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

Summary

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.

Conditions

• Stress
• Acute Stress

Interventions

BEHAVIORAL

Cold Pressor Test

Participants will immerse one hand in an ice-water bath and will be instructed to maintain the immersion for as long as tolerable, up to a maximum of three minutes. Participants may withdraw their hand at any time if the stimulation becomes intolerable. The actual duration of hand immersion will be recorded as an index of pain tolerance. EEG and autonomic activity will be continuously recorded during the task.

BEHAVIORAL

Negative Autobiographical Memory Recall

Participants will be instructed to select a personally painful or distressing autobiographical memory and focus on its emotional and experiential aspects for three minutes while seated with their eyes closed. No specific autobiographical event will be suggested by the researcher. EEG and autonomic activity will be continuously recorded during the task.

BEHAVIORAL

Affective Picture-Viewing Task

Participants will view negative and neutral images selected from the Nencki Affective Picture System (NAPS). Each trial will consist of a 10-second fixation period followed by a 30-second image presentation. Images will be presented in randomized order while EEG and autonomic activity are continuously recorded.

Sponsors & Collaborators

• University of Padova

  collaborator OTHER

• San Raffaele University Hospital, Italy

  collaborator OTHER

• IRCCS San Raffaele

  collaborator OTHER

• University of Pavia

  lead OTHER

Study Design

Allocation

NA

Purpose

BASIC_SCIENCE

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-08-01

Primary Completion

2026-08-15

Completion

2026-08-15

Countries

• Italy

Study Locations