© Tara Winstead
What exactly happens in the brain during hypnosis and why is still not fully understood.
March 4, 2024
Margit Hiebl
How does medical hypnosis work? Discover how it affects the brain, its medical uses, and possible risks
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Serious hypnosis is one of the oldest healing methods. First indications can be found in Babylonian cuneiform. But it is not until the mid-20th century that it is also scientifically recognized—a major achievement of the American psychiatrist Milton H. Erickson , who developed it into an experiential approach to solving problems.
Meanwhile, hypnotherapy is a well-researched psychotherapeutic method with a variety of applications. This includes the treatment of anxiety, depression , traumatic experiences, addiction, sleep disorders or burnout. Even in the medical context, there is a wide range of applications – from psychosomatic disorders to acute pain during surgical procedures, in childbirth preparation, and for anxiety or pain control in dental care.
What exactly happens in the brain during hypnosis and why is still not fully researched. However, measurements and imaging techniques show that something happens and where: The areas where fear or pain are processed are less to not active. Brainwave measurements show that pain stimuli are indeed transmitted but apparently processed differently.
Areas responsible for emotions and imagination, however, are as active as if one were actually experiencing something. Physiologically, it shows that heartbeat and breathing slow down, blood pressure decreases. On a mental level, intense calm and balance are achieved. Internal images, memories, and feelings are experienced more intensely, noises or other disturbing perceptions can be more easily blocked out, and even distressing experiences can be distanced from.
This special state of consciousness is achieved in hypnosis through a so-called induction. “It begins with instructions to focus attention and direct it more inward,” explains psychologist and psychotherapist Norbert Loth. Psychotherapist Norbert Loth from Munich, founding member and lecturer of the German Society for Hypnosis and Hypnotherapy and the Milton Erickson Society.
“These are usually relaxation instructions that lead to consciousness withdrawing more from activity.” This is also called trance – or, more precisely, because it is initiated as part of the therapeutic process, a hypnotically altered state of consciousness or hypnotic trance. “Many experience this as the pleasant state just before falling asleep, when one tends to think in images.”
Most people are capable of this. And sometimes our brain can even do it on its own. For example, in emergency situations or when Daydreaming. Here, the inner autopilot takes over.
More precisely: The so-called "Default Mode Network," a resting-state network of brain regions activated during inactivity. "In hypnosis, it helps us initiate processing or discard the unimportant to focus on the intended goal of therapy," says Norbert Loth.
In the further course of psychotherapeutic treatment, the focus is on the question: What does a person need to better deal with a problem? Similar experiences or situations from the past are searched for that have already conveyed calmness or security.
A valuable resource from which to draw again in the hypnotic state through suggestions. In case of exam anxiety, perhaps a previously successful exam is replayed: step by step, the preparation, the smooth process, and the great joy afterward. If there is nothing strong enough in one's own experience, superheroes, power animals, or magical beings can be introduced to help overcome the problem.
The search for the right resource can also lead to the future. "So the story can continue on the topic of Depression be: What if the depression is gone? How do I live my life? What has changed?" So the right story is key to success. It is not always found immediately. Accordingly, hypnotherapy can take between 20 and 60 sessions.
Hypnosis works, but not always with the desired result. “These people may find it difficult with hypnosis, resist, have fears. Then the therapist has to deal with this first before, for example, addressing smoking cessation,” says Loth.
“Also, not every person is equally suggestible and open to change.” Nevertheless, to say goodbye to cigarettes once and for all, hypnosis is the proven most effective method.
“In medical applications, hypnotizing is much easier because the need and necessity to follow clear instructions is much greater,” explains Loth. The suggestibility is increased even if hypnosis has not yet been applied. A good example is a new approach to emergency medicine that significantly increases survival chances, for example in heart attacks, through calming hypnotherapeutic communication.
Medical hypnosis is used today in many areas of psychotherapy and medicine. It is particularly effective in psychological stress, stress-related complaints, and pain treatment.
The most important areas of application include:
Anxiety disorders
Hypnosis can help regulate anxiety responses and build inner security. It is used for exam anxiety, phobias, or social anxieties, among others.
Depressions
In hypnotherapy, positive inner images and personal resources are activated to break rigid thought patterns and develop new perspectives.
Addiction (e.g., smoking)
Especially in smoking cessation, hypnosis is considered one of the most effective methods. It helps to sustainably change unconscious habits.
Sleep disorders
Hypnosis can help reduce inner restlessness and stabilize the natural sleep-wake rhythm.
Burnout und Stress
Durch den Zugang zum Unterbewusstsein lassen sich Stressmuster erkennen und verändern. Hypnose fördert Entspannung und unterstützt dabei, neue Strategien im Umgang mit Belastung zu entwickeln.
Weitere Einsatzgebiete sind psychosomatische Beschwerden sowie die begleitende Behandlung chronischer Schmerzen und medizinischer Eingriffe.
Auch im Operationsaal werden hypnotische Verfahren mehr und mehr eingesetzt. Eine der Pionierinnen, die belgische Ärztin Dr. Marie Faymonville, nutzt sie schon seit Anfang der 1990er-Jahre. Vorteile sind, neben der beruhigenden Wirkung, dass das Gehirn mithilfe von Hypnose dazu gebracht werden kann, den Schmerz nicht mehr wahrzunehmen.
Norbert Loth erklärt das so: „Schmerz hat zunächst einmal eine Signalfunktion – sobald das Bewusstsein das weiß, bringt das keine neue Information mehr, und es kann sich wundersamerweise aus der Wahrnehmung des Schmerzes zurückziehen.“
Thanks to this so-called dissociation, one can safely immerse themselves in fantasy worlds. Other proven facts are that anesthetics can at least be reduced, blood loss is lower, and recovery is faster.
Particularly impressive is the use of hypnosis in neurosurgery. Here, so-called awake surgeries are performed, where patients must remain responsive during the procedure to check important brain functions.
One of the specialists in this field in Germany is neurosurgeon Dr. Rupert Reichart, senior physician and head of pain therapy at Rhön Klinikum Campus Bad Neustadt . He is also a trained physician in medical hypnosis. What makes hypnosis so fascinating for him?
"In neurosurgery, sleep-wake procedures are performed to test certain brain functions during surgery," says Reichart. For example, when a brain tumor affects areas of speech, language comprehension, or movement.
Unlike classic light anesthesia, patients under hypnosis are often clearer and more responsive. This allows for more precise testing of functions like speech or movement—a crucial factor, for example, when removing brain tumors.
Even with the so-called deep brain stimulation, which is used in Parkinson's, among other things, hypnosis can offer advantages. Without sedative medications, symptoms such as tremors can be observed unaltered, allowing more precise electrode placement.. "The challenge is to find exactly the point where the stimulation works best and the tremors stop," explains Reichart.
An operation on the brain without anesthesia may sound unimaginable to laypeople. But the brain itself is not sensitive to pain. The painful part is the incision in the scalp, which is done under local anesthesia. The clamp in which the head is clamped is uncomfortable.
Very uncomfortable, but not painful, is the opening of the skull – mainly because of the piercing drill noises. This is where Reichart takes his patients on a journey with a story that can last a few hours.
Also in the Dentistry hypnosis is increasingly used. It not only helps reduce pain but can especially alleviate anxiety – a crucial factor for many patients.
Through targeted suggestions, it is possible to block out disturbing stimuli like drilling noises and promote a relaxed inner perception. In many practices, patients are already prepared with hypnotic techniques before treatment.
Furthermore, hypnosis plays an important role in pain therapy, such as for chronic pain or phantom pain after amputations. It can help change the perception of pain sustainably and improve quality of life.
To better cope with stress, disturbing stimuli, or pain, anyone can also learn the hypnosis technique themselves. The difference to meditation or autogenic training: “Imaging techniques show that in meditation, the cerebrum is evenly activated and not punctually like in hypnosis. Additionally, the switch between the default mode network and the focused mental process is not as pronounced,” says Norbert Loth.
Autogenic training works similarly to self-hypnosis, but the resources are not activated. For this, a suitable induction technique is initially required. Some imagine a pleasant situation (on the beach, in a deck chair), others count backwards or take an imaginary elevator down.
For beginners, fixation methods have proven successful. "The attention is directed to a point, thus informing the brain that something else is about to begin. Until the brain starts remembering natural trance or hypnosis experiences on its own, such as in the form of daydreaming," says Loth.
Then one tells oneself: I am aware that I am sitting here and would like to go into a trance now - so to speak the order to the unconscious to use everything it knows to enter a hypnotic state.
And further: I am aware that I am sitting here and hear (e.g., a honking car outside, chirping birds... - all sounds are included) and feel (the soft chair cushion, the smooth floor) and think (everything that comes to mind).
Soon the brain will start to get bored - and switch to a hypnotic state. This can last up to two hours without a set time limit. If hypnosis is used as a sleep aid, one briefly wakes up, reorients oneself, and transitions into night sleep.
If the trance state is only supposed to last ten minutes, for example, Loth advises giving oneself - that is, the mind - a time in advance and setting an internal clock precisely.
After practicing a few times, this works quite accurately. "But maybe also an unconscious wake-up stimulus comes because something has become more important than the trance - one is not out of it," says the expert. Or simply set an alarm.
But relaxation and stress reduction are not the only things achieved with self-hypnosis: top athletes use it to play through and internalize ideal movement sequences precisely. Those looking for a solution in work or private life can also take a wish or task with them. "And not infrequently, even better ideas come from the subconscious that would never occur to you through stress," says the psychologist.
A clear exclusion criterion for the use of hypnosis would be a psychosis. At the slightest suspicion, the psychotherapist - if necessary with a psychiatrist - must clarify how treatable the patient is. Because hypnosis could trigger extreme anxiety states and dissociative disorders here or completely decompensate someone.
That is why Norbert Loth also warns against stage hypnosis. Since the stage hypnotist does not know his 'guinea pig' and has no psychotherapeutic experience, even harmless questions or suggestions could lead unstable people back into a traumatic situation, with which they are then usually left alone.
