Hypnotism and Obstructing the 'Inner Eye'

“While they were under hypnosis, we had them look at a screen on which we showed them various symbols, such as a circle or a triangle,” explains Dr Barbara Schmidt, who conducted the experiment. “The test participants were given the task of counting a particular symbol. 

 

At the same time, they were told to imagine that there was a wooden board in front of their eyes. As a result of the suggested obstruction, the number of counting errors rose significantly.” The effects were observed in all three test groups, but were strongest in those participants who were easiest to hypnotise.

 

While under hypnosis, the test participants had to react on various symbols. In order to observe brain activity, the participants were linked up to an EEG. In this way, the psychologists were able to find out how hypnosis influences specific regions of the brain while it receives a visual stimulus.

Credit: Jan-Peter Kasper/FS

In order for the researcher to observe brain activity as well, the test participants were linked up to an electroencephalograph (EEG). “When we look at the neural processes that take place in the brain while processing the symbols, we see that around 400 milliseconds after the presentation of the to-be-counted symbol, there is an extreme reduction in brain activity, although it should normally be very high,” explains Schmidt. “

However, a short time before this – up to 200 milliseconds after presentation of the stimulus – there are no differences to be seen.” This means, therefore, that simple perception still takes place, but that deeper processing operations, such as counting, are greatly impaired. In this way, the University of Jena psychologists were able to find out how hypnosis influences specific regions of the brain while it receives a visual stimulus.

Establishing serious hypnosis Research

Further experiments are planned over the years to come. The researchers will be investigating alterations in the processing of acoustic stimuli as well as pain relief during hypnosis. “Until the 1920s, hypnosis was a standard part of medical training and it is being used again today in anaesthesia,” reports Miltner. “However, there is hardly any scientific research examining the reasons why hypnosis works as an anaesthetic.” 

Hypnotist directing people to do unusual activities

Contacts and sources:

Institute of Psychology of the Friedrich Schiller University Jena