Each session lasted at least 4.5 hours, or until all effects of the drug had worn off. During that time, participants stayed in a laboratory testing room, and social interaction was limited to contact with a research assistant who helped administer cognitive exams.
A moderate dose of MDMA was found to significantly increase feelings of loving, friendliness and playfulness, the researchers said, whereas the low dose of MDMA boosted feelings of loneliness.
The moderate dose also prompted a drop in the ability to accurately recognize fear in other people's faces, determined by having the participants look at a range of photos, the study found, but it did not affect the ability to perceive the shifting cues in a person's eyes or voice, determined by having the participants listen to a series of audio clips.
This effect, the Bedi and his team suggested, could help people improve their social skills by shielding them from the negative emotions of others.
In a twist, the researchers also found that methamphetamine similarly prompted feelings of friendliness and loving. In fact, those who took the drug actually rated themselves as more sociable than those taking MDMA.
As a warning, the researchers noted that MDMA might indeed facilitate socializing, but it also might impair a person's perceptive abilities and thus prompt risk-taking.
Nonetheless, the researchers suggested that MDMA might help people with PTSD as well those with autism, schizophrenia or antisocial personality disorder cope with a variety of emotional difficulties.
"More controlled research is needed to establish whether MDMA can safely and effectively add to psychotherapy for some conditions and, if so, what the mechanisms of these effects are," Bedi said.
Dr. Michael Mithoefer, author of the earlier study on MDMA and PTSD, also urged further exploration of the medicinal potenti
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