In the publication “Hormonal Changes and Couple Bonding in Consensual Sadomasochistic Activity,” Sagarin examined 58 participants, consisting of both heterosexual couples and same-sex couples, as they participated in a BDSM scene. Surveys were conducted and saliva samples were gathered before and after the scene to measure the participants’ levels of cortisol, a hormone that is released in response to stress. Sagarin found that while cortisol levels rose for people taking on submissive roles during the scenes, it stayed the same for people taking on dominant roles, which he attributes to the bottom giving up control of the situation and not knowing what activity will happen next. Dr. Brad Sagarin studies deception, jealousy and infidelity; evolutionary psychology; human sexuality and more.   According to Sagarin, perhaps the most important  finding was that couples displayed acts of caring before, during and after the scenes, which he said shows that these often intense activities happen within a positive relationship context. “These activities are not happening where someone is walking into a room with a whip, smacking someone else with it and walking out,” he said. “There is continued feedback going on so both can check in and make sure they’re having a good time, and when the scene is over, couples would typically sit quietly, would cuddle, would talk. This process that is often called ‘after care’ is an important part of reconnecting after these activities.”