Event-Related potentials in visual attention to threatening and fearful Stimuli: A systematic review

This systematic review aimed to synthesize event-related potential (ERP) findings relating to the processing of threat-related visual stimuli across different stimulus categories. We included peer-reviewed, empirical studies published between 2000 and 2024 which reported ERP data in response to visual, threat-related stimuli in adult human participants. We excluded studies using non-visual modalities or non-ERP outcomes. The systematic search of PubMed and Web of Science was conducted on 1 August 2024. Study selection was performed independently by two reviewers. We narratively synthesized ERP results by stimulus type and component. Twenty-four studies met the inclusion criteria, comprising samples of healthy participants. Most of the studies used facial expressions as stimuli, while others employed images of animals (e.g. snakes and spiders), modern threats (e.g. guns, knives), or environmental scenes. Early ERP components (e.g. P1, N1, and EPN) were modulated by biologically salient stimuli, which suggests rapid attentional capture. Later components (e.g. LPP) reflected sustained engagement and cognitive evaluation, with modulation patterns varying according to stimulus type, cognitive load and participant characteristics. The type of stimulus may affect ERP markers of threat processing. The findings emphasize the value of ERPs as precise indicators of emotional attention and suggest their potential as biomarkers in clinical research.