Neurophysiological and Autonomic Responses to Acute Physical and Emotional Stress: An EEG Study

This study aims to investigate neurophysiological, autonomic, and subjective responses to different acute physical and emotional stress-inducing conditions using a within-subject repeated-measures design. Participants will complete four experimental conditions: a resting-state baseline, a Cold Pressor Test, a negative autobiographical memory recall task, and an affective picture-viewing task using stimuli selected from the Nencki Affective Picture System (NAPS). The order of the experimental stress conditions will be randomized or counterbalanced to minimize potential order and carry-over effects. Electroencephalographic (EEG) and autonomic activity will be recorded throughout the experimental session. Autonomic measures will include heart rate (HR), heart rate variability (HRV), electrodermal activity (EDA), and skin conductance responses (SCR). Subjective levels of stress, anxiety, and pain will be assessed using visual analogue scales (VAS). Participants will also complete validated psychological measures assessing resilience, perceived stress, and state and trait anxiety, together with the Tower of London task as a behavioral measure of executive planning. The primary objective is to characterize the modulation of EEG alpha-band activity during acute physical stress, with the main comparison focusing on the Cold Pressor Test relative to resting-state baseline. Secondary and exploratory objectives include comparing cortical, autonomic, and subjective responses across experimental conditions and investigating whether individual psychological characteristics and executive functioning are associated with differences in psychophysiological stress responses.