Inbound friend or foe: how motion bistability is resolved under threat

Abstract Anxiety prepares us to deal with unpredictable threats, such as the approaching of an unknown person. Studies have shown our innate tendency to see approaching motion in ambiguous walkers in what was termed facing-the-viewer (FTV) bias. Here we investigated if anxiety states further contributed to this bias, hypothesizing that such states would increase overall FTV biases. Throughout three Experiments, we asked participants to judge the motion direction of ambiguous point-light walkers and measured their respective FTV biases under safe and anxiety-related conditions induced via imagery (Experiment 1), screaming sounds (Experiment 2), and threat of shock (Experiment 3). Across all experiments, we showed that anxiety does not affect our tendency to perceive an approaching behavior in ambiguous walkers. Based on our findings, and the discrepancies found in the literature, we emphasize the need for future studies to paint a clearer picture on the nature and aspects capable of affecting this bias.