How and why does hypnosis work in the brain?

Scientists study the processes in the brain in hypnosis
Hypnosis is used successfully for various therapeutic purposes. However, what processes take place during hypnosis in the brain remains largely unclear. Psychologists at the University of Jena have set themselves the goal of developing a "Brain Theory of Hypnosis". First results are now available.

"With the help of hypnosis people get used to smoking, find better sleep and even withstand dental visits without pain," reports the University of Jena. However, what processes are taking place in the brain of a hypnotized person and how exactly hypnosis works remains open to now. Scientific answers to the questions should be provided by a research project at the Friedrich-Schiller-University Jena. First results of the project have now been published in the scientific journal "Scientific Reports".

Hypnosis has been shown to have an effect, yet it remains unclear which processes are occurring in the brain. Psychologists from the University of Jena were now able to detect altered patterns of activity in hypnotized subjects' brains. (Image: Hetizia / fotolia.com)

As part of their project, the scientists examined, according to the study leader Prof. Dr. med. Wolfgang Miltner from the Institute of Psychology of the University of Jena, how the brain allows hypnotic states. "Currently, we have taken a closer look at the processing of visual stimuli," says Miltner. For this purpose, three groups of probands have been investigated: persons who are very suggestible for hypnosis; Individuals who tend to be mediocre and those with little hypnotic susceptibility.

Suggested board in front of the eyes
"We had her hypnotized looking at a screen where we showed various symbols, such as a circle or a triangle," explains Dr. Barbara Schmidt from the University of Jena, the structure of the experiment. The task of the test subjects was to count a certain symbol, so to concentrate on it. According to Dr. But at the same time, they should imagine a board in front of their eyes. "Due to the suggested obstruction, the number of counting errors increased significantly," says the psychologist. The effect had occurred in all three test groups, most pronounced, however, in the most hypnotizable subjects.

Altered brain activity under hypnosis
During the experiments, the subjects' brain activity was measured by means of an electroencephalograph (EEG). Here, it has been shown that the resulting neuronal processes of the brain were extremely reduced in the processing of the symbols, about 400 milliseconds, after the subjects have seen the icon to pay special attention to. The brain activity has decreased significantly, although it would normally have to be very high at this time, explains Schmidt. A short time before - up to 200 milliseconds after the presentation of the stimulus - no abnormalities had been noted.

Processing of the stimuli influenced
The measurement of brain activity showed that the simple perception still takes place, deeper processing, such as counting, but greatly impaired, the scientists report. The activity patterns show how hypnosis influences individual regions of the brain in visual stimulus recording. Further experiments will investigate the processing of acoustic stimuli under hypnosis and the effects of hypnosis in pain relief.

Establish serious hypnosis research
"Until the 1920s hypnosis was part of medical education and today it is used again in anesthetics," explains Prof. Miltner. However, there is little scientific research into why hypnosis works like an anesthetic. There are also too many esoteric speculations on this topic, so that scientists are often confronted with skepticism in this area, complains the psychologist. "We no longer have to show that hypnosis is effective because that's proven. Above all, it is important to find out why and how such strange perceptual changes are possible in hypnotized people, "the expert concluded. It is important to establish a serious hypnosis research. (Fp)