On Hypnotizability

What is hypnotizability?

Very early in the clinical and scientific exploration of hypnosis, it was apparent that some people respond more than others to hypnotic suggestions. Nowadays, we have plenty of evidence to support this observation and identify factors that come into play when we use hypnosis to improve our lives.

Hypnotizability (also: hypnotic responsiveness, hypnotic suggestibility) represents a person’s ability to experience physiological, sensory, behavioral, cognitive, and emotional changes in response to suggestions given during hypnosis [1]. Hypnotizability is stable even after 25 years [2], with slight increases throughout aging [3]. More than two-thirds of adults are hypnotizable, with about 15% having high hypnotizability [4].

Studies show that hypnotizability contributes to the effectiveness of hypnosis sessions, such as when targeting pain [5], weight loss [6], smoking [7], and potentially for anxiety and even asthma [8].

How is hypnotizability measured?

There are many tests for hypnotizability. Some were designed to be used more commonly in research and often take longer, while others are shorter and therefore more practical for clinical use. The most common research-based tests to measure hypnotizability are the Harvard Group Scale for Hypnotic Susceptibility (HGSHS; for groups) and the Stanford Hypnotic Susceptibility Scale (SHSS; for individuals). In his clinical practice, Dr. Spiegel is using a test he helped to design and develop, called the Hypnotic Induction Profile (HIP), which is substantially shorter than the HGSHS and the SHSS and has two scales to inform about hypnotizability: the induction score (0-10 points; with scores above 8 considered high hypnotizability) and the eye-roll scale that has been used as a quick correlate of hypnotizability.

Brain Abilities

Previous and ongoing research has been undertaken to unravel how our brains facilitate hypnotizability. Neuropsychological studies have shown that the brains of individuals high in hypnotizability function differently than those with lower hypnotizability, even outside the context of hypnosis [1] [9,10].

Moreover, people with chronic pain disorders seem to manage their pain slightly better if they are higher in hypnotizability [11]. In hypnosis, having high hypnotizability is also related to experiencing suggestions as being effortless and happening by themselves [12].

Using functional magnetic resonance imaging (fMRI; a form of neuroimaging), Dr. Spiegel’s laboratory showed that brain networks of highly hypnotizable individuals communicate differently than those with low hypnotizability. To dive deeper, check out our article about How Hypnosis Works in the Brain.

Genetics

Evidence from a twin study showed that hypnotizability is heritable [13]. Supporting this finding, recent research has identified several genes associated with hypnotizability. To learn more about the specific genes, read our forthcoming article about Hypnosis and Our Genes. Because of how we think about genetics, it is important to note that while some genes play a role in hypnotizability, they are only one piece of the puzzle and not the whole picture.

Context Matters

When we measure how well we respond to hypnosis, we need to consider the context. Do you want hypnosis to work? Are you actively resisting? There are different aspects of the context we know could impact how much a person benefits from hypnosis. For example, the more motivated you are for hypnosis to work [14], and the more you expect it to work, the better effect it will have (in academic terms, this is called “expectancy” [15]). In fact, in some cases, simply using the word “hypnosis” can increase the effect of the session [16]. Expectancy is shared between hypnosis and placebo, but don’t mistake hypnosis for being a placebo response. Placebo requires you to believe you received an actual “medication” or substance (where you also have high expectancy), and that belief fuels the effect. In hypnosis, no deception is needed. Lastly, the setting in which one is being tested can also change the final score. Some people can respond differently to hypnosis depending upon whether they are in a group or by themselves.

Limitations to Hypnotizability Scores

Hypnotizability is most often presented as a summary score of our responsiveness to different sets of suggestions. However, people can differ in their ability to experience some forms of suggestions. For example, one person can respond better to suggestions about feeling the body, while another responds better to suggestions about emotional states. Even though they may have an identical hypnotizability “score,” they respond differently to various suggestions. For this reason, a person’s hypnotizability score can help us estimate the likelihood of benefit, but it does not determine whether this person will or will not benefit from hypnosis. Remember, people can experience great change with hypnosis even if they seem to score “low” on hypnotizability [4].

Bottom Line

Hypnotizability is our ability to experience changes in response to suggestions in hypnosis. It is impacted by psychological, biological, and social factors and can help us estimate how much a person can benefit from hypnosis. While most people score as hypnotizable, even those with low hypnotizability can benefit from hypnosis. Don’t get hung up on your score – give it a try! Whatever the outcome, your experience will enhance your ability to address and resolve problems.  

References

  1. Elkins, G. R., Barabasz, A. F., Council, J. R. & Spiegel, D. Advancing Research and Practice: The Revised APA Division 30 Definition of Hypnosis. Int. J. Clin. Exp. Hypn. 63, 1–9 (2015).

  2. Piccione, C., Hilgard, E. R. & Zimbardo, P. G. On the degree of stability of measured hypnotizability over a 25-year period. J. Pers. Soc. Psychol. 56, 289–295 (1989).

  3. Page, R. A. & Green, J. P. An Update on Age, Hypnotic Suggestibility, and Gender: A Brief Report. Am. J. Clin. Hypn. 49, 283–287 (2007).

  4. Lynn, S. J., Meyer, E. & Shindler, K. Clinical correlates of high hypnotizability. in The Highly Hypnotizable Person: Theoretical, Experimental and Clinical Issues (eds. Heap, M., Brown, R. J. & Oakley, D. A.) 187–212 (Routledge, 2004).

  5. Milling, L. S., Valentine, K. E., LoStimolo, L. M., Nett, A. M. & McCarley, H. S. Hypnosis and the Alleviation of Clinical Pain: A Comprehensive Meta-Analysis. Int. J. Clin. Exp. Hypn. 69, 297–322 (2021).

  6. Barabasz, M. & Spiegel, D. Hypnotizability and weight loss in obese subjects. Int. J. Eat. Disord. 8, 335–341 (1989).

  7. Spiegel, D. et al. Predictors of smoking abstinence following a single-session restructuring intervention with self-hypnosis. Am. J. Psychiatry 1090–1097 (1993).

  8. Lynn, S. J., Shindler, K. & Meyer, E. Hypnotic Suggestibility, Psychopathology, and Treatment Outcome. Sleep Hypn. 5, 17–25 (2003).

  9. Faerman, A. & Spiegel, D. Shared cognitive mechanisms of hypnotizability with executive functioning and information salience. Sci. Rep. 11, 5704 (2021).

  10. Srzich, A. J. et al. Does hypnotic susceptibility influence information processing speed and motor cortical preparatory activity? Neuropsychologia 129, 179–190 (2019).

  11. Faerman, A. et al. Hypnotic predictors of agency: Responsiveness to specific suggestions in hypnosis is associated with involuntariness in fibromyalgia. Conscious. Cogn. 96, 103221 (2021).

  12. Polito, V., Barnier, A. J., Woody, E. Z. & Connors, M. H. Measuring agency change across the domain of hypnosis. Psychol. Conscious. Theory Res. Pract. 1, 3–19 (2014).

  13. Morgan, A. H. The heritability of hypnotic susceptibility in twins. J. Abnorm. Psychol. 82, 55–61 (1973).

  14. Patterson, D. R., Adcock, R. J. & Bombardier, C. H. Factors Predicting Hypnotic Analgesia in Clinical Burn Pain. Int. J. Clin. Exp. Hypn. 45, 377–395 (1997).

  15. Kirsch, I. Hypnosis and Placebos: Response Expectancy as a Mediator of Suggestion Effects. An. Psicol. 12 (1999).

  16. Gandhi, B. & Oakley, D. A. Does ‘hypnosis’ by any other name smell as sweet? The efficacy of ‘hypnotic’ inductions depends on the label ‘hypnosis’. Conscious. Cogn. 14, 304–315 (2005).

  17. Hoeft, F. et al. (2012) Functional brain basis of hypnotizability. Archives of general psychiatry 69, 1064-1072. 10.1001/archgenpsychiatry. 2011.2190

About the author:

Afik Faerman, Ph.D. is a postdoctoral scholar at Stanford University. He completed his doctoral training in clinical psychology with an emphasis in neuropsychology, and his clinical training at the University of California, San Francisco (UCSF) and Baylor College of Medicine in Houston, TX. Afik’s research centers on identifying key neurocognitive mechanisms in clinical change, focusing on hypnosis, pain, and sleep. His research was supported and acknowledged by the American Psychological Association, the Society for Clinical and Experimental Hypnosis, and the American Society for Clinical Hypnosis.