Today hypnotherapy is used to provide therapeutic remedy for depression, pain, substance use disorders, and certain traumas, uses that are supported to a certain extent by research evidence. But many still consider hypnosis more of a cheap magician’s trick than legitimate clinical medicine.
Perhaps this is because very few of us are easily hypnotized: Only about 10 percent of the population seems to respond well to it. Researchers and clinicians tend to use one of two scales to measure an individual’s susceptibility: the Stanford Hypnotic Susceptibility Scale, typically used on individuals, and the Harvard Group Scale, which is used on groups primarily to identify potential subjects for research.
How hypnotizable a person is may have a genetic component, according to twin studies. And yet, concrete insights into what separates the hypnotizable from the rest of us are scarce. Research from the 1980s suggests a facility for becoming “absorbed” in a task, such as reading or a theater performance, might make a person more susceptible to hypnosis. Others have found a correlation between hypnotizability and one’s tendency toward dissociation, a mental process of disconnecting from one’s thoughts, feelings, and memories that can develop as a defense mechanism to trauma.
