Courtesy National Institute on Drug Abuse
Your brain is who you are. It’s what allows you to think, breathe, move, speak, and feel. It’s just 3 pounds of gray-and-white matter that rests in your skull, and it is your own personal “mission control.” Information from your environment—both outside (like what your eyes see and skin feels) and inside (like your heart rate and body temperature)—makes its way to the brain, which receives, processes, and integrates it so that you can survive and function under all sorts of changing circumstances and learn from experience. The brain is always working, even when you are sleeping. Learn more about the brain-body connection.
The brain is made up of many parts that all work together as a team. Each of these different parts has a specific and important job to do.
When drugs enter the brain, they interfere with its normal processing and can eventually lead to changes in how well it works. Over time, drug use can lead to addiction, a devastating brain disease in which people can’t stop using drugs even when they really want to and even after it causes terrible consequences to their health and other parts of their lives.