This story is over 5 years old.


Cannabis Use Can Elicit 'Autistic-Like' Behavior

According to a new report, smoking weed may affect your ability to empathize with people and process emotions. We spoke to the study's author, who says researchers have already approached her about the use of cannabis to treat autism.
Photo by Zoa Photo via Stocksy

Following a new report published in the scientific journal PLOS ONE, the archetype of the stoner as the essence of chill might have to be more accurately updated to icy. Researchers at Colorado State University, who studied the effects of cannabis on emotion processing, found that people who smoke weed displayed a stronger response to negative emotions than their herbally sober counterparts and had a lessened ability to empathize. Perhaps this why Rihanna, of poolside blunt smoking fame, doesn't want to hear about your crisis.


Over the course of two years, Dr. Lucy Troup studied the long-term effects of 70 participants who either smoked cannabis, smoked casually, or smoked chronically, according to self-reported data. The study took place in three parts: an implicit emotion test, an explicit emotion text, and an empathy test, where volunteers were asked to view a facial emotion—positive, neutral, or negative—and were rated on their ability to empathize. One of the most surprising results was that cannabis users generally had lower empathy ratings than the control group.

Read more: This Is What Happens When You Drink an Entire Bottle of Weed Lube

This result has opened up questions around weed and autism, though this current study has not looked directly at the link between the two. "I've been approached by a number of researchers who are very interested in the use of cannabis to treat autism and if the two are related or causal," Dr. Troup says. "We found that when you ask a cannabis user to think about other people's emotions and relate to them, it's harder for them. That inability to empathize would be a parallel to autistic-like behaviors. Certainly, this is something to think about."

Additionally, Dr. Troup also asked participants to undergo an implicit emotional task. Both the control group of non-smokers and the cannabis users were hooked up to an electroencephalogram (EEG) while they were shown faces with positive, neutral, and negative facial expressions, but asked to focus on the sex of the face displayed. Later they were asked to recall the emotions they were shown, and the cannabis users faired much worse with this task than non-cannabis users. From these results, Dr. Troup infers that weed inhibits a person's ability to intuitively identify emotions when they're not explicitly focusing on them.

We found that when you ask a cannabis user to think about other people's emotions and relate to them it's harder for them.

To measure explicit emotion processing, participants viewed faces depicting positive, neutral, and negative facial expressions—this time focusing on them explicitly—and were asked to identify the emotions displayed. Typically, Dr. Troup says, when measuring brain waves independent of weed use, people demonstrate a stronger reaction to positive emotion. But Dr. Troup's study, the resulting EEG showed that stoners had the greatest response to negative facial expressions.

The study's findings indicate that cannabis use can affect how we process emotion. Dr. Troup explains that this data could give some insight into how cannabis is used inadvertently to self-medicate and regulate mood disorders. "In some cases, weed could be deadening down negative emotions, but it could be the other way. Because [some cannabis users] aren't able to process negative emotions it can impact them socially. They can't recognize when others are angry. They can't recognize when they're angry. There's also so much individual variability," she says. "Is cannabis acting as an anti-depressant and pushing negative emotions down? Or is it the opposite? That's the money question."