The study, which was led by researchers at The University of New Mexico (UNM), was published in The Journal Scientific Reports. This study is the first to show the non-medical effects of cannabis and the positive psychological outcomes for young healthy adults.

Researchers refer to existing research on cannabis and its user effects. They note that most of the literature is focused more on health and pharmacodynamics than other psychological normative effects.

“Most investigations on the effects of using cannabis have focused on either negative consequences of cannabis addiction or on the physical health effects of cannabis use,” said Jacob Miguel Vigil, lead investigator and assistant professor at UNM Department of Psychology. “Almost no formal scientific attention has been devoted to understanding other psychological and behavioral effects of consuming the plant, despite it being so widely used throughout human history.”

With controls for the participant’s age, sex, ethnicity, and childhood socioeconomic status, researchers examined 146 healthy college students between 18 and 25 years of age with varying, detectable levels of THC in their urine.

They found that marijuana users scored better than THC-free people on moral fairness, prosocial behavior and empathy. Cannabis users and those who did not use it had the same results in terms of their anger, hostility and trust of others. They also scored higher on measures of extraversion, fear interpretation, and facial threat interpretation.

Also, the findings indicate that cannabis may contribute to a shift away from self-centered self-concepts and towards selflessness. Among men, cannabis users scored higher on “agreeableness,” and most of the observed differences in prosociality between cannabis users and non-users had a correlation with the duration of time since participants last used cannabis.

These results indicate that cannabis’ effects in these areas are temporary. In other words, the extra kindness you get from cannabis could disappear if your consumption ceases.

“The transience of the effects supports that cannabis is triggering behavioral and perceptual changes rather than that cannabis users and non-user differ fundamentally in their baseline approaches to social interactions,” said co-author and Associate Professor Sarah Stith, UNM Department of Economics.

Co-author Tiphanie Chanel called the research “groundbreaking,” adding, “I hope that this work can help pave the road to more fully explore the effects of cannabis on human interactions and wellbeing.” 

Research shows that personality development occurs during young adulthood and adolescence, which is when people form prosocial habits and behaviors. The researchers stated that further psychological research needs to be done in this age group, including among those who use cannabis.

The cross-sectional model of the study didn’t enable researchers to track participants over time, particularly pre- and post-cannabis use. Researchers also pointed out that this sample was small, and therefore may not have been representative of the wider community. This limits the ability to generalize the results. The sample came from an institution with more diverse students than traditional students. However, the researchers note that the number of students who are not in college is still very limited.

Where there is still more to explore, Vigil refers to cannabis as a “super medication,” not only effective for treating an array of health conditions but now displaying potential to improve a person’s psychological health.

Vigil added, “Prosociality is essential to society’s overall cohesiveness and vitality, and therefore, cannabis’ effects on our interpersonal interactions may eventually prove to be even more important to societal wellbeing than its medicinal effects.”