Orientation dependence of the orientation-contingent face aftereffect.

Prolonged exposure to upright and inverted female and male faces produces opposite effects on subsequent judgments of the sex of faces depending on their orientation. We show that the magnitude of this orientation-contingent gender aftereffect can be predicted from simple aftereffects induced separately at the same orientations. The contingent aftereffect can also be induced in faces tilted 90 degrees to the right and left, eliminating any difference in face-processing strategy that may be in operation with upright and inverted faces. This suggests that neurons employing a single face encoding strategy can be activated in an orientation-specific manner.