Acta Informatica Pragensia X:X | DOI: 10.18267/j.aip.305135

FearTherapy: Assessing the Impact of Therapeutic Games in Virtual Environments through Physiological State Measurements

Zoltán Balogh ORCID...1,2, Kristián Fodor ORCID...2, Martin Magdin ORCID...1,3, Jaroslav Reichel ORCID...1, József Kopják ORCID...2, ©tefan Koprda ORCID...1, Martin Polák ORCID...4
1 Faculty of Natural Sciences and Informatics, Constantine the Philosopher University Nitra, Nitra, Slovakia
2 Kándó Kálmán Faculty of Electrical Engineering, Óbuda University, Budapest, Hungary
3 Faculty of Economics, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
4 GAMETHERAPY s.r.o., Nitra, Slovakia

Background: Virtual reality (VR) integrated with internet of things (IoT) wearable devices offers innovative approaches to mental health interventions by enabling real-time physiological monitoring during immersive therapeutic experiences.

Objective: This study aims to evaluate the effectiveness of VR therapeutic games in identifying and measuring emotional responses through physiological signals (heart rate and galvanic skin response) and to classify these responses using machine learning.

Methods: We conduct experiments with 103 participants (aged 6–57 years) using FearTherapy, a custom VR game featuring interactions with four animals (Hermit, Bee, Wolf, Spider). Physiological data are collected using Samsung Galaxy Watch 5 for heart rate and Arduino Uno with a galvanic skin response (GSR) sensor. After preprocessing, 55 valid sessions remain for analysis. Individual baseline heart rate values are established and random forest classification with grid search optimization and 10-fold cross-validation is performed.

Results: GSR emerges as the most influential feature for classifying emotional states, followed by heart rate difference and baseline reference values. Highest emotional arousal occurs during Spider and Bee interactions. The random forest model achieves 69% cross-validation accuracy and 81% test set accuracy. The model performs well overall but encounters challenges distinguishing Bee from Hermit and Wolf from Spider, suggesting overlapping emotional states.

Conclusion: VR therapeutic games combined with IoT physiological monitoring can effectively measure and classify emotional responses. The findings support development of personalized, emotionally adaptive therapeutic interventions for anxiety and phobia treatment, emphasizing the importance of individualized baseline measurements for accurate emotional state assessment.

Keywords: Virtual reality; Sensory network; Internet of things; Therapeutic game; Machine learning; Fear measurement; Physiological monitoring; Galvanic skin response; Heart rate.

Received: September 23, 2025; Revised: January 27, 2026; Accepted: February 2, 2026; Prepublished online: March 29, 2026 

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