When Science Goes To Pot
    By David Sloan | January 1st 2013 10:35 AM | 32 comments | Print | E-mail | Track Comments
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    David is a neuroscientist in the field of sensory-limbic circuitry. He published his debut novel, [Brackets], in October 2012. He is a member of...

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    Disclaimer: I have never smoked pot. Not interested. But, I have been very interested in the decades-old debate about it. On one side you have people who claim it as a benign, useful substance that should be legal. On the other side, you have people who claim it is a dangerous and destructive and should be banned. I was surprised to realize to myself recently that I couldn't articulate a good argument for either side. I didn't know enough. 
    So I wanted to do an experiment. But not that kind of experiment.

    I wanted to play out the following hypothetical scenario that would never, ever happen in real life. I will describe it in story form. There is this person-- we'll call him Jimmy-- and someone offers him a joint in a dorm room. Jimmy has never tried it before and doesn't know very much about it, so he asks his friend if he could take a few hours to research marijuana on the NIH's biomedical research database PubMed before making up his mind. His friend is cool with that, so Jimmy runs up to the computer. He searches peer-reviewed journal articles exclusively. No Wikipedia, no Google, no blogs (sorry), no specialized sites. He just wants the pure, unadulterated good stuff of science. What would his decision be?

    Well, the first thing Jimmy would find is that it isn't easy to research marijuana. Based on PubMed topic results by year, 2012 showed a record high of journal articles published that had something to do with marijuana (as examples, marijuana pubmed search results in 2000: 401. In 2012: 1275. Cannabis search results in 2000: 204. In 2012: 853). So, to make it practical for him to learn something in a few hours, he restricts his search to articles published in the last decade at most. He further restricts the articles he clicks on to those that have to do with the actual action of marijuana. He passes on all the social science, since he knows social scientists just make stuff up.

    The first useful article he comes across is a good one: Micale et. al., published Dec 2012 inPharmacology and Therapeutics. In the article he learns the basics. The primary active component in marijuana is delta-9-tetrahydrocannabinol (THC), a lipid which acts as an agonist (activator) for receptors CB1 and CB2 in what is called the endogenous (naturally occurring) endocannabinoid system of the body. He further finds that THC is one of between 70-100 "terpenophenolic pharmacologically active compounds" found in Cannabis sativa which don't have the same psychoactive action as THC, but which interact with the body in different ways. He reads that the acute action of THC is antidepressive, anxiolytic (anxiety reducing), and stress relief, and can facilitate fear extinction.

    So Jimmy thinks, Oh, that's all good. He further reads that "high doses or rapid administration of Δ9-THC as well as chronic Cannabis use are associated with transient psychotic syndrome, panicogenisis and bipolar disorders..."

    Uh oh. 

    Further reading shows that the effects can be very subjective based on a range of factors. OK. He also notes that the study of the endocannabinoid system is a target for people developing drugs specifically for mood disorders, but that the research has been hit or miss. In one study, use of a CB1 receptor antagonist to treat obesity was stopped because of evidence of increased depression, anxiety and thoughts of suicide (Van Gaal et al. 2005), and that led to the shutdown of similar studies in ensuing years for links to depression and anxiety. But the authors note that there's still hope for discovering the right compound.

    Elsewhere in the article, it describes the location of CB1 and 2 receptors. CB1 is primarily in the brain, at high concentrations in the basal ganglia, frontal cortex, hippocampus and cerebellum (motor, decision making and memory systems), and low density nearly everywhere else. It's found primarily in GABAergic (generally inhibitory) neurons, but also in glutamatergic (excitatory) neurons and glia (non-neurons).  CB2 is also found in the brain, but also in immune tissues and inflammatory cells, including the spleen, and is in lymphocytes and macrophages.

    Clearly, Jimmy wants to learn a little bit more about this THC compound, because clearly, if those systems get screwed up, it could be bad.To find out more about THC, he searches and runs across D'Souza et. al. 2005. This study injected 2.5 or 5 mg of THC directly into the blood of adult subjects who had tried marijuana before, and then measured all the dose-dependent effects on the subjects. They found that the effects of THC peaked after ten minutes, had effects that were "not severe", and then dissipated by 200 minutes.

    Jimmy thinks, Oh, good, so the effects are temporary. Then he reads the extensive list of observations about the patients. They say the subjects showed "the quality of symptoms showed similarity to the positive symptoms reported by schizophrenia patients".

    What? The subjects were also: less spontaneous, internally preoccupied, showed blunted affect, "spaced out", detached, saying bizarre things, had distorted time perception, feelings of unreality, altered body perception, somatic concern, guilt, tension, uncooperativeness, unusual thought content, and poor attention. Measures of anxiety and tiredness were up during the peak time, and feelings of calm actually went down. Feelings of panic didn't go up significantly, although one person had to drop out of the study because of a panic attack. No long-term medical affects were noted in the group. 

    So, at this point, Jimmy is weighing the possible experience of the mind alterations with the repeated comparisons made with psychosis. But he notes that that study is just for straight-up THC. What about all the other compounds? Well, further searching shows that the second-most studied compound seems to be cannabidiol (CBD).

    To his great interest, he finds papers like Bhattacharyya et al. 2010, which demonstrate that CBD actually has actions that counter the effects of THC. It is anxiolytic, perhaps even antipsychotic, has no memory effects, and is being investigated for pharmaceutical use, but how it works isn't clear yet (though it might involve 5-HT seratonin receptors).

    So Jimmy reads this and thinks, Awesome. If marijuana contains both chemicals, they might cancel out the more severed effects of THC, making it a better experience. But then a quick search to find work measuring the relative abundance of both chemicals in marijuana produces Potter et al. 2008, which points out that available forms of cannabis have been used to promote the concentration of THC and the decrease of CBD so that the psychoactive effects are stronger, often with CBD containing less than .1% CBD in forms with concentrations of 4 to 14 to 40% THC.


    By this time, Jimmy is getting tired of staring at the screen, so he starts searching more haphazardly. He finds that THC helps to keep inter-ocular pressure down in glaucoma patients, but he doesn't have the patience to find out why. He finds that there really aren't any recent papers specifically linking marijuana and addiction. The literature seems much more concerned with what happens when people with mood disorders, schizophrenia and other substance abuse addictions also use marijuana.

    Jimmy wonders if there is a link between marijuana and cancer, and he finds Hall et al. 2005 which suggests that there may or may not be some association with respiratory system cancers, and points out that THC lowers feelings of nausea and increases appetite and eases pain (although Lee et al. pointed out this week that it isn't an actual analgesic; its affect is more at the higher levels of perception), making it a possible treatment for chemotherapy patients. And then he finds Larson et al. 2012, which reportedly confirms a link between marijuana use and a risk of tumors in the testes. That gives Jimmy a little pause. You don't mess with Jimmy's testes.

    He wanders around to find out more about THC affects outside of the body, and runs across the findings of Karmaus et al. 2012 (both of them), which report that THC suppresses the inflammatory lung response to influenza, and has an effect on T-lymphocyte activity that operates independent of CB1 or 2 receptors. Now, both studies were done in mice, and Jimmy is no mouse. But it gives him pause.

    Jimmy has to admit that Pubmed doesn't make marijuana sound very appealing. He tries searching "cannabis pleasure" and comes up with Cassidy et al., but by this time he's so tired of looking at the screen that he can't figure out exactly if the paper is helpful or not, because its more interested in how psychotic people feel about the anticipated pleasure of marijuana use compared to controls, and Jimmy isn't psychotic. Yet.

    So, the result of roughly four hours of Pubmed searching came up with some interesting results. The reader is invited to try the same experiment and see if the overall impression of the appeal of marijuana is different using different search criteria and objectives (again, using only the science). Again, it's doubtful that anyone would ever take the time out to do research on pot when offered it, and if they did, they would go to far more accessible (and biased) parts of the internet.

    You may be wondering what Jimmy did in the end. I'll tell you. His head got so fuzzy from all that research that he gave up and started browsing YouTube videos. Six hours later, he realized that he had forgotten all about his friend, and that it was 3 in the morning, and he resolved to seek help for his internet addiction by joining an online support group. But he never inhaled.


    What is the point of this article? You claim to be interested in the question of harm, but paint it simplistically in black and white. Then you pretend to not know what a review article is, or to be aware of all the special commissions that have done the homework for you, repeatedly, across the globe throughout recent decades, that have all come to similar conclusions. I'll help - they universally conclude that prohibition is not warranted, but that some harms do exist (although mainly as a consequence of heavy, sustained use). Of course, it is easy to cobble together a case for either simplistic side by using a handpicked selection from the thousands of papers that have been published. But what is the point of that? The only interesting question left is "why is cannabis still prohibited? why do governments not follow the advice of their own commissions?"


    Ah, but that is not the point of this article at all. The point of this article is not to make a case for or against the legalization or decriminalization of pot. The goal was to see exactly what would happen if the most recent science on the subject was viewed objectively, viewing things from only the very tip of the many decades of research that have accumulated to this point, without any cultural or social context (although the reason there are so many articles about this in 2012 is because of the cultural and social context). My discovery was that, from that specific viewpoint, the impression that one would get is that smoking pot would be very uncomfortable, if not scary, proposition. Now, you may not agree with that assessment; you may not have had the same response to the terms used in the articles I read as I do. Let me pose you a very subjective question to illustrate why I thought this experiment in literature was interesting: why, if marijuana is continuously discussed as a benign, relatively harmless, even positive experience, does the scientific language describing the effects of marijuana seem so negative? Is that my personal bias of the reading, is it the bias of the scientists or scientific language, or is there something legitimately negative about the experience of smoking marijuana? And by the way, in response to your understandable accusation that I hand-picked the articles I presented to present a certain point of view, I can only state that I attempted to restrain myself from any such bias. I believe the search terms I used in the order I used them were appropriate to my hypothetical case, and I didn't select any Pubmed articles that weren't on the first screen to come up for a search term. In other words, I didn't scroll around for the best ones. Just the ones that were relevant to the topic and at the tops of the lists. 
    Gerhard Adam
    Well, here's the problem with "objective".
    *******  is LIKELY SAFE for most adults when used appropriately. ******* can cause insomnia, nervousness and restlessness, stomach irritation, nausea and vomiting, increased heart rate and respiration, and other side effects. ******* can make sleep disorders in patients with acquired immunodeficiency syndrome (AIDS) worse. Larger doses might cause headache, anxiety, agitation, chest pain, and ringing in the ears.

    Large doses may be UNSAFE and can cause irregular heartbeats and even death.

    Bleeding disorders: There is concern that ******** might aggravate bleeding disorders. Use ******** with care if you have a bleeding disorder.

    Heart conditions: ******** can cause irregular heartbeat in sensitive people. Use ******** with caution.

    Diabetes: Some research suggests that ******* may affect the way the body uses sugar and might worsen diabetes. But the effect of ******** and herbs has not been studied. If you have diabetes, use ******** with caution.
    Then we also have.
    Tell your doctor immediately if any of these unlikely but serious side effects occur: easy bruising/bleeding, difficulty hearing, ringing in the ears, change in the amount of urine, persistent or severe nausea/vomiting, unexplained tiredness, dizziness, dark urine, yellowing eyes/skin.

    This drug may rarely cause serious bleeding from the stomach/intestine or other areas of the body. If you notice any of the following rare but very serious side effects, seek immediate medical attention: black/tarry stools, persistent or severe stomach/abdominal pain, vomit that looks like coffee grounds, slurred speech, weakness on one side of the body, sudden vision changes or severe headache.

    A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

    This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

    These two drugs are caffeine and aspirin, both ingredients in Excedrin.  Do any of these sound particularly appealing?  I also only chose the two immediate posts from Webmd.

    For the record, I don't use marijuana, but the appeal should be obvious, in that millions use it without coercion, just like alcohol [which is also a toxin]. 

    Mundus vult decipi
    Gerhard, I absolutely agree with your point. Most drugs that are taken regularly have the possibility of side effects. In fact, this is reinforced to me every time I have to sit through a 2 minute pharmaceutical commercial on Hulu for a drug I'll never use (thanks for that, drug companies!) But that's an aside. 
    The warnings about caffeine and aspirin are legitimate, and bad things have happened to people who have overdosed or used them in some incorrect combination. But marijuana is a different case. In the case of Excedrin, those things are possible side effects, not descriptions of what the drug does. Excedrin gives pain relief. Objectively, that is a pleasant result. But what I read about marijuana is the opposite. The side effects seem to be minimal, but what is actually does, its main effect, as described in current scientific literature, is not positive. If there were a warning label (and I'm sure they're being developed, does anyone have a link?) it would have to say, "has a high risk of causing transient anxiety, panic, paranoia and psychosis. Long-term use may make some of these symptoms permanent" before the rest of the list. Exactly what benefit on healthy individuals does marijuana bestow that objectively outweighs those risks? Those sound like four of the five worst mental states I can think of (the fifth being severe depression).  Is there a rational way to ignore those risks, even if they're transient in the short term?

    Gerhard Adam
    Is there a rational way to ignore those risks, even if they're transient in the short term?
    The problem isn't the effect, but whether it is a basis of establishing a public policy.  There is nothing you can argue about marijuana/THC that isn't also applicable to alcohol, and even more so with many of the prescription drugs that are currently given [and abused].

    All risks are typically ignored by those individuals that wish to pursue a particular lifestyle choice.  Is it any different whether we're talking about guns, recreational pharmaceuticals or even cars/motorcycles?  What about rock-climbing, scuba-diving, sky-diving, bungee jumping, etc.?  How does a rational individual ignore these risks?

    We already have plenty of evidence regarding the effects of alcohol and cigarettes, yet they aren't banned.  So, I'm questioning whether it is legitimate to try and be "objective" regarding marijuana simply because that seems to be the political consensus.  Whose job is it to make life risk-free? 
    The side effects seem to be minimal, but what is actually does, its main effect, as described in current scientific literature, is not positive.
    The real problem occurs when this drug is held to a different standard than many higher risk drugs, especially when it comes to potentially therapeutic effects from cancer treatments, etc.  It appears that there may finally be some in-roads in this area.

    As a result, all things considered, marijuana is largely "harmless" to a much greater degree than many other already, legal choices. 
    ..."has a high risk of causing transient anxiety, panic, paranoia and psychosis. Long-term use may make some of these symptoms permanent"
    That could also be used to describe many people's jobs and/or commute to work.  :)

    Mundus vult decipi
    its main effect, as described in current scientific literature, is not positive.
    Given that people use it for the main effect, is this not all you need to know about what the scientific community's mechanisms select for?  Pot is one of the examples where we see that science (the actual social construct, not the "scientific method" that scientistic missionaries proselytize with) is not trustworthy with important issues like the war on drugs.  As a scientist who knows about how science works, I say: Stuff the scientific papers in the trash and try it!
    If there were a warning label (and I'm sure they're being developed, does anyone have a link?) it would have to say, "has a high risk of causing transient anxiety, panic, paranoia and psychosis.
    There's no evidence that the risk for those possible reactions is high.

    Objectively, that is a pleasant result. But what I read about marijuana is the opposite. The side effects seem to be minimal, but what is actually does, its main effect, as described in current scientific literature, is not positive.
    Interview 1000 pot users at random. Come back to me if you discover that the average intake does not make most of them experience pleasure instead of panic or psychosis. 

    I would say that these articles that you are bringing up seem to be geared toward finding negative effects in MJ. Just the abstracts seem like they are saying "MJ has been shown and should cause psychosis, so lets do a study that PROVES that it causes psychosis." Most scientific studies are biased anyways, because they want to please and are built to please the people financing the research institute. Who funds the most scientific research in any country, the country's government. If you want to talk about actual effects, you have to not only consider the perceptive effects of a substance, but also the non-perceptive. Ibuprofen causes pain relief because it literally thins out your blood. Too much of it can make you pass out, and less of it than you would think can kill you. MJ, on the other hand, basically regulates and heals your body. It recovers appetite, helps you sleep, relaxes the muscles, and more that is most likely in the studies somewhere. There is no mention as to the DEGREE of the perceptive symptoms either. When we hear paranoia, the first thing we think is mental hospital-grade paranoia. The reality is that it expands on whatever mindset we have at the time, and if you are worried you will get caught wherever you're using it then the worry will simply be expanded into a form of paranoia. "Worry", however, is not a very scientific word is it? Not to mention if I got extremely high at a research institute, being asked a bunch of questions and not having any kind of stimuli except doctors watching me, I'd be pretty paranoid too haha! The simply put fact is: anyone that would only use scientific studies to decide whether to use something is not as smart as he thinks he is. Nothing is done without a reason, especially expensive scientific studies. You have to explore ALL avenues and actual information from people who have done it. You wouldn't ask someone how fun a roller-coaster was if they haven't been on it would you? Ya, it causes nausea, disorientation, whiplash, headaches, but roller-coasters are a blast! My point is that scientific studies are a narrow view for a subject and decision that requires broader research.

    " And by the way, in response to your understandable accusation that I hand-picked the articles I presented to present a certain point of view,"

    I did not mean to imply this. I meant that we know in advance that any tiny, haphazardly chosen subset is going to be lacking when there are hundreds of primary research articles. Did you not find any recent review articles? But yes, searching randomly is exactly how people conduct these faux debates online (yes it is dangerous! look at this study! it's peer reviewed!)

    Of course the papers sound scary and negative. The way these studies are reported to the public is of course even worse. Even the (probably well-intentioned) scientists who do the studies have to play up the urgency for doing them to obtain grants, even though cannabis has been used relatively safely by hundreds of millions of people for thousands of years. Even the freaking drug czar of the US recently admitted that pot was less harmful than alcohol!

    But the NIDA funded researchers have to emphasize the possible dangers to get their grants and that sets the tone right in the abstract and title. Usually when you read the article it is a lot less impressive- eg some tiny effect in heavy users (five joints per day every day for decades) in some rare condition, and it turns out that other researchers have not even found the same effect, etc. They are all like this. It's a result of obsessively looking for harms in something as much as anything else IMO. Plus what Gerhard said:)

    "As a result, all things considered, marijuana is largely "harmless" to a much greater degree than many other already, legal choices. "

    yes, exactly it is held to a higher standard. WHY? And why does everyone just go along with this?? As I've said many times we are in an insane cycle. A new commission is formed, they look at the evidence, conclude prohibition should be repealed. Government ignores recommendations, everyone forgets about them and goes back to arguing if pot is harmful and should it be's time for a meta-analysis of the situation. Not just the moneyed interests- why do we go along with this, especially scientists and those in the health fields?

    By all means, feel free to post a reading list here of peer-reviewed articles that you think I should read. As I mentioned in another reply, I'm making a list of specific questions I would like to investigate to get more at my central question (the description of effect by users and the description of effect by observers of users). I'm sure I have lots of homework to do.

    A few points:

    First, whether something is legal, rational, or a good choice, are all different things. I'm sure marijuana will be legal eventually. But I'm not convinced that it is a rational or good choice for anyone (at least anyone healthy) to use it. My perception is that it seems to offer a worthless short term, artificial benefit with no real benefit (although I could say the same thing about most entertainment options) and real risks to mental health, which is the most important kind of health. And remember, tobacco was used by hundreds of millions of people for centuries, too, but no one realized how bad it was until the mid-twentieth century, when they started to ask the right questions. That recent data on THC and immune suppression caught my eye, and I would like to see more data to see if that holds any truth in humans, because its something I'd never considered before. I think the fact that the number of marijuana research papers has increased dramatically in the last few years is driven, in part, by the increasing public and political interest in it, but I think it also indicates that there are still a lot of research questions that need answering. 

    On that same point, alcohol is terrible for people, and we all know it. Alcohol and tobacco should not be the standard by which we judge whether a substance should be safe or benign, let alone legal. That's just my opinion. In my mind, that's like judging the security of a boat by saying, "hey, it's not as unsafe as the Titanic was!"

    Gerhard Adam
    Alcohol and tobacco should not be the standard by which we judge whether a substance should be safe or benign, let alone legal.
    I think this hits the crux of the problem.  These are two entirely separate questions.  What does legality have to do with "safe or benign"?  Moreover, since when is that a necessary condition for society/politicians to establish that an individual is to be criminalized?  No matter what conclusion one reaches about marijuana, does it really make sense that people should be imprisoned for its use or sale?  Is it truly so dangerous that there are official policies against growing hemp?  Is it so dangerous that we must spend billions of dollars in law enforcement to track down people and destroy plants?  Is that what the science says?

    Bear in mind, that this is a fundamental philosophical position that must be satisfied first, after which one can address whether or not cannabis represents some unique situation that should exempt it from such consideration.  So, if the criteria for legality is "safe or benign", who decides what meets that standard?   Even seemingly obvious arguments are seriously flawed [i.e. cannabis leads to lung cancer], because it presumes only one means of ingestion.  How does one get lung cancer if they eat it?  This is only one of the many flaws that permeate this type of discussion.

    Personally, I don't see how you can have such a criteria and not be more repressive and encounter more difficulties than leaving it open for individual choice.  While using the criteria you have is perfectly valid for personal decisions, it is problematic when applied to the broader social spectrum.  This is precisely why this isn't a scientific question.  Science provides information, it doesn't set policy.

    We don't need a lot of research papers to recognize that ANY recreational drug is going to be potentially harmful to the user.  It is a substance that modifies the body's chemistry and will always be more risky than leaving things alone.  This is especially true when one recognizes that all recreational drugs will affect the brain, so by what criteria do we allow some but not others?

    Research papers are useful in establishing whether there's any medicinal benefit to a particular drug, as well as highlighting what effects [positive or negative] such a drug might provide.  However, it tells us nothing about public policy or the law.

    To exclude the recreational aspects of it for a moment, consider this comment.
    Canada, New Zealand and several countries in Europe have approved the nasal spray Sativex, which uses purified cannabinoids derived from marijuana for the treatment of cancer pain and muscle spasms in multiple sclerosis. The U.S. Food and Drug Administration approved two drugs made from synthetic cannabinoids, dronabinol and nabilone, which treat nausea and appetite problems in cancer and HIV patients. Yet the FDA has not approved marijuana in its plant form as a treatment.
    This reeks of profiteering and seems like the scientific concerns are a bit flexible when there is a conventional profit to be made.

    As I said, the bias is plain when it has taken decades to seriously consider marijuana as a medicinal plant that is easy to obtain.  Instead, any serious scientific query has been stifled by political agendas governing recreational use. 

    In the end, I find the entire discussion surrounding marijuana far too biased to be useful and indicative simply of decades-old hype that is largely fantasy.  Is it good for you?  Probably not, but that doesn't make it inevitably harmful either.  In susceptible individuals almost any claim can be rationalized, but overall, much of the discussion is a faux concern.  This is precisely why many politicians are finally recognizing the need to decriminalize it. 

    As a personal decision, I think you're spot on.  As a societal policy, I think it's dead wrong.
    Mundus vult decipi
    Well, again, I agree with what you're saying, and obviously this is all part of a much larger policy discussion.

    But here's my hang-up. The only reason anyone's talking about legalizing marijuana is because so many people want to use it as a recreational drug, and the only reason that people want to use it as a recreational drug is because of the commonly held perception that it conveys some kind of positive feeling. But there seems to be a huge disconnect between that perception and the results described in what I've read so far, and I'm still trying to wrap my head around why. 

    I think what I really need is to go back and dig deep into the literature about the perceived positive effect of marijuana (specifically the THC compound) and the relative occurrence of a positive experience versus a negative experience. I would specifically be interested to know if the relative occurrence of a positive experience (tranquility, coolness of experience) vs a negative one (anxiety, panic, paranoia), and if the rate of negative experiences increases as the concentration of THC is selectively raised. I need to have a more clear understanding if these negative things are a "risk", a "high risk," or a "result" of marijuana use. I think that's where the policy driver really lies.

    By the way, it absolutely kills me that tobacco is so often used as the standard for legalization. If it were introduced today, there's no way it would ever be considered for legalization. It's arguably the worst consumer product ever, especially today. But obviously there are a lot of factors that determine a society's laws.

    Gerhard Adam
    By the way, it absolutely kills me that tobacco is so often used as the standard for legalization. If it were introduced today, there's no way it would ever be considered for legalization. It's arguably the worst consumer product ever, especially today.
    ... and therein lies the problem.  When did it become "society's right" to determine what individuals do in that respect?  I find it interesting that you target tobacco as the "worst consumer product ever", despite the fact that we have a major obesity problem in this country [the U.S.] which clearly indicates that there are other "dangerous" products out there.  While it is entirely appropriate to regulate behaviors that may be dangerous or destructive to others, it is questionable when society wishes to take on the responsibility of controlling individual behavior. 
    ...because of the commonly held perception that it conveys some kind of positive feeling.
    Whoa ... it's not a perception.  That's why people do it.  Especially given its legal status over the years, it would be absurd to argue that people don't enjoy it.  So, regardless of how many studies one wants to read, there is nothing that can ever be published that explains the subjective feeling an individual experiences.  It's as impossible as trying to explain why some people crave chocolate.

    I think you've identified part of the problem in your comment.  Subjective feelings are not "perceptions".  This is what individuals experience and it shouldn't be discounted by an attempt to be "objective" [which can never occur in any meaningful way].

    It's like an article that was recently posted titled to reflect that marijuana only reduced pain subjectively.  The title was ridiculous since all pain is subjective. 

    Mundus vult decipi
    With the tobacco comment, make no mistake, corn syrup is probably number two under tobacco. By opinion on tobacco being so bad isn't just because it causes cancer and emphyzema. The big three things that advertisers target  are health, beauty, and social appeal, and cigarettes make you very unhealthy, prematurely old, smelly, and, in our current society, a social outcast that no one wants visible in public places, and on top of all that, it's extremely addicting. It's a bad consumer product because, in theory, it should be impossible to advertise, and it shouldn't make any money. That's where my opinion comes from. If I were a tobacco company owner, I would be advocating hard for legal marijuana and trying to turn over all my fields for cannabis. 

    Returning to the point on perception, this is why this whole discussion is interesting to me. I have some clarifying points to make on this, but I want to read some more first. 

    and the only reason that people want to use it as a recreational drug is because of the commonly held perception that it conveys some kind of positive feeling
    What???  Look David, you need to stop and think harder about how the propaganda works on many levels at once.  As long as you refuse to look into why people take it and instead draw your conclusions around three corners, you effectively support the propaganda.  You have been suckered in, but there is a simple thing you can do.  Do it!  It belongs to higher education!  You are missing an important part of a rounded higher education, a tool that may be precisely what you need.  We talk about nootropics and mental enhancement, not "recreation" of lower workforce functionality as if it is 1800.
    The only reason anyone's talking about legalizing marijuana is because so many people want to use it as a recreational drug, and the only reason that people want to use it as a recreational drug is because of the commonly held perception that it conveys some kind of positive feeling.

    I'd suggest that most of the people who want it decriminalized, are or have been users, so it's not perception that it's pleasant, it's personal experience that shows it to be pleasant.
    A large majority of users find this to be true, while a small number who try it and go not enjoy it's effects, stop using it.
    Never is a long time.
    Apart from a few who find it unpleasant but continue to use it for other reasons - and not medical ones.

    I'm curious to know why you have never tried cannabis (the word "marijuana" is awkward, of racist origin, and just sounds silly to me especially since no actual user has ever used the term). You do bring up an interesting point, that getting high is seen as a negative, and discussion of positive effects is generally taboo. Even a casual account of enjoying use of cannabis is suspect. What was going on in the accounts you read? People were being examined by doctors? Would make anyone paranoid:)

    Not long ago someone wrote a humorously cheerful account of how his medical use for back pain has led to him enjoying hanging out with his kids more than he used to. The response in some of the science blogs (Drugmonkey, PalMD, Isis) was outrage; that you shouldn't be high when you are caring for children (yet they often joke about drinking while parenting) and he has all the signs of an addict in denial, and where was the indication in his essay that there could be harms? as if every mention of enjoying cannabis has to come with a list of side effects.

    As to why I've never tried it, I have a number of reasons. I'll list a few. I knew smart kids in school that changed for the worse while doing things that included smoking pot. I don't like the way people look or act when under the influence. It unsettles me. It doesn't pass the eye test of things I would feel safe doing. And I have a strong, strong gut reaction to things that mess with the brain. I found the descriptions of the locations of CB1 receptors and cell types to be very interesting and concerning. I used to be an epilepsy specialist, and I gained a healthy appreciation for the delicacy and fragility of the hippocampus and basal ganglia. I'd never want to mess with those systems on purpose, even a little bit, unless there was something already wrong with them and I needed a drug to correct it. I did some research recently into concussions, which were also not considered serious until a few years ago, and it has made me even more protective of my brain as I've realized that little digs over a wide brain surface area can have terrible, accumulating long-term consequences. Also, I hadn't considered it before yesterday, but the linkages between psychosis and the effects of cannabis are also not reassuring. I also know people with schizophrenia, and I wouldn't like to be in their shoes even for a minute. I'm a fiction writer by hobby, so I like having my head in the clouds in spurts, but I really like knowing that I can return to reality on my own time. 

    As to your comment "as if every mention of enjoying cannabis has to come with a list of side effects," well, yes it does, if there are some. That's the way our pharmacological culture is set up. We take sleep meds, and we sleep well, and we feel drowsy in the morning and need other substances to wake us up. We take a drug that frees us from depression and makes us able to be happy again, but it clouds thinking. It is good and healthy to acknowledge all aspects of an experience, because it allows us to deal rationally with the whole bag of consequences. In my mind, every positive cannabis experience should at least come with an asterisk. But again, I'm still trying to determine what exactly should be attached to the asterisk.

    The NYT opinion piece I referred to was a casually expressed opinion of a personal, subjective experience. So would you demand the same of references to alcohol - object to someone writing about enjoying the camaraderie of having beers with their friends or wine tasting in Napa valley or whatever? I have never heard people react with outrage when alcohol is casually discussed like this. How about an account of someone enjoying the thrills of sports, how they played on the football team- should these all come with disclaimers? You can't be serious. By the way, have you ever tried alcohol? I agree that you shouldn't try pot- you would definitely become paranoid.

    Yes, all drinking comes with an asterisk. And yes, watching sports which encourages participants to get concussions for your viewing pleasure comes with an asterisk, too. The leftover Christmas chocolate I ate last night comes with a big fat asterisk, and it was delicious. I like the idea of the asterisk because it forces you to consider all sides of an experience. Getting together for drinks with friends is fun, can lead to good experience, etc, but it also kills brain and liver cells, impairs judgement and increases the odds that you'll do or say something dumb in front of those friends. Do that enough times in a row and there are big consequences. Lots of experiences that we accept absolutely have subtle dark sides that we choose to ignore and that require acknowledgement. That's the key to rational decision making and a healthy, lucid perception of reality. Are all of the things I mentioned fine, legal and enjoyable things to do? Yes*.
    I probably went overboard with the Titanic comment (pun!). I got pretty tired of reading comments last night*. What I was trying to convey, (and they mention this in that 1972 "marihuana" commission report that I read to write Part II), was the gold standard for ethics is "Do no harm", not "Do harm, but not as much harm as that other thing". I'm very conflicted about the argument that we should accept something in society just because we already accept something way worse in society-- and that doesn't just apply to health.  I think the argument for decriminalizing cannabis because it has some medical potential in the right doses is a valid one. I think the argument that it should be decriminalized because its various detriments are not as bad as other detriments is not valid.

    And to answer your question, I tasted beer once. I thought it was gross. 

    "Yes, all drinking comes with an asterisk."

    Hmm, sorry, i am confused. You are joking I guess. I meant writers don't feel obliged to literally add these disclaimers to every piece they write. Oh well I don't want to beat a dead horse.

    " I'm very conflicted about the argument that we should accept something in society just because we already accept something way worse in society"

    we already accept it! It is the government that does not accept it. We are talking about ending prohibition, not legalizing something new. It is a human rights issue, all over the world. *especially* as each government has repeatedly concluded that the prohibition is not justified. The"argument" you refer to is a statement about the blatant hypocrisy. The US drug czar's recent excuse was that alcohol has a cultural history and should be grandfathered in. But cannabis has a deep relationship with humans also.

    I missed your titanic comment, but I was just reviewing those commission reports and was planning to suggest several of them to you! so I look forward to reading your post:)

    Gerhard Adam
    I'm very conflicted about the argument that we should accept something in society just because we already accept something way worse in society-- and that doesn't just apply to health.
    Of course it does, which is precisely why you have fast food restaurants on every corner instead of vegetable stands.  It isn't a question of telling people that something is good for them, it's a matter of whether such a disagreement warrants labeling them as criminals.  Those are the choices.

    Regardless of how much you may disagree with someone's views, I'm not prepared to criminalized their behavior.  Can you imagine if we applied the vegan standard of health to our criminal law?  What if it were illegal to now belong to a gym?  Should our citizens have to pass a fitness test every three months like in the military? 

    You seem to be hung up on the concept of "accepting" something as if that's tantamount to mandating its use.  I can readily accept alcohol despite the fact that I don't drink.  What possible difference does it make to me [other than driving, etc.].  Similarly if someone wants to be vegan, what possible difference does it make to me?  There are already plenty of illegal drug-abusers and still, it has no effect on me [except for the government costs, interventions, and the problem of criminalizing it].  The drug users themselves, don't affect me one bit by their drug use.

    We cannot legislate away people's ability to make bad choices.  That's the point of freedom and choice, is not just to require good outcomes, but to also allow people to make horrible choices for themselves.  That's what freedom means.

    Do we really want to pen ourselves up like cattle, so that someone external determines how we live simply in an effort to keep us from harming ourselves?
    Mundus vult decipi
    Forgot to mention the article people were outraged about was in the NYT opinion page.

    The effects of pot are situational. A relaxed environment enhances the experience. Even just worrying about the effects may make them worse! It's not for everyone; some people do dislike the effects. If you do try it I recommend you be somewhere pleasant, outdoors, not under glaring lights in a medical establishment so you can record the effects:)

    " I need to have a more clear understanding if these negative things are a "risk", a "high risk," or a "result" of marijuana use. I think that's where the policy driver really lies."

    You mean these negative states? Again, as it is incredibly popular, common sense would indicate that most people are enjoying themselves most of the time....

    Uh,Dave's not here, man.....

    Actually a great article.  Science nerd stream of consciousness! 
    Steve Savage
    John Hasenkam
    I have seen people take one or two hits of pot and curl up into a corner. Then there are people like me who could smoke all day, read some interesting books and a few research articles, go out for a walk(seriously - walking while stoned with headphones for music is wonderful for me), then go out and spend sometime with the straights who don't know I'm stoned. 

    When I started smoking so long ago I noted how many potheads had scattered working memory and poor concentration. So I would play this little game with them: I'd watch the conversation drift, and by golly do potheads know how to conceptually drift, and then drag the conversation back to its starting point some minutes earlier. The stunned looks, the struggling to find the relevant cues and typically failing. An old friend of mine, very smart, sat for a State wide entrance test for public servants while completely stoned and topped the State! There are some people who manage a specific drug better than the general popn. So I am very wary about statistical studies when individual responses to drugs can be so varied. In regard to testing contexts, these are anxiety laden events, pot and anxiety contexts are a very bad mix so the results are not necessarily indicative of the real world effects. On the basis of statistical studies, to make the claim that pot is bad for everyone, is illogical. However, if you have anxiety issues pot can produce very unpleasant effects.   

    In those earlier years the pot worked for me but I am a freak, a person with multiple medical issues including possible minor orbitofrontal damage and some chronic pain issues. Now it does not work for me except for relaxation, listening to music, and, somewhat paradoxically, when I am working on a difficult issue, it slows me down so much I think very carefully. Pot can be terrible for intellectual work. If it does help it is when as an old friend of mine told me that he knew a physicist and a mathematician who when stuck on a problem would get stoned. 

    In regard to psychosis the debate still rages as to whether it is in those so predisposed or is an independent causal agent. From what I've seen most bods lean to the former view. If pot were such a serious psychosis problem it should be reflected in varying rates of psychosis across populations. I think the risk for under 21 years of age is real but small, as one British study found: you would have to stop several thousand people smoking to prevent one occurrence of psychosis. If we adopt that as a reasonable safety standard then we can never leave our houses, drive our cars, go on the internet ... . The big problem though is that modern strains have a much higher THC\CBD ratio and that is a worry, let alone the recent emergence of THC analogues onto the streets. 

    The single biggest problem with pot is not psychosis but rather it slows you down too much for some types of work. This can be overcome but only with good planning and even then the results are generally limited. When I started smoking I observed effects in others and developed strategies to prevent that happening, like forcing myself to maintain concentration no matter how stoned, though often there is no "forcing" involved, I could just sink into this deep concentration mode and I loved that.

     In my experience most regular pot smokers are "failed rebels": people who think society is stuffed up and want out. There is no point "kicking against the pricks" when you keep coming away bloodied and bruised. So they stay home, get stoned, and forget about the world. That is an adaptive strategy and not necessarily a bad one. Give them a break, brilliant people have come to the same conclusion and left society. There is an old Harvard study that addresses this: they wanted to know why some of their graduates had "vanished" so they tracked them down. Turns out these graduates had bailed out of society, wanted no part of it. There was nothing psychologically wrong with them, they just had different values that clashed with the prevailing norms. Unfortunately both psychiatry and psychology seem to demand that if you don't fit into society at large than by default something must be wrong with you. 

    Stoned or straight the literature on marijuana is confusing and confounding. Jimmy's big mistake was to believe that he could know how good or bad something is for him based on the averaging of results on studies of thousands of people.The big rage today is about person specific medical intervention. How about person specific drug use? Humans are not homogeneous entities. 

    Gerhard Adam
    The single biggest problem with pot is not psychosis but rather it slows you down too much for some types of work.
    To reiterate, this isn't just a problem with pot.  That's why even cough medicines may warn against operating machinery.  I think we can all agree that activities always need to be considered against any drug that is used, but that wouldn't be much of a criteria in determining legality.

    I also agree with you regarding the varied effects that marijuana can have on different individuals, so drawing specific conclusions is too nebulous to provide practical advice.
    Mundus vult decipi
    Now even you start to be suckered in.  That it "slows you down" in a certain way is precisely why teenagers drive more safely when stoned!  Actually, it does not "slow down" so much as to shift the focus onto the more relevant.  It also slows people down answering.  Of course, because it makes people actually consider the question for a change! 
    Yes, for me it does enhance insight and creativity for this reason. I think this is where the paranoia comes in, at least based on my occasional experience with this unwelcome effect. Layers of self deception may be stripped away faster than someone is prepared to deal with. As far as the common accusation that "you just think you are more creative"; I tested this in art school. I took an illustration class that was basically an open, loosely defined weekly assignment and subsequent class critique of our individual efforts. I tracked the response to my work, and the assignments I did under the influence were indeed viewed as superior and more creative.

    Pot plus modafinil...
    Gerhard Adam
    While not directly related to your original point, it is worth considering this article.

    Here is a clear example of a great deal of scientific information, legal controls, and yet we find that people will still pursue their "recreation" however they choose.  Yet, despite these bad choices, I would fail to see how making these individuals criminals would solve any problem.
    Mundus vult decipi
    With over 20,000 scientific studies, marijuana is probably the most studied plant on this planet. As pointed out earlier NIDA has severely limited the scope of the studies to fit the "drug of abuse" category that plays into a catch 22 game where it is illegal to study unless the study conforms to the drug of abuse scheme.

    We are all drug users in this society, Every one of us; coffee, chocolate, sugar, alcohol, you name the food and it has a drug component to it..
    Foods as Drugs Drugs can be beneficial, if not abused. Marijuana like substances are flowing around your body. Mothers breast milk contains these cannabinoids, to regulate the baby's health.

    Cannabis is considered by some experts to have a significant level of safety, by any standard of measurement.

    It is true, that they do not teach doctors or scientist much in the way of the bodies our endocannabiniod systems. Most doctors are also not schooled in nutrition, so that should tell you where our science and health institutions are aims are.

    From my perspective, I have seen and witnessed the healing powers of cannabis. I can hear it in their testimonies, and their are lots of them. If something works, has a history of working, and can be made as cheap as a few seeds .... this is what people want. The drug companies will differ and persuade you and other doctors otherwise.

    I use cannabis as a religious sacrament, but yet let's not complicate your scenario with people who find religious practices enhanced by such entheogens like cannabis sativa.