WHY IT MATTERS: Patients who use cannabis regularly, particularly younger adults, should know that emerging longitudinal research is examining how THC may influence the brain’s reward system over time, which could inform how clinicians think about dosing frequency and product selection. CLINICAL OVERVIEW: The endocannabinoid system plays a central role in shaping brain reward circuitry, and THC directly engages this system during periods when neural architecture is still actively developing. Research examining cannabis use and reward anticipation over a 12-month period reflects growing scientific interest in how repeated THC exposure may alter dopaminergic signaling and motivational processing.