WHY IT MATTERS: Parents and young patients who view occasional THC use as low-stakes should understand that the adolescent brain processes cannabinoids differently than an adult brain, and even limited exposure during developmental years can have measurable effects on mood regulation, memory, and long-term mental health trajectory. CLINICAL OVERVIEW: Cannabis use during adolescence and young adulthood intersects with critical windows of neurodevelopmental maturation, particularly in the prefrontal cortex and limbic system, where endocannabinoid signaling plays a foundational regulatory role. Even casual or infrequent THC exposure during these years carries a distinct risk profile compared to adult use, including associations with altered executive function, increased vulnerability to anxiety and mood disorders, and in genetically susceptible individuals, elevated risk for psychosis-spectrum conditions.