Recognition times for rotated normal and "Thatcher" faces.

To test whether face recognition is more disrupted by inversion than is the recognition of nonface stimuli and that an inverted Thatcher face is much less likely to be noticed as different than an upright one, reaction times were measured for recognizing "normal" and "abnormal" (Thatcher) faces (created by inverting the eyes and mouth relative to the rest of the face) presented at six orientation angles from upright. Over-all, reaction time of 22 students increased monotonically as faces were rotated away from upright; however, the orientation effect was essentially the same for both types of faces, indicating processing of faces is not qualitatively different from the processing of other types of stimuli. These data allow the inference that the subjects mentally rotated the internal features of eyes and mouth to upright and then judged whether the face was normal or abnormal.