Hypnotherapy: a clinically evidenced method for changing mental states

Learning Objectives

• Define hypnosis according to current scientific consensus and distinguish it from stage and popular myths.
• Trace how scientific views on the nature of hypnosis have evolved — from "animal magnetism" to brain-imaging research.
• Explain what modern neuroscience knows about the brain mechanisms of the hypnotic state and about individual hypnotizability.
• Evaluate the evidence base for hypnotherapy in anxiety, pain, irritable bowel syndrome, preparation for medical procedures, and other conditions, based on current meta-analyses.
• Describe how a hypnotherapy session unfolds and what techniques practitioners use.
• Distinguish well-supported applications of hypnotherapy from risky practices, particularly those related to memory "recovery."
• Formulate criteria for choosing a qualified hypnotherapist and understand the method's contraindications.

Introduction

Say the word "hypnosis" and most people immediately picture a stage performer making an audience member cluck like a chicken, or a sinister figure controlling someone else's will with a snap of the fingers. This cultural legacy is so powerful that even today it overshadows a very different, far less dramatic, but much better-documented reality: hypnosis is a measurable, reproducible psychophysiological phenomenon studied seriously in laboratories at Stanford, Harvard, and dozens of other universities, and hypnotherapy is increasingly included in evidence-based clinical protocols alongside cognitive behavioral therapy.

At the same time, it would be a mistake to swing to the opposite extreme and treat hypnotherapy as a universal, almost magical tool. The science of hypnosis has long been — and to some extent remains — an arena of sharp debate. Researchers have argued over whether hypnosis is a distinct state of consciousness or simply a form of heightened suggestibility and social readiness to meet expectations. This article attempts to present a balanced, up-to-date picture: what modern science reliably knows about hypnosis, where the evidence is strong, where it is still preliminary, and where popular beliefs plainly diverge from the facts.

From "Animal Magnetism" to Evidence-Based Medicine: A Brief History of Hypnosis

The scientific study of hypnosis began with a mistake. In the 1770s, the German physician Franz Anton Mesmer claimed to cure patients using an invisible "magnetic fluid" that a healer could redistribute through the body with the hands. The effects were real — people fell into trance-like states and experienced symptom relief — but when a French royal commission (which included, among others, Benjamin Franklin) investigated the method in 1784, it concluded that no "magnetism" existed and that all the effects were explained by imagination and suggestion. This was, in effect, one of the first controlled experiments in the history of medicine, and it immediately pointed to the key question that has followed hypnosis ever since: where does the genuine physiological process end and the power of expectation begin?

In the 1840s, the Scottish surgeon James Braid abandoned Mesmer's mystical terminology and coined the term "hypnotism" (from the Greek hypnos, sleep), though he later admitted the name was misleading, since the state he observed was not actually sleep. In the late nineteenth century, the neurologist Jean-Martin Charcot studied hypnosis at the Salpêtrière hospital in Paris, linking it primarily to hysteria, while his contemporaries Hippolyte Bernheim and Ambroise-Auguste Liébeault argued that hypnotizability was a normal psychological trait rather than a sign of pathology. A young Sigmund Freud used hypnosis in clinical practice for a time before eventually abandoning it in favor of free association.

The true clinical renaissance of hypnotherapy is associated with the American psychiatrist Milton Erickson, who in the mid-twentieth century developed a gentle, non-directive style of suggestion tailored to each individual patient — an approach that still underlies most schools of clinical hypnotherapy today. In parallel, the psychologist Ernest Hilgard formulated neodissociation theory in the 1970s, proposing that hypnosis splits the stream of consciousness into parallel "channels" (his famous "hidden observer" experiments), while Theodore Barber and Nicholas Spanos championed the opposing sociocognitive position: hypnotic phenomena are explained by ordinary psychological processes — imagination, motivation, expectation, and willingness to play a social role — rather than by a special state of consciousness.

This "state versus non-state" debate shaped the science of hypnosis for decades. A turning point came in the twenty-first century, when functional neuroimaging methods made it possible to observe the brain directly during hypnosis — revealing entirely real, measurable changes in brain activity that are difficult to explain by social role-playing alone. In 2014–2015, a working group led by Gary Elkins, Arreed Barabasz, James Council, and David Spiegel revised the official definition of hypnosis issued by the American Psychological Association's Society of Psychological Hypnosis (APA Division 30), cementing the field's modern understanding of the term.

What Hypnosis Is, According to Modern Science

According to the revised APA Division 30 definition, hypnosis is "a state of consciousness involving focused attention and reduced peripheral awareness characterized by an enhanced capacity for response to suggestion." This definition is deliberately cautious: it describes hypnosis through observable characteristics (attention, suggestibility) rather than through metaphysical claims about "trance" or the "subconscious."

The State-Versus-Non-State Debate: A Modern Synthesis

The classic dispute between proponents of a distinct "altered state" and proponents of a purely sociocognitive explanation has largely given way today to a more integrative view. The psychologist Irving Kirsch once described hypnosis as a "non-deceptive placebo" — an open application of suggestion whose effectiveness is tied to patient expectation as much as to the technique itself. This remains an important part of the picture: expectation, motivation, and the therapeutic relationship genuinely shape outcomes to a significant degree. At the same time, neuroimaging research over the past decade shows that during deep hypnosis, quite specific and measurable changes occur in the brain that cannot be reduced to mere "performing for an audience." The modern consensus acknowledges both components: hypnosis is not a mystical "third state of consciousness," but neither is it simply polite compliance with a role; it is a real, measurable pattern of brain activity that is triggered and sustained by social-psychological factors — suggestion, expectation, and trust in the therapist.

What Neuroimaging Shows

A study by David Spiegel's team at Stanford University, published in 2016–2017 in the journal Cerebral Cortex, scanned the brains of 57 participants during hypnosis and identified three consistent changes in highly hypnotizable individuals:

• Decreased activity in the dorsal anterior cingulate cortex, part of the brain's salience network, which is responsible for detecting threats and monitoring potential concerns. This aligns with the subjective sense of deep absorption without excessive worry.
• Increased functional connectivity between the dorsolateral prefrontal cortex and the insula, regions involved in processing bodily sensations. This may explain enhanced control over physiological responses, including pain.
• Weakened connectivity between the dorsolateral prefrontal cortex and the default mode network, a network associated with self-reflection. Researchers interpret this as a temporary "disconnect" between action and habitual self-awareness, allowing a person to carry out suggested actions without a constant internal commentary of "am I really doing this."

"In hypnosis, you're so absorbed that you're not worrying about anything else," is how Spiegel described the phenomenon. An earlier study by the same group (Hoeft and colleagues, 2012) found that an individual's degree of hypnotizability correlates with stable patterns of connectivity between the anterior cingulate cortex and the dorsolateral prefrontal cortex — suggesting that hypnotizability appears to have a recognizable neurobiological basis rather than being simply a personality trait or willingness to "play along."

Hypnotizability: Why Some People Respond More Readily Than Others

Hypnotizability is a stable, individually variable trait that remains relatively consistent across the lifespan. Most people show moderate hypnotizability, roughly one person in ten is highly hypnotizable, and a similar proportion shows low responsiveness to suggestion. The psychologist Deirdre Barrett identified two distinct subtypes among highly hypnotizable individuals in her research: "fantasizers" — people with vivid imaginations and a lifelong tendency toward absorbed daydreaming — and "dissociaters," people who often have a history of psychological trauma and learned to "switch off" distressing experiences through dissociation. This is an important observation: high hypnotizability is neither a talent nor a flaw in itself, and a therapist should take into account which type of patient they are working with, especially when trauma history is involved.

Hypnotherapy in Action: What the Research Actually Shows

One of the most thorough recent reviews is the meta-analytic review by Rosendahl and colleagues (2024), which covered 49 meta-analyses and 261 randomized controlled trials published after 2000, spanning pain, medical procedures, childbirth, irritable bowel syndrome (IBS), oncology, smoking cessation, obesity, and mental disorders. Effect sizes (Cohen's d) ranged from −0.04 to 2.72; 63.6% of the reported effects were statistically significant, 28.8% were large, and a further 25.4% were medium in size. The strongest and most consistent effects were found for pediatric needle procedures and preparation for medical interventions in general.

Pain. Systematic reviews and meta-analyses from 2024–2025 (including work published in PAIN Reports and a review in the Journal of Clinical Medicine) confirm medium-to-large effects for acute procedural pain and chronic pain conditions, including musculoskeletal and neuropathic pain. Here, hypnosis functions as an adjunct rather than a replacement for analgesia, and it is best studied in that role.

Irritable Bowel Syndrome. Gut-directed hypnotherapy is one of the most robustly evidence-supported applications of the method. Meta-analyses from 2024–2025 show consistent symptom reduction and improved quality of life for patients. The UK's National Institute for Health and Care Excellence (NICE) lists hypnotherapy alongside cognitive behavioral therapy as one of the psychological approaches for IBS patients who have not responded to first-line treatment — though the review authors themselves note that the quality of the underlying studies is often modest and calls for better-designed trials.

Anxiety. A meta-analysis by Valentine, Milling, and colleagues (2019, International Journal of Clinical and Experimental Hypnosis) found a moderate-to-large effect of hypnosis in reducing anxiety, particularly when hypnosis is combined with other interventions, such as CBT, rather than used in isolation.

Depression. Data on combining hypnosis with CBT (so-called "hypno-CBT") suggest that in some studies the combined approach performs no worse than CBT alone, and in certain cases produces faster symptom relief. This is a promising but still less mature evidence base compared with pain or IBS.

Other applications. Moderate evidence exists for pre-surgical and pre-dental procedure anxiety, menopausal hot flashes (the method is endorsed by the North American Menopause Society, though the society itself cautions that favorable evidence remains limited), and childbirth preparation. Evidence on smoking cessation and obesity treatment is conflicting and does not yet support confidently recommending hypnosis as a standalone method for these goals.

It is worth emphasizing: no authoritative organization describes hypnotherapy as a panacea. The U.S. National Center for Complementary and Integrative Health (NCCIH) characterizes most of the evidence as "promising but not conclusive" and stresses the need for higher-quality research across nearly every application listed above.

How a Hypnotherapy Session Unfolds

A typical clinical hypnotherapy session consists of several sequential stages. It begins with a preliminary conversation, in which the therapist clarifies the patient's goals, expectations, and any possible contraindications. This is followed by induction — a structured process that helps the person shift into a state of focused attention and relaxation: this might involve gaze fixation, counting, progressive muscle relaxation, or guided imagery. After induction, the therapist deepens the state and moves into the main, therapeutic part of the session — the actual suggestions aimed at a specific goal: changing pain perception, reprocessing an emotional reaction to a trigger, building a new habit, or strengthening motivation for change. The session ends with a gradual "return" from the trance and a brief discussion.

A session typically lasts 45–90 minutes, and a course of treatment ranges from a few sessions to 10–12, depending on the presenting issue; most gut-directed hypnotherapy protocols for IBS, for example, run for roughly seven sessions. Modern practice actively combines hypnosis with other evidence-based approaches — most notably cognitive behavioral therapy — and teaches patients self-hypnosis techniques for independent use between sessions. Sessions are increasingly conducted remotely as well, which, based on available data, does not substantially reduce effectiveness for most indications.

Limitations, Myths, and a Critical Perspective

A balanced, modern view of hypnotherapy necessarily includes its limitations — and here science departs from popular belief in both directions: some things people believe are exaggerated, and some things that seem "obvious" are actually risky.

The myth of losing control. The most common fear is that a hypnotized person completely loses their will and will carry out any command. Researchers studying stage hypnosis show that dramatic acts like "clucking like a chicken" are explained not by loss of control but by a combination of careful selection of highly suggestible participants, the social pressure of the stage, audience expectations, and the performer's own showmanship. In clinical practice, a person remains conscious, remembers the session, and will not carry out a suggestion that conflicts with their values or safety.

The myth of "special" people. Hypnotizability is a continuum, not a division between those who "can be hypnotized" and those who cannot: the vast majority of people are able to reach some level of hypnotic state, and the depth of trance affects the intensity of the effect more than whether a person can benefit from the therapy at all.

The risk of false memories — and this is not a myth. Here, modern science is, in fact, far more cautious than popular culture. Using hypnosis to "recover" repressed or forgotten memories — so-called regression — remains a highly controversial practice. Research shows that a state of heightened suggestibility can contribute to the formation of false memories, which a person subsequently experiences as entirely genuine. The American Medical Association and the American Psychological Association explicitly warn that, without independent corroboration, it is impossible to distinguish a memory obtained under hypnosis from a false one. So-called "past-life regression" is regarded by the scientific community as pseudoscience. A qualified hypnotherapist does not use hypnosis to "excavate" childhood traumatic events as an end in itself, and handles any memories that surface during a session with great caution.

Scientific criticism and skepticism. Some researchers — notably Steven Jay Lynn, Irving Kirsch, and Scott Lilienfeld — continue to argue that much of the "hypnotic" effect can be reproduced without formal induction, through suggestion and expectation alone, and that the status of hypnosis as a distinct state remains a matter of scientific debate. This does not negate the clinical usefulness of the method, but it is an important reminder: hypnotherapy works not through some mystical power, but through entirely comprehensible psychological and neurophysiological mechanisms, and clinical effectiveness does not require a final answer to the question of whether hypnosis is a separate state of consciousness.

Contraindications. Hypnotherapy is generally considered a safe method with a minimal side-effect profile, but it has limits: it is not used during active psychosis or severe personality disorders outside specialized care, and in cases of dissociative disorders (where hypnotizability tends to be highest among all clinical groups), the work requires a therapist specifically trained in trauma-informed approaches.

Choosing a Hypnotherapist and Knowing When to Seek One Out

Hypnotherapy may be appropriate for anxiety and depressive disorders, chronic stress and burnout, specific phobias and panic attacks, psychosomatic complaints, preparation for medical procedures and childbirth, and as a supportive method for PTSD — provided the work is done with a practitioner trained in trauma-oriented protocols.

A key practical criterion is baseline training: evidence-based hypnotherapy is delivered by practitioners with a medical or psychological education who have completed dedicated, certified training in clinical hypnosis, not short commercial courses without a clinical foundation. It's worth being wary if a practitioner promises a guaranteed result after a single session, presents "excavating" traumatic memories as a mandatory first step, or positions hypnosis as a replacement for necessary medication or psychiatric treatment rather than a complement to it.

Measuring Effectiveness and Applying the Method in Practice

In research settings, the effectiveness of hypnotherapy is assessed through randomized controlled trials with active control groups (rather than comparisons against "no treatment," which inflates the apparent effect), standardized hypnotizability scales (such as the Stanford Scale), and objective physiological and neuroimaging markers. In clinical practice, progress is tracked through changes in symptoms — anxiety levels, pain intensity, frequency of IBS symptoms — using standard questionnaires administered before and after the course of treatment.

For someone considering hypnotherapy, some practical guidelines are worth keeping in mind:

• Choose a practitioner with verified medical or psychological credentials and specialized certification in clinical hypnosis.
• Treat hypnotherapy as a complement to evidence-based treatment (CBT, medication where needed), not a replacement for it.
• Set realistic expectations: the strongest evidence exists for pain, procedure preparation, and IBS; for other conditions the effect is often moderate and depends on combination with other methods.
• Be cautious of any promises to "recover" repressed memories, and avoid practitioners who offer this as a primary method of work.
• Give the method a fair trial period — a typical course involves several sessions, not just one.

Conclusion

The modern scientific view of hypnosis differs substantially both from the stage myth of "controlling someone else's will" and from the marketing image of a "magic pill" for every psychological problem. Hypnosis is a measurable, reproducible psychophysiological phenomenon with identifiable neural correlates, and hypnotherapy is an evidence-supported — though unevenly so across different conditions — psychotherapy tool, strongest in managing pain, preparing for medical procedures, and treating irritable bowel syndrome, and still less conclusive for anxiety, depression, or breaking harmful habits. Understanding these boundaries is not a reason to dismiss the method, but a necessary condition for using it responsibly and safely: hypnotherapy works best when delivered by a qualified practitioner as part of a broader, evidence-based plan of care, rather than as an isolated miracle cure.

Outside Resources

• Elkins, G. R., Barabasz, A. F., Council, J. R., & Spiegel, D. (2015). Advancing Research and Practice: The Revised APA Division 30 Definition of Hypnosis. American Journal of Clinical Hypnosis — the official current definition of hypnosis.
• Rosendahl, J., Alldredge, C. T., & Haddenhorst, A. (2024). Meta-analytic evidence on the efficacy of hypnosis for mental and somatic health issues: a 20-year perspective. Frontiers in Psychology — the most comprehensive review of the evidence base as of the mid-2020s.
• NCCIH (National Center for Complementary and Integrative Health), Hypnosis — an official evidence overview for various conditions, written for a general audience.
• APA Monitor on Psychology (2024), Uncovering the new science of clinical hypnosis — a popular account of current neuroscience research on hypnosis.
• Jiang, H., White, M. P., Greicius, M. D., Waelde, L. C., & Spiegel, D. (2017). Brain Activity and Functional Connectivity Associated with Hypnosis. Cerebral Cortex — the key Stanford University neuroimaging study.
• Barrett, D. (1992). Fantasizers and dissociaters: data on two distinct subgroups of deep trance subjects. Psychological Reports.

Discussion Questions

• Why was the "hypnosis as a distinct state of consciousness versus hypnosis as a sociocognitive phenomenon" debate long considered unresolvable — and what did neuroimaging research change?
• How would you explain the difference between stage and clinical hypnosis to someone who is afraid of "losing control" during a session?
• Why is the evidence for hypnotherapy's effectiveness considerably stronger for procedural pain and IBS than, say, for smoking cessation? What methodological factors in the research might explain this?
• What makes the practice of "recovering memories" under hypnosis risky even when both the therapist and the patient act with good intentions?
• How might the concept of hypnotizability as a stable trait (rather than a "skill" or a "weakness") change the way people think about their own response to attempts at hypnosis?
• Why does it matter that hypnotherapy be delivered by a practitioner with medical or psychological training rather than simply a certified "hypnotist" without clinical education?
• In your view, what ethical boundaries should exist for the use of hypnosis outside a clinical context — for example, in entertainment shows?

Vocabulary

Default mode network — a network of brain regions active during rest and self-reflection, whose connectivity with the prefrontal cortex weakens during deep hypnosis.

Dissociation — a psychological process involving partial or complete disconnection of certain mental functions (memory, identity, perception) from the rest of conscious experience.

False memory — a memory of an event that either never happened or occurred differently, subjectively experienced by the person as accurate.

Gut-directed hypnotherapy — a hypnotherapy protocol specifically developed to reduce symptoms of irritable bowel syndrome through suggestions aimed at regulating bowel function.

Hypnosis — as defined by APA Division 30 (2015), a state of consciousness involving focused attention and reduced peripheral awareness, characterized by an enhanced capacity to respond to suggestion.

Hypnotherapy — the therapeutic application of hypnosis to achieve psychological or medical goals: reducing anxiety, managing pain, changing behavioral patterns, and more.

Hypnotizability — a stable, individual trait that determines how responsive a person is to hypnotic suggestion; distributed across the population along something close to a normal curve.

Induction — a structured procedure that helps a person shift into a state of focused attention and relaxation at the start of a hypnotherapy session.

Neodissociation theory — Ernest Hilgard's theory proposing that hypnosis splits the stream of consciousness into parallel "channels" of information processing.

Regression (age or past-life) — a controversial and scientifically unsupported practice of using hypnosis to "recover" early or past memories; associated with a high risk of forming false memories.

Salience network — a brain network responsible for detecting and prioritizing significant internal and external stimuli, including potential threats.

Self-hypnosis — a technique for independently inducing a state of focused attention and suggestion without a therapist present, taught as part of a hypnotherapy course.

Sociocognitive theory of hypnosis — a theoretical approach (Barber, Spanos) holding that hypnotic phenomena are explained by ordinary psychological processes — imagination, motivation, expectation, and social role — rather than by a special state of consciousness.

Suggestion — a communicative influence aimed at changing perception, thoughts, emotions, or behavior without direct rational persuasion.

Sources and Recommended Reading

• Elkins, G. R., Barabasz, A. F., Council, J. R., & Spiegel, D. Advancing Research and Practice: The Revised APA Division 30 Definition of Hypnosis. American Journal of Clinical Hypnosis, 57(4), 2015, 378–385.
• Rosendahl, J., Alldredge, C. T., & Haddenhorst, A. Meta-analytic evidence on the efficacy of hypnosis for mental and somatic health issues: a 20-year perspective. Frontiers in Psychology, 2024.
• Valentine, K. E., Milling, L. S., Clark, L. J., & Moriarty, C. L. The Efficacy of Hypnosis as a Treatment for Anxiety: A Meta-Analysis. International Journal of Clinical and Experimental Hypnosis, 67(3), 2019, 336–363.
• Jiang, H., White, M. P., Greicius, M. D., Waelde, L. C., & Spiegel, D. Brain Activity and Functional Connectivity Associated with Hypnosis. Cerebral Cortex, 27(8), 2017, 4083–4093.
• Hoeft, F., Gabrieli, J. D. E., Whitfield-Gabrieli, S., et al. Functional Brain Basis of Hypnotizability. Archives of General Psychiatry, 69(10), 2012, 1064–1072.
• Barrett, D. Fantasizers and dissociaters: data on two distinct subgroups of deep trance subjects. Psychological Reports, 71(3), 1992, 1011–1014.
• Kirsch, I. Response expectancy as a determinant of experience and behavior. American Psychologist, 40, 1985, 1189–1202.
• NCCIH (National Center for Complementary and Integrative Health). Hypnosis. U.S. National Institutes of Health, 2024.
• National Institute for Health and Care Excellence (NICE). Irritable Bowel Syndrome in Adults: Diagnosis and Management, updated guideline.