Electrodermal Responses in Context Dependent Fear

Presenter: Ellie Diederich

Research Category: Physical and LIfe Sciences
College: College of Science
Major(s): Psychology
Graduation Date: 2021
Additional Authors: Yiyu Wang, Kieran McVeigh

Do different situations evoking fear experiences have the same physiological correlates? The current study aims to examine how psychophysiological activity, specifically, electrodermal activity (EDA) may vary across fear experiences under different situations. Participants (n=14) watched 36 point-of-view videos depicting heights, social situations, and spiders, and reported subjective fear experiences for each video while undergoing fMRI. Simultaneous EDA was collected from the palm. Skin conductance responses (SCRs) for frequency and relative magnitude change during each video watching period were calculated. First, subject-level regressions showed that fear ratings were positively related to both SCR magnitude (M = 0.22, SD = 0.27, t(13) = 2.99, p < 0.02,) and frequency (M = 0.22, SD = 0.18, t(13) = 4.6, p < 0.01). Next, the one-way ANOVA analysis revealed a significant effect of situations (frequency: F(2,39) = 16.36, p < 0.01; magnitude: F(2,39) = 5.63, p < 0.01). Post-hoc analyses showed that the magnitude and frequency of SCRs significantly differed between heights and social situations (t(13) = 4.28, p < 0.01; t(13) = 2.73, p < 0.02), and heights and spiders (t(13) = 4.74, p < 0.01; t(13) = 2.83, p < 0.01). There was no difference between spiders and social situations (t(13) = 0.49, p = 0.63; t(13) = 0.13, p = 0.90). The results indicate that different physiological patterns are associated with fear experiences under different situations. The findings suggested that physiological responses to fear experiences are context dependent.