Abstract

PINEDA SANCHEZ, José Esael et al. Cardiac Reactivity to Evocation of Stressful Events in a University Population. Acta de investigación psicol [online]. 2023, vol.13, n.2, pp.115-125.  Epub Nov 14, 2023. ISSN 2007-4719.  https://doi.org/10.22201/fpsi.20074719e.2023.2.500.

Heart rate variability (HRV) is used as a reliable physiological signal to assess psychophysiological reactivity to stress. Frequency-domain mathematical analysis of the HRV signal provides metrics that are associated with the performance of the autonomic nervous system. However, the use of measures of central tendency to report global results in different populations underestimates individual differences in the way people react to stress and the clinical importance of this response. The objective of this research was to characterize cardiac reactivity to the evocation of stressful events in a university population. The participants were 94 new psychology students from two universities in Mexico. A psychophysiological stress assessment was performed to estimate cardiac reactivity; the evaluation consisted of the following conditions: 1) Baseline; 2) Evocation of stress; and 3) Recovery. The participants were sitting with their eyes closed and without moving during every single one of the conditions. Four subgroups were created depending on the type of cardiac reactivity to stress. The results indicate a significant consistent decrease in the high-frequency band when evoking stressful events, compared to the low-frequency band. Similar responses were observed between the low-frequency band and the high-frequency band in 60.6% of the cases, suggesting that the antagonistic autonomic balance between the two divisions of the ANS was scarce. According to the autonomic space model and the type of stress reactivity of each student, there were two subgroups characterized by co-activation and co-inhibition modes; and one subgroup characterized by uncoupled response mode. Our findings confirm the viability of the high-frequency band of HRV as a stable indicator of stress reactivity. Likewise, evidence is generated in favor of using evocative stress stimuli to assess physiological reactivity like more personal stressors. Lastly, the importance of specific differences in autonomic activity to characterize the physiological response to stress and its possible clinical utility to propose interventions and select techniques that most effectively benefit vulnerable populations are highlighted.

Keywords : Heart rate variability; Psychophysiological assessment; Stress; Stress reactivity; Autonomic response.