Cannabis users experience altered brain activity when multitasking

A new study, published in the Journal of Psychopharmacology, has shown that regular cannabis users exhibit altered patterns of brain activity during cognitive tasks that require flexible thinking. The research used magnetoencephalography (MEG) to examine brain activity in the dorsolateral and dorsomedial prefrontal cortex. The results showed that cannabis users had weaker neural responses compared to non-users when switching tasks, despite similar levels of performance. This suggests that frequent cannabis use may affect cognitive flexibility by altering theta oscillations, which are essential for task shifting and adaptability.

The study and its methodology

The study included both cannabis users and non-users to compare their brain activity during task shifting. The researchers used a technique called magnetoencephalography (MEG), which allows detailed measurement of the brain’s magnetic field. Participants performed various cognitive tasks that required them to quickly switch from one task to another, which tested their cognitive flexibility.

Results and interpretation

The findings from the study showed that cannabis users had weaker activity in the dorsolateral and dorsomedial prefrontal cortexes compared to non-users. These areas of the brain are critical for planning, decision-making, and adapting to new situations. Despite these differences in brain activity, both groups performed equally on the tasks. This suggests that cannabis users may be developing alternative strategies to compensate for their altered brain activity.

Implications for future research

The researchers believe that these findings may have important implications for understanding how long-term cannabis use affects brain function and cognitive abilities. Further research can investigate whether these changes are reversible and how they may affect daily functions and long-term cognitive health.