Results of the research we carried out

The goals of our research were as follows:

1)to differentiate actual state of hypnosis from simulation; in order to so this, we made expert comparison of symptomatology and EEG of actual catalepsy with motor test – arbitrary keeping of extremities that is accomplished by a subject.

2)to describe physiology of hypnosis graphically and accessibly; explain value of EEG-examination of hypnosis in the study of higher nervous activity and brain processes relating to it;

3)to evaluate clinical and psychological features of people regarding their hypnoability;

4)to prove practicality of hypnotic procedures for psychotherapy.

Study of hypnotic state by the means of catalepsy induction unites deprivation, reflex, and ideomotor theoretical approaches. It is assumed that catalepsy is accompanied by complex neurophysiologic shifts in relationship between certain parts of brain which facilitate appearance of changed state in which information processing in brain undergoes transformation. In this state during the condition of inhibition of particular functions of cerebral cortex, stimulation of some subcortex mass that is responsible for the regulations in emotional and motivational functions becomes possible which makes it possible to change components of behavioural process.

It is assumed that catalepsy in its psychophysiological background is a state when it is possible to regenerate some psychic processes.

Our complex approach to the study of this hypnotic phenomenon is based on the induction of akinesia, exclusion of voluntary movements, control over volitional processes, and detection of psychophysiological correlates supplements and extends theoretical and experimental base of hypnotic catalepsy objectification that has been previously studied by Mochutkovskiy O.O. (1888), Krichmer E. (1925), Pavlov I.P. (1951) and Ericson M. (1991).

Personal experience and existing nowadays concepts of suggestibility and hypnoability show that person’s receptiveness of hypnosis depends on individual psychological characteristics, peculiarities of nervous system, method and duration of suggestion, wish, trust and will of a suggested person and competence of hypnologist.

Representatives of our countries’ and foreign schools of hypnology have developed a lot of psychometric scales for the measurement of suggestibility and hypnoability. Almost in all of these scales catalepsy phenomenon is seen as one of the most revealing according to its clinical picture and one of the most important features of hypnosis according to its psychosomatic symptomatology.

During our research we have worked out our own scale for objective evaluation of hypnotic catalepsy depth that registers reliability of clinical and psychological symptomatology appearance with sorting out four types of suggestion-induced catalepsy; cataleptoid state, cataleptiformic state, partial and complete (total) catalepsy that arise depending on personal characteristics of a subject. We have also described ways of subject’s transforming from one phase into another.

Testing revealed increase in hypnoability during stable akinesia which was defined according to symptomatology and detection of true catalepsy by the means of manual examination of muscular tonus, analgesia and other evaluation criteria.

Study of suggestibility and hypnoability we carried out according to different versions offered by Bul P.I. (1975). From foreign scales we used suggestibility scale by Barber and hypnoability scale by Stanford and Harvard schools. We tried to keep on international principles of hypnotherapy scaling.

Barber suggestibility scale (1969) allowed us to form three groups from subjects among which 21% were low-suggestible individuals, 31% were middle-suggestible individuals, and 48% were high-suggestible individuals. Distribution of subjects onto groups in our research is similar to the data form Weitzenhoffer A.M. и Hilgard E.R. (1959) – 24%, 31%, and 42%, respectively – which shows effectiveness of hypnotic methods use and adequate hypnotic scaling.

During the research we have developed our own method for experimental modeling of hypnotic catalepsy which was called “immediate hypnosis”. This particular suggestion technique made it possible to perform hypnotic testing in neurophysiologic laboratories when all subjects were put into deep catalepsy despite the difficult setting for this experiment (a helmet with contact electrodes on head, uncomfortable posture, exposure to light, acoustic, and tactile stimulators). Efficacy of given methodology for catalepsy induction was confirmed: during experiment almost in all subjects complete of partial analgesia and amnesia were observed. Many individuals were in somnambulistic hypnotic condition which later was confirmed by the data from EEG.

In highly-hypnotizable (HH) volunteers stable complete catalepsy was observed. This state appeared on 3rd-4th minute of hypnosis session and lasted maximum to 30-45 minutes. During this state active and passive motional reactions (slow movements in a form of separate pushes, inability to unclench fist, or move hand) was observed. There was no reaction of pain stimulation. The order “Open your eyes!” was accompanied by subject lack of surrounding environment perception, indifferent mimicry and preservation of catalepsy. Accommodation process and oculomotorius reflex were disturbed. There was no response to acoustic and photo stimulation and attempts on behalf of hypnotist to attract subject’s attention by gesticulation. The following features were observed: tetanic catalepsy, complete or partial amnesia, absence of perception of extraneous irritants including purposefully sent signals, complete repeat, and submission to hypnologist’s commands. Sensomotor reactions on suggested hallucinations (both positive and negative) were of olfactory, tactile, visual, acoustic and kinesthetic characters. Posthypnotic suggestions were preformed.

Somnambulistic state, which is the highest stage of hypnosis and during which catalepsy may be spontaneous, was observed. We get a chance to suggest motor reactions. Person being hypnotized can walk, sleep in standing and sitting position with opened eyed. As during it was impossible to move around the room with an EEG-helmet on head, only EEG-parameters of akinesia were registered.

High-stable catalepsy (45 min)

For low-hypnotizable (LH) volunteers low-stable catalepsy was common. It was reached to 5th-7th minute of hypnosis and lasted for 15-20 minutes. Motional reaction on pain stimulation was revealed. Eyes-opening was accompanied by vague perception of surrounding environment with unstable catalepsy.

Unstable catalepsy was manifested in the form of cataleptiod state, rigid catalepsy, and dizzy state.

The following featured were observed: arbitrary blinking and eyes opening and closing; speech inhibition, general passiveness, light muscle weakness and slowing of pulse wave; even and quiet breathing; decrease of skin sensitivity; character face mimicry; dizziness, and motions were inhibited . When within time the given shape of body was gradually lost, the phenomenon of “tooth gear” was observed (extremities go down slowly). Light catalepsy is a common feature, e.g., a lifted hand remains in given position not for a long time. It is impossible to suggest motor reaction.

A hypnotized person can hear, understand, and analyze everything what happens around him or her. Amnesia is absent. General decrease of reflexes is observed. From hypostesia to analgesia. Partial amnesia is common, that is a subject remembers everything happened in hypnosis but reveals any reaction. There some difficulties in post-hypnotic suggestion.

Rigid catalepsy

In middle-hypnotizable (MH) group of volunteers middle-stable catalepsy (cataleptiformic state) was revealed.

Subjective reactions were similar to those in HH but phase duration of drawing into hypnotic catalepsy and being in this state were middle between similar indications in HH and LH groups and made up 5-8 and 30-20 minutes, respectively.

The following features were observed: evident hypodynamia (lifted hand falls down abruptly); eyes catalepsy (it is impossible to open eyes); total absence of muscular resistance; end voluntary movements; loss of coordinated movements; face muscles were relaxed (mimicry of a sleeping person); even, quiet, and deep breathing (number of respiratory movements in a minute was decreased); slow and rhythmic pulse. A subject could not withdraw from hypnosis independently.

A hypnotized person hears dimly and perceives only sharp loud noises. Release is good. Hypnologist’s words are clearly heard and acquired. Amnesia is partial or is absent at all. Hand touch causes normal tension.

Catalepsy in this group was spontaneous (complete) or suggested (partial). Reaction on pain stimulation and command to open eyes was similar to those in HH.

Cataleptiformic state

In general, the data we received during the research were similar to conclusions of hypnologists who carried out researches on other hypnotic phenomena where the catalepsy was involved; besides, they examined individuals but not groups. Consequently, we can consider the chosen hypnotization technique and validity of people differentiation according to hypnoability groups as effective.

Experimental neurophysiologic study was carried our in consideration of the fact that when analyzing EEG parameters of brain activity in catalepsy we examined processes that were responsible for demonstration of will. This is confirmed by the fact that in catalepsy as in on of the types of akinesia models there is voluntary refusal from voluntary movements and thus from demonstration of will. In perspective this permits to increase the level of volitionally processes control.

We examined 14 functional tests among which three major ones that had relation to kinesthetic system were studied carefully. These were background test (BT), motor test (MT) and catalepsy (CT). Comparison of motor and catalepsy functional test made it possible to differentiate visually similar arbitrary and cataleptic retention of body extremities. Other tests were considered auxiliary except for a test on eyes opening during catalepsy which helps to define somnambulists (individuals with maximal hypnoability).

Analysis of EEG parameters shows that total brain electric activity in certain leads is changed in catalepsy or has a tendency to be changed in this state. High-frequency brain rhythms of α- and β-diapasons are suppressed and δ- и θ-rhythms are intensified. In catalepsy low-frequency EEG vibration is transformed and changes in estimated parameters are common for the majority of leads. Domination of left-hemispheric δ-rhythm in catalepsy is manifested more vividly in occipital leads in BT and MT but also is displayed in other leads which may serve as the marker of deep psycho-somatic relaxation. Indexes of right-hemispheric δ-rhythm are displayed weaker than in left hemisphere.

Increase of amplitude and index of θ-rhythm in catalepsy relating BT and MT in left hemisphere may probably be indicators of arising but controlling in this state motor activity. Desynchronization that is observed in catalepsy and displayed by the appearance of θ-rhythm can be considered as the reaction of dominance of biologically negative factors (pain, fear, etc.).

Consequently, we may suppose that catalepsy increases adaptive ability of brain in stress factors’ conditions.

During MT in temporal parts of left and right hemispheric leads absence of θ-activity is observed which confirms absence of catalepsy simulation and may be a marker of this state’s validity.

In catalepsy of frontal leads of right hemisphere amplitude of α-rhythm is significantly increased relative to BT and MT which may indicate brain EA mixing. Insignificant decrease of high-frequency β-rhythms especially in temporal leads may indicate decrease of motor activity, which in general is similar to observations of Nebilitsin V.D. (1974) who had determined the increase of β-2-rhythnic diapason during motion activation.

Comparison of individual average parameters of rhythmic vibration in catalepsy with the corresponding ones in groups revealed that the higher hypnoability level the higher EEG parameters of δ-rhythm in occipital lead of left hemisphere, amplitudes of θ-rhythm in frontal lead of right hemisphere, θ-rhythm index in frontal lead of left hemisphere and lower values of α-rhythm amplitudes in frontal lead of right hemisphere.

Mathematic estimation of IHAC (interhemispheric asymmetry coefficient) parameters especially of spectral capacity helps to demonstrate dominance of δ- and θ-diapason activity in catalepsy in left hemisphere. The evaluation with of IHAC of spectral capacity domination of low-frequency rhythms in one of the hemispheres during catalepsy may be used as important diagnostic criteria of this state.

Hence the characteristic feature of our research are as follows: a considerable accent on psychological characteristics of subjects, qualitative scaled estimation of suggestibility and hypnoability, clinical and psychological evaluation of catalepsy level, chronometry of catalepsy, study of all ranges of brain biorhythms, determination of EEG correlated of cataleptic phenomenon (its differentiation from on the tests), and determination of parameters that confirm validity of catalepsy. We have also sorted out correlations of EEG parameters in groups and high somnambulistic level of hypnosis was revealed in a group with stable catalepsy.

Somnambulistic state

According to Shulgovskiy V.V. (2003), somnambulism appears on the δ-stage of hypnotic activity and in our research particularly this activity dominated in all EEG leads in catalepsy. In our research we have considered not only interhemispheric relations of frequencies of different ranges but also their zonal distribution and possible variants of brain concentration focus changes.

Long-term experience as psychotherapeutist and results of the present research show that hypnotic catalepsy is a model of kinesthetic deprivation with deasfferenting influence on sensory and emotional functions of brain.

Blocade of kinesthetic afferent impulses is revealed in a form of refusal from motor activity. A subject deprivates from a situation real for him or her by switching into the condition of complete immobility. This state, probably, makes it possible to intensify exposure to suggestion and creates precondition for positive controlled change in motivation and as the result in behavior.

Revealing of changes in rate vibration of brain activity during catalepsy especially of its low-frequency range allows not only to judge this state objectively but also to evaluate accurately hypnotic abilities of patients, their deprivation potential and predict results of collaborative work of a psychologist and patient.


  • Physiological testing reveals that the level of suggestibility and hypnoability correlates with stability of hypnosis-modulated catalepsy.
  • Cataleptic phenomenon is most demonstrative in its clinical picture, may be easily checked on falsification and according to its psychosymptomatology is one of the most important indicators of hypnosis.
  • The offered method of “immediate hypnosis” is quite productive for reproduction for hypnotic catalepsy.
  • During hypnosis-modulated catalepsy almost in all leads the left-sided domination of δ-rhythms capacity was registered, especially in frontal and occipital leads in relation to background index and motor test, and also increase of amplitude activity of -range in frontal right lead and -index in left hemisphere.
  • Typical for catalepsy were zero values of -rhythms parameters in temporal leads in motor test that vividly differs from its immobilization phenomenon. During catalepsy a minor activity of interhemispheric asymmetry coefficient of low-range frequency capacity was observed.
  • Chronometrical data of catalepsy reaching and being in it correlated with psychological symptomatology and EEG parameters in relation with groups subdivision of subjects.
  • Symptomatic and EEG criteria for hypnosis-modulated catalepsy which objectify differentiation of this state from its possible simulation and pathological akinesia were defined.


  • Catalepsy may be used as a mean for increasing of patient’s sensitivity to external and internal stimuli and by this exposure to suggestion will be intensified.
  • The symptomatologic, chronometrical and electroencephalographic parameters we have chosen may be used in practical implementation for psychologists and doctors during development of programs for professional selection of individuals, and for deferent psychophysiological researches in psychotherapy.
  • Catalepsy modeling as one of the types of sensory deprivation (low-frequency EEG range) may be used for objectifying of neuro-psychological status of subjects.
  • The frequency diapasons of catalepsy which we distinguished during our research and the device we developed may be used for exposure on sensory systems with psychotherapeutic aim of deprivation state induction and for creation of brain pacemaker for treatment of disease that are connected with its rhythmic activity disorders.
  • Scale for hypnotic catalepsy evaluation, its chronometrical and EEG parameters ma be used in teaching of medical psychology and psychiatry to people working in these spheres; moreover, it can be implemented by psychologists for characteristics of hypnosis levels.



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