Psychological correlates of risky cannabis use: Alexithymia, frontal lobe dysfunction and impulsivity

A community sample of young adult cannabis users was recruited. Of the 138 participants, 71.7% were defined by their Cannabis Use Disorder Identification Test (CUDIT) scores as low risk cannabis users, whereas 28.3% were risky cannabis users. The CUDIT risk group was significantly associated with the Toronto Alexithymia Scale (TAS-20) defined alexithymia group, p = .004. CUDIT scores were significantly positively correlated with all three TAS-20 alexithymia subscale scores, Barratt Impulsiveness Scale (BIS-11) impulsivity, and all three frontal lobe dysfunction subscales of the Frontal Systems Behavior Scale (FrSBe). A two-way (CUDIT risk group X gender) between-subjects multivariate analysis of covariance (MAN-COVA) was performed on scores obtained from the TAS-20 subscales, FrSBe subscales, and BIS-11; using age as the covariate. The multivariate effect of the CUDIT group was significant, p < .0001. Univariate effects of the CUDIT group were significant for all measures. Heavy cannabis use is known to be associated with residual effects including deficits in frontal lobe functioning that may persist for up to five weeks of abstinence; thus, it is tempting to regard these correlates of risky cannabis use as reflecting residual effects. However, traits such as alexithymia, poor impulse control and executive dysfunction have all been linked to the predisposition to abuse drugs and alcohol. Both directions of causation may apply, for example, those with inherently lower emotion regulation and executive self-control abilities may be more likely to abuse substances, and substance abuse itself may further impair executive functioning and self-regulation.