The effects of marijuana consumption, which can cause the lungs, damage blood vessels, and accelerate heart rate, can also cause long-term, heavy use. According to Dr. Daniel Amen, founder of Amen Clinics, who has conducted hundreds of thousands of scans to measure blood flow and activity in patient brains, indicates measurable changes in brain function. The legalization of cannabis in many states has increased access to the drug, putting the brain in the crosshairs. The main psychoactive compound of marijuana, THC, disrupts the brain’s cerebellum and basal ganglia, responsible for motor control, balance and coordination. THC also binds to receptors in the hippocampus, which plays a critical role in memory formation. These effects can be seen in the first hour after marijuana use and last several hours.