Overview — what “hypnosis susceptibility” tests measure
These tests assess how responsive a person is to hypnotic suggestions (i.e., capacity to enter hypnotic states and to experience suggested changes in perception, memory, motor control, or involuntariness).
They differ by format (individual vs. group), focus (auditory/motor/ideomotor/imagery/anaesthesia/age regression/arm levitation/sensory alteration), length, and scoring method (number of suggestions accepted or objective behavioral criteria).
No test is a perfect measure of a unitary trait; responsiveness can vary with context, rapport, expectation, wording of suggestions, and the administrator’s skill.
Common, established scales
Stanford Hypnotic Susceptibility Scales — Forms A, B, and C (SHSS:A, SHSS:B, SHSS:C)
Format: Individual, standard clinical/research administration; about 12–15 suggestions (often 12).
Typical suggestions include: eye closure, hand lowering, arm levitation, hand levitation/lock, arm rigidity, sensory alterations (taste/weight change), amnesia for a suggested item, hallucinations (e.g., glove anesthesia or hallucinated odor), post-hypnotic suggestions and amnesia for suggestions.
Scoring: Each suggestion scored pass/fail (1/0) by objective behavioral criteria. Total score 0–12 (or up to 15 depending on form).
Advantages: Best-known, high reliability and validity, widely used for research; covers a range of motor, sensory, and cognitive suggestions.
Limitations: Time-consuming, requires trained administrator and quiet one-to-one setting.
Harvard Group Scale of Hypnotic Susceptibility — Form A (HGSHS:A)
Format: Group administration (classroom-like), typically 12 suggested items delivered via tape or script.
Typical items: Eye closure, arm heaviness, finger lock, visual hallucination, anosmia/age regression items adapted for group use.
Scoring: Binary pass/fail per item; group norms available.
Advantages: Efficient for screening many people quickly; good for large studies.
Limitations: Less detailed than individual scales; some items must be modified to work in a group. Lower sensitivity for high and low ends than SHSS.
Waterloo-Stanford Group Scale (WSGC)
Format: Group, often used for children/adolescents; items tailored for age.
Advantages: Efficient for educational settings.
Limitations: Fewer established psychometric norms compared with SHSS.
Creative Imagination Scale (CIS)
Format: Self-report measure; participant rates their own experience of suggested items.
Uses: Quick screening, particularly where behavioral scoring is impractical.
Limitations: Relies on subjective report; more susceptible to demand characteristics.
Barber Suggestibility Scale (BSS)
Format: Shorter, individual scale focusing on compliance-based suggestibility rather than hypnotic induction per se.
Notes: Emphasizes personality and compliance components.
Format: Shorter clinical measure focusing on depth of trance using objective signs (eye roll, etc.) and a few test suggestions.
Uses: Quick clinical depth assessment rather than full suggestibility profiling.
Purpose and focus: A short suggestibility task designed to measure sensory/olfactory hallucination-type response, plus openness to suggestion; often used as a quick screening item or as part of a battery.
Typical procedure:
Induction: brief relaxation/hypnotic induction (varies by administrator; may be as short as a focused attention induction).
Suggestion: Participant is told they will smell a lemon (or that a lemon has been placed nearby) and then the hypnotist suggests they can clearly smell and maybe taste lemon juice, describe its scent, and perhaps experience a puckering sensation.
Variants: Some versions include the participant actually being handed a lemon or asked to imagine one. The suggestion can emphasize vivid, automatic experience (olfactory, gustatory, mouth puckering).
Scoring:
Subjective self-report of smelling/tasting lemon.
Behavioral indicators such as facial expression (puckering), salivation, or verbal description.
Some structured forms ask specific questions (Did you smell lemon? Rate intensity 0–5; did mouth pucker?).
Strengths:
Simple, short, easy to include in a battery.
Tests sensory and gustatory suggestion and capacity for vivid imagery/hallucination.
Limitations:
Susceptible to demand characteristics (participant may report smelling because they think it’s expected).
Single-item measures capture only one domain; should be interpreted alongside other items.
Cultural/expectation effects (lemon familiarity, explicit cues) can influence results.
Practical notes:
For better objectivity, record facial signs (puckering) and salivation; ask sensory-rating scales rather than yes/no.
Best used as part of a multi-item battery, not as sole measure of hypnotizability.
Kappasinian Suggestibility Test
Note: The Kappasinian test is less familiar in mainstream research literature than SHSS or Harvard scales; descriptions vary across sources.
Purpose and focus: A structured suggestibility test focused on layered suggestions (progressive complexity) to gauge depth and breadth of responsiveness, often including motor, sensory, and post-hypnotic elements.
Typical procedure:
Pre-induction briefing: brief explanation and consent; neutral expectations to reduce compliance bias.
Induction: standardized induction script (progressive relaxation, focused attention).
Test items: A sequence of suggestions increasing in complexity. Items often include:
Eye closure and heaviness (basic compliance).
Arm levitation/float (ideomotor).
Motor inhibition (hand lock).
Sensory alteration (e.g., lemon smell/taste, numbness).
Hallucination (visual or auditory).
Post-hypnotic suggestion and subsequent amnesia for it.
Scoring: Objective pass/fail for each item, sometimes with graded levels (none/partial/full). Composite score and categorical classification (low/medium/high) commonly used.
Strengths:
Structured progression allows assessment of response pattern (e.g., strong motor but weak sensory responsiveness).
Useful for both clinical screening and research if standardized carefully.
Limitations:
Because it’s less standardized in published literature, norms may be limited and psychometric properties less established than SHSS or HGSHS.
Requires a consistent script and clear behavioral scoring criteria to be reliable.
Practical notes:
If using the Kappasinian test clinically or in research, develop and pilot a clear scoring rubric, and combine it with a validated scale for triangulation.
Report administration details (exact script, induction length) so others can interpret and compare results.
Other specific item examples and what they measure
Eye closure/hand lowering: simple behavioral signs of absorption/relaxation; often early items to create rapport and screen for basic responsiveness.
Arm levitation (ideomotor): measures involuntary movement response to suggestion; often early, easier pass for many subjects.
Arm immobilization/lock: tests ability to experience motor inhibition and sense of involuntariness; correlated with deeper suggestibility.
Anesthesia/glove anesthesia: tests suggestion-induced sensory anesthesia (tactile) and can demonstrate strong sensory-cognitive integration.
Hallucinations (olfactory, taste, visual): measure capacity for suggested perceptual experience—useful diagnostically because hallucination items often discriminate higher from moderate suggestibility.
Post-hypnotic suggestion and amnesia: tests whether a suggestion given in hypnosis can affect later behavior and memory; sensitive to deeper responsiveness and to expectation/demand.
Age regression and time distortion: higher-complexity cognitive suggestions about memory/identity; useful clinically but more variable.
Scoring and interpretation
Binary scoring (1 = observable/credible response; 0 = no response) is most common and objective.
Some researchers use graded scoring (0–2 or 0–3) to capture partial responses.
Norms: For established scales like SHSS and HGSHS, normative distributions exist (e.g., many people cluster in low-moderate; very highly hypnotizable individuals are a minority).
Typical cutoffs: Often defined as low (0–3), medium (4–8), high (9–12) on a 12-item scale — adjust by scale used.
Use caution: Don’t equate a low test score with inability to benefit from hypnotic techniques clinically—context, motivation, rapport and tailored suggestions matter.
Practical guidance for choosing and using a test
For research needing validated, comparable results: use SHSS (individual) or HGSHS (group) with published norms.
For clinical screening where time is limited: short tests (Lemon Test as part of a brief sensory battery, HIP, or short-item scales) can help, but interpret cautiously.
For groups: use the Harvard Group scale or Waterloo-Stanford Group scale.
Combine multiple domains: motor, sensory, cognitive, and post-hypnotic items to better profile an individual’s pattern of suggestibility.
Reduce demand bias: use neutral language, avoid leading cues, and record behavioral indicators where possible.
Train administrators: consistent wording, pacing, and behavioral scoring rules improve reliability.