There is a view that hypnotic suggestibility is an individual trait, one that is relatively stable. The variability reflects the general tendency (among the population) to respond to hypnosis and hypnotic suggestions. When measuring hypnotic suggestibility as a single trait, it is suggested that just 10-15% of the population are in the low range of hypnotic suggestibility, whereas around 70-80% are in the medium range and about 10-15% are in the highly hypnotically suggestible range. However, there could be some variance in these figures, if sub-skills are considered separately.
It has been suggested that hypnotic suggestibility could be sub-categorised into different types of response. Movement-based tests, using the concept of ‘ideomotor response’ with thoughts becoming actions, include tests such as magnetic fingers, magnetic hands and heavy and light hands (bucket and balloon):
There are also challenge-based tests, often involving inhibition of movement, such as with hand lock, or catalepsy of muscle groups. Another sub-category would then relate to cognitive-perceptual focused tests, such as number amnesia, or positive/negative hallucinations.
In the realm of street hypnosis, hypnotic suggestibility tests are an effective starting point, permitting the hypnotist to rapidly assess the participant, whilst, especially with movement and challenge-based tests, providing any spectators with something visual to watch, keeping them engaged and potentially entertained. In this context, they also give the participant an easy start to the hypnosis process, whilst building confidence in the hypnotist and their own ability to respond.
For the stage or entertainment hypnotist, the suggestibility test at the beginning is a great way of building audience engagement. Then, when there are volunteers, further, more demanding tests, can help the stage hypnotist filter out the less-strong responders, and keep the most responsive individuals. However, suggestibility tests tend not to identify personality types, and a volunteer may be a high responder, but not of an extravert/playful mindset, and thus may not remain a volunteer for the duration of the performance.
Are suggestibility tests just for street and stage hypnotists?
When a hypnotherapist is giving an informative hypnosis presentation, a demonstration of some variety is an excellent way of highlighting the power of the mind. Using a simple hypnotic suggestibility test, such as the Lemon test, with everyone present, is a great way of engaging the audience and helping them understand individual variance within hypnotic response. Then, a movement or challenge-based test can be helpful if the hypnotherapist then wishes to select a volunteer for a hypnosis demonstration, particularly one involving hypnotic phenomena or the senses.
So, is there any possible benefit in using suggestibility tests with hypnotherapy clients? Some hypnotherapists, even hypnotherapy trainers, consider that hypnotic suggestibility testing is just for stage and street hypnotists. Further, that if a client ‘fails’ a test, they can lose faith in the therapy process. However, there is no need to call a suggestibility test ‘a test’. Instead, it can be phrased as a ‘warm-up activity’ or ‘pre-hypnosis exercise’, and the results can always be reframed positively, regardless of how much or how well they respond.
Also, sadly, some hypnotherapy schools are reluctant to teach hypnotic suggestibility testing, perhaps as many are more direct or authoritarian and are performed conversationally (without ‘scripts’). Thus, some hypnotherapists lack the direct training or skills in order to use suggestibility tests. Yet, they are not complex to learn, and there are multiple learning streams, including online and in person workshops, peer support groups and even many excellent and informative books and videos/DVDs.
As a hypnotherapist, you may wonder why it would be useful to ascertain a client’s hypnotic suggestibility. What will you gain from that information? What will the client gain? There are several positive benefits for the use of suggestibility tests within the hypnotherapy session. Firstly, it is a strong resource within the assessment process, enabling the therapist to consider different aspects of the client’s response and to more effectively select appropriate induction and therapy approaches. For example, if the client is more kinaesthetic and prefers a dynamic approach, a visual, slow and gentle permissive induction may not be the optimum way to start a therapy session. This client may respond better to a more physical induction process, or even a rapid induction, such as hand drop or magnetic hands…
The assessment process will help the hypnotherapist gain information both on the preferred style (permissive or authoritarian) and the client’s strongest modality / sense (e.g. visual, auditory or kinaesthetic). However, it will also give you other clear indications of the client’s ability to follow and respond to suggestions, and it will let you know whether the client’s imagination is linked to their ability to make physical movements.
As well as a great information-gathering tool, it can be a great ‘warm up’ for the client. It will help them to engage their focus, concentration and imagination and get feedback prior to the formal hypnosis and therapy aspects of the session. Furthermore, where a client may have some performance anxiety, perhaps wondering “Will I even be able to ‘do’ hypnosis?” then it can be a great way to ease them into hypnosis, build their confidence and further dispel any myths and misconceptions. This leads into another benefit, that of acting as a ‘convincer’ to the client. Demonstrating, to the client, the power of their mind in response to suggestion. This is further empowering and confidence-building for the client.
What are your ‘go to’ hypnotic suggestibility tests? How many suggestibility tests can you name? Perhaps you know magnetic fingers, magnetic hands, bucket and balloon, Chevreul’s pendulum, falling-back / postural sway, hand-lock/hand-clasp, Creative Imagination Scale, eye lock… and there are many more. Certainly, you could simply suggest a specific type of phenomena (such as catalepsy) outside of the hypnosis process and assess the individual’s level of response.
Generally, suggestibility tests are relatively quick and simple. More comprehensive tests, such as the Stanford Hypnotic Susceptibility Scale (SHSS) and the Harvard Group Scale of Hypnotic Susceptibility (HGSHS) are popular with researchers. The Stanford Scale is a fully scripted test, and tests are worked through in order, until the individual is not able to perform the relevant test. The Harvard Scale offers a range of tests, and then participants self-report their responses. Individuals (‘subjects’) are then generally categorised into low, medium or high responders. Within research, interventions are then conducted and assessed in relation to hypnotic suggestibility levels. This can provide interesting insights for the hypnotherapy practitioner. For example, although some therapists might consider there is a need for someone to be highly suggestible to obtain effective hypnotic pain management, Leonard Milling reports that there is compelling evidence for effective analgesia for both those in the high and medium ranges of hypnotic suggestibility. A 2016 paper used the Harvard Group Scale of Hypnotic Suggestibility on 50 participants and found that there was a relationship between hypnotic suggestibility and placebo response, particularly in relation to relaxation (a placebo sedative was employed).
In addition to research on what may be influenced by hypnotic suggestibility, research is also conducted on what factors may influence hypnotic suggestibility. Recent research, published in 2013, found that oxytocin can increase hypnotic suggestibility. As good rapport can increase natural production of oxytocin, there is perhaps an argument that individuals will perform better in suggestibility tests where there is rapport with the hypnotist, rather than where there isn’t. Many different elements can influence suggestibility as can be seen with a 2015 study which found that LSD (Lysergic acid diethylamide), which has been used in psychotherapeutic support of treatment of mood disorders and addiction, enhances suggestibility (Barber’s Creative Imagination Scale) in healthy individuals. However, perhaps the hypnotherapist may find rapport a more accessible (and legal) influencing option!
So, are suggestibility tests just for street and stage hypnotists? Perhaps not. There are clearly many benefits for hypnosis researchers and for hypnotherapists helping hypnotherapy clients achieve their best possible outcomes. If you’d like to learn more about suggestibility testing, do get in touch, we’re happy to point you in the right direction! We hope this blog has been helpful, and if you have any questions relating to this blog, do please get in touch, because we’re always happy to help!
References & further reading
Bryant, R. A., & Hung, L. (2013). Oxytocin enhances social persuasion during hypnosis. PloS one, 8(4), e60711.
Carhart-Harris, R. L., Kaelen, M., Whalley, M. G., Bolstridge, M., Feilding, A., & Nutt, D. J. (2015). LSD enhances suggestibility in healthy volunteers. Psychopharmacology, 232(4), 785-794.
Milling, L. S. (2008). Is high hypnotic suggestibility necessary for successful hypnotic pain intervention?. Current pain and headache reports, 12(2), 98.
Sheiner, E. O., Lifshitz, M., & Raz, A. (2016). Placebo response correlates with hypnotic suggestibility. Psychology of Consciousness: Theory, Research, and Practice, 3(2), 146.
Woody, E. Z., Barnier, A. J., & McConkey, K. M. (2005). Multiple Hypnotizabilities: Differentiating the Building Blocks of Hypnotic Response. Psychological Assessment, 17(2), 200-211.
– written by Dr Kate Beaven-Marks