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Remember Kids, Whatever You Smoke, Your Brain Smokes Too

I’m sitting in front of my laptop at 3 in the afternoon, wearing pajama pants, with Nacho Cheesier Doritos dust on my fingers. (Cheesier than what?) I know what you may be thinking, but sadly, no, I am not high. If I were, this blog would probably be funnier.

I used to smoke pot in high school, but I quit because it started making me so anxious, it wasn’t enjoyable anymore. I know a lot of people who still smoke — a lot — and I’ve generally been on their team when it comes to the whole “smoking weed isn’t dangerous, it can actually be good medicine” argument. We all know about its ability to conquer nausea, reduce the ocular pressure associated with glaucoma, and even alleviate chronic (no pun intended) pain. And other than something my grad school neuropsychopharmacology (impressive, huh?) textbook calls “amotivational syndrome,” the scientific establishment hasn’t made a good case for why people shouldn’t light up every now and then.

But, alas, a new study presented at the Society for Nuclear Medicine’s annual meeting shows that there is a measurable, significant difference between the brains of potheads and those who just say no. Using molecular imaging — injecting subjects with a radioactive isotope and then looking at brain activity in a positron-emission topography scanner — researchers noticed that “marijuana users,” as they call them, have about a 20% decrease in active CB1 cannabinoid receptors.

What does this mean for you? Well, CB1 cannabinoid receptors are one of the places THC binds when it makes its way up into your noodle. They are responsible for making you feel high, but they also seem to have an effect on sense of time, memory, coordination, concentration, and even lasting feelings of pleasure. With less of these active receptors to work with, it is unknown whether smokers actually experience losses in these areas, or if they are able to simply work with what they’ve got. What is known, as the authors of the study report, is that if you quit smoking pot for just 30 days, your CB1 receptor activity will markedly increase, almost back to baseline levels. And I’d venture to guess that the next time you took a bong hit, you’d get really, really high.

Reference: Society of Nuclear Medicine (2011, June 13). Chronic marijuana smoking affects brain chemistry, molecular imaging shows.


Cara’s Twitter: @CaraSantaMaria
Cara’s website:

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  1. Hector says:

    Why do you think potheads would be angry after reading this post? It’s not like this was anti-legalization propaganda. Even as a stoner I appreciate and value this information. I much rather be an educated stoner who understands how marijuana works than the stereotypical hippy smoker.

  2. Natalya says:

    I am admittedly biased towards recognizing the positive effects of smoking bud.

  3. Natalya says:

    I disagree with commentators who argue that researching the effects of cannabis on the brain is a waste of time and money. One poster mentions that diseases like schizophrenia and dementia are difficult to understand. While I have no expertise in dementia, I do work in schizophrenia research and did a stint in addictive disorders research. It’s my personal opinion that few diseases cause as much suffering in their victims as schizophrenia and schizoaffective disorder. Schizophrenia predicts terrible outcomes in patients. The positive symptoms of schizophrenia and schizoaffective disorder, delusions, hallucinations, and disorganized thinking are the symptoms most people associate with schizophrenia and schizoaffective disorder. They occur during psychotic episodes, and though there is no cure nor any medication on the market that has a 100% improvement rate and thought they often cause unbearable side effects, there is no doubt that several atypical antipsychotics can shorten the duration of psychotic episodes and in some cases, prevent them. The number of clinical trials demonstrating this is quite large, and the correlations are statistically significant. However, the negative symptoms, like flattened affect (inability to feel or show emotions), alogia (deficits in production and fluency of speech), anhedonia (lessened interest and ability to feel pleasure), and avolition (inability to engage in productive or goal-directed behavior, mentioned above as an effect of cannabis use) are more debilitating, cause lower GAF scores, poorer outcomes in patients, and unlike positive symptoms, are not treated by neuroleptics or other psychiatric medications on the market. Likewise, therapy is of no use when dealing with negative symptoms. What does this have to do with marijuana? Several fascinating studies are demonstrating that cannabis use by schizophrenic patients may be beneficial in several ways. It seems to shorten the duration and diminish the frequency of psychotic episodes, according to the Department of Psychiatry at the Nelson R. Mandela School of Medicine, and that same group of researchers suggest that cannabis use may also reduce negative symptoms! Louisiana State University’s Department of Psychiatry also found that cannabis use was associated with lowered severity of negative symptoms. Furthermore, a meta-analysis done by scientists at The Institute of Medical Sciences at the University of Toronto found that schizophrenic probands who used cannabis performed better than non-users on a battery of neruocognitive tests. Researchers at at Charité-Universitätsmedizin Berlin’s Department of Psychiatry and Psychotherapy Melbourne Neuropsychiatry Centre at the University of Melbourne and Melbourne Health published studies demonstrating that cannabis use was associated with higher cognitive functioning in schizophrenic patients. So why is the study about CB1 receptors that Cara mentions important to understanding schizophrenia? The Department of Psychiatry at the University of Pittsburgh published a study indicating that unlike the decreased reactivity of those receptors in healthy brains and the brains of patients with Major Depressive Disorder potentially caused by pot-smoking, schizophrenic brains may have higher CB1R levels caused by bud. Thus, not only is research on marijuana use incredibly important to treating schizophrenia’s symptoms and improving outcomes, but identifying the way specific receptors are affected by pot can help us better-understand the incredibly complex causes of a devastating disease.

  4. Cronic says:

    I don’t give a flying fuck about what studies say pot is the shit it is Esaly better for you than alcohol or meth or herowin

  5. Bodyguard for the Brain: Researchers Identify Mechanism That Seems to Protect Brain from Aging – ScienceDaily (July 13, 2011) — “Researchers from the Universities of Bonn and Mainz have discovered a mechanism that seems to protect the brain from aging. In experiments with mice, they switched off the cannabinoid-1 receptor. As a consequence, the animals showed signs of degeneration — as seen in people with dementia — much faster…. The animals with the intact CB1 receptor, to the contrary, did clearly better with regard to their learning and memory capabilities, as well as the health of their nerve cells.”

    Maybe Cara SHOULD get stoned and keep reading…

  6. Outraged Stoner says:

    Uh yeah, you have to check yourself before you wreck yourself. Nobody should smoke anything, it is primitive and horrible for the cells in your airways, vapor is the new smoke. Intoxicants have been and will always be consumed in our culture, it is all about responsible, educated moderation. Which is why I find it odd that the study cited claims that it “may prove critical for the development of novel treatments for cannabis abuse.” Couldn’t this problem be cured by eliminating the black market drug culture, teaching parents how to be parents, and by placing professionals in society to educate, regulate, and moderate the drug use of those choosing to do so? It would be nice if all of the studies investigating our cannabinoid receptor systems were aimed toward developing novel treatments for horrors like cancer but I just bought a cake so… at least they are doing the research!

  7. Anonymous says:

    Hey Cara – Do you still smoke cigarettes? Your brain smokes those, too.

  8. Fred says:

    So, giving up weed for Lent will make for a really good summer?

  9. JD says:

    @Zach Thank you for apologizing for the stereotypes. Your point is taken.

  10. Zach says:

    My apologies for resorting to use of narrow stereotypes in my response. It muddled my point and may have inadvertently villainized smoking.

    What I think is important to consider is that non-experts (including myself) can often fail to see the relevance or implications of such work that verifies conventional wisdom. Understanding neuropharmacology of drugs of abuse can help us get a better hold on normal and disease states of the brain. While I can assure you that NIDA/NIMH/NIH do not just simply hand out money, there is plenty of work going on in areas like you suggested. Unfortunately, disease states like schizophrenia, dementia, etc. have few easy answers. I’ll gladly take a quantitative effect, such as seen here, any day of the week if it gets us one step closer to cracking this sucker (the brain). Have the best day, man.

  11. Lenny says:

    @Oh, Lenny… Haha University of North Texas is a crappy Teir 4 College, high value intellectuals like Dr Phil went there and studied psychology . I wouldn’t go there. Everyone knows a masters in neurobiology is a 1 or 2 year max course and it isn’t worth a damn in the real world unless you get a phd.

    University of PA grad, 6 figures per year and I didn’t have to sleep with Bill Mayhar. Who’s the chump?

  12. SrRealist says:

    for the majority of that article i thought i was going to learn something new about my favorite herb. but, as tuffhippy already mentioned, this is just the scientific backing to what happens when we “users” take whats known as a “tolerance break”. any long time stoner will tell you that the more you smoke the more you need to get high, and if they’re a SMART long time stoner, they’ll stress the importance of a tolerance break.

    i appreciate this study and the post here though. the progression of scientific studies into psychotropics of any kind is a must in my eyes.

    hmm, how to close… smoke weed every day? (then take a few weeks off)

  13. JD says:

    @Zach My friends and I all work and do well in our various schooling. We work hard, and when not working we go and do things. Create things. (No not bongs) But thank you for assuming we all sit around and do nothing. But couldn’t the money spent on testing a drug that has been used by millions be better spent on important research? We don’t need to know exactly which piece of the brain this works on. It has obviously not been killing people left and right. How about spending time on curing diseases or testing exactly how the brain is reacting and the hormones involved with a person going insane so as to create better medications and treatments? No, instead of those things these men and/or women focused on pointlessly watching the brain function of a stoner. All I was trying to say is that the money could have been better spent on a REAL issue. Have a good day sir.

  14. dangeraardvark says:

    Oh god, no! Not my cannabinoid CB1 receptors! Those are my favorite receptors!

  15. Zach says:

    To the stoners claiming this was a waste of money: When you and your buds can tell me exactly what, where, and when things change in the human brain (or the rest of the body) after smoking, as indicated by the results of your rigorous couch sitting, I will gladly buy you a lifetime supply of whatever munchie you want. Do you really feel that understanding how the “#1 illicit drug choice in America” affects the human body is a worthless pursuit?

  16. Rhoda says:

    I would be interested in knowing what effect marijuana has on the lungs, kidneys and other body parts, apart from the brain. We all know how it makes you feel, but what are the longterm side effects/damages lighting up this drug of choice brings?

    Never smoked, just wondering.

  17. Hi Cara! Nice post!

    Question: You wrote that after 30 days sans buddha, active CB1 receptors increased to ALMOST baseline levels.

    Is there any indication in the study that there might be permanent sub-par CB1 activity after hardcore usage?

  18. Bradhole says:

    I’d guess that MOST people, stoner or not, who listen to or read Nerdist are at least slightly smarter than your typical wake and bake stoner. Most people who I know who smoke their happy-smoke regularly are pretty stupid. More so than they were before they started smoking. I’m referring to people who basically live for their next bowl. Almost as if they were addicted or some crazy nonsense like that.

  19. Oh, Lenny... says:

    Lenny, according to Ms. Santa Maria’s website:

    “When she was only twenty years old, Cara graduated cum laude from the University of North Texas, where she studied psychology and philosophy. She went on to earn her M.S. in neurobiology in 2007.”

    Tell me, what is it that you do again? Chump.

  20. Ryan says:

    You know the difference between this and *Every Other Drug*? It’s not permanent, and, if you’re smoking responsibly (ich means not lighting up 3 or 4 times a day) you can, with a tiny bit of trouble, admittedly, stop whenever you want.

  21. Lenny says:

    Sounds like Ms. Santa Maria has “Amotivational Syndrome” herself without the use marijuana sitting at home at 3pm eating a bag of Doritos.

    Get a real job.

  22. Dave OH says:

    Of course you brain adapts to chemicals it encounters, you are alive. Receptors are upregulated or downregulated all of the time in response to ligands. Just like tuffhippy says

  23. JD says:

    Me or any of my friends could have told you this much.

    This study was a waste of money and effort.

  24. Wayne D. says:

    Take holidays. As with anything, take time off from it from time to time.

  25. tuffhippy says:

    Okay, so this study says the more you smoke, the higher your tolerance, and if you should happen to take a few weeks off, your tolerance will be lower? um, how much did this study cost? I could’ve told them this about ten years ago.

  26. David says:

    I did that, I didn’t smoke for a while (after I got arrested lol) and then smoked again… The high was incredimazejob! Now I like to smoke about once a week and it blows my mind every time! So I believe that..

    One time I was so high, I laughed at Family Guy!!

  27. Gabe Levine says:

    Well, that’s not a terrible negative side effect. Still better than alcohol at least.

  28. Mathew says:

    Nicely put mate, I had almost 3 years off smoking, moved to Toronto from Australia and couldn’t resist the urge. I was on a 2 week break, now I will extend that to a month, much to the dislike of my dealer. Ignore any nasty emails detailing the downturn of his ‘business’.

  29. Walker says:

    I smoked a lot at the beginning of college, until a college tharapist told me that I kept coming in and telling her that I smoked a lot of pot, and that I was sad. She suggested there might be a connection between the two. I don’t smoke, but I always liked the South Park formulation of problem. Pot doesn’t lead to heroin, or fund terrorists, but it does make you okay with being bored, and that is sort of lame. I had a lot of hobbies before I started getting high, and it took me a year or more to pick these hobbies up after I stopped getting high. I have a lot of friends my age (28) who still smoke, and more power to them. It certainly shouldn’t be illegal, and sick people should have access to it, but for me, pot is stupid and I am glad I don’t smoke it anymore..

  30. Adam M O'Neill says:

    @Bradhole Did you really just use the words “outraged stoners” unironically?

  31. Damian says:

    Can’t wait to see all the comments from the anti-stoners for a post that still casts weed in a good light overall.

  32. Bradhole says:

    Can’t wait to see the comments from outraged stoners.