Re: [tips] Cannabis damages young brains
���I think I blundered in my statistical calculation in my last posting on this thread. I wrote: Here are the statistics: http://tinyurl.com/yjeq7hm The risk was most increased for breast cancer. In developed countries like the UK, the chance of having had breast cancer by the age of 75 is 9.5 in 100. According to the study, for every extra daily unit of alcohol (over 2 a week), that risk increases by 1.1 per 100. So if you had a roughly 9.5 percent chance of getting breast cancer by the age of 75, but you drank one glass of wine a day, that risk would go up to 10.6 percent. If you drank two glasses of wine a day, that would increase to 11.7 percent. My calculation gives: Chance of getting breast cancer up to age 75 is approximately 1 in 10 Moderate drinking gives 1% increase, i.e., 1% of 10% = 0.1% increase = 1 in 1000 I should have argued that (using the figures from the study) that 9.5 women in every 100 get breast cancer by the age of 75. According to the study, for moderate drinkers this goes up to 10.6 women in every 100. That makes an increase of 1.1 women in every 100, i.e., an increase of roughly 1 in 100. This tallies with the conclusion at the end of the Abstract to the study: Low to moderate alcohol consumption in women increases the risk of certain cancers. For every additional drink regularly consumed per day, the increase in incidence up to age 75 years per 1000 for women in developed countries is estimated to be about 11 for breast cancer… http://tinyurl.com/yc6esev Chris Green wrote: when in fact the actual increase in the breast cancer rate was something like 2 in 10,000 By my reckoning that means Chris is out by a factor of 50. A reminder: The issue here is not the absolute validity of the study, but Chris's assertion: Without actually going back a checking press releases, I can recall the case of the moderate drinking causes breast cancer announcement in Britain earlier this year, in which it seemed pretty clear that the scientists had sexed it up for the university press team, who had then re-sexed it up for the new media, who had then re-re-sexed it up for public (when in fact the actual increase in the breast cancer rate was something like 2 in 10,000… As I wrote in my last posting, from the Abstract of the published study, the press release on a BMJ website (reprinted in the Guardian), and British newspaper reports of the study I can find nothing to support any of the above contentions. Allen Esterson Former lecturer, Science Department Southwark College, London http://www.esterson.org Re: [tips] Cannabis damages young brains Allen Esterson Tue, 29 Dec 2009 06:55:13 -0800 On 28 Dec 2009 Chris Green wrote: There's nothing surprisingly egregious about this particular article, is there? In response to which Stephen Black replied: I've never seen a university press release, which should have been vetted by the authors and presumably ran with their approval, hide the fact that the research was in animals. Chris Green responded: I'm still surprised. Without actually going back a checking press releases, I can recall the case of the moderate drinking causes breast cancer announcement in Britain earlier this year, in which it seemed pretty clear that the scientists had sexed it up for the university press team, who had then re-sexed it up for the new media, who had then re-re-sexed it up for public (when in fact the actual increase in the breast cancer rate was something like 2 in 10,000, and there was little reason to believe that alcohol, rather than the billion or so things correlated with increased alcohol consumption, was responsible even for this tiny increase). Let's all agree that there is much dismal reporting of scientific findings (especially in the field of health) in the media. But Chris's response to Stephen does not directly answer his challenge. Moreover his supposedly just as bad example turns out, on investigation, not to live up to Chris's assertions (at least as far as the British press is concerned). I though it might be interesting to investigate the specific example Chris gives concerning the study which was reported as saying that moderate drinking increases the risk of (not causes) breast cancer. My conclusion, at least in relation to the British press, is that the reporting was nowhere near as bad as Chris asserts, and that he understates the claimed increase of breast cancer rate for moderate drinking by a factor of about 5. First the study by the University of Oxford's Cancer Epidemiology Unit: Moderate Alcohol Intake and Cancer Incidence in Women, Allen N. E. et al, : Journal of the National Cancer Institute, Volume 101, Number 5, 4 March 2009 , pp. 296-305(10). From the Abstract's Conclusion (relating to alcohol): Low to moderate alcohol consumption in women increases the risk of certain cancers. For every additional drink regularly consumed per day, the increase
Re: [tips] Cannabis damages young brains
Regarding the alcohol-breast cancer finding: this is what I actually wrote back on 25 Feb: For instance, the [BBC] article [sensationally entitled Drink a day increases cancer risk] says that 5,000 of the 45,000 annual cases of breast cancer are due to alcohol -- an increase of 11% they say. The population of the UK is about 60 million. Half of the those are female -- 30 million. About 20% of those are children -- leaving 24 million. (see http://www.statistics.gov.uk/cci/nugget.asp?ID=6). 45,000 out of 24 million = .0019: 19 in ten thousand women are diagnosed with breast cancer in any given year. Even if the alcohol-cancer causal link were, in fact true, the number of cancer cases would drop to 40,000 which, against a vulnerable population of 24 million is .0017: 17 in ten thousand. Now ask yourself the question: Would you change you lifestyle dramatically to reduce a risk by 2 in 10,000? And that's if the causal link had been established, which it hasn't been. Regards, Chris -- Christopher D. Green Department of Psychology York University Toronto, ON M3J 1P3 Canada 416-736-2100 ex. 66164 chri...@yorku.ca http://www.yorku.ca/christo/ == --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
Re: [tips] Cannabis damages young brains
I think I would be better advised to keep clear of this particular dust-up (on breast cancer risk and alcohol intake) even if it was my post (on cannabis!) which seems to have ignited it. Yet I'm intrigued by the discrepancy in the statistics quoted by Chris and Allen. So while Allen sleeps, which is presumably what they do in England at this time of night... Chris says: Would you change your lifestyle dramatically to reduce a risk by 2 in 10,000. Allen instead calculates a reduction in risk of 1 in 100. I think I see the problem. Chris is using annual statistics, i.e. cases in a single year. Allen is using lifetime statistics, up to age 75. I think the decision to change one's lifestyle is best made on the basis of lifetime risk, hence Allen's statistics apply. In my opinion, a reduction in the lifetime risk of breast cancer of 1 in 100 is not trivial, although its personal significance would depend on how dearly you love alcohol. Of course, as has been noted, it would also require that the relationship between breast cancer and drinking be causal, which has not been shown. But I'm also intrigued by the note Chris reminded us he posted on February 25th, the one where he deplores the sensationalism of a BBC article on breast cancer risk and alcohol intake. Recently, he laid into me for my own complaint against a press release (the teenage brain and cannabis one), his point being that as it's all BS anyway, why bother mentioning it. I did find this dismissive and perhaps even a teensy bit condescending. So I'm pleased to discover that he doesn't always think that identifying BS in science is not worth doing. Me, I think it's always worth doing. Stephen - Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: sbl...@ubishops.ca 2600 College St. Sherbrooke QC J1M 1Z7 Canada --- --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
Re: [tips] Cannabis damages young brains
���On the subject of the reporting of scientific news in the media, Chris Green wrote [snip]: The news is a commercial product. Commercial products are routinely adjusted to ensure that they sell to the greatest number of people at the highest price (or rather, those that are not so adjusted, quickly cease to be commercial products). Surely it became clear to you long ago that journalists are not scientists (as if no scientist ever turned a phrase in order to make his or her work seem more exciting to the public), and certainly no journalist's boss is a scientist. Their values lie in a different place. In reply to which Stephen Black replied, quoting Chris first: Surely it became clear to you long ago that journalists are not scientists Some are both. Not all are shameless hacks intent on sensationalism. Some write excellent and intellectually honest accounts. As you note, there are good science journalists. I agree with Stephen that the world of the media, and journalists themselves, are just a wee bit more complex than Chris would have it. And I think it is important to distinguish between reports on matters in which science figures by non-science journalists, and those written by science correspondents. (A casual check on Ben Goldacre's Bad Science blog reveals that many of the articles that he rightly castigates are not written by science correspondents.) Writing from this side of the pond, I can assure you that there *are* intellectually honest science journalists, for example Mark Henderson of the London Times and Robert Matthews, former science correspondent of the Sunday Telegraph and now freelance. To suggest that such journalists are little more than newspaper hacks is simply untrue. I see that even poor old Ben Goldacre of Bad Science fame can't escape Chris's castigation: But what he has done is figure out a way to make good science journalism sexy: he badmouths other journalists (and scientists) who do exactly what they are paid to do (viz., make science salable to newspaper readers). It's good old gotcha journalism. As Chris is evidently unable to credit anyone in the media business with any integrity he represents (or misrepresents) even the invaluable work that Goldacre does in terms of hack journalism – he's found a way of making even good journalism sexy. Not that I think that Ben Goldacre escapes criticism completely (who does?), though in this instance it is in relation to his blog rather than to his published Guardian column. I note that among the topics listed on his blog he has a section headed Media containing links to his blog articles. This includes several British national newspapers, but missing are The Guardian and the Guardian-owned Sunday paper The Observer. Now this can't be because no doubtful scientific stories have been run by these newspapers, because a quick search reveals that Goldacre himself had written on at least a couple of Observer articles on his blog (with at least one that he published in the Guardian, about a major autism/MMR scare story in the Observer) – not to mention an Observer article as recent as 20 September this year that warned that health officials will not be able to stem the growth of the worldwide H1N1 pandemic in developing countries. If the virus takes hold in the poorest nations, millions could die and the economies of fragile countries could be destroyed. Incidentally, this latter story is of interest in that (a) it was not written by a science correspondent, and (b) it could not really have been said to have been sensationalised by the journalist, as he was simply basing his story on a UN report (though one would hope that a responsible science journalist would have treated the report with a modicum of scepticism). This illustrates that there are numerous complexities in the reporting of science in the media, ranging from the extreme position taken by Chris, to the more nuanced position of Stephen's. Allen Esterson Former lecturer, Science Department Southwark College, London http://www.esterson.org -- Re: [tips] Cannabis damages young brains sblack Sun, 27 Dec 2009 20:30:07 -0800 I said, deploring a news article on the dangers of pot for teenage brains from a report which failed to mention that the research was on rats: Why they did it is obvious. Studies demonstrating the dangers of cannabis for teenagers are sexy; such studies for rats, not so much. If you want publicity, you go with what is sexy, and hide what can impair it. It's also wrong. Chris Green replied: What is it that surprises you about this Stephen? Nothing. As I said, why they did is obvious. I was deploring it. Surely it became clear to you long ago that journalists are not scientists Some are both. Not all are shameless hacks intent on sensationalism. Some write excellent and intellectually honest accounts. As you note, there are good
Re: [tips] Cannabis damages young brains
sbl...@ubishops.ca wrote: There's nothing surprisingly egregious about this particular article, is there? Yes. I've never seen a university press release, which should have been vetted by the authors and presumably ran with their approval, hide the fact that the research was in animals. I'm still surprised. Without actually going back a checking press releases, I can recall the case of the moderate drinking causes breast cancer announcement in Britain earlier this year, in which it seemed pretty clear that the scientists had sexed it up for the university press team, who had then re-sexed it up for the new media, who had then re-re-sexed it up for public (when in fact the actual increase in the breast cancer rate was something like 2 in 10,000, and there was little reason to believe that alcohol, rather than the billion or so things correlated with increased alcohol consumption, was responsible even for this tiny increase). Sorry to be so blase about the whole thing, but far from being unusual, it is endemic Chris -- Christopher D. Green Department of Psychology York University Toronto, ON M3J 1P3 Canada 416-736-2100 ex. 66164 chri...@yorku.ca http://www.yorku.ca/christo/ == --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
Re: [tips] Cannabis damages young brains
I said: Read this news report. Then answer a simple question: who were the subjects of this alarming study? - Cannabis Damages Young Brains More Than Originally Thought, Study Finds On 24 Dec 2009 at 13:47, Gerald Peterson wrote: Is the objection to the sweeping generalities in the piece? Is it to the emotionalism in the news notice? snip Is it that a rat model is not appropriate to answer questions about cannabis effects? Is the rat model not at all relevant to human teen brains? It seems that my outrage has been met with puzzlement. I wasn't disputing the importance of animal research, or its relevance for understanding the human brain. I fully support animal research for advancing neuroscience. What I do not support is omitting essential information from a press release and from news article based on that release. The significant information was the word rat. It seems to me there was likely a deliberate attempt to prevent the reader from learning that the study was carried out in rats, and instead to encourage the conclusion that humans were studied. This was done by using terms such as adolescent, teens, and even Canadian teenagers, all of which (unless some rats have taken to wearing baggy pants, dissing their parents, and listening to hip-hop) invariably makes us think of not-fully-grown humans. I never heard a rat called a teenager before this study, Canadian or not. Why they did it is obvious. Studies demonstrating the dangers of cannabis for teenagers are sexy; such studies for rats, not so much. If you want publicity, you go with what is sexy, and hide what can impair it. It's also wrong. Rat studies are important. But it's a truism that rats are not people, and we cannot simply assert their interchangeability, at least not without further evidence. At a minimum, I would have expected responsible researchers to say something like this, While this study was carried out in rats, future research may lead to the discovery of similar brain changes in teenagers. But if they did that, everyone, including journalists, would say ho-hum. Because we've had more than a few generations of dire warnings about the toxic and brain-damaging properties of pot, none of which have been supported by credible evidence. One more rat study wouldn't do it for most people. Moreover, if these researchers were so determined to show that cannabis is harmful to humans, why weren't they studying humans in the first place? Yes, we have to use rats to study changes in neurochemicals in the brain, because teenagers won't lend us their brains for the purpose. But the neurochemical changes--- depression hypothesis is in trouble, and jumping from neurochemical changes in the rat brain to human depression is a leap as great as the best of Evel Knievel's. Note that the behavioural measures in this study were such things as forced swim and sucrose preference for depression, and novelty-suppressed feeding test for anxiety. When was the last time we diagnosed depression and anxiety in teenagers with those kind of tests? OK, rant ends. I repeat the offending news report below so you can compare it with the above. As you read it, remember, they're really talking about rats for their findings. Stephen ScienceDaily (Dec. 20, 2009) - Canadian teenagers are among the largest consumers of cannabis worldwide. The damaging effects of this illicit drug on young brains are worse than originally thought, according to new research by Dr. Gabriella Gobbi, a psychiatric researcher from the Research Institute of the McGill University Health Centre. The new study, published in Neurobiology of Disease, suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain. We wanted to know what happens in the brains of teenagers when they use cannabis and whether they are more susceptible to its neurological effects than adults, explained Dr. Gobbi, who is also a professor at McGill University. Her study points to an apparent action of cannabis on two important compounds in the brain -- serotonin and norepinephrine -- which are involved in the regulation of neurological functions such as mood control and anxiety. Teenagers who are exposed to cannabis have decreased serotonin transmission, which leads to mood disorders, as well as increased norepinephrine transmission, which leads to greater long-term susceptibility to stress, Dr. Gobbi stated. Previous epidemiological studies have shown how cannabis consumption can affect behaviour in some teenagers. Our study is one of the first to focus on the neurobiological mechanisms at the root of this influence of cannabis on depression and anxiety in adolescents, confirmed Dr. Gobbi. It is also the first study to demonstrate that cannabis consumption causes more serious damage during adolescence than
Re: [tips] Cannabis damages young brains
sbl...@ubishops.ca wrote: I never heard a rat called a teenager before this study, Canadian or not. A teenage rat would be extremely elderly! Why they did it is obvious. Studies demonstrating the dangers of cannabis for teenagers are sexy; such studies for rats, not so much. If you want publicity, you go with what is sexy, and hide what can impair it. It's also wrong. What is it that surprises you about this Stephen? The news is a commercial product. Commercial products are routinely adjusted to ensure that they sell to the greatest number of people at the highest price (or rather, those that are not so adjusted, quickly cease to be commercial products). Surely it became clear to you long ago that journalists are not scientists (as if no scientist ever turned a phrase in order to make his or her work seem more exciting to the public), and certainly no journalist's boss is a scientist. Their values lie in a different place. There are, to be sure, some good science journalists. Ben Goldacre of the Guardian comes to mind. But what he has done is figure out a way to make good science journalism sexy: he badmouths other journalists (and scientists) who do exactly what they are paid to do (viz., make science salable to newspaper readers). It's good old gotcha journalism. It is, of course, worth pointing out that the the pot-hurts-brains article was BS, but being outraged seems a bit, well, disingenuous. Almost all reporting on illegal drugs in the mainstream media is BS, and has been since the 1960s -- from pot-is-addictive, to LSD-causes-genetic-damage, to crack-babies, to the suburban-crystal-meth-epidemic. It's all BS. There's nothing surprisingly egregious about this particular article, is there? Chris -- Christopher D. Green Department of Psychology York University Toronto, ON M3J 1P3 Canada 416-736-2100 ex. 66164 chri...@yorku.ca http://www.yorku.ca/christo/ == --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
Re: [tips] Cannabis damages young brains
I said, deploring a news article on the dangers of pot for teenage brains from a report which failed to mention that the research was on rats: Why they did it is obvious. Studies demonstrating the dangers of cannabis for teenagers are sexy; such studies for rats, not so much. If you want publicity, you go with what is sexy, and hide what can impair it. It's also wrong. Chris Green replied: What is it that surprises you about this Stephen? Nothing. As I said, why they did is obvious. I was deploring it. Surely it became clear to you long ago that journalists are not scientists Some are both. Not all are shameless hacks intent on sensationalism. Some write excellent and intellectually honest accounts. As you note, there are good science journalists. What I was bemoaning was not that a journalist tried to foist this crap on us, but that it came straight from the press release of the McGill University Public Relations and Communication Office. Here's what I said: It's not the fault of the science daily journalist, though, because this egregious misinformation is present in the original press release from McGill University. Shame, McGill! http://muhc.ca/newsroom/news/cannabis-and-adolescence- dangerous-cocktail or http://tinyurl.com/yhyedn5 Interestingly, I just checked the news report on this as it appeared in our major local paper, the Montreal Gazette, and I see that the reporter showed some initiative in restoring the missing information about it being a rat study (at http://tinyurl.com/yjzh4uh). The reporter also elicited this gem from the senior investigator, Although the research was carried out on laboratory rats, Gobbi said, one can assume the same effects on the human brain. Did she say that with a straight face? I liked some of the comments, particularly this one from Logic Barbeque: Just because marijuana is a plant doesn't mean it's harmless.' What, really? And here I thought poisonous mushrooms couldn't hurt you. Gazette: your headline should read Toking teen rats risk brain damage. Please correct it. Thanks! And this one, from ER Doctor: This research was done in rats with WIN55,212-2, a very powerful synthetic full cannabinoid agonist. It cannot be cavalierly extrapolated to say anything concrete about adolescent human use of cannabis, a weak partial cannabinoid agonist agent. There's nothing surprisingly egregious about this particular article, is there? Yes. I've never seen a university press release, which should have been vetted by the authors and presumably ran with their approval, hide the fact that the research was in animals. That's disturbing, and well worth fulminating over. Or maybe I'm just excitable. Stephen - Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: sbl...@ubishops.ca 2600 College St. Sherbrooke QC J1M 1Z7 Canada --- --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
RE: [tips] Cannabis damages young brains
On first blush, without reading the original research, this seems to be a reporter overstating the findings of the study. The quotes of the author of the study do not appear to be as oriented to 'damage' (which implies something permanent or structural). It seems to me the author of the news report is the one who describes these effects as alarming 'brain damage.' Paul C. Bernhardt Department of Psychology Frostburg State University Frostburg, Maryland -Original Message- From: sbl...@ubishops.ca [mailto:sbl...@ubishops.ca] Sent: Thu 12/24/2009 1:43 AM To: Teaching in the Psychological Sciences (TIPS) Subject: [tips] Cannabis damages young brains Read this news report. Then answer a simple question: who were the subjects of this alarming study? - Cannabis Damages Young Brains More Than Originally Thought, Study Finds ScienceDaily (Dec. 20, 2009) - Canadian teenagers are among the largest consumers of cannabis worldwide. The damaging effects of this illicit drug on young brains are worse than originally thought, according to new research by Dr. Gabriella Gobbi, a psychiatric researcher from the Research Institute of the McGill University Health Centre. The new study, published in Neurobiology of Disease, suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain. We wanted to know what happens in the brains of teenagers when they use cannabis and whether they are more susceptible to its neurological effects than adults, explained Dr. Gobbi, who is also a professor at McGill University. Her study points to an apparent action of cannabis on two important compounds in the brain -- serotonin and norepinephrine -- which are involved in the regulation of neurological functions such as mood control and anxiety. Teenagers who are exposed to cannabis have decreased serotonin transmission, which leads to mood disorders, as well as increased norepinephrine transmission, which leads to greater long-term susceptibility to stress, Dr. Gobbi stated. Previous epidemiological studies have shown how cannabis consumption can affect behaviour in some teenagers. Our study is one of the first to focus on the neurobiological mechanisms at the root of this influence of cannabis on depression and anxiety in adolescents, confirmed Dr. Gobbi. It is also the first study to demonstrate that cannabis consumption causes more serious damage during adolescence than adulthood. http://www.sciencedaily.com/releases/2009/12/091217115834.h tm or http://tinyurl.com/yc99kal The answer is: They studied rats, teenage rats. See for yourself. Abstract of the published study at http://tinyurl.com/ygrcbye It's not the fault of the science daily journalist, though, because this egregious misinformation is present in the original press release from McGill University. Shame, McGill! http://muhc.ca/newsroom/news/cannabis-and-adolescence- dangerous-cocktail or http://tinyurl.com/yhyedn5 Stephen - Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: sbl...@ubishops.ca 2600 College St. Sherbrooke QC J1M 1Z7 Canada --- --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu) --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)winmail.dat
RE: [tips] Cannabis damages young brains
What a fantastic example for research methods class! From: sbl...@ubishops.ca [sbl...@ubishops.ca] Sent: Thursday, December 24, 2009 1:43 AM To: Teaching in the Psychological Sciences (TIPS) Subject: [tips] Cannabis damages young brains Read this news report. Then answer a simple question: who were the subjects of this alarming study? - Cannabis Damages Young Brains More Than Originally Thought, Study Finds ScienceDaily (Dec. 20, 2009) - Canadian teenagers are among the largest consumers of cannabis worldwide. The damaging effects of this illicit drug on young brains are worse than originally thought, according to new research by Dr. Gabriella Gobbi, a psychiatric researcher from the Research Institute of the McGill University Health Centre. The new study, published in Neurobiology of Disease, suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain. We wanted to know what happens in the brains of teenagers when they use cannabis and whether they are more susceptible to its neurological effects than adults, explained Dr. Gobbi, who is also a professor at McGill University. Her study points to an apparent action of cannabis on two important compounds in the brain -- serotonin and norepinephrine -- which are involved in the regulation of neurological functions such as mood control and anxiety. Teenagers who are exposed to cannabis have decreased serotonin transmission, which leads to mood disorders, as well as increased norepinephrine transmission, which leads to greater long-term susceptibility to stress, Dr. Gobbi stated. Previous epidemiological studies have shown how cannabis consumption can affect behaviour in some teenagers. Our study is one of the first to focus on the neurobiological mechanisms at the root of this influence of cannabis on depression and anxiety in adolescents, confirmed Dr. Gobbi. It is also the first study to demonstrate that cannabis consumption causes more serious damage during adolescence than adulthood. http://www.sciencedaily.com/releases/2009/12/091217115834.h tm or http://tinyurl.com/yc99kal The answer is: They studied rats, teenage rats. See for yourself. Abstract of the published study at http://tinyurl.com/ygrcbye It's not the fault of the science daily journalist, though, because this egregious misinformation is present in the original press release from McGill University. Shame, McGill! http://muhc.ca/newsroom/news/cannabis-and-adolescence- dangerous-cocktail or http://tinyurl.com/yhyedn5 Stephen - Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: sbl...@ubishops.ca 2600 College St. Sherbrooke QC J1M 1Z7 Canada --- --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu) --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
Re: [tips] Cannabis damages young brains
Is the objection to the sweeping generalities in the piece? Is it to the emotionalism in the news notice? Is it the author's over-generalizations that are the central problems? The over-stating and over-generalization---problems of external validity? Is it that a rat model is not appropriate to answer questions about cannabis effects? Is the rat model not at all relevant to human teen brains? In many instances rat models have been valuable in psych eh? What is the relevance or point that we might make in our research methods class here? My students would expect the problem is just that a representative sample of the brains of human teens were not studied. Is that really the problem here? Gary Gerald L. (Gary) Peterson, Ph.D. Professor, Department of Psychology Saginaw Valley State University University Center, MI 48710 989-964-4491 peter...@svsu.edu - Original Message - From: sbl...@ubishops.ca To: Teaching in the Psychological Sciences (TIPS) tips@acsun.frostburg.edu Sent: Thursday, December 24, 2009 1:43:09 AM GMT -05:00 US/Canada Eastern Subject: [tips] Cannabis damages young brains Read this news report. Then answer a simple question: who were the subjects of this alarming study? - Cannabis Damages Young Brains More Than Originally Thought, Study Finds ScienceDaily (Dec. 20, 2009) - Canadian teenagers are among the largest consumers of cannabis worldwide. The damaging effects of this illicit drug on young brains are worse than originally thought, according to new research by Dr. Gabriella Gobbi, a psychiatric researcher from the Research Institute of the McGill University Health Centre. The new study, published in Neurobiology of Disease, suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain. We wanted to know what happens in the brains of teenagers when they use cannabis and whether they are more susceptible to its neurological effects than adults, explained Dr. Gobbi, who is also a professor at McGill University. Her study points to an apparent action of cannabis on two important compounds in the brain -- serotonin and norepinephrine -- which are involved in the regulation of neurological functions such as mood control and anxiety. Teenagers who are exposed to cannabis have decreased serotonin transmission, which leads to mood disorders, as well as increased norepinephrine transmission, which leads to greater long-term susceptibility to stress, Dr. Gobbi stated. Previous epidemiological studies have shown how cannabis consumption can affect behaviour in some teenagers. Our study is one of the first to focus on the neurobiological mechanisms at the root of this influence of cannabis on depression and anxiety in adolescents, confirmed Dr. Gobbi. It is also the first study to demonstrate that cannabis consumption causes more serious damage during adolescence than adulthood. http://www.sciencedaily.com/releases/2009/12/091217115834.h tm or http://tinyurl.com/yc99kal The answer is: They studied rats, teenage rats. See for yourself. Abstract of the published study at http://tinyurl.com/ygrcbye It's not the fault of the science daily journalist, though, because this egregious misinformation is present in the original press release from McGill University. Shame, McGill! http://muhc.ca/newsroom/news/cannabis-and-adolescence- dangerous-cocktail or http://tinyurl.com/yhyedn5 Stephen - Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: sbl...@ubishops.ca 2600 College St. Sherbrooke QC J1M 1Z7 Canada --- --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu) --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
