757: Autonomic Responses to Heat Pain: Interplay Between Electrodermal Activity and Psychological Factors

Topic: Experimental (Non-clinical) Human Studies
Subtopic: Pain Category (ICD-11), Other acute pain category, Psychology, Developing methodology/technology, Assessment and Measurement of Pain/Nociception

Background and Aims: Pain is a multidimensional experience explained by the biopsychosocial model, involving biological, psychological, and social factors [1,2]. Current pain assessment relies mainly on subjective self-report tools, which have limitations, particularly in non-verbal populations [3]. This has increased interest in objective measures based on, e.g. autonomic nervous system responses, including electrodermal activity (EDA), heart rate, and respiration, with EDA considered one of the promising biomarkers [4–6].
This study aims to examine whether smartwatch-derived EDA can objectively reflect pain intensity during experimental thermal heat stimulation and to investigate the relationship between psychological factors (catastrophizing, depression, anxiety, and stress) and EDA responses.

Methods: Twenty healthy adults (10 males, 10 females; aged 18–35) participated. EDA was continuously recorded using a smartwatch on the non-dominant wrist. Thermal pain was induced on the dorsal dominant hand using five heat pulses to 47°C (20 seconds each) with 10 s intervals at 32°C. Pain intensity was rated every 10 s using a Numeric Rating Scale (0–10). Psychological factors were assessed using the Pain Catastrophizing Scale (PCS) and the Depression, Anxiety, and Stress Scale (DASS-21). Relative EDA was analyzed across the baseline, pain, and post-pain phases (3 minutes each) using the area under the curve (AUC).

Results: EDA increased during stimulation, peaking in the post-pain phase (20-40 s after the end of pain stimulation) and then gradually declining without returning to baseline. AUC EDA was higher during pain than baseline, and highest during post-pain compared to both (p<0.001). Pain ratings positively correlated with depression (r=0.674, p<0.01), stress (r=0.505, p<0.05), and helplessness (r=0.462, p<0.05), but not with EDA. Individuals with high magnification showed higher EDA during the pain phase (p<0.01) and larger increases from baseline to pain (p<0.05) compared to low-magnification subjects. Greater post-pain changes relative to baseline were observed in high depression and high helplessness individuals (p<0.01).

Conclusions: This study suggests that EDA measured via wearable technology is sensitive to experimentally induced thermal pain and reflects clear increases in autonomic responses. However, the lack of association between EDA and subjective pain ratings suggests that physiological arousal and perceived pain intensity may represent partly distinct processes. Psychological factors, particularly depression, stress, and catastrophizing (magnification and helplessness), were related to both pain intensity and EDA responses. Overall, the findings support EDA as a promising objective pain biomarker, while highlighting the need to incorporate psychological factors and multimodal approaches to improve the accuracy and interpretation of physiological pain assessment.

References: 1. Gatchel, R. J., Peng, Y. B., Peters, M. L., Fuchs, P. N. & Turk, D. C. The biopsychosocial approach to chronic pain: scientific advances and future directions. Psychol. Bull. 133, 581 (2007).
2. Bolton, D. A revitalized biopsychosocial model: core theory, research paradigms, and clinical implications. Psychol. Med. 53, 7504–7511 (2023).
3. Karcioglu, O., Topacoglu, H., Dikme, O. & Dikme, O. A systematic review of the pain scales in adults: which to use? Am. J. Emerg. Med. 36, 707–714 (2018).
4. Bhatkar, V., Picard, R. & Staahl, C. Combining electrodermal activity with the peak-pain time to quantify three temporal regions of pain experience. Frontiers in Pain Research 3, 764128 (2022).
5. Camacho-Navas, C., Li, L., Poply, K., Mehta, V. & Kyriacou, P. Pain assessment using physiological responses/markers in different types of pain: a scoping review. NPJ Digit. Med. (2026).
6. Semiz, B., Hancioglu, Ö. K. & Şahin, R. S. Pain assessment and determination methods with wearable sensors: a scoping review. Med. Biol. Eng. Comput. 1–18 (2025).

Presenting Author: Giulia Erica Aliotta
Submitting Author: Giulia Erica Aliotta

Senior Author: Lars Arendt-Nielsen

IASP 2026 Global Year theme of Neuropathic Pain: No

• Laura Petrini: PhD - Department of Health Science and Technology, School of Medicine, Aalborg University, Denmark
• Benedetta Riboldi: M.Sc. - Department of Pharmacological and Biomolecular Sciences “Rodolfo Paoletti”, Universitá degli Studi di Milano, Italy - Department of Health Science and Technology, School of Medicine, Aalborg University, Denmark
• Natalia Fernandez Sanchez: M.Sc. - Department of Health Science and Technology, School of Medicine, Aalborg University, Denmark - Department of Physical Therapy, University of Granada, Spain
• Yacine Hadjat: PhD - Dubai Health Innovations, Mohammed Bin Rashid University of Medicine and Health Sciences (MBRU), Dubai, United Arab Emirates
• Lars Arendt-Nielsen: PhD - Department of Health Science and Technology, School of Medicine, Aalborg University, Denmark - Department of Gastroenterology & Hepatology, Mech-Sense, Clinical Institute, Aalborg University Hospital, Denmark - Steno Diabetes Center North Denmark, Clinical Institute, Aalborg University Hospital, Aalborg, Denmark