Long-Term Cannabis Use May Blunt the Brain’s Motivation System
Researchers found that dopamine levels in a part of the brain called the striatum were lower in people who smoke more cannabis and those who began taking the drug at a younger age. They suggest this finding could explain why some cannabis users appear to lack motivation to work or pursue their normal interests.
The cannabis users in the study had their first experience with the drug between the ages of 12 and 18. There was a trend for lower dopamine levels in those who started earlier, and also in those who smoke more cannabis. The researchers say these findings suggest that cannabis use may be the cause of the difference in dopamine levels.