What weed does to your brain, per hundreds of thousands of scans

Key Points:

• Habitual marijuana use can negatively impact the body, including lung irritation, blood vessel damage, increased heart rate, and severe symptoms like vomiting associated with heavy long-term use.
• Brain imaging studies reveal that marijuana use leads to reduced cerebral blood flow, particularly affecting regions responsible for memory, coordination, emotion, and executive function, largely due to THC's impact.
• THC disrupts motor control by affecting the cerebellum and basal ganglia, impairs memory formation by reducing hippocampal blood flow, and diminishes judgment and impulse control by lowering prefrontal cortex activity.
• Marijuana use can cause difficulties with attention, planning, and multitasking, alter sensory perception by intensifying or dulling senses, and increase risks of anxiety, paranoia, psychosis, and mood disorders, especially in frequent users or those genetically predisposed.
• While some brain changes may improve after quitting, research indicates marijuana generally leads to global reductions in brain function rather than enhancements, with chronic use linked to lasting cognitive and emotional impairments.