id_1020. EVOLUTIONARY THREAT SUPERIORITY? ENHANCED EVEN-RELATED POTENTIALS IN RESPONSE TO THREATENING ANIMALS COMPARED TO EMOTIONAL FACES
Pouria Motaghi1, Rob van Lier2, Rob van der Lubbe3,4, Marijtje L. A. Jongsma1
1 Behavioural Science Institute, Radboud University, Thomas van Aquinostraat 4, 6525 GD, Nijmegen, The Netherlands
2 Donders Institute for Brain, Cognition, and Behaviour, Radboud University, Kapittelweg 29, 6525 EN, Nijmegen, The Netherlands
3 Laboratory of Vision Sciences and Optometry, Faculty of Physics and Astronomy, Adam Mickiewicz University, Uniwersytetu Pozna´nskiego 2, 61-614, Poznan, Poland
4 Faculty of Behavior, Management and Social Sciences, University of Twente, Drienerlolaan 5, 7522 NB, Enschede, The Netherlands
INTRODUCTION: Threat processing occurs rapidly, with responses emerging as early as 45 ms. EEG studies show that threat modulates event-related potential (ERP) components such as P1, N170, and EPN, reflecting early attention and emotional processing. Emotional facial expressions and threatening animals are widely used to study fear processing. However, a direct comparison between these two types of stimuli at the within-participant level has received little attention in the literature.
AIM(S): This study directly compares pictures of negative facial expressions and threatening animal pictures to evaluate and compare the threat response reflected on the ERPs between these two stimulus sets to determine which stimuli are most suitable to study threat processing.
METHOD(S): Forty healthy adults completed an EEG experiment involving passive viewing of faces and animals. Participants viewed 200 face pictures (angry, fearful, neutral, and inverted neutral) and 200 animal pictures (spider, snake, bird, and inverted bird), followed by a scrambled version of the animal pictures to control for the low-level visual features. A 64-channel EEG setup was used for the extraction of ERP components from four latency windows (P120, N170, P200, and EPN). We used repeated-measures ANOVA to assess the threat response by analyzing mean ERP amplitudes for each component.
RESULTS: ERP analyses revealed robust threat effect for animal stimuli across all components, with snake and spider pictures eliciting more negative amplitudes than birds, particularly over parietal and parieto-occipital regions. In contrast, facial expressions showed limited threat effects, with small differences emerging mainly in later components and specific regions of interest (ROIs).
CONCLUSIONS: Our findings show that threatening animal pictures evoke a stronger and earlier response to threat than emotional facial expressions. These results suggest that animal stimuli may provide a stronger and more reliable tool for studying rapid threat processing in EEG studies.
FINANCIAL SUPPORT: This research has been conducted within a self-funded PhD project.