Dr. George Ricuarte used a PET scan of MDMA users brains as an indicator for how much damage the drug caused. The scans showed that there was indeed brain damage in users. It also showed that an increase in the frequency of use leads to an increase in brain damage. The PET scan actually showed a 20-60% reduction in healthy serotonin cells.

Another study, by German researchers in 2003, also used PET scans to show the difference between brain damage in people frequently using MDMA and those that have not used in 20 weeks. The results show that MDMA users that stop taking ecstasy 20 weeks before the PET scans showed improvement in their serotonin levels.

PET scan tells all