Delta-9-tetrahydrocannabinol, the active compound in cannabis, temporarily alters how brain regions communicate with each other. In 19 occasional cannabis users who underwent two resting-state fMRI scans—one shortly after smoking a cannabis cigarette and one after at least a week without cannabis—a transient connectivity state appeared only during intoxication. This state showed high connectivity within and between auditory and somato-motor cortices, along with anti-correlation with subcortical structures and the cerebellum. Subjective perceptual changes and THC plasma levels were linked to this state, suggesting a neural biomarker of cannabis intoxication.
Personality traits, particularly the dimension of self-transcendence measured by Cloninger's Temperament and Character Inventory, correlate with people's intuitive inclinations toward either dualism or reductive materialism regarding the mind-body problem. In a pilot study using a newly developed questionnaire based on analytic philosophy of the mind, participants categorized as dualists showed significant differences in self-transcendence scores compared to those categorized as reductive materialists. The findings suggest that philosophical positions on the mind-body problem, and possibly responses to thought experiments in philosophy of mind, may be influenced by underlying personality features, a factor that should be considered in future philosophical and empirical research.