People who stopped using cannabis after experiencing cannabis-induced psychosis and received four months of treatment showed no difference in dopamine D2 receptor availability in the caudate region of the striatum compared to former MDMA users and healthy controls. This suggests minimal lasting effects of cannabis-induced psychosis on dopamine reward mechanisms. A possible reduction in D2 receptor availability in the right putamen was observed, which may reflect a residual effect of antipsychotic medication rather than the psychosis itself.
Repeated use of cannabis and synthetic cannabinoids is associated with short- and long-term adverse effects, with synthetic cannabinoids causing more severe and long-lasting impairments. A literature review of 37 preclinical and 44 human studies found that both acute and repeated consumption of synthetic cannabinoids are linked to executive-function impairment, including deficits in attention, short-term memory, working memory, and cognitive flexibility. The severity of these deficits varies by drug type, dose, quantity, age of onset, and duration of use. Understanding these impairments is important given the rising use of synthetic cannabinoids.