The Project aims to assess the long-term risk of trauma-induced stress in young persons. Using non-invasive sound therapy to assess the effects on the vagal nerve via cardiovascular effects and neural activity will provide biofeedback in these individuals.

Background: Some countries have suffered and will continue to suffer great destruction as a result of wars, epidemics, earthquakes, and other natural catastrophes. When individuals are exposed to specific psychological or physical traumas, they can develop stress-related disorders. This can lead to irreversible changes in the autonomic nervous system and cardiovascular disorders. When subjected to a new stress test, traumatized/previously exposed participants may show more pronounced behavioral changes, intolerance, and greater fatigue responses as compared to pre-trauma. To reduce trauma-associated responses from recurring again in the future, especially in young people, it is necessary to take preventive measures. Alternative solutions must be designed for counseling, medication, phytotherapy, etc. This study aims to examine how individuals cope with trauma-related situations using a biofeedback method, which could be developed to manage stress-related coping. The emotional and psychological states of earthquake victims will be assessed using a protocol based on biomedical (neuro-cardiac) signals and the sound of the person's own heart. This sound will be applied at a fixed frequency or in real-time with allostatic auditory stimulation. A resonance stabilizing the autonomic nervous system will thus provide biofeedback to the participants.

Methods: To examine the different states, biological signals will be measured and recorded, such as electrocardiography (ECG), phonocardiography (PCG), electrodermal activity, respiratory rhythm, and near-infrared spectroscopic imaging (fNIRS). Deep learning models will optimally process the collected data and evaluate the results.

Impact: The Project aims to assess the long-term risk of trauma-induced stress in young persons. Using non-invasive sound therapy to assess the effects on the vagal nerve via cardiovascular effects and neural activity will provide biofeedback in these individuals.

Inclusion Criteria:

• 30 earthquake survivor university students between 20 and 25 will participate in the experiment. Participants will be healthy, non-obese men (n=15) and women (n=15). In particular, all participants should have experienced the earthquake disaster in the local region. All participants must be free of any chronic or acute infection, neurological, psychiatric, and/or cardiovascular disease.

Exclusion Criteria:

• They must be non-smokers, have no alcohol or drug addiction, and not be under any medical treatment. Pregnant or breastfeeding women will not be included in the study.