Marijuana use reduces dopamine in the brain

The dopamine  is a transmitter in the brain crucial for the movement, thought and memory; but, above all, we know as the “hormone of pleasure”. Now, a new study conducted by researchers at the Medical Center of Columbia University in New York (USA) has revealed that marijuana could compromise the dopamine system.

Previous studies have found that drugs considered more “forceful” like heroin and cocaine decreased dopamine release; but, until now, he had never associated this result to marijuana.

Most addictions  to drugs end up blunting the release of dopamine during the greater dependence. On this basis, the researchers wanted to know if marijuana was linked to similar to these effects. To do this, they had the participation of 11 adults between 21 and 40 years, large marijuana (smoked marijuana daily), and also with 12 adults who did not consume any substance.

Experts used the technique of positron emission tomography (PET) to track a molecule that binds to the dopamine receptors in the brain in order to measure the release of this neurotransmitter in the brain striatum and in other regions such as the thalamus, midbrain and globus pallidus.

During the weeklong experiment, participants were unable to use marijuana to prevent images would measure the effects of this substance. The results showed that compared with the control group, the striatum of volunteers taking marijuana had a lower level of release of dopamine; so did other regions. All of them had lower levels of dopamine, which is associated with inattention and problems in learning and working memory.

” We do not know whether the decrease in dopamine was a preexisting condition or results of cannabis. But the conclusion is that long – term, cannabis use may endanger the dopaminergic system, which could have a variety of negative effects on learning  and behavior , “says the leader of the work.