Changing face contours reduces the inversion effect and overall recognition performance

This paper investigates how manipulating the face contour would systematically influence the face inversion effect (i.e., better recognition performance for upright vs inverted upside-down faces) and overall face recognition. Experiment 1 (n=144) addressed the question of whether manipulating the face contour would affect the inversion effect for scrambled faces which have disrupted configural information. Our results revealed that blurring the face contour significantly reduced the inversion effect by means of impaired performance for upright scrambled faces. Experiment 2a (n=144) and Experiment 2b (n=144) examined how either blurring the contour or replacing it with a new contour would influence the inversion effect for normal faces. These results confirmed a reduction of the inversion effect mainly due to impaired performance for upright faces. A reduction in overall recognition performance was also recorded for normal faces with a manipulated contour. Experiment 3 (n=144) manipulated the contour of New Thatcherized faces which suffer from partial configural information disruption. The results revealed no influence on the inversion effect but a significant reduction in overall recognition performance. Taken together, our results suggest that face contour information can have an impact in influencing both the inversion effect and overall recognition performance.