Another promising avenue for future research direction, which gained increasingly more attention, is to identify target systems involved in fear extinction and explore interventions that enhance targeted approach of exposure-based psychotherapies for PTSD such as DCS, oxytocin, and MDMA (Heinrichs et al., 2003; Young, Andero, Ressler, & Howell, 2015). This evidence concerns the gene OXT and post-traumatic stress disorder.