Comprehensive Assessment of Combatants' Psychological and Psychophysiological State in Exposure Therapy of Post-Traumatic Stress Disorder Using Virtual Reality.

The aim of the study was to develop the rehabilitation technology that enables the monitoring of psychophysiological stress markers during exposure therapy of post-traumatic stress disorder in combatants using virtual reality (VR).

Materials and methods: The study involved 69 men: 31 combatants (mean age - 35.61±9.13 years) and 38 healthy research subjects - a control group (mean age - 24.68±5.71 years) not engaged in active combat.Post-traumatic stress disorder was diagnosed using Structured Clinical Interview for DSM and Mississippi Scale.We suggested an original hardware and software system for exposure therapy in VR. Stimulus material included a number of virtual scenes: three combat scenes and a non-combat one.Heart rate variability was recorded to control a patient's state during the session. As markers of stressogenic situations we used CS-index (suggested by S.V. Bozhokin), as well as the indices of functional reserve and tension degree of the regulatory systems (according to R.M. Baevskiy).

Results: There were revealed three main responses on VR scenes with an original content. The three variants were called as follows: "anxious", "neutral", and "inverse". The suggested methodology enables to continuously monitor psychophysiological parameters during a certain session, and analyze their dynamics within a therapy course.Using calculated indicators by Baevsky makes it possible to classify combatants by adaptive potential at the beginning and at the end of the exposure therapy course in VR; make use of online-control of a patient's functional state in virtual environment, and create conditions for controlled information influence (CS-index by Bozhokin).The preliminary results presented in the study are promising regarding the possibility to choose a personalized program of rehabilitation measures for each response type using a developed hardware and software system. Biological feedback on heart rate variability included in hardware and software system will contribute to train and harness a patient's habit of an operative independent correction of the patient's state.