, and polysubstance use are associated with greater maladaptive metacognitive beliefs and reduced monitoring accuracy, though some clinical comparisons show domain-specific or relatively preserved functioning.