A comparison of different electrodermal variables in response to an acute social stressor

We investigated electrodermal activity (EDA) in 130 participants undergoing a shortened version of a novel easy, effective and controlled method to induce stress (the Sing-a-Song Stress Test). We compared skin conductance level (SCL), amplitude and number of skin conductance response peaks with respect to their sensitivity to the known stressor, for different scenarios of interests. EDA increased after stressor-onset for almost all participants. At a group level, the three variables were about equally sensitive. When examining the increase following the stressor with respect to preceding EDA within one individual, peak amplitude was most sensitive. Peak measures were clearly most sensitive in a simulated between-subject scenario (i.e., testing the difference in EDA between stress and non-stress intervals as if data originated from different, stressed and non-stressed groups of individuals). Peaks can be extracted by continuous decomposition (CDA) or through-to-peak analysis (TTP). In all analyses performed, CDA outperformed TTP. We thus recommend CDA peak amplitude for monitoring physiological stress effects in e.g. symbiotic systems.