Psychology in the News

August 16, 2007

Does marijuana make you crazy?

Filed under: correlation, drugs, genes — intro2psych @ 9:50 am

Anyone who has ever seen “Reefer Madness” or survived a middle-school drug education program has probably figured out that there are a lot of exaggerated fears and warnings when it comes to marijuana. And all that hyperbole has evidently not done a lot to reduce the number of kids smoking pot, according to the latest survey.

But recent research has revealed a possible danger in pot smoking that really ought to worry potential users: It might increase your chances of becoming schizophrenic, or otherwise psychotic. Of course, this does not refer to the temporary effects that cause intensive sensory experiences, the illusion of profound thoughts, and an insatiable craving for brownies. The fear is that in some people, marijuana use may trigger a predisposition to a serious mental illness.

Not everyone is buying the argument that the association between marijuana use and psychotic disorders is cause and effect. A student commentary from Drexel University, for example, points out that the purported correlation is small, and that correlation does not imply correlation anyway. Bloggers Paul Armentano and Mitch Earleywine add that there is no new data in this study, only an analysis of previously published data. They also point out that the rate of schizophrenia is remarkably similar from one country to another, despite different patterns of drug use. But I would not go lighting up a joint to celebrate these counter arguments just yet.

Consider first the argument that the relationship is not a whopping correlation, but rather a small but significant correlation. This is exactly what we should expect, if only a small percentage of the population is vulnerable to schizophrenia and similar mental illnesses in the first place. And because the numbers are small relative to the population, we can’t expect big variations in the overall rate of schizophrenia, drugs or not. And the fact that they found this relationship in old data that looked at the broad population, rather than a new study looking at a targeted at-risk population should make us more afraid, not less afraid.

What this meta-analysis is saying is that the relationship between marijuana use and psychosis is strong enough to show itself even in studies that were never designed to look for it. I’m sure someone out there is running a study right now that focuses on teenagers with a family history of psychosis. If there really is a cause and effect relationship, in which marijuana use triggers a pre-exisiting vulnerability to psychosis, this is the type of study that should show big effects.

And what about the argument that correlation does not imply causation? I’m certainly glad that Mr. Gero and others have kept this in mind. Many science news writers seem not to be able to figure out the difference between a cause and effect experiment and a correlational study. But we should also remember that correlation does imply some sort of relationship. I tell my students to think of the two variables in a correlation as X and Y, and to get in the habit of considering three possibilities: X causes Y, Y causes X, or another, third variable (Z) causes both X and Y. In this story, the X causes Y hypothesis is that pot smoking causes psychosis (but probably only in those with a pre-existing vulnerability). The Y causes X hypothesis is that psychosis causes pot smoking. I think we can probably reject this, since the people in question were smoking pot before they became schizophrenic or otherwise mentally ill. A variation on this is not out of the question, though. Perhaps people who are destined to become schizophrenic are already unusual in a way that makes them more likely to smoke marijuana. This is very similar to the Z causes X and Y hypothesis, that some people have a pre-existing condition that makes them vulnerable to both marijuana use and schizophrenia. I see no reason why the first and last hypothesis could not both be true.

So what is the take home message? Should you worry that you might be one of those people for whom pot smoking could cause a lifetime mental illness? If there is a history of schizophrenia in your family tree, the answer is undoubtedly yes. The problem is that it is impossible to be sure that you are safe. We don’t know what might cause the vulnerability, but it is probably in the genes. Even if you don’t know of any schizophrenic relatives, that does not mean that none of your relatives were carrying some of the genes that lead to vulnerability. I hate to sound like a doomsayer, but it is difficult to rule out the possibility that you may be carrying genes that make you vulnerable. In the end, it is a roll of the dice. To me, the payoff seems pretty small in comparison to the risk.

22 Comments »

  1. The debate regarding whether or not people who smoke or smoke marijuana are often more prone to schizophrenia or not is a very complex one. The question at hand is actually regarding whether or not the studies that have been done can be considered reliable, and also if ther data really proves the existence of a cause-and-effect relationshihp of smoking marijuana and having schizophrenia, not just a correlation.
    The major study that has recently been debated in a rather public light took place over 25 years and included over 1000 New Zealanders born in the year 1977. What made the study legitamate in my eyes was the coverage of possible confounding variables that the scientists included in their study. The researchers that did the study factored into their experiment things such as family history of mental illness, and current mental disorders of the patients, and also illicit substance abuse. They also looked at the relationship as a possibly Y causes X relationship, which would mean that having the illness has caused those with it to have a more intensified craving for marijuana. These factors make the findings of this research much more reliable.
    However, there is no doubt that more could be done to go forward with proving that smoking marijuana truly does in some ways cause schizophrenia. It would be of great use to researchers to break their subjects into groups regarding weather or not there is a family history of mental illness or not (assuming that they did not do this in the study previously mentioned). Since schizophrenia is a mental illness that develolps over time, and also because there are so many possible factors that are linked to it, it makes it particuarly hard for researchers to have substantial evidence of a certain reason why schizophrenics are, indeed, schizophrenics.
    As a teenager coming from a generation and even a society where smoking pot is not out of the ordinary, I find it particularly important to pay attention to this study and others of its kind. While health education programs through school systems might discuss the negative effects and possibilities of smoking pot, they do not make it as realistic as the contents of these studies do. It is a scary thought to think that something that, at this point in time, seems so normal and accepted in our culture, could be the cause of such a very serious illness. While it might take time for there to be statistical significance of the findings of these researchers, it would be smart to
    use that time to start considering what evidence they have found so far.

    Comment by Carolyn Crampton — September 8, 2007 @ 5:47 pm

    • man my son has changed soooo much sence he started useing marajuana hes not the intelgent son that he had been he lies steels and lives to tok up sad thers living proof that the shit messes you up

      Comment by pascual — December 2, 2009 @ 8:10 pm

    • This article is actually true. I’m living proof. Im 15 and my grandmother is schizophrenic.. I had no idea about this and smoked weed every day last summer and noticed a big change in the way i saw things. I thought i was smarter when i was high and ended up believe everything i htought cause it felt like it was so right. I developed a false sense of reality even when i wasn’t high. And even recently when i smoke i notice i have crazy thoughts that make no sense at all even days after i smoked… I’m a straight A student and on the right path but its still really really scary to htink that i might have to live the rest of my life with a brain thats not all there

      Comment by none ofyour business — December 23, 2009 @ 1:19 am

      • Indeed “none of your business” you will find that your mind and perception will constantly change on a day to day basis and thus is the evolution of the human brain. It will evolve based on it’s every day experiences, including psychoactive experience, even if you don’t realize you are taking it in, the human brain takes in 500-million bits of information per second, so naturally while on marijuana your brain will be attempting to form patterns of regularity, which goes without saying is a very hard task when your high. Therefore it is not out of the ordinary that you would question your perception when “sober.” I wouldn’t recommend smoking marijuana to anybody that could be considered at a “cognitively immature” stage in their life, if we are ever in a state of mental maturity that is, because overuse can play tricks on your mind and it is important to acknowledge.

        Comment by Peter — July 16, 2010 @ 12:00 am

  2. When my aunt was in high school, she occasionally smoked marijuana with her friends. One day when the joint was passed around, the group of teenagers were unaware that it had been laced with Angel Dust, or PCP (phenylcyclohexylpiperidine) – a hallucinogenic drug which produces similar psychoses to schizophrenia (Jacobs, 1984, p. 29); “hostility, agitation, delusions of grandeur, and auditory hallucinations”. Feldman, Agar, and Beschner (1979, p. 38) describe PCP as the most dangerous drug that exists:

    “Probably no drug, not even heroin, which for 50 years has been considered the monster drug, has been considered more dangerous by drug abuse experts than PCP.”

    That day, my aunt experienced auditory hallucinations of her deceased grandmother and told family members that she was the possessed girl in ‘the Exorcist’, with the ability to control objects and people using her mind. Several months later, with perpetuating mental instability, she was diagnosed as psychotic. Today, over 30 years later, my aunt lives in a mental institution as a ward of the state, having been prescribed many different drugs in attempt to palliate her hallucinations. When I’ve had the chance to talk to her, she appears glazed and removed from the conversation, often pausing for several minutes before replying; perhaps processing information, thinking about something entirely different, or even attempting to block out a hallucination.

    I believe that the scariest fact about marijuana is that someone who buys it rarely knows exactly what they are receiving. It may be mixed with other plants to lower the concentration, sold in an extremely pure and potent form, or even laced with another drug – like PCP. So, whether or not controlled scientific testing results in a conclusion that marijuana can trigger schizophrenia, I think it’s important to remember that independent variables in scientific tests are controlled, whereas what one buys on the street is much less likely to be as pure.

    SOURCES:

    Adams. Does PCP Turn People into Cannibals? March 25, 2005.

    Feldman, Agar, Bechner. Angel Dust: An Ethnographic Study or PCP Users. Lexington Books, 1979.

    Jacobs. Hallucinogens: Neurochemical, Behavioral, and Clinical Perspectives. Raven Press, 1984.

    Comment by Ben Palacios — September 23, 2007 @ 10:27 pm

  3. The news that marijuana may have a big role in triggering schizophrenia is cause for skepticism. The studies that are being used as the backbone for the news are not all new and also are not causation studies but instead studies on the correlation of marijuana to psychosis. Even from the news source there was a comment more about the supposed gateway drug that marijuana is claimed to be than its direct effect on psychosis. It said something along the lines that marijuana my lead some to use other more intense drugs. These drugs include psychedelics such as LSD and psilocybin mushrooms. There may be a correlation but there seems to be no hard fact that marijuana will single handedly cause psychosis.
    Another big factor is that many people turn to drugs such as weed to deal with problems that may be early warning signs of psychosis. Going along with some previously stated facts from this article article 1, marijuana is less likely to degrade the mental stability of a person than alcohol. This brings up the question about why people are so much more concerned for a widely used illegal drug than a legal drug more widely used and abused.
    Marijuana may not be as safe as some claim but there is no clear-cut evidence that it alone causes psychosis. Marijuana may help trigger psychosis in a predisposed individual but it alone will not make somebody schizophrenic.

    Comment by Miles Fineburg — October 4, 2007 @ 7:30 pm

  4. Miles, your comments echo several that were linked in the post. But I still think the evidence favors caution.

    Consider this conclusion by Addington (2005), “After adjustment for age, sex, socioeconomic status, urban residence, childhood trauma, predisposition for psychosis at baseline, and use of other drugs, tobacco, and alcohol, cannabis use increased the risk for young people developing psychotic symptoms.” This was from a prospective study of teens, meaning that they started tracking them before they showed any psychotic symptoms. Some were at-risk based on family history, some were not.

    Comment by intro2psych — October 5, 2007 @ 5:46 pm

  5. The finality of the conclusion of the article that this post is based on is somewhat troubling. For a doctor to say, “We’ve reached the end of the road with these kind of studies” (Robin Murray as qtd. in Associated Press article, 7/27/07) when earlier in the article the researchers concede, “they couldn’t prove that marijuana use itself increases the risk of psychosis.” (Associated Press, 7/27/07) The study seems to be far from concluded. It seems safe to say that marijuana use as a young adult does indeed increase one’s chances of developing schizophrenia, but we must dig deeper and discover why this is, what happens on the level of the brain that causes this to happen.
    Researchers Tina Hesman and Matthew Franck, in a report published in the St. Louis Dispatch , say that in adolescent years the brain is going through massive transitions from the child brain to the adult brain and an unsuccessful transition can cause mental illness. They go on to report that “severe mental illnesses have roots in the developing teen brain…even if symptoms aren’t seen until years or decades later…Some may turn to drug and alcohol use to help ease the pain, leading to run-ins with the law” (Hesman & Franck, 2006).

    Here we have our Z causes X and Y scenario. The failed transition of a maturing brain predisposes one to mental illness and also to marijuana use as a form of self-medication. Although the use of marijuana can increase one’s chances of becoming schizophrenic, the story does not end there. A maladjusted brain can bring both psychosis and marijuana use. So to say that the end of the road has been reached with this topic is foolhardy, for there is much to be discovered about the correlation between the two.

    SOURCES:

    Hesman, T. and Franck, M.(2006, January 31). “Are Teens Out of Their Minds? Maybe” St. Louis Post Dispatch. .

    Associated Press, London (2007, July 27). “Marijuana May Increase Psychosis Risk, Analysis Says”.

    Comment by Connor O'neill — October 21, 2007 @ 2:21 pm

  6. I know for certain it can definitely trigger mental health problems like extreme paranoia, panic attacks and anxiety in some people.

    But it can also be beneficial for the same problems too. They really need to allow full study of it and then figure out how to put it in a pill, because smoking it is really not the answer for medical use.

    Comment by tiko — June 3, 2009 @ 3:25 am

  7. There is a pill already – it’s called Marinol and its prescribed mostly for cancer patients and those suffering from anorexia. It contains tetrahydrocannabinol (THC), the primary psychoactive ingredient found in marijuana. However, there are several differences. The marijuana plant exists in many different strains, all with hundreds of varying amounts of psychoactive compounds. A medical marijuana patient who benefits from one strain will not necessarily benefit from another. Since Marinol contains only THC and lacks the cannabinoids present in the plant, the high is undoubtedly different, with many describing it as more psychoactive and therefore less comfortable for some.
    Furthermore, the effects of smoked marijuana are usually felt within minutes, while Marinol must be ingested and metabolized. This makes the high similar to that of eating weed edibles such as brownies, generally described as a much more intense high and often linked to more paranoia than normal. Ingesting the THC and having to wait for the effects makes it harder for a patient to know how much they need to take; with smoked marijuana they can effectively get high enough to only relieve symptoms.

    Comment by Paulina Marie — December 15, 2009 @ 4:09 pm

  8. This article is actually true. I’m living proof. Im 15 and my grandmother is schizophrenic.. I had no idea about this and smoked weed every day last summer and noticed a big change in the way i saw things. I thought i was smarter when i was high and ended up believe everything i htought cause it felt like it was so true. I ended up developing a false sense of reality even when i wasn’t high. It’s really scary to think about it now but i was in a diff. world where my outlook on life was completely different. but after i quit for a while it started to go away. And even recently when i smoke i notice i have crazy thoughts that make no sense at all even days after i smoked… I’m a straight A student, trying hard not to smoke, and on the right path but its still really really scary to htink that i might have to live the rest of my life with a brain thats a little physiotic. It’s not a noticable amount i just notice myself thinking things that arn’t true and that are complete bull shit but it feels like all your other thoughts. So if you smoke weed and start to notice a difference in the way you think and shit then i strongly urge you to reconsider smoking weed, there are so many other better things in life that cna make you happy…

    Comment by none ofyour business — December 23, 2009 @ 1:27 am

  9. “This article is actually true. I’m living proof. Im 15 and my grandmother is schizophrenic.. I had no idea about this and smoked weed every day last summer and noticed a big change in the way i saw things. I thought i was smarter when i was high and ended up believe everything i htought cause it felt like it was so true. I ended up developing a false sense of reality even when i wasn’t high. It’s really scary to think about it now but i was in a diff. world where my outlook on life was completely different. but after i quit for a while it started to go away. And even recently when i smoke i notice i have crazy thoughts that make no sense at all even days after i smoked… I’m a straight A student, trying hard not to smoke, and on the right path but its still really really scary to htink that i might have to live the rest of my life with a brain thats a little physiotic. It’s not a noticable amount i just notice myself thinking things that arn’t true and that are complete bull shit but it feels like all your other thoughts. So if you smoke weed and start to notice a difference in the way you think and shit then i strongly urge you to reconsider smoking weed, there are so many other better things in life that cna make you happy…”

    this is exactly what happened to me. everyone was avoiding me and for some reason i thought it was because they all were crushing on me. i stopped last friday and im still really stupid… i hope this isnt permanent T_T

    Comment by nicole — May 26, 2010 @ 6:41 pm

  10. you got to like that for every study that says weed is bad ther are hundreds that show the oppisite.

    Comment by thetruthis — August 10, 2010 @ 2:22 am

    • Alcohol is the reverse of that. Look which ones legal and socially acceptable…

      Comment by Reality — April 9, 2012 @ 12:09 am

  11. it is dangerous to a small minority of people really, but those people are already suffering mental illness. It could also bring out the mental illness in some people. It’s an hallucinogen, unlike LSD, but it is still a very powerful mind altering substance and I think some people smoke too much and are delusional, they argue for legalization with faulty logic and little concern for the small minority that could make their lives hell. We have a burdern to society and just because you don’t get ill from it, you should care about how it could make some vulnerable people ill. It can, people claim it’s mild but it’s a very powerful mind altering substance and for some people they get delusional, think everything they think under the influence is profound, come to crazy religious thoughts, get fanatical, and illogical. It depends on the person but it’s not safe for everyone and should not be legal but medically it does have benefits for some people and should be up to a doctor to determine if it can help them.

    Comment by meh — September 14, 2010 @ 10:59 pm

  12. my friend is gay,and he was molested when he was younger. Whenever he smokes weed he’ll have these split personalities and one eye will turn into his head and hell talk about how he buried 7 children and hell call me a stupid slut and hell kill me if its the last thing he does. He will also scream and his body will almost convulse. He never has done any harm to me but he will grab me and grab me by my hair or he will come at me snarling. Is this a disease or is this something like demonic possession?

    Comment by amanda — October 16, 2010 @ 10:41 am

  13. I had a friend recently who got a hold of some bad marijuana that put him in the mental hospital..now is out telling everybody he talks to his daddy that has been dead for years and he thinks people are watching him. It’s best to stay away from marijuana all together because people put things in it and also some is so potent that i will mess you up for life. Now is has to take medicine in his daily life. People please don’t use drugs period.

    Comment by Marijuana Is BADDDD!! — November 16, 2010 @ 4:38 am

  14. “The Illusion of profound thoughts…”

    Carl Sagan (1934 – 1996), the world renowned astronomer, astrophysicist, cosmologist, who published more than 600 scientific papers and popular articles and was author, co-author, or editor of more than 20 books, was an advocate of legalizing Marijuana.

    You claim the insights are “illusions”?

    Consider: Carl Sagan solved one of the greatest equations of his lifetime while HIGH.

    And if you think he is alone, you are fooling yourself.

    I know a professional author who has used marijuana to deepen his writing, and has produced some truly exception essays while stoned. He explains it as being relaxed and focused at the same time, more in touch with his own thoughts, more able to perceive what he wants to say, and then the words just flow out of him without pause for doubt. His work is coherent and extremely well received.

    If you’ve never experienced it, than you cannot claim that the insights one gains while in the proper mindset aided by this ancient herb are “illusions.” With respect, you have no basis for comparison. Or perhaps you’ve just been smoking year old shake. ;)

    Comment by Ryan Ray — July 27, 2011 @ 3:05 pm

  15. It is important to note that many of the times its due to bad batches/ aka weed being laced with something else, like the above comments have stated. My parents always tell me stories of people getting bad batches and going mad.
    The thing is, if marijuana was to be legalized this would eliminate this problem. You would no longer have to buy from strangers, you would be buying from reliable dealers.

    Comment by Jimmy James — April 9, 2012 @ 12:04 am

  16. I would like to share with you my story. The first time I tried weed I was fourteen and it was with my boyfriend and his friend. I litterally went crazy out of my mind and I could barely walk, I fell all over the place and my boyfriend tried to help me but him and his friend were laughing because they had never seen someone act the way that I was acting. I remember after all of it he was like, Dude no one acts like that no one ever has. So..I continued to smoke for a while, a few months. But something changed in me. I wasn’t me anymore. I started to shake uncontrollably every time we smoked after that, I can remember begging him to hold me, tell me story’s, keep talking, don’t let me die. And everything was okay after the high went down. Even though I felt that way I continued to smoke. And everything went bad, I had anxiety every day. I crawled into my 51 year old fathers bed and made him hold me while I cried. I slept in his room for maybe a week on the floor. It was a mental disorder that I tried every day to get rid of, by myself no pills. I felt my mind was eating me away. I felt like I was falling down a dark hole and no matter how hard I tried to escape my thoughts they kept coming back. “Am I going to die?” “Whats this life mean?” “Why do we have trees?” “Are there aliens?” the stupidest questions. I got depressed. Cried everyday. And so I quit. Stopped. And I’m glad I did. Thrilled actually. I’m fifteen now and all that happened months ago. I used no pills to help, saw no doctors. I struggle but I keep my mind off things. And I am better…still don’t feel like myself though. I just want to be a kid again…I dont want to hurt anymore. I still wonder off. Still lay awake wishing I never tried weed.

    Comment by Natasha Williams — June 6, 2012 @ 11:39 am

  17. idk but I think I may have had one of the worst, most unheard reactions from smoking weed. I’m 19 and it all started a year add a month or two ago. I had smoked three times previously, all pretty potent stuff. Then one day I smoked what was probably the most potent pot i had ever smoked called trainwreck. Long story short, i went bat-shit crazy, I mean strait-jacket crazy. I naturally have the tendency to think a lot and wonder away to my own little world at times, and it was like my thoughts were being multiplied by a million. Like someone poured gasoline on my brain and set it on fire. It was excruciating to say the least, i tried to kill myself to make it stop but luckily my friends were there to help me. On top of all this i threw up a few times and my nose bleed. I begged for them to take me to a hospital or bring in an exorcist. Anything. The things I was saying and thinking weren’t making since. I was most often repeating in my head no more red, no more red, no more red.” Which i guess meant no more weed. Eventually they drove me to a spot and my friend held me until I calmed down. The whole time I was saying crazy shit about God and religion and someone asked me If i had ever been sexually abused as a kid and even though I definitely haven’t, I began telling crazy false stories about how basically everyone and their mother abused me. Eventually I came down but the following few months I had intense paranoia, depression and, life seemed unreal. I was sleeping with a light on. The only thing that stopped me from committing suicide was religion(islam) and the simple fact that I was still pretty grateful that I had made it through that nasty experience the last time I smoked so I figured life could only get better from there. I got past most of that but I still struggle, mostly from thinking about what happened that night- it haunts me and I have fears that somehow- even though I’m not smoking that it’ll happen again or that that will be my punishment if I go to hell(it was so bad that I thought I had possibly died and gone to hell while it was happening). All this is mainly because I have no idea how or why that happened to me but long story short- weed has different effects on people so I don’t recommend it for anyone- go to church, the mosque, temple or whatever spirituality you believe in and live a good, clean, simple, happy life and enjoy the good things in it- not the bad things.

    Comment by Akim Smith — January 6, 2013 @ 1:52 am

  18. I have smoked a lot of marijuana in my life. Paranoia is/ was my main issue I could never figure out how to be un paranoid until I started linking thoughts ( I call that using your brain I never do that) once I started putting things together I thought about life and death (while under the influence) what might be after life what may have been before. Creation an everything. Marijuana opens your mind and i became un paranoid by being honest with the people around me. I was ashamed of my habit. I believe marijuana can make u feel Insane but that’s atleast for me because I didn’t know what I believed in. I have a lot more that I’m willing to share or talk about on the topic of marijuana

    Comment by Christian — January 26, 2013 @ 6:00 am


RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

The Silver is the New Black Theme. Blog at WordPress.com.

Follow

Get every new post delivered to your Inbox.

Join 40 other followers

%d bloggers like this: