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Click here to see actual brainwaves of a client under hypnosis using a stereo IBVA recorded with top Hypnotherapist Ursula James, London

IBVA as a measuring device can show a professional when their client is in a light trance state, for effectively receiving hypnotherapy. IBVA brainwave data really is the 'convincer', and the sensor band can be worn during a session by the client. Hypnotherapists induce slow brain wave states, Alpha waves are present during the 'light hypnotic' state used by hypnotherapists for suggestion therapy. Hypersuggestibility is characterized by a narrow focus of attention and increased likelihood to act upon suggestions given by an operator.

Click here to download a PDF from the NeuroNetwork detailing Frontal Lobe changes in EEG during Hypnosis as measurable with an IBVA

'Hypnosis really changes your mind'
NewScientist.com, 13:28 10 September 2004 by Anna Gosline

Hypnosis is more than just a party trick, it measurably changes how the brain works, says a UK researcher. Hypnosis significantly affects the activity in a part of the brain responsible for detecting and responding to errors, says John Gruzelier, a psychologist at Imperial College in London. Using functional brain imaging, he also found that hypnosis affects an area that controls higher level executive functions.
“This explains why, under hypnosis, people can do outrageous things that ordinarily they wouldn’t dream of doing,” says Gruzelier, who presented his study at the British Association for the Advancement of Science Festival in Exeter, UK.
The finding is one of the first to indicate a biological mechanism underpinning the experience of hypnosis. Gruzelier hopes it will also benefit emerging research showing, for example, that hypnosis can help cancer patients deal with painful treatments.
Highly susceptible
Gruzelier and his colleagues studied brain activity using an fMRI while subjects completed a standard cognitive exercise, called the Stroop task.
The team screened subjects before the study and chose 12 that were highly susceptible to hypnosis and 12 with low susceptibility. They all completed the task in the fMRI under normal conditions and then again under hypnosis.
Throughout the study, both groups were consistent in their task results, achieving similar scores regardless of their mental state. During their first task session, before hypnosis, there were no significant differences in brain activity between the groups.

But under hypnosis, Gruzelier found that the highly susceptible subjects showed significantly more brain activity in the anterior cingulate gyrus than the weakly susceptible subjects. This area of the brain has been shown to respond to errors and evaluate emotional outcomes.
The highly susceptible group also showed much greater brain activity on the left side of the prefrontal cortex than the weakly susceptible group. This is an area involved with higher level cognitive processing and behaviour.

Stage hypnotists
Gruzelier concludes that, under hypnosis, these brain areas are having to work much harder to achieve the same cognitive task results. “This is confirming our model of hypnosis with very direct evidence of brain function,” he says.
Peter Naish, at the UK's Open University, says this moves the understanding of hypnosis away from the popular misconceptions created by showy stage hypnotists.
“We have a technique that has now moved towards evidence-based treatments,” he says. “Gruzelier’s work is showing for sure that the brain is doing quite different things under hypnosis than in normal everyday existence.”
Clinical trials of therapeutic hypnosis are starting to confirm its potential benefits. Christina Liossi, a psychologist at the University of Wales in Swansea, recently conducted a study of 80 cancer patients aged 6 to 16.
She found that those under hypnosis experienced far less pain during treatments than control children, who simply talked to the researchers normally.

IBVA and more about how to 'Think Theta'
The EEG display of persons under hypnosis reveal brain activity resembling an altered state of consciousness. In both people highly susceptible to hypnosis and people with low hypnotic susceptibility. Interestingly, the two categories of people displayed different patterns of EEG activity. During a baseline, or rest period, before undergoing hypnosis, higher Theta brain wave power was recorded in the frontal brain areas in those more susceptible to hypnosis. In the period of time before and after the hypnotic induction, those with a low susceptibility to hypnosis displayed an increase in Theta wave activity. Those with high susceptibility had lower Theta waves. All subjects demonstrated an increase in Theta waves during hypnotic induction and alpha wave activity increased as well. Delta waves are more visible when a subject is in a deep trance,

Many scientists have spent a lot of time studying these basic brain waves of the EEG, so there is a lot of basic knowledge about them. Alpha waves are not always present in our brains. For example, in deep sleep there is no Alpha, and if someone is very highly aroused as in fear or anger, again there is virtually no Alpha. Theta waves are seen when there is drowsiness or light sleep. Alpha is seen in wakefulness where there is a relaxed and effortless alertness . So people susceptible to hypnosis may be more relaxed. This may be why so many assert that the mellow, relaxed state of hypnosis awakens the imagination and heightens learning and creativity. A person certainly has more difficultly being imaginative under stress.

The Hypnotic condition put to the test
Scientists Kossylan and Thompson of Harvard University also demonstrated that the brain changes while under hypnosis. They conducted an experiment on only highly hypnotizable people. These people were placed into a positron emission tomography scanner that measures cerebral blood flow in order for "pictures" of their brains to be taken while the experiment was conducted. The subjects were shown a pattern of multi-colored quadrilaterals. They were asked to mentally drain the color from these images. Later, these same people were shown gray rectangles and asked to color them with their minds. When not hypnotized, people who were asked to see color--- whether they did or not showed activity on the right side of the brain. When these people were told to see gray, activity changed on the right side of the brain only also. The experiment was repeated while the subjects were under hypnotism.
Interestingly, both the left and right side of the brains were active in the subject when the experiment was duplicated under the hypnotic condition. The researchers hypothesized that the left side of the brain registered what the subjects were told to see when hypnotized and that the right side registered what people were told to see whether or not they were hypnotized. This is interesting because the left side of the brain is correlated with logic and rational thought. In this experiment, the left side of the brain becomes engaged in what may be considered a creative right-brained activity, but only when it is under hypnosis. Kossylan states that this means that, "hypnosis changes the conscious experience in a way not possible when we are not under hypnosis".

Hypnosis, EEG and Pain
A similar study was conducted in 1999, into the effects of hypnosis on pain perception. A person was asked to place their hand into hot water while in a hypnotic trance and when not in a hypnotic trance. The study measured brain waves in both cases using EEG and positron emission tomography. This study, like the Harvard Study mentioned above, found that there are specific patterns present within the brain, while it is in a hypnotic state. This, however, does not mean that scientist understand hypnosis any more than they did before, but they do know how the brain acts under hypnosis.


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