“Smoking marijuana affects peoples’ impulsivity, attention, memory, cognition and decision-making abilities,” the authors of the study claimed in a news release. “That’s been scientifically proven.”
Well, yeah, man … at least if the stuff’s any good.
The researchers claim their findings are “important because they demonstrate a potential, negative side effect of chronic marijuana use.”
Hell, in this economy, caring less about money seems like a survival trait, to me.
”Understanding how marijuana influences the perception of what is ‘negative’ may help explain continued marijuana use and aid in the development of effective strategies for treatment therapies,” said lead author Michael J. Wesley, Ph.D., department of Physiology and Pharmacology at Wake Forest Baptist. (Translation: You’re bad, we’re Baptists, and we’re here to help you.)
“Published data suggests that marijuana use is increasing, both recreationally and medically,” said Captain Obvious, I mean Dr. Wesley. “However, the misperception that it’s harmless is also rising. It’s imperative that we begin analyzing the effects of long term, heavy marijuana use.”
Published by Psychiatry Research in the January 2011 issue, Wesley’s study was supported by grants from the — surprise, surprise! — National Institute on Drug Abuse (NIDA), which won’t fund studies unless they are specifically constructed to search for something, anything negative about pot.NIDA claimed in December 2010 that regular marijuana use is on the rise among teenagers, citing an increase of more than 10 percent in students in 8th, 10th, and 12th grades.
In the study, researchers said that marijuana users “performed poorly” on the Iowa Gambling Task (IGT), which is a complex decision-making task in which participants make choices under ambiguous conditions and win or lose money based on their choices.
The goal of the IGT is to use the feedback of the wins and losses to guide future choices toward supposed “safe options” that result in winning more and losing less.
Sixteen “chronic marijuana users” and 16 controls, or non-users, performed a modified IGT in a magnetic resonance imaging (MRI) scanner. Performance was tracked and functional brain activity in response to early wins and losses was examined.
Researchers were looking to see if the perceived “poor performance” of marijuana users was related to differences in brain activity while evaluating the positive and negative information conveyed by wins and losses during the early, strategy development phase of the IGT.For the control group, after multiple exposures to early large monetary losses, they began to choose “safer,” less negative options on the task. In contrast, the damn potheads — I mean the marijuana users — generally failed to alter their selection patterns and continued to make what the researchers deemed “disadvantageous choices” throughout the task.
The researchers said that this was because the marijuana users were “less sensitive to the negative feedback” during strategy development. I call bullshit; the pot smokers obviously just weren’t taking the money game as seriously as the stressed-out straights.
“The marijuana users appear to have a blunted response to losing,” Wesley said uncomprehendingly but appropriately. “They don’t figure out a strategy to avoid monetary losses and this is associated with a decreased functional brain response to the early, negative information that guides the other group to safer choices.
“The bottom line is that it looks like they don’t care as much if they lose,” Wesley said.
Larger Study Showed No Impact On Decision Making
The results of the study contradict clinical trial data from a large study in 2007 which indicate that marijuana intoxication does not adversely affect decision making.
In that study, published in the Journal of Clinical and Experimental Neuropsychology, investigators at New York State’s Psychiatric Institute and Columbia University looked at the impact of acute cannabis intoxication on the decision-making abilities of 36 subjects, as assessed by, you guessed it, the Iowa Gambling Task.
Volunteers in that study completed the IGT once sober and three times after smoking cannabis or a placebo. Though using cannabis increased the time required for subjects to complete their tasks, volunteers’ accuracy was not adversely affected by pot.
“Advantageous card selection and money earned on the task were not disrupted by marijuana,” the authors concluded. “These data are consistent with previous findings that indicated that speed of performance on tests of executive function, but not accuracy, is disrupted in experienced marijuana users during marijuana intoxication.”