Marijuana has a chemical compound called tetrahydrocannabinol, also known as THC. Tetrahydrocannabinol mimics substances called endocannabinoids that human bodies produce. In the brain endocannabinoids control the production of neurotransmitters. Throughout the rest of the body endocannabinoids work by relaxing muscles, reducing inflammation, protecting damaged tissue, and regulating appetite and metabolism. Because endocannabinoids are so crucial to the human body, the brain has receptors ready for them. When consumed, the marijuana triggers the endocannabinoids into producing more than needed, leading to memory issues, augmented levels of pain, and alterations to emotion, pleasure, and movement control. Substantial evidence from animal research and a growing number of studies in humans are leading to a conclusion that the exposure to marijuana during development can cause permanent changes in the brain. Rats exposed to tetrahydrocannabinol during adolescence show evident problems with specific learning and memory tasks later in life. When two adult rats were put together in a cage the one who consumed tetrahydrocannabinol as an adolescent was less hesitant to try another type of drug were when given the opportunity. As for humans, their brains are usually not fully developed until the age of 25. When a teenager is exposed to drugs such as marijuana it interferes with the developing connections between brain regions and producing cells that process information. Research>