Biofeedback with heart sounds following a traumatic event.

BACKGROUND: Some countries have experienced and may continue to experience severe devastation due to wars, epidemics, earthquakes, and other natural catastrophes. When individuals are exposed to specific psychological or physical traumas, they can develop stress-related disorders, which can lead to irreversible changes in the autonomic nervous system and the development of cardiovascular disorders. When subjected to a new stress test, traumatized participants or those previously exposed to trauma may show more pronounced behavioral changes, intolerance, and greater fatigue responses than before trauma exposure. To reduce the recurrence of trauma-associated responses, particularly among young people, it is necessary to implement preventive measures. Alternative approaches, including counseling, medication, phytotherapy, and other interventions, need to be developed. This study aims to examine how individuals cope with trauma-related situations using a biofeedback method that could be developed to manage stress-related responses. The emotional and psychological states of earthquake victims will be assessed using a protocol based on biomedical (neurocardiac) signals and the sound of the participants' hearts. This sound will be delivered at a fixed frequency or in real time with allostatic auditory stimulation. This approach aims to induce a resonance that stabilizes the autonomic nervous system by providing biofeedback to participants. METHODS: To examine different states, biological signals will be measured and recorded, including electrocardiography (ECG), phonocardiography (PCG), electrodermal activity (EDA), respiratory rhythm, and functional near-infrared spectroscopy (fNIRS). Statistical methods and deep learning models will be applied to process the collected data optimally and evaluate the results. IMPACT: This study aims to assess the medium- to long-term risk of trauma-induced stress among young individuals. The use of non-invasive sound therapy to evaluate its effects on the vagal nerve through cardiovascular responses and neural activity may provide biofeedback for these individuals. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/study/NCT06919055. The trial has been registered on www.ClinicalTrials.gov with registration number NCT06919055 on 17 March 2025 with the title "Biofeedback with Heart Sound Following Trauma (ALLOSTAT0001)."