Moving beyond the concept of suggestibility:hypnotic ability, its relevance, and assessment in clinical practice

Hypnotizability, that is, the capacity to experience a transition into a hypnotic state and perform hypnotic tasks, has a wide range of degrees, from not being hypnotizable at all to being able to respond with intriguing and even surprising intensity to hypnotic instructions.The level of hypnotizability may be assessed with several scales. In general, any scale closely depends on its construct, which, however accurate it may be, is likely to be only a partial description of the observed phenomenon; therefore, one can expect that the accuracy of available hypnotizability scales, despite their being useful and reliable, may be less than optimal yet.The Stanford and Harvard scales, although effective, are mainly based on the construct of suggestibility and, are not suitable for use in patients, thus yielding an unbridgeable gap between clinical hypnosis and research. Furthermore, most scales take longer to administer than the clinical interventions being performed.The Stanford Hypnotic Clinical Scale (SHCS) is a shorter version of the Stanford Hypnotic Susceptibility Scale (SHSS) introduced for use with patients, but takes about 25-30 min (Morgan & Hilgard, 1978), a time still hardly compatible with the clinical setting, especially in surgical specialties.The Hypnotic Induction Profile (HIP), introduced by Spiegel (Spiegel, 1977; Spiegel & Spiegel, 2004) calls for Only 5-10 mi and is significant correlated to both the SHSS and SHCS (Frishholz et al., 1981; Gritzalis et al., 2009), making it the fastest and most manageable scale to be used with clinical patients. Furthermore, it is significantly related to the Dissociative Experiences Scale (DES) and the Interpersonal Reactivity Index (IRI)-c subscale. It is worth noting that the DES and the Tellegen Absorption Scale (TAS) are significantly correlated to each other, showing that absorption implies dissociation as its component, leadingto what is outside the field of attention being not perceived.While no evidence supports a specific role of suggestibility in hypnosis, the following personality features aresignificantly related to the HIP: a) stronger perception of the inner world, b) decreased aptitude for managing memory processing, and c) increased sensitivity and empathy (Facco et al., 2017). Further potentially relevant aspects of hypnotizability may include cognitive and emotional flexibility and openness to experiences (study in progress).The HIP has been tested in thousands of patients and shows a good interrater reliability and reproducibility across time and Countries. It checks both behavioral and subjective components of hypnosis and it is more sensitive than other scales to psychiatric disorders, providing a fast, manageable, and reliable estimate of hypnotic ability, allowing one to predict the outcome of hypnotic treatment in individual patients both in psychology and in medicine.