Throughout human evolutionary history, snakes have been associated with danger and threat. Research has shown that snakes are prioritized by our attentional system, despite many of us rarely encountering them in our daily lives. We conducted two high-powered, pre-registered experiments (total N = 224) manipulating target prevalence to understand this heightened prioritization of threatening targets. Target prevalence refers to the proportion of trials wherein a target is presented; reductions in prevalence consistently reduce the likelihood that targets will be found. We reasoned that snake targets in visual search should experience weaker effects of low target prevalence compared to non-threatening targets (rabbits) because they should be prioritized by searchers despite appearing rarely. In both experiments, we found evidence of classic prevalence effects but (contrasting prior work) we also found that search for threatening targets was slower and less accurate than for nonthreatening targets. This surprising result is possibly due to methodological issues common in prior studies, including comparatively smaller sample sizes, fewer trials, and a tendency to exclusively examine conditions of relatively high prevalence. Our findings call into question accounts of threat prioritization and suggest that prior attention findings may be constrained to a narrow range of circumstances.

Department of Economy and Management Ambis University Prague Czech Republic

Department of Psychology New Mexico State University Las Cruces USA

Faculty of Science Charles University Prague Czech Republic

Institute of Psychology University of Pécs 6 Ifjusag Street Pécs 7624 Baranya Hungary

School of Psychology University of Southampton Southampton UK

Szentágothai Research Centre University of Pécs Pécs Hungary

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Hooding cobras can get ahead of other snakes in the ability to evoke human fear

Editorial: Towards an understanding of the cognitive mechanisms involved in threat processing and perception

Imprint of ancestral and modern threats in human mind - experience of fear, disgust, and anger