Revisiting the perception of upside-down faces

In two experiments, the effect of orientation on face perception was assess ed Using a scale from 1 (normal) to 7 (bizarre), participants rated normal, unaltered faces and faces in which changes had been made to spatial-relati onal properties (eyes and mouth inverted or relative position of the eyes a nd mouth altered) or to component properties (eyes whitened and teeth black ened). For unaltered and component-distortion faces, bizarreness ratings in creased linearly as orientation increased from 0 degrees to 180 degrees. Fo r spatial-distortion faces, a discontinuity in the function relating orient ation and bizarreness was in evidence between 90 degrees and 120 degrees. T he results provide support for the view that there is a qualitative differe nce in the processing of upright and inverted faces due to the disproportio nate effect of inversion on the encoding of spatial-relational information.