What is Hypnosis?

Hypnotic State is Different from Night Sleep

Alexander N. Shepovalnikov, M.D., D.Sc.

Hypnosis was named after Greek God of Sleep – Hypnos, and for a long time it was believed that the hypnotic state is just an artificially induced sleep identical to the night sleep. With the development of sleep science and a new methodology considerable progress was made about neuro-physiological mechanisms of natural sleep, while in- depth studies of the nature of hypnotic state are still in its infancy.

It remains unknown why natural sleep and the hypnotic state are similar in some characteristic (e.g. behavior patterns, the possibility of hypnotic state to transform into sleep and sleep into hypnosis) and very different in all other ways, especially in EEG patterns. The recent studies using positron emission tomography demonstrated selective activation of some and inactivation of other brain structures but it was not enough to come up with general understanding what hypnosis is.

To understand hypnosis as a new methodology that shows integrative interbrain relationships was developed. This methodology has been called Interregional Cortical Interaction (ICI). It was developed by scientists at the Sechenov’s Institute of Evolutionary Physiology, Russian Academy of Science, St. Petersburg.

Using this unique technique Russian scientists studied 26 healthy subjects during the night sleep and in deep hypnotic states. Multi-channel analysis of EEG represented in three-dimensional space of vectors (factors) showed that the internal connections between cortical centers in each hemisphere were stable at restful awake of healthy subjects reflecting the regular and stable patterns of synchronization between cortical fields. These inter-spatial organizations vary somewhat in the different stages of sleep but stay similar in its major points. During the hypnotic state, however, interrelationships between cortical fields change considerably. High orderliness between cortical centers in wake and sleep is significantly reorganized in hypnosis. Frontal lobes especially in the right hemisphere, responsible for judgment and contact with the environment lost their connections with posterior temporal and occipital zones, thus, lost their “hierarchy” and orderliness.

This temporal autonomy of different regions of the brain allows such magical phenomena that is possible to see only in hypnosis, but impossible to see under regular conditions in sleep or awake. To say it simply, the nature of hypnosis is “reprogramming” for temporal “independency” of some body systems from each other and “over-dependency” of other systems from other parts of the brain. This opens the unique opportunity to influence the deep body functions without medications, but using hypnotic states.


Alexander .N. Shepovalnikov, M.D., D. Sc., is Honorary Scientist of the Russian Federation. Full Professor and Director of the Neurophysiology Section of the Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Science, St Petersburg, Russia.