Even though cognitive deficit is often linked with cannabis abuse in a healthy population, a recent study showed the opposite in first-episode schizophrenia (FES) patients. Thirty FES patients who had been lifetime cannabis users showed less impaired cognitive functioning with the most prominent difference in visual memory compared to fifty-five FES non-users. A comparison of the healthy controls who used cannabis, and those who did not, revealed no sizeable differences in cognitive performance between the groups.
Reference:
Hájková, M. et al. Cognitive performance and lifetime cannabis use in patients with first-episode schizophrenia spectrum disorder. Cogn Neuropsychiatry 26, 257–272 (2021).
