Correlation Analysis of Different Measurement Places of Galvanic Skin Response in Test Groups Facing Pleasant and Unpleasant Stimuli

Abstract

The galvanic skin response (GSR; also widely known as electrodermal activity (EDA)) is a signal for stress-related studies. Given the sparsity of studies related to the GSR and the variety of devices, this study was conducted at the Human Health Activity Laboratory (H2AL) with 17 healthy subjects to determine the variability in the detection of changes in the galvanic skin response among a test group with heterogeneous respondents facing pleasant and unpleasant stimuli, correlating the GSR biosignals measured from different body sites. We experimented with the right and left wrist, left fingers, the inner side of the right foot using Shimmer3GSR and Empatica E4 sensors. The results indicated the most promising homogeneous places for measuring the GSR, namely, the left fingers and right foot. The results also suggested that due to a significantly strong correlation among the inner side of the right foot and the left fingers, as well as the moderate correlations with the right and left wrists, the foot may be a suitable place to homogenously measure a GSR signal in a test group. We also discuss some possible causes of weak and negative correlations from anomalies detected in the raw data possibly related to the sensors or the test group, which may be considered to develop robust emotion detection systems based on GRS biosignals.

Towards Human Stress and Activity Recognition: A Review and a First Approach Based on Low-Cost Wearables

“…Table 3 summarizes some recent studies found in the scientific literature about different techniques used to detect stress and sorted in ascending order by publication year. The most analyzed signal was the EDA [60][61][62][63][64][65] which is more efficient when it is obtained from the left-hand fingers [66]. When using EDA features alone, the accuracy obtained was generally high.…”

Feasibility of Electrodermal Activity and Photoplethysmography Data Acquisition at the Foot Using a Sock Form Factor

“…Previous research has already demonstrated a high correlation between simultaneously acquired EDA signals at the hand and foot in healthy individuals [ 11 , 12 , 13 , 14 ]. However, few experimental research actually focused on a sock form factor and/or using e-textiless.…”

“…Most of the work found to date concerning the use of PPG and EDA sensors have focused on the upper limbs, mainly the hands and wrists. However, it is suggested that more remote body locations, such as the feet, could also be used to record PPG [ 10 ] and EDA [ 11 , 12 , 13 , 14 ] signals with comparable quality. Limited research has been conducted on the latter, the reason for which, in this work, the feasibility of Acceleration (ACC), PPG, and EDA data acquisition in a sock form factor are studied, along with the possibility of using e-textiless as the skin-sensor interface.…”

Current trends and opportunities in the methodology of electrodermal activity measurement

“…Vavrinsky et al (Vavrinsky E et al, 2017) developed an "EDA ring" for integration into smart clothes, and Torniainen et al (Torniainen J et al, 2015) demonstrated that a small ring sensor could obtain recordings similar to a laboratory-grade finger EDA measurement, obtaining an average cosine similarity of 83%. For sensor applications integrated into shoes or socks, EDA at the feet correlate well with palmar EDA (Kappeler- Setz C et al, 2013;Kasos K et al, 2019;Sanchez-Comas A et al, 2021). Other skin sites such as the calves may become comparable to the wrists in response frequency, magnitude and correlation, given sufficient hydration time (Kasos K et al, 2019).…”