Traumatic events can lead to lasting personality changes, especially increased neuroticism. In a randomized trial of MDMA-assisted psychotherapy for chronic, treatment-resistant PTSD, changes in openness—but not neuroticism—moderated the link between reduced PTSD symptoms and the treatment. Patients showed increased openness and decreased neuroticism from baseline to long-term follow-up. These preliminary findings suggest MDMA-assisted psychotherapy may alter personality structure beyond just relieving PTSD symptoms, leading to enduring personality change.
In a Phase II clinical trial of MDMA-assisted psychotherapy for chronic, treatment-resistant PTSD, increases in Openness and decreases in Neuroticism personality traits were linked to greater symptom reduction, regardless of treatment condition. Participants receiving MDMA showed the largest gains in Openness, which predicted lower PTSD severity. The authors propose that MDMA, combined with psychotherapy, may facilitate a reorganization of mental experience through altered brain pathways, rather than through psychological learning alone.