The 2018 Monitoring the Future Study shows that the past 12-month and past 30-day marijuana use in young adult student (19-22 years) are at the highest level since 1983. The aim of this study was to look at the influence of frequent marijuana use and how it impacts risky decision-making in college students. Participants had to abstain from marijuana use for 12 hours before the study to avoid any withdrawal symptoms.
To complete the study, 65 college students (18-22 years) were recruited. Exclusion criteria included current use of psychiatric disorders, neurological/medical illnesses, significant substance use history, and several others. All participants provided a urine sample and completed a breathalyzer test. Participants were split into a group of healthy controls or marijuana users based on results of the urine test. They completed a brief demographic questionnaire and an Iowa Gambling test on a computer. This test involved a card game with goal being to win as much money as possible. Participants chose between different decks of cards that were associated with different winnings and penalties.
Results from this study showed participants using marijuana had lower net scores for the gambling test. The group of marijuana users were also found to have selected more cards from the disadvantageous decks. The disadvantageous decks had higher winnings but were associated with greater penalties which outweighed the increased winnings. The researchers did not find any significant group differences in mean reaction time between the healthy control group and the marijuana users. While this study provides important findings about potential differences in risky decision-making in young adults using marijuana, more research should be done on whether the difference is pre-existing and increases vulnerability for marijuana use itself, or if the differences are a result of the marijuana use.
Take Away: The goal of the current study was to look at the influence of frequent marijuana use and how it may impact risky decision-making in young adults. 65 college students were recruited and each the participants were split into a healthy control group and a marijuana user group. They were asked demographic questions and then an Iowa Gambling test was administered on the computer. It involved a card game with the goal being to win money. The researchers found that the group of marijuana users had lower net scores due to selecting more cards from the disadvantageous decks. While this study provides important findings about potential differences in risky decision-making in young adults using marijuana, more research should be done whether the differences are pre-existing.