How Looking at Someone You Don’t Know Can Help You Recognize Someone You Do

Abstract

Adaptation to faces has been shown to influence judgments of many different features of subsequently viewed faces. For example, after viewing a face that has had its internal features compressed, subjects report that the features of a normal face seem unnaturally expanded (Webster & MacLin, 1999). Recent work has extended these findings to identity, showing that the judgments of the identity of a neutral face can be biased by adaptation to another face (Leopold, D., O'Toole, A., Vetter, T., & Blanz, V., 2001). These results have been interpreted as supporting face- space models of recognition where faces are coded with respect to the prototype. While fascinating, these results require extensive training and depend on participants’ subjective reports. We present an objective method for demonstrating that adaptation can affect identity judgments without extensive training in the lab thus supporting the notion of identity based aftereffects. However, the fact that our stimuli are chosen without consideration of a face space suggests that there may be alternative mechanisms underlying face representation and adaptation that do not rely on a prototype.