The Smoking Gun? Not Exactly

A recent preliminary study from earlier this year by Catherine Orr et al. seems to be stirring the pot, so to speak.  Adding fuel to the already volatile tinderbox of moral panic around teen cannabis use, this study using brain scans appears to find brain changes in 14 year olds who have used cannabis only once or twice, compared with those who have never used it.  Specifically, those who had used it once or twice showed increased gray matter in various brain regions relative to those who did not, which, counterintuitively, suggests a disruption of the normal "pruning" process that occurs during adolescence (or something).  And of course, the MSM predictably just took it and ran with it.

Of course, correlation is not the same as causation, and there are still reasons to be skeptical of the findings and practical significance:

• The sample size was small:  46 people in each group.  Thus, very sensitive to potential selection bias, reporting bias, and confounding.  (Apparently from a larger brain study of over 2000 people, they could only find 47 individuals who had only tried cannabis once or twice by that age, and one had an inconclusive scan.)
• Another way that size matters is "effect size".  And while the numbers are difficult to interpret, they are also on the small side.
• Some underreporting of cannabis (and other substance) use is always very likely, and can skew results in either direction depending on what is being underreported and by whom.
• Temporality of the initial findings remains unclear (i.e. which occurred first?).
• No other study has ever found long-lasting brain changes from a single dose or two of cannabis, at least not in humans.  And no one has ever replicated these findings yet.
• Previous studies have been quite inconsistent in terms of the effects (or lack thereof) of cannabis use, even regular use, on brain structure, function, and cognition.  Some studies found increases in gray matter, others decreases, still others null.  Ditto for white matter as well.
• Given how the participants were European, it is particularly difficult to disentangle cannabis and tobacco use as the two substances are customarily mixed.  This is important because nicotine is a known neurotoxin to which the early adolescent brain appears to be exquisitely sensitive.
• The study apparently did not look at the brain effects of those who used cannabis but did not initiate until age 15 or older, so even if the effects are real, they may not necessarily be generalizable to people over 15.
• The practical significance of the findings is clear as mud right now.  Even the researchers aren't entirely sure what they mean.  Is it actually bad to have more gray matter, and compared to what exactly?  Is it disrupted brain development, or simply stimulated and enhanced neurogenesis?
• While greater gray matter in the study was correlated with differences in psychomotor performance contemporaneously for whatever reason, the only bad thing correlated with it two years later was generalized anxiety.  No other measures of psychopathology or performance were correlated at baseline or two years later.
• Come to think of it, if these 14 year olds were followed up two years later, why were their brains not scanned again a second time at 16, especially since there admittedly were many who were cannabis-naive at 14 who went on to use it two years later?
• And frankly, it really doesn't even pass the straight face test that a mere single dose or two of such a relatively mild psychoactive substance would be enough cause a long-lasting disruption to brain development, a process that occurs over several years.  To quote Paracelsus, "the dose makes the poison".  That, and Occam's Razor too.

Of course, the cliche that "more research is needed" certainly applies here, and the researchers indeed say as much.  They also plan to do a follow-up study as well in the near future.  Though if history is any indication, we should not hold our breath waiting for these results to be replicated.

Keep in mind that the infamous 2012 study that reportedly found persistently reduced IQs among adults who used cannabis before age 18, was debunked by 2014 study that found no correlation between adolescent cannabis use and IQ or exam performance (though heavy use beginning before age 15 was associated with slightly poorer exam results at age 16).  This latter study did control for tobacco, alcohol, and a host of other factors.  So it is very likely that soon another study will come a long and refute the first study discussed in this article, or perhaps find that any such effects are limited to the heaviest users, particularly those who began before age 15 or 16.  In fact, a 2018 systematic review of 69 studies of adolescent and young adult cannabis use and cognitive functioning found that reported adverse effects were much smaller in size than the prohibitionists like to claim, and generally tend to be temporary rather than permanent, even for frequent and/or heavy use.  And interestingly, no correlation with age of onset, though the mean age of study participants in these 69 studies was significantly higher than in the aforementioned Montreal study.

Other studies as well cast serious doubt on the scary claims of cannabis neurotoxicity as well, and most studies find weed safer than alcohol.

So what is the best takeaway from such studies?  It would seem that while occasional or moderate cannabis use is basically a non-problem, heavy and/or daily/near-daily use (unless medically necessary) should probably be avoided at any age, but particularly for people under 18 and especially under 15.  And while delaying the onset of use, or at least regular use, for as long as possible is probably wise for people under 18 and especially under 15, there is no hard scientific evidence that cannabis is any more harmful at 18 than it is as 21, 25, or even 30 for that matter.  Thus, there is no good reason to keep it illegal or set the age limit any higher than 18.  And even for people well under 18, the criminal law is still far too harsh a tool to apply to something like this that more likely than not turns out to be a non-problem.

The prohibitionist "scientists" and their pal-reviewers really seem to be grasping at straws now.  Apparently they think if they move the goalposts enough, they will score a touchdown.  But as we all know, that is not how science really works.

Does The Latest Brain Study Vindicate The 21 Drinking Age? Well, Not Exactly.

There is a new brain study making the headlines these days.  This study examined postmortem brains of three groups of people:  1) 11 people with alcohol use disorders (AUD) who began drinking consistently before age 21, 2) 11 people with AUD who began drinking consistently after age 21, and 3) 22 people who did not have any AUD at all, though many of them drank at least somewhat.  And among the three groups, only for the early-onset AUD group were epigenetic changes related to the expression of brain-derived neurotrophic factor (BDNF) found, particularly in the amygdala, which is responsible for regulating emotions.  These changes are thought to lead to difficulty regulating emotions, problems with anxiety, and even be part of the pathophysiology of alcoholism itself.

So what does this really mean, exactly?  First of all, the researchers seem to have arbitrarily picked 21 as the dividing line between early-onset and late-onset AUD drinkers, and made no further distinction within the early-onset group (i.e., before 15, before 18, first drink, first drunkenness, first regular drinking, etc.).  Secondly, the study looked at a small sample size of people with alcohol-use disorders (think alcohol abuse/dependence, alcoholism, truly heavy, heavy drinking for many years or decades), who at the time of death averaged well over 10 standard drinks per day and over 100 drinks per week, over 30+ years.  Males were also overrepresented (in fact there were zero women in the early-onset AUD group), and the early-onset group drank significantly heavier then the late-onset group.  It is probably safe to say that these drinkers are NOT representative of the vast majority of those who drink before 21, and given how early the onset of early-onset AUD drinkers tends to be, it would also be safe to say that this early-onset AUD group largely began drinking well before 18, if not before 15.  And even among the late-onset AUD group, the relative lack of epigenetic changes certainly did NOT stop them from becoming alcoholics in any case.

Furthermore, there is no temporality to this non-longitudinal study, so we don't know whether or not these epigenetic changes were due to pre-existing vulnerability or perhaps the early use of other substances such as that now-infamous neurotoxin, nicotine. (Most of the study subjects were smokers, apparently, and about 90% of adult regular smokers typically begin smoking before age 18).

Thus, this study tells us NOTHING about the difference between people in general who begin drinking at 18 versus 21.  NOTHING.  Nor does it vindicate the ageist abomination that is the 21 drinking age.  And anyone who claims otherwise is being, shall we say, "economical with the truth".

Latest Teen Brain and Cannabis Study More Smoke than Fire

The scary-sounding headline from a few weeks ago in USA Today reads, "Marijuana caused more damage to teens' brains than alcohol, study finds".  Yes, there was a study that claimed to find such results, but there is less here than meets the eye.

In other words, there's more smoke than fire.

The actual study itself is predictably behind a paywall, and we will not dignify such questionable research by paying for it, so we couldn't find the actual numbers and thus could not quantify any effect sizes or how long the reported effects lasted, but the abstract and several news articles summarize qualitatively the main findings.  The study, which involved nearly 4000 students from 7th through 10th grades in the greater Montreal area, longitudinally following them for those four years, asking questions about both alcohol and cannanis use and giving tests on memory and response inhibition.  Statistically significant correlations were noted between increased cannabis use and reduced performance on such tests, while interestingly for alcohol such correlations failed to reach statistical significance.

Again, no information about the size of such reported effects, and guess what?  SIZE MATTERS.  And so does duration.  Also, it say nothing about any such correlations beyond 10th grade, nor clearly distinguish between lighter and heavier use.  (The article did note that there were many more daily users of cannabis than alcohol, despite the fact that there were many more drinkers than tokers overall the sample.)  And it is very curious that the typically pro-21 mainstream scientific community are so willing to practically exonerate alcohol in such a study of teens--or perhaps they are simply alcohol supremacists.  And while the sample size and longitudinal nature of this study puts it head and shoulders about most other studies on the matter, given the aforementioned concerns it should still be viewed with caution in terms of causation.

Additionally, the study seems to be silent on the real "dark horse of drugs"--tobacco/nicotine.  Nicotine is a known neurotoxin, particularly during early adolescence, and is far more correlated with cannabis than alcohol use.  Thus, at least some of the reported effects in the study could in fact be due to tobacco, and/or perhaps other substances as well.

Keep in mind that the infamous 2012 study that reportedly found persistently reduced IQs among adults who used cannabis before age 18, was debunked by 2014 study that found no correlation between adolescent cannabis use and IQ or exam performance (though heavy use beginning before age 15 was associated with slightly poorer exam results at age 16).  This latter study did control for tobacco, alcohol, and a host of other factors.  So it is very likely that soon another study will come a long and refute the first study discussed in this article, or perhaps find that any such effects are limited to the heaviest users, particularly those who began before age 15 or 16.  In fact, a 2018 systematic review of 69 studies of adolescent and young adult cannabis use and cognitive functioning found that reported adverse effects were much smaller in size than the prohibitionists like to claim, and generally tend to be temporary rather than permanent, even for frequent and/or heavy use.  And interestingly, no correlation with age of onset, though the mean age of study participants in these 69 studies was significantly higher than in the aforementioned Montreal study.

Other studies as well cast serious doubt on the scary claims of cannabis neurotoxicity as well, and most studies find weed safer than alcohol.

So what is the best takeaway from such studies?  It would seem that while occasional or moderate cannabis use is basically a non-problem, heavy and/or daily/near-daily use (unless medically necessary) should probably be avoided at any age, but particularly for people under 18 and especially under 15.  And while delaying the onset of use, or at least regular use, for as long as possible is probably wise for people under 18 and especially under 15, there is no hard scientific evidence that cannabis is any more harmful at 18 than it is as 21, 25, or even 30 for that matter.  Thus, there is no good reason to keep it illegal or set the age limit any higher than 18.  And even for people well under 18, the criminal law is still far too harsh a tool to apply to something like this that more likely than not turns out to be a non-problem.

Have We Got the "Teen Brain" All Wrong? (Part Deux)

One thing that is commonly accepted as a truism in the USA is that crime, especially violent crime, is a young person's (and especially a young man's) vice.  It typically rises rapidly in the mid-teens and peaks around the late teens and very early twenties before rapidly and then gradually declining from then on, and it is often said that "the best cure for crime is a 30th birthday."  The statistics do indeed bear this out, but it is often accepted without question that the causes of this phenomenon are biological (particularly neurological and/or hormonal) as opposed to socioeconomic or cultural ones.

Well, a new study by researchers at Penn State seems to put the lie to the biological determinist theory.   While previous studies tended to look only at Western cultures (which all show a similar age pattern for crime), this one compared the USA to Taiwan instead.  If brain development (or lack thereof) is the cause, then the age pattern for crime should be pretty much the same worldwide, but it turns out that this was not the case for Taiwan.  Over there, crime peaked in the late twenties and early thirties, roughly a decade later than in the USA.  Thus, the researchers concluded that cultural factors, not biological/neurological ones, are primarly responsible for the crime patterns by age.   Notably, this is true even though the drinking age in Taiwan is 18, compared to 21 in the USA.

These findings also dovetail rather nicely with a 2015 study by renowned sociologist and youth-rights activist Mike Males.  Using crime data from California, he found that while the typical Western age-crime pattern for homicide (peaking at age 19) held true at first without controlling for poverty, once poverty was controlled for, that pattern basically vanished for all but the poorest communities, a group in which young people just so happen to be grossly overrepresented (and not just in California either).  And while some other studies have disagreed with such findings, those previous studies have generally failed to disentangle age, period, and cohort effects, greatly confounding the results.  Thus, especially in light of the Taiwan study, we can conclude that the traditional Western age-crime pattern is largely (if not entirely) a function of poverty, not age.  Which is actually good news, given that poverty is a much easier problem to solve (at least for a wealthy and Monetarily Sovereign nation like the USA) than any neurological issues or deeply-ingrained cultural factors could ever be.

It is very rare that a single study (or two) can overturn such an apparent mountain of evidence. Unless, of course, that "mountain" turned out to be a molehill all along--and a rather shaky one at that.

Have We Got the "Teen Brain" All Wrong?

One thing that is commonly accepted as a truism in the USA is that crime, especially violent crime, is a young person's (and especially a young man's) vice.  It typically rises rapidly in the mid-teens and peaks around the late teens and very early twenties before rapidly and then gradually declining from then on, and it is often said that "the best cure for crime is a 30th birthday."  The statistics do indeed bear this out, but it is often accepted without question that the causes of this phenomenon are biological (particularly neurological and/or hormonal) as opposed to cultural ones.

Well, a new study by researchers at Penn State seems to put the lie to the biological determinist theory.    While previous studies tended to look only at Western cultures (which all show a similar age pattern for crime), this one compared the USA to Taiwan instead.  If brain development (or lack thereof) is the cause, then the age pattern for crime should be pretty much the same worldwide, but it turns out that this was not the case for Taiwan.  Over there, crime peaked in the late twenties and early thirties, roughly a decade later than in the USA.  Thus, the researchers concluded, that cultural factors, not biological/neurological ones, are primarly responsible for the crime patterns by age.   Notably, this is true even though the drinking age in Taiwan is 18, compared to 21 in the USA.

It is rare that a single study can overturn such an apparent mountain of evidence.  Unless, of course, that "mountain" turned out to be a molehill all along--and a rather shaky one at that.