The role of familiarity in a face classification task using thatcherized faces.

Two experiments are reported to test the proposition that facial familiarity influences processing on a face classification task. Thatcherization was used to generate distorted versions of familiar and unfamiliar individuals. Using both a 2AFC (which is "odd"?) task to pairs of images (Experiment 1) and an "odd/normal" task to single images (Experiment 2), results were consistent and indicated that familiarity with the target face facilitated the face classification decision. These results accord with the proposal that familiarity influences the early visual processing of faces. Results are evaluated with respect to four theoretical developments of Valentine's (1991) face-space model, and can be accommodated with the two models that assume familiarity to be encoded within a region of face space.