Ever wonder why some people are so grumpy before their daily wake and bake? A new study out of the University of Texas at Dallas may have answered that question by looking at that the reward response that long-term cannabis users have to everything that's not pot.
The research, which took control groups of 59 regular users and 70 non-users, had participants rate their urge to light up after being shown images of bongs and pipes alongside pictures of various fruit, like bananas and apples.
The scientists found that the pot smokers had highly-increased brain activity in the reward regions of their brain when presented with weed paraphernalia, but not nearly as much when presented with the food.
According the study, researchers made sure to account for potential biases—such as mental illness or traumatic brain injury—and found that pot users experienced more behavioural problems (irritability and family issues) when they weren't high. The issues only went away when the marijuana users' reward centres lit up normally, after they were exposed to marijuana again.
"The relationship between response to cannabis cues and self-reported marijuana problems suggests that this mechanism underlies the transition to problematic use or dependence via increased sensitivity to cannabis cues," the paper reads.
In short, the research suggests that marijuana fucks up the human brain's natural reward process. Unlike normal users, who would get sensation or excitement out of seeing regular mood-lifters like sugar or food, heavy cannabis users were only satisfied when they were treated to the sight of a joint or marijuana-related objects.
It should be noted, however, that while the study examined cannabis users who had an average span of 12 years of use, it also adds that further research is needed to isolate whether people with low reward activity already are more drawn to smoking cannabis than others.
This isn't the first study to come out swinging at the idea that pot is a relatively harmless drug. Last month, researchers found that teenage users of pot were more likely to hallucinate and experience symptoms of psychosis than their sober friends. Experts have also suggested that the legal age for purchase of marijuana be set at 25 when Canada goes to legalize the drug next year.
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