A mathematical model for predicting the neuropsychic stability of a cadet

Kobryanova Irina Viktorovna PhD in Psychology Senior researcher, Military Medical Academy 194044, Russia, St. Petersburg, Akademika Lebedeva str., 6 serziulia@gmail.com Nazarov Sergei Sergeevich PhD in Medicine Senior Researcher, Research Institute of Rescue and Underwater Technologies 198411, Russia, St. Petersburg, Lomonosov, Morskaya str., 4 pochta92@mail.ru Serova Yuliya Sergeevna Researcher, Military Medical Academy 194044, Russia, St. Petersburg, Akademika Lebedeva str., 6 serziulia@gmail.com Fettsova Lyutsiya Nail'evna Junior Researcher, Military Medical Academy 194044, Russia, St. Petersburg, Akademika Lebedeva str., 6 serziulia@gmail.com

Yatmanov Aleksei Nikolaevich PhD in Medicine Postgraduate student, Military Medical Academy 194044, Russia, Saint Petersburg, Saint Petersburg, Akademika Lebedeva str., 6 yan20220@mail.ru Other publications by this author

Military service is a special type of activity, in which stress plays a high role on a person ^{[10, 12]}. Overcoming stressful situations is determined by the level of neuropsychiatric stability ^{[1, 13]}.

The issues of neuropsychiatric stability are represented by scientific works, both by foreign psychologists, teachers, and domestic ones. Thus, according to a foreign psychologist, teacher E.V. Melnik, NPU is a set of component individualization of psychological and pedagogical training of a person ^[8]. According to L.I. Spivak– it manifests itself in a tendency to breakdowns in the activity of the nervous system under significant mental and physical stress ^[2]. The author sees the reason in the obvious or hidden violations of the emotional and volitional sphere, as well as in the intellectual self-regulation of a person. Some scientists claim that NPS is frustration tolerance or stress tolerance ^[14].

V.V. Yusupov compares neuropsychiatric stability with a characteristic that determines the state of a stable level of development of cognitive mental processes, emotional-volitional regulation and behavioral reactions in the process of professional activity ^[16]. NPU is defined as a person's ability to regulate their interaction with their environment, as well as act purposefully in this environment ^{[7, 17]}. The main elements of the NPU include: self-esteem, the level of emotional stability, the presence of social approval from the people around him ^[5]. The influence of cognitive abilities on a person's neuropsychiatric stability is of interest ^[11], which was the purpose of the study.

The purpose of the work: to develop a mathematical model for predicting neuropsychiatric stability based on the characteristics of the cadet's cognitive abilities.

Materials and methods. 1822 cadets of the Naval Polytechnic Institute aged from 18 to 26 years were examined. The level of neuropsychiatric stability was determined using the MLO "Adaptivity" technique ^[3]. Military personnel with an NPS level of more than 7 walls (n=565) were assigned to the "High NPS" group, from 4 to 7 walls (n=1186) – to the "Medium NPS" group, 71 surveyed were assigned to the "Low NPS" group with a level of less than 4 walls ^[15]. Cognitive abilities were assessed using the KR – 3 – 85 technique ^[6].

Statistical processing was carried out using the Statistica 10.0 program. The normality of the distribution was checked using the Kolmogorov-Smirnov criterion. Comparative analysis using the parametric t-Student criterion. When conducting multiple comparisons, the Bonferroni correction was applied, that is, in three groups, differences in p were considered statistically significant.<0,017 (0,05/3=0,017) ^[4]. Mathematical modeling was carried out on the basis of discriminant analysis ^[9].

The results and their discussion. When conducting discriminant analysis using the "step-by-step forward" method, a model for predicting the level of neuropsychiatric stability of a cadet was obtained: Wilkes Lambda: 0.95595 approx. F (6.3634)=13.799 p<0.0001 and the discriminant variables are determined (Table 1).

Table 1

Discriminant variables

It was revealed that the combination of cognitive development indicators is a predictor of neuropsychiatric stability of military university cadets.: the ability to establish logical relationships between concepts based on analysis and synthesis operations, the level of development of verbal and logical thinking - the analogy subtest (AN); tempo characteristics of mental activity, the level of development of operational thinking and operational memory, as well as the characteristics of attention – the arithmetic counting subtest (AS); the ability to transform visual images in space, The level of development of spatial-figurative thinking is the "cubes" (K) subtest.

It is shown that the level of communication abilities increases from low to high neuropsychiatric stability. At the same time, the differences between the indicators of high NPS differ significantly (p<0.017) compared with the average and low severity, the differences between the groups with low and medium resistance are determined at the trend level (0.017<r<0.05) (Table 2).

Table 2

Comparative analysis of discriminant variables, (x±s)

Notes: *p 0.017 <r<0.05 with the "Low NPU" group

** p<0.017 with the "Medium NPU" and "Low NPU" groups

Based on a discriminant model for predicting the level of neuropsychiatric stability of a cadet, the examined person belongs to one of three groups.

The components of the classification functions: variables and coefficients for variables, constants of three LCFS, to determine the prognosis of the level of neuropsychiatric stability of the cadet are presented in Table 3.

Table 3

Classification functions for predicting the level of neuropsychiatric stability of a cadet

The discriminant model has a predictive ability of 68%, while none of the observations from the medium and high NPS groups were misdiagnosed as low NPS. In the low NPS group, 53.5 cadets were correctly identified, which suggests that this model is most effectively able to identify cadets in this group in order to carry out corrective measures with them (Table 4).

Table 4

Accuracy of recognition of the cadet's neuropsychiatric stability forecast (basic calculation)

The algorithm for determining the prediction of the level of neuropsychiatric stability of a cadet is shown in Figure 1.

Fig. 1. Algorithm for determining the prediction of the level of neuropsychiatric stability of a cadet

To determine the forecast of the level of neuropsychiatric stability of a cadet, calculations are performed using all available formulas, the group whose results are the largest and is the desired one. This procedure is standard for linear classification functions.

(LCF-i)max= Low NPU (1), Medium NPU (2), High NPU (3).

Example 1. The following indicators were determined for the subject: An = 9, AC = 9, K = 8. When calculating the formulas LKF-1 = 17.025; LKF-2 = 15.209; LKF-3 = 18.116. The maximum number corresponds to the calculation of the formula for LKF-3, thus, the examined person is predicted to have high neuropsychiatric stability.

Example 2. The following indicators were determined for the subject: An = 6, AC = 7, K = 6. When calculating the formulas LCF-1 = 7.2923; LCF-2 = 9.5829; LCF-3 = 9.3772. The maximum number corresponds to the calculation of the formula for LCF-2, thus, the examined person is predicted to have average neuropsychiatric stability.

Example 3. The following indicators were determined for the subject: An = 4, AC = 4, K = 3. When calculating the formulas LCF-1 = 1.2372; LCF-2 = -0.75; LCF-3 = 0.077. The maximum number corresponds to the calculation of the formula for LCF-1, thus, the examined person is predicted to have low neuropsychiatric stability.

Conclusions.

1. Predictors of the neuropsychiatric stability of military personnel are a combination of indicators of cognitive development: the ability to establish logical relationships between concepts based on analysis and synthesis operations, the level of development of verbal and logical thinking; tempo characteristics of mental activity, the level of development of operational thinking and operational memory, as well as the characteristics of attention; the ability to transform visual images in space, the level of development of spatial-figurative thinking.

2. A model for predicting the level of neuropsychiatric stability was obtained: Wilkes Lambda: 0.95595 approx. F (6.3634)=13.799 p<0.0001, predictive ability of 68%, which allows it to be used in medical and psychological support activities for military university cadets.