Oxytocin as a moderator of hypnotizability

Since hypnosis was popularly recognized in the nineteenth century, the phenomenon of hypnotizability has remained poorly understood. The capacity to increase hypnotizability has important implications because it may increase the number of people who can benefit from hypnotic interventions for psychological and medical conditions. Current theories emphasize that rapport between hypnotist and subject is pivotal to motivate the respondent to engage in strategies that allows them to suspend reality and respond to suggestions. The neuropeptide oxytocin is implicated in social bonding, and enhances a range of social behaviors in animals and humans. This study tested the proposal that oxytocin administration, which enhances social bonding in humans, may enhance hypnotic responding by administering intranasal spray of oxytocin or placebo prior to hypnosis in 40 low hypnotizable male subjects. When low hypnotizable individuals were administered oxytocin via nasal spray, their level of hypnotic responding increased significantly compared to hypnotic responding levels prior to oxytocin administration. This is the first demonstration of a neurochemical basis for hypnotic responding, and points to a potential neural mechanism to explain hypnotizability.