Behind a mystery lies a truth. Just do it.

drawing by marguerita
A brain-imaging experiment I conducted in 2006 explains why antismoking scare tactics have been so futile. I examined people’s brain activity as they reacted to cigarette warning labels by using functional magnetic resonance imaging, a scanning technique that can show how much oxygen and glucose a particular area of the brain uses while it works, allowing us to observe which specific regions are active at any given time
.We found that the warnings prompted no blood flow to the amygdala, the part of the brain that registers alarm, or to the part of the cortex that would be involved in any effort to register disapproval.
To the contrary, the warning labels backfired: they stimulated the nucleus accumbens, sometimes called the “craving spot,” which lights up on f.M.R.I. whenever a person craves something, whether it’s alcohol, drugs, tobacco or gambling.
Op-Ed Contributor - Inhaling Fear - NYTimes.com

Brain Pollution and the Real Reason You Shouldn't Use Drugs

Studying the effects of drugs and alcohol on the brain has clearly been one of the most informative and fascinating parts of my work. I had a sense growing up that drugs and alcohol weren't helpful to my overall health. I might add, this notion was helped along by getting drunk on a six pack of Michelob and half a bottle of champagne when I was sixteen years old - I was sick for three days. After that, I've been lucky enough to stay away from drugs and alcohol. After doing this work there's no way you could get me to do marijuana, heroin, cocaine, methamphetamine, LSD, PCP, inhalants or any more than a glass or two of wine or beer. These substances damage the patterns in your brain, and without your brain you are not you.

There is really quite a bit of scientific literature on the physiological effects of drug abuse and alcohol on the brain. SPECT Scans have demonstrated a number of abnormalities in substance abusers in brain areas known to be involved in behavior, such as the frontal and temporal lobes. There are some SPECT similarities and differences between the damage we see caused by the different substances of abuse. I'll discuss the differences in drug abuse patterns below. There tends to be several similarities seen among classes of abused drugs. The most common similarity among drug and alcohol abusers is that the brain has an overall toxic look to it. In general, the SPECT Scan studies look less active, more shriveled, and overall less healthy. A "scalloping effect" is common amongst drug abusing brains. Normal brain patterns show smooth activity across the cortical surface. Scalloping is a wavy, rough sea-like look on the brain's surface. I also see this pattern in patients who have been exposed to toxic fumes or oxygen deprivation. My research assistant says that the drug brains she has seen look like someone poured acid on the brain. Not a pretty site.

SPECT can be helpful in evaluating the effects of drugs and alcohol on the brain. On 3D surface brain images, several substances of abuse appear to show consistent patterns. For example, cocaine and methamphetamine abuse appear as multiple small holes across the cortical surface; heroin abuse appears as marked decreased activity across the whole cortical surface; heavy marijuana abuse shows decreased activity in the temporal lobes bilaterally and heavy alcohol abuse shows marked decreased activity throughout the brain. These findings tend to improve with abstinence, although long term use has been associated with continued SPECT deficits seen years after abstinence. SPECT can be helpful in several ways in drug and alcohol abuse. First, 3D surface SPECT brain images of drug and alcohol abusers can be used in drug prevention education. Second, SPECT studies can help break though the denial that often accompanies substance abuse. When one is faced with their own abnormal cerebral perfusion it is hard to remain in denial. Third, SPECT may help evaluate if there is an underlying neuropsychiatric condition that needs treatment.

In our experience, the effects of smoking marijuana use typically cause decreased activity in the posterior temporal lobes bilaterally. The damage can be mild or severe, depending on how long a person used, how much use occurred, what other substances were used (nicotine is a powerful vasoconstrictor) and how vulnerable a particular brain is. For more information see Dr. Amen's article High Resolution Brain SPECT Imaging in Marijuana Smokers with AD/HD, Journal of Psychoactive Drugs, Volume 30, No. 2 April-June 1998. Pgs 1-13.

Notice the study without marijuana shows decreased temporal lobe activity (likely from the chronic marijuana usage), but also patchy increased uptake, especially increased activity in the deep left temporal lobe (often associated with anger, irritability and anxiety). The study with heavy marijuana usage shows marked overall decreased activity, especially in the prefrontal cortex and temporal lobes (associated with attention, memory and motivational problems) but also there is a decrease in the overactive areas noted in the "off marijuana" study.

This scan series argues for the possibility of "self-medication," but unfortunately this medication has the side effect of causing the potential for long term damage to his brain.