Do you remember the commercial where the actor fries and egg and says, “This is your brain, on drugs� Do drugs fry your brain, and is a little drug use enough to cause permanent damage?
The subject of drug use and the effects on the brain are always controversial. What constitutes a drug, and can relatively tame drugs, like marijuana, do any damage? If you experimented with drugs in your teens will it come back to bite you later on? Some people go so far as to say that use of drugs like cocaine or ecstasy can actually put holes in your brain.
First, lets dispel the rumor about holes in the brain. The only thing that can put a hole in your brain is brain injury due to physical trauma, or disease. Drugs cannot produce a hole in your brain. That being said, the damage drugs can do are just as bad. 
Your brain stem controls all the functions of your body – breathing, blood circulation, memory, etc. It links the brain to the spinal chord – responsible for muscle and limb movement. Drug abuse affects this and two other primary areas of the brain, the limbic system (controls emotions) and the cerebral cortex (outer part of the brain that processes information), which is the thinking area of the brain. When drugs are introduced they can interrupt the workings of these areas of the brain and even change how the brain performs certain jobs. These changes can lead to addiction.
Drugs tap into the communication center of the brain, interfering with the way the nerve cells normally send, receive and process information. Due to their chemical structure, different drugs react differently, and some can even make permanent changes even if taking the drugs has stopped.
One recent study states that using drugs like marijuana only cause minor memory loss, while another claims that heavy marijuana use can permanently shrink parts of your brain. Drugs such as marijuana and heroin activate neurons because their chemical structures imitate that of our natural neurotransmitters. They trick receptors and can activate nerve cells, although they don’t work the same way as a natural neurotransmitter, and send abnormal messages to the brain.
Amphetamines cause nerve cells to release excess amounts of natural neurotransmitters, or prohibit the normal recycling of brain chemicals (cocaine and amphetamines) that lead to exaggerated messages in the brain. This causes chaos in the communications channels of the brain.
All addictive drugs, including nicotine and marijuana, affect the brain’s “reward†circuits – part of the limbic system, and cause the brain to release extremely large amounts of dopamine that causes you to feel pleasure. This flood of dopamine is what gives you the ‘high’ feeling associated with drug use.
Researchers claim short-term and long-term changes occur in the brain by lowering the impact of chemicals used to communicate brain signals (neurotransmitters) – like dopamine. Eventually, more and more of the drugs are needed in order to get the same feeling. That is what causes the addictions. They also believe that changes in the levels of neurotransmitters can result in problems with neuron function. It is debatable whether these changes will remain permanent.
A study in New Scientist (August 2008) claims the reason addicts have a difficult time staying off drugs is because permanent change has occurred within the brain due to long-term use of some drugs that actually causes certain structures in the brain to grow.
This article was shared by Two-time USA Memory Champion, memory training expert and memory speaker, Ron White.
Sources:
NIDA for Teens: Brain and Addiction: http://teens.drugabuse.gov/facts/facts_brain1.php
Discovery, Fit & Health – You Can Get Holes in Your Brain Through Drug Use: http://health.howstuffworks.com/human-body/systems/nervous-system/10-brain-myths8.htm