Testing location invariance of the flashed face distortion effect

Abstract

Spatially aligned faces presented in a continuous stream in the periphery appear distorted and grotesque. This flashed face distortion effect (“FFDE”) was first reported over 10 years ago, yet little is known about the underlying mechanisms. Here we investigate whether the FFDE persists across visual field locations when there is a change in position. Face streams were presented at one location for several seconds and then either remained at the same location, or were shifted to a new location, either across visual half-fields (Experiment 1) or within the same visual half-field (Experiment 2). We assessed the perceived illusion magnitudes continuously throughout each trial using a joystick as a response device and found that the illusion decreased significantly when the location changed. In the third experiment we added a control condition that did not elicit an illusion and found that the decrease in reported distortions for location-shift trials was of the same magnitude as this baseline condition. Together, our results suggest that the FFDE may be bound to retinotopic locations, at least when location changes are relatively large.