Hallucinogens powerfully affect the brain, distorting the way our five senses work and changing our impressions of time and space. People who use these drugs a lot may have a hard time concentrating, communicating, or telling the difference between reality and illusion.
Your brain controls all of your perceptions -- the way you see, hear, smell, taste, and feel. How does your brain communicate with the rest of your body? Chemical messengers transmit information from nerve cell to nerve cell in the body and the brain. Messages are constantly being sent back and forth with amazing speed.
Your nerve cells are called neurons, and their chemical messengers are called neurotransmitters. When neurotransmitters attach to special places on nerve cells (called receptors), they cause changes in the nerve cells.
This communication system can be disrupted by chemicals like hallucinogens, and the results are changes in the way you sense the world around you.
MDMA and MDA cause neurons to release a neurotransmitter called serotonin. Serotonin is important to many types of nerve cells, including cells that receive sensory information and cells that control sleeping and emotions. The released serotonin can over activate serotonin receptors.
In animals, MDMA and MDA have been shown to damage and destroy nerve fibers of neurons that contain serotonin. This can be a big problem, because serotonin neurons have a role in so many things, such as mood, sleep, and control of heart rate.
Scientists have recently found that the damaged serotonin neurons can regrow their fibers, but the fibers don't grow back normally. The fibers may regrow into brain areas where they don't normally grow, but not into other brain areas where they should be located. The new growth patterns may cause changes in mood, learning, or memory.