Time and again, we hear the question, what is hypnosis really and is it even real? A brain signature of being hypnotized was first recognized in 2012 with functional MRI (fMRI), a type of MRI that showed brain . Sections of the brain related with executive control and attention were evidenced to be involved.
More particularly, hypnotized subjects displayed greater co-activation between parts of the brain’s executive-control network (in-charge of basic cognitive functions) and the salience network (dictates which stimuli must be given attention). Both networks in the brain are activated in unison. In those who were not hypnotized, no such connectivity was seen.
What elevated these experiments to a higher league is the fact that researchers used fMRI to detect the parts of brain that responded when subjects analyzed colors. The color sections in both left and right hemispheres were stimulated when the subjects were made to perceive colors. The scientists concluded that hypnosis is indeed an independent psychological state and surely not the outcome of adopting a role.
Another fascinating observation from these studies were the hemispheric changes between non-hypnotized and hypnotized brain. When non-hypnotized subjects were requested to point out colors from a black-and-white picture, only the right hemisphere was activated. The left hemisphere, which deals with reason and logic, only responded under hypnosis.
Another research used positron-emission tomography (PET) to look into cerebral blood flow in hypnotized subjects. The hypnotic state was in relation to activation of many mostly left-sided cortical regions, plus a few right-sided areas. To understand more about hypnosis, visit https://en.wikipedia.org/wiki/Hypnosis#History.
The trend of activation shared a lot of similarities with mental imagery, from which it showed differences by the relative deactivation of the precuneus (handles visuo-spatial imagery, episodic memory retrieval and self-processing operations of the brain). This activation trend proved to be similar with mental imagery, from which it differed with the relative deactivation of the precuneus, the area of the brain in charge of episodic memory retrieval, visuo-spatial imagery and self-processing operations. Some scientists believe that under hypnosis, the subjects simply activate, to a significant extent, the brain sections used in imagination, but without actual perceptual changes.
Another functional MRI experiment shows that during hypnosis, there is controlled activity in the anterior cingulate cortex (affects learning, memory and emotions) and the visual areas of the brain. The findings hints that hypnosis impacts cognitive control by regulating activity in particular brain areas, including early visual modules.
In multiple studies, hypnotizable subjects exhibited substantially more brain activity in the emotion and behavior-affecting anterior cingulate gyrus, as compared to participants who are non-hypnotized. The anterior cingulate gyrus acts on errors as well as evaluates emotional chagnes. Prefrontal cortex is related to with higher level cognitive processing and behavior. Know about hypnosis license here!
Comparison of findings from several studies also puts contradictory results to fore. Many regions of the brain seem to respond in different experiments. This can be related to various experimental techniques, both in terms of hypnotic approach and equipment used for the studies, click for more!