Abstract
Previously, we found that the slant of a hill was overestimated when participants were asked to imagine skating down the hill on a skateboard (Stefanucci, Proffitt, & Clore, 2005). In addition, we showed that vertical extents (or heights) were overestimated when viewed from the top and that this overestimation was correlated with observers' self-reported fear of heights (Stefanucci & Proffitt, 2006). In a series of experiments, we extend the previous work by showing that the perception of height from the top is influenced by manipulations of arousal. Specifically, in Experiment 1, we gave observers either dangerous (highly arousing) or neutral written information about a height. Observers' perceptions of height were then assessed with two measures: visually matched estimates of the apparent distance and visually matched estimates of apparent size (an indirect measure of distance). Observers in the dangerous condition overestimated height more than observers in the neutral condition. In Experiment 2, we replicated these results using a different manipulation of arousal. We presented observers with either arousing or neutral images from the IAPS (International Affective Picture System) standardized library (Lang, Bradley, & Cuthbert, 2005). After viewing the pictures, all observers estimated the height as in Experiment 1. Participants who viewed arousing images overestimated height more than participants who viewed neutral images. The results suggest that arousal plays a role in the overestimation of heights from the top.