Friday, September 20, 2013
A couple of my students have noticed a recent report on a new study linking marijuana use and a lack of motivation. And one of these students earned extra credit by doing the following effective formal write up of the study and some of the questions it prompts:
As we consider the downsides of a potential legalization regime, one of the questions that remains hotly debated is: “what exactly are the health/lifestyle hazards of marijuana use?” While information (and misinformation) abound, a new study may buttress those who condemn marijuana usage because they feel it encourages laziness and a lack of motivation in youth.
The study, conducted by researchers at three London-based universities, focused on cannabis users who had had “psychotic-like experiences” while using cannabis and found that heavier users (“HU”)* and younger users (i.e. users in their adolescence, or “YU”) had decreased levels of dopamine compared to peers. The lowest levels were found in younger heavy users (“YHU”). This result surprised the researchers, who were expecting the opposite because psychosis has been tied to increased levels of dopamine.
While the research took a different turn, the researchers tied this finding to another theory: the lower dopamine levels may explain the “lack of motivation” that many attribute to heavy users of marijuana. The limited parameters of the study does not provide any hard science on users who have not experienced psychotic episodes, but Dr. Michael Bloomfield, who led the study, believes that “the findings would apply to cannabis users in general, since we didn’t see a stronger effect in the subjects who have more psychotic-like symptoms.” However, he believes that this would need more testing.
It is worth noting that a recent study by researchers at Columbia University, concentrating on users who averaged 517±465 puffs per month (“ppm”), had similar results with regard to the YHU population, but overall found that compared to other addictions, such as alcoholism and cocaine and heroin dependence, mild or moderate cannabis addiction was not associated with decreased dopamine levels.
While this data and debate is certainly intriguing, how does it relate back to our analysis of the perils of a legalization regime? Several questions are unanswered: (1) How does this data compare to alcohol use? (2) What about YHUs of alcohol? (3) Can a regulatory system deal with these problems effectively by mitigating the YHU numbers? (4) Has our current regulatory regime had an impact with regard to YHUs and alcohol?