Marijuana use, introspectiveness, and mental health.

Conflicting evidence suggests that marijuana use may be associated with either positive or negative mental health. This study explores the possibility that the association of marijuana use with mental health differs among various subgroups of users. Specifically, we investigate the hypothesis that marijuana use and the personality disposition of introspectiveness interact in their effects on psychological well-being. Results support this hypothesis and show that marijuana use is associated significantly with psychological distress for highly introspective individuals. In contrast, marijuana use has no such association for those low on introspectiveness. Additional evidence shows that marijuana use involves primarily self-oriented cognitive and emotional experiences for highly introspective individuals, whereas for those low on introspectiveness it is characterized more often by perceptual distortions and sensorimotor sensations.