RU2455930C1 - Method of differential diagnostics of mental disorders of endogenic, exogenic and psychogenic origin based on registration of electrodermal activity - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to field of medicine, namely psychiatry, psychotherapy, neurology, psychosomatic medicine. Electrodermal activity of four electrodermal characteristics in 22 leads is registered by means of diagnostic system "AMSAT", by their extraction by means of software tools and substitution in discriminant functions, calculated for exogenic, endogenic and psychogenic mental disorders, as well as for conventional mental standard. Functions are different for men and women. The highest function value determines genesis of mental disorder or its absence.

EFFECT: method makes it possible to carry out differential diagnostics of mental disorders of endogenic, exogenic and psychogenic origin basing on registration of electrodermal activity.

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Description

The invention relates to medicine, namely, psychiatry, psychotherapy, neurology, psychosomatic medicine.

In modern psychophysiology and psychiatry, electrophysiological objectification of mental disorders uses electrodermal activity analysis systems that record skin electrical conductivity and its dynamic characteristics.

In the old analog registration systems - the so-called psycho-galvanometers - recording was carried out on thermal paper. They stopped using more than 10 years ago. Modern systems use digital signal processing and storage, data analysis software, which undoubtedly expands the capabilities of the researcher [1].

In classical systems, a pair of silver electrodes is used, placing them on the inner surface of the middle or distal phalanges of the index and middle fingers. Both foreign [2] and domestic analogues are known, based on the same electrophysical measurement criteria [3].

Figure 1 shows the methods of applying electrodes in traditional systems for recording electrodermal activity, where # 1 indicates the method of location on the inner surface of the middle phalanges of the index and middle fingers, # 2 - on the inner surface of the distal phalanges of the index and middle fingers, # 3 - on the elevation of the tenar and hypotenar.

The range of practical application of these systems, due to the lack of systematic clinical psychophysiological studies in the field of clinical psychiatry, does not allow us to talk about a real differentiation between different groups of mental disorders. The study of electrodermal activity in patients with mental disorders is at the scientific and experimental stage and is concentrated in the field of endogenous psychoses (schizophrenia, affective disorders), organic, personality and neurotic disorders (post-stress, panic, anxiety, etc.) [4, 5].

Here are some data from world studies of electrodermal characteristics of mental disorders of various origins. The prodromal period of schizophrenic psychosis can be accompanied by a number of psychopathological, phenomenological and behavioral reactions in the form of affective experiences of anxiety, anxiety, depression, somatic complaints, dissomination, fragmentary delusional or hallucinatory experiences. At the psychophysiological level, psychotic exacerbations may be preceded by an increase in skin electrical conductivity, the level of which is restored before the onset of remission [6]. Among patients with schizophrenia, a large percentage of non-responders (individuals in whom an external stimulus does not cause a response increase in electrical conductivity) was revealed — 40–50% against, 10–25% normal [7]. Expanded positive symptoms are accompanied by higher levels of electrical conductivity [8], which in turn is a predictor of successful therapeutic efficacy [9]. The prevalence of negative psychopathological symptoms, unfavorable in terms of clinical prognosis, on the contrary, is accompanied by low electrodermal activity [10]. Neuroleptic therapy reduces electrical conductivity, which is most likely due to their anticholinergic action [11, 12]. The study of electrodermal activity in patients with major depressive disorder made it possible to differentiate groups of patients with medium and high suicidal risk [13, 14].

In the case of personality disorders, a characteristic phenomenon is electrodermal hyporeactivity, at the psychophysiological level, indicating emotional smoothness, callousness and a high threshold for the occurrence of anxiety and fear in psychopathic subjects [15]. Similar data were obtained in adolescent studies - individuals prone to psychopathization exhibit electrodermal hyporeactivity and are often nonresponders [16].

Clinical manifestations of psychophysiological variability in neurotic, psychosomatic and psychogenic disorders are associated with sympathetic dysregulation and are accompanied by changes in heart rate, respiratory rate, gastrointestinal function, sweating, salivation, urination, etc. Characteristic features of electrodermal activity in post-traumatic stressful and increased level of skin electrical conductivity and electrodermal hyperreactivity [17].

Thus, the electrodermal activity, along with the existing biomarkers of neuropsychiatric diseases, which include abnormal neuroanatomical, neurophysiological, neurocognitive and genetic characteristics [18], is a dynamic indicator of the functional state of the nervous system and is subject not only to emotional influences, but also to stress and nosogenic damaging factors.

The above studies are valuable in understanding the pathogenetic links of mental disorders, but are almost completely divorced from real clinical practice. In psychiatry and neurology, an auxiliary tool is needed for differential diagnosis in cases of complex, erased, mixed, masked forms of neuropsychiatric pathology, which are currently found everywhere.

The closest in technical essence is the recording of electrodermal activity using the hardware-software complex of topical prenosological assessment for biologically active areas of the skin "AMSAT" [19], based on the use of an alternative electrode application scheme that allows you to cover different areas of the skin, also called biologically active zones (BAS). The appearance of the device is shown in Fig. 2, the circuit of the electrodes and the lead system - in Fig. 3. The feasibility of using this system is supported by the presence of functional interhemispheric and structural asymmetries of the brain [20, 21] and reports of abnormal psychophysiological and structurally functional lateralization of the brain in psychiatric disorders of exogenous, endogenous and psychogenic genesis [22, 23].

The working set of the AMSAT system includes a measuring unit with an autonomous power supply, a set of 6 electrodes, a cable with connectors for connecting the measuring unit to a computer, a working computer program that controls the measurement process and the psychophysiological and mathematical processing of the data obtained (requires IBM-compatible Personal Computer). On the front panel of the measuring unit are indicators for turning on the device and battery charge, on the rear panel are connectors for connecting electrodes, a cable for connecting to a computer and a battery charge switch.

The kit allows you to register skin conductivity between three pairs of electrodes (forehead, arms, legs) in 22 leads. The system uses a diagnostic test signal with a voltage of up to 5 volts, the current strength does not exceed 50 μA, the pulse repetition rate is 10 Hz, which meets the safety requirements [24].

It should be noted that this system is designed to "assess the functional state of the body, the spinal column and the associated segmental-neurological apparatus and visceral organs of a person" [24], it is aimed at the use in somatic inpatient and outpatient medical institutions, but the functional allows you to directly differentiate mental disorders, with the aim of which a series of clinical and psychophysiological studies were conducted in patients with different genesis of ps hicheskih disorders.

The task is to conduct a differential diagnosis of mental disorders of endogenous, exogenous and psychogenic origin based on registration of electrodermal activity.

The task is achieved by recording and evaluating the results of studies of electrodermal activity with an analysis of four electrophysiological characteristics in each of 22 leads with a further determination of the genesis of mental disorders.

The method of differential diagnosis of mental disorders of endogenous, exogenous and psychogenic origin based on the registration of electrodermal activity is as follows.

1. Preparation for the examination. Before the study, the patient removes metal objects and synthetic things, exposes the soles of the feet. The disinfectant wipe wipes the skin of the forehead, hands and feet (the places to which the system electrodes are connected). Immediately before the measurement, the patient rests lying on the couch or reclining in the chair for at least 5 minutes. The surface of all electrodes before examination is treated with 70 ° ethanol.

2. The technique of the survey. According to the marking of the electrodes (left - right), the cuff with the frontal electrodes is fastened on the patient's head (the distance between the electrodes and their height are selected so that the electrodes are located on the frontal tubercles); the patient picks up the hand electrodes and puts his bare feet on the foot electrodes, after which they launch a computer program that controls the measurement and recording of the data. During the measurement, the patient should stand still, not moving, keep the electrodes evenly. The examination process takes no more than 2 minutes.

3. Estimated characteristics. Next, the obtained results of electrodermal activity are analyzed. The system allows you to evaluate four psychophysiological characteristics in each of 22 leads:

1. int is the initial level of electrical conductivity;

2. pik - reactive component of conductivity, reflecting the capacitive characteristics of representative BASs;

3. BFO - the basic factor of deviation - an integrative quantitative indicator that interprets the primary data as a percentage of deviation from the conventional norm - from -100 to +100;

4. BCS - basic colloidal shift - an indicator calculated according to the mathematical algorithm embedded in the diagnostic system and characterizing the colloidal state of aggregation in the body under the influence of dynamic factors of electrical processes in arbitrary units.

4. Extraction of psychophysiological characteristics by program methods. In the software shell of the "AMSAT" diagnostic system, the "Group Analysis" command is selected. In the dialog box that appears, the "Protocol" button is activated and in the dialog box that appears, mark the parameters for output to the text file (name, age, date of examination, data array (horizontal), base deviation factor, base colloid shift), indicate the preferred name of the text file and confirm your choice with the OK button. The created text file is placed in the / Tools directory of the AMSAT shell, from where it is opened by an external text editor and the mathematical values of the electrodermal characteristics are extracted.

5. Substitution of examination results into discriminant functions. The extracted characteristics are substituted into the discriminant formulas calculated for the exogenous (y1), endogenous (y2), exogenous (y3) genesis of mental disorders and for the conditional mental norm (y4). The letters indicate the psychophysiological characteristics, the number after them is the number of the lead.

The discriminant functions were obtained as a result of clinical, psychophysiological, and statistical-mathematical (descriptive, comparative, dispersive, and discriminant analysis [25, 26, 27, 28]) studies of the electrodermal activity of 469 patients of the Border Clinic of the State Medical Academy and the Novocherkassk Branch of the Rostov Regional Psychoneurological Dispensary, and also 132 conditionally healthy volunteers without obvious signs of mental or somatic pathology - students and teachers of the Stavropol State University sity.

6. Interpretation of the results and differential diagnosis. The basis for assigning an object to a specific genesis of mental disorders or to a conditional norm is the maximum value of the corresponding discriminant function. When recognizing the genesis of mental disorders in women using the above discriminant functions, the recognition quality was 63.9%, in men - 63.5%, which makes it possible to conduct differential diagnosis of mental disorders of endogenous, exogenous and psychogenic origin.

Physiological, neuroanatomical and electrophysical aspects of recording electrodermal activity

The first studies of dermal electrical conductivity in neurophysiology and psychiatry date back to the late 19th century. So Vigouroux (1879, 1888) studied electrodermal resistance in various diseases, and Fere (1888), passing a weak electric current between two cutaneous electrodes, recorded an increase in electrical conductivity when exposed to external stimuli (visual, acoustic, gustatory, olfactory) [1]. Tarhanov (1890) discovered fluctuations in the biopotentials of the skin under the influence of exogenous and emotional factors. This phenomenon was named after the author [29]. Jung applied the obtained data in an attempt to objectify mental processes [30]. The interest in studying the electrical capacitive and electroconductive properties of the skin and biological environments of the body in relation to various physiological processes - growth, development, damage, regeneration, death, emotions and cognitive functions, initiated a number of experimental and theoretical works of the twentieth century.

The physical aspects of recording electrodermal activity are based on Ohm's law, according to which skin resistance is directly proportional to voltage and inversely proportional to current

R = U / I,

where R is the resistance (Ohm), U is the voltage (V), I is the current strength (A).

Considering the fact that in biological systems an electric current conductor is a medium with variable electrochemical properties, experimental psychophysiology uses a skin conductivity index calculated on the basis of a constant voltage value and the resulting current strength on a passive electrode. The unit of conductivity in biological systems is microsiemens (µS).

The contribution to the total indices of skin electrical conductivity is made by: the electrolyte composition of sweat, blood, lymph and intercellular fluid, but to the greatest extent - the activity of eccrine sweat glands, which are regulated by cholinergic sympathetic innervation [31].

The emotional, stress, and nosogenic variability of the electrical conductivity indices depends on the activity of the sympathetic nervous system, the neurons of which trigger the process of perspiration. Higher control over electrodermal activity is exercised by the prefrontal cortex, basal ganglia, hypothalamus, limbic system, and reticular formation of the brain stem [1]. Neuroanatomical aspects of the regulation of electrodermal activity are presented in Fig. 4.

In the human body, two types of sweat glands are known - apocrine and eccrine. The evolutionary meaning of the former lies in the production of signaling fluids that serve as regulators of sexual, gender, social, behavioral and other relationships in the animal world. The eccrine glands, originally located on the palms and feet of primates, served to increase the tenacity of grasping movements during their movements in nature. The regulation of sweating is thus an adaptive response that ensures the survival of the subject in situations of vital threat and carries signs of cognitive processing of sensory stimuli. The thermoregulatory properties of eccrine glands are a later and less “behavioral” evolutionary step.

Differential Diagnostic Examples

Example 1

Woman with Organic Psychotic Disorder, 43 years old. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 7 Int 8 Int 12 Int 20 pik 7 pik 12 pik 21 pik 22 BFO 3 BFO 4 BFO 18 BCS 1 BCS 3 BCS 9 85.3 87.4 87.2 89.9 28.7 29.6 29.5 29.1 9.9 -46.2 12,2 30.3 30,0 32.8

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y1 is of greatest importance, which corresponds to exogenesis, therefore, the disease of this patient with a certain degree of probability belongs to the group of exogenous mental disorders.

Example 2

Woman, 30 years old, diagnosed with schizophrenia with a predominance of negative psychopathological symptoms. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 7 Int 8 Int 12 Int 20 pik 7 pik 12 pik 21 pik 22 BFO 3 BFO 4 BFO 18 BCS 1 BCS 3 BCS 9 98.1 97.6 96 97.7 28.1 28.6 29.2 29.3 -52.3 -77.7 -55.3 51.1 45,2 46.3

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y2 is of greatest importance, which corresponds to endogenesis, therefore, the disease of this patient with a certain degree of probability belongs to the group of endogenous mental disorders.

Example 3

Woman, 69 years old, with panic disorder. The following are the AMSAT indicators of the subject included in simple classification functions.

Int 7 Int 8 Int 12 Int 20 pik 7 pik 12 pik 21 pik 22 BFO 3 BFO 4 BFO 18 BCS 1 BCS 3 BCS 9 94.3 89.1 84.5 89.7 29.0 28.5 28.8 29.0 -90.2 -91.4 -90.2 36.1 29.9 36.3

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y3 is of greatest importance, which corresponds to psychogenesis, therefore, the disease of this patient with a certain degree of probability belongs to the group of psychogenic disorders.

Example 4

Woman, 18 years old, without obvious signs of mental or somatic pathology. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 7 Int 8 Int 12 Int 20 pik 7 pik 12 pik 21 pik 22 BFO 3 BFO 4 BFO 18 BCS 1 BCS 3 BCS 9 89.3 89.2 85.7 87.5 28.5 27.0 29.0 29.6 21.8 20.3 20.6 10,4 4.2 -7.0

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y4 is of greatest importance, which corresponds to the norm, therefore, in this patient with a certain degree of probability there is no mental pathology.

Example 5

Male, 20 years old, with organic nonpsychotic depressive disorder. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 2 Int 3 Int 12 Int 20 pik 7 pik 8 BFO 2 BFO 15 BFO 17 BFO 18 BCS 1 BCS 7 BCS 9 BCS 17 BCS 19 85.7 86.6 83,2 83.1 24.7 27.5 28,2 35.7 34.2 23.5 25 -1.9 -1.3 0.3 4.9

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y1 is of greatest importance, which corresponds to exogenesis, therefore, the disease of this patient with a certain degree of probability belongs to the group of exogenous mental disorders.

Example 6

A man, 27 years old, with acute schizophrenia. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 2 Int 3 Int 12 Int 20 pik 7 pik 8 BFO 2 BFO 15 BFO 17 BFO 18 BCS 1 BCS 7 BCS 9 BCS 17 BCS 19 53,4 55.9 92.1 92.5 29.1 29.1 -86.9 -82.5 -90.0 -84.8 24.3 30,4 29.3 -11.9 -0.5

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y2 is of greatest importance, which corresponds to endogenesis, therefore, the disease of this patient with a certain degree of probability belongs to the group of endogenous mental disorders.

Example 7

Male, 48 years old. The diagnosis is a mixed anxiety and depressive disorder. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 2 Int 3 Int 12 Int 20 pik 7 pik 8 BFO 2 BFO 15 BFO 17 BFO 18 BCS 1 BCS 7 BCS 9 BCS 17 BCS 19 85.9 63.3 83.6 84.7 29.7 29.8 19.1 15.3 -61.5 -34.9 21,4 27.9 30,4 -20.4 -19.8

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y3 is of greatest importance, which corresponds to psychogenesis, therefore, the disease of this patient with a certain degree of probability belongs to the group of psychogenic disorders.

Example 8

A man, 17 years old, without obvious signs of mental or somatic pathology. Below are the AMSAT indicators of the subject, included in simple classification functions.

Int 2 Int 3 Int 12 Int 20 pik 7 pik 8 BFO 2 BFO 15 BFO 17 BFO 18 BCS 1 BCS 7 BCS 9 BCS 17 BCS 19 95.9 95.3 97.5 96.9 29.8 29.4 76.5 79.8 81.3 71.5 -19.5 -22.5 -23.9 -17.6 -27.1

Substituting AMSAT indicators into simple classification functions, we obtain:

The function y4 is of greatest importance, which corresponds to the norm, therefore, in this patient with a certain degree of probability there is no mental pathology.

Medical, social and economic importance

This method can find its application both in specialized psychiatric hospitals and neuropsychiatric dispensaries as an auxiliary tool for the differential diagnosis of various genesis of mental pathology, as well as in general somatic departments and outpatient clinics, as a tool for screening and express diagnostics. It should be noted that it is in somatic hospitals and polyclinics that the number of erroneous diagnoses is high against the background of a significant proportion of psychosomatic pathology, masking the hidden course of depression, schizophrenia and other mental disorders as cardiological, gastroenterological and neurological complaints. Often such subjects for years unsuccessfully seek the help of a therapist or neurologist, getting into the field of view of a psychiatrist already at the stage of chronicity of the process, complicated by emotional-volitional deficiency, the presence of suicidal thoughts or actions. This sometimes leads to dramatic consequences - where they could have been avoided.

INFORMATION SOURCES

25. Utkin V.A. Statistical Technologies in Medical Research: Monograph. - Pyatigorsk: GNIIK, 2002 .-- 214 p.

26. Utkin V.A. Diagnosis, classification and prediction in clinical, experimental and reconstructive medicine. Diss ... Dr. med. sciences. - Pyatigorsk, 2003 .-- 256 p.

27. Utkin V.A. Methodological aspects of mathematical-statistical analysis of medical data. Part 1. Analytical constructs of medical and statistical surveys // Medical Bulletin of the North Caucasus, 2008; No. 4 (12): S.67-73.

28. Utkin V.A. Methodological aspects of mathematical-statistical analysis of medical data. Part 3. Classification and diagnosis in modern medicine using discriminant and cluster analysis // Medical Bulletin of the North Caucasus, 2009; No. 4 (16): S.62-65.

29. Bleicher V.M., Kruk I.V. Explanatory Dictionary of Psychiatric Terms. - Voronezh: NPO MODEK, 1995.

30. Neumann, E., Blanton, R. The early history of electrodermal research / E. Neumann, R. Blanton // Psychophysiology. - 1970. - T.6. - No. 4. - S. 453-475.

31. Human physiology: Textbook. for students honey. Universities / Ed. V.M.Smirnova. - M.: Medicine, 2002 - S.608.

Claims (2)

1. A method for differential diagnosis of mental disorders of endogenous, exogenous and psychogenic origin based on registration of electrodermal activity, including recording four psychophysiological characteristics of electrodermal activity in 22 leads by the AMSAT diagnostic system: int - initial level of electrical conductivity, pik - reactive component of conductivity, reflecting capacitive characteristics representative BAS-biologically active zones, BFO - the base deviation factor and BCS - the base collo an ideological shift, characterized in that the obtained values of psychophysiological characteristics are substituted into the discriminant functions of exogenous (s1), endogenous (s2), psychogenic (s3) genesis of mental disorders and conditional norm (s4), for women, having the form:
y1 = 0.7012 × age-0.0686 × int7-0.2985 × int8 + 1.6939 × int12-0.8983 × int20 + 7.7930 × pik7 + 1.5798 × pik12 + 3.0067 × pik21-1.1813 × pik22 + 0.0518 × BFO3 + 0.0921 × BFO4-0.0362 × BFO18 + 0.7662 × BKS1 + 0.4433 × BKS3-0.4815 × BKS9-198.3890;
y2 = 0.6746 × age-0.0289 × int7-0.3487 × int8 + 1.5911 × int12-0.8170 × int20 + 7.6913 × pik7 + 1.6911 × pik12 + 3.0561 × pik21-1.2057 × pik22 + 0.1371 × BFO3 + 0.0978 × BFO4-0.1478 × BFO18 + 0.7374 × BKS1 + 0.5062 × BKS3-0.5325 × BKS9-195.3523;
y3 = 0.6949 × age-0.1946 × int7-0.4236 × int8 + 1.5905 × int12-0.9241 × int20 + 7.5991 × pik7 + 1.8084 × pik12 + 3.1711 × pik21-1.2323 × pik22 + 0.0082 × BFO3 + 0.0838 × BFO4-0.0000 × BFO18 + 0.7357 × BKS1 + 0.4428 × BKS3-0.4832 × BKS9-202.6567;
y4 = 0.5719 × age-0.2303 × int7-0.8123 × int8 + 1.7729 × int12-0.7649 × int20 + 8.2696 × pik7 + 1.2958 × pik12 + 3.0150 × pik21-1.1349 × pik22 + 0.1494 × BFO3 + 0.0922 × BFO4-0.1412 × BFO18 + 0.7461 × BKS1 + 0.4299 × BKS3-0.4593 × BKS9-201.6183,
and for men:
y1 = 0.5949 × age + 0.7059 × int2 + 0.2687 × int3 + 6.8950 × int12-5.8887 × int20 + 17.1262 × pik7 + 9.2494 × pik8 + 0.5609 × BFO2-0.9032 × BFO15 + 0.0346 × BF017-0.1591 × BFO18 + 0.4217 × BKS1- 0.0906 × BKS7-0.1012 × BKS9 + 0.9409 × BKS17 + 1.5474 × BKS19-457.1445;
y2 = 0.5588 × age + 0.7399 × int2 + 0.2242 × int3 + 6.8592 × int12-5.8983 × int20 + 18.0449 × pik7 + 8.5005 × pik8 + 0.5561 × BFO2-0.9215 × BFO15 + 0.0086 × BFO17-0.1184 × BFO18 + 0.3976 × BKC1- 0.0984 × BKS7-0.1281 × BKS9 + 0.9314 HBKS17 + 1.6297 × BKS19-454.3653;
y3 = 0.7138 × age + 0.7864 × int2 + 0.2363 × int3 + 7.0484 × int12-6.0469 × int20 + 18.1977 × pik7 + 8.4053 × pik8 + 0.5391 × BFO2-0.9205 × BFO15 + 0.0184 × BFO17-0.1340 × BF018 + 0.4102 × BKS1- 0.1125 × BKS7-0.1127 × BKS9 + 0.9172 × BKS17 + 1.6296 × BKS19-469.7084;
y4 = 0.4715 × age + 0.6815 × int2 + 0.2654 × int3 + 6.9078 × int12-5.9003 × int20 + 17.7090 × pik7 + 8.6792 × pik8 + 0.5088 × BFO2-0.8654 × BFO15 + 0.0342 × BF017-0.1324 × BFO18 + 0.4148 × BKS1- 0.1297 × BKS7-0.0800 × BKS9 + 0.9480 × BKS17 + 1.5037 × BKS19-453.0513,
and the highest value of the function determines the genesis of a mental disorder or its absence. 2. The method of differential diagnosis of mental disorders of endogenous, exogenous and psychogenic origin based on the registration of electrodermal activity according to claim 1, characterized in the extraction of psychophysiological characteristics by program methods.

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