Configural processing has been considered the major contributor to the face inversion effect (FIE) in face recognition. However, most researchers have only obtained the FIE with one specific ratio of configural alteration. It remains unclear whether the ratio of configural alteration itself can mediate the occurrence of the FIE. We aimed to clarify this issue by manipulating the configural information parametrically using six different ratios, ranging from 4% to 24%. Participants were asked to judge whether a pair of faces were entirely identical or different. The paired faces that were to be compared were presented either simultaneously (Experiment 1) or sequentially (Experiment 2). Both experiments revealed that the FIE was observed only when the ratio of configural alteration was in the intermediate range. These results indicate that even though the FIE has been frequently adopted as an index to examine the underlying mechanism of face processing, the emergence of the FIE is not robust with any configural alteration but dependent on the ratio of configural alteration.

Most current psychological theories of face recognition suggest that faces are stored as multiple 2D views. This research aims to explore the application of 3D face representations by means of a new paradigm. Participants were required to match frontal views of faces to silhouettes of the same faces. The formats of the face stimuli were modified in different experiments to make 3D representations accessible (Experiments 1 and 2) or inaccessible (Experiment 3). Multiple 2D view-based algorithms were not applicable due to the singularity of the frontal-view faces. The results disclosed the application and adaptability of 3D face representations. Participants can readily solve the tasks when the face images retain the information essential for the formation of a 3D face representations. However, the performance substantially declined when the 3D information in faces was eliminated (Experiment 3). Performance also varied between different face orientations and different participant groups.

It has been found that humans not only tend to avoid the middle routes and prefer the peripheral routes among multiple choices, but also rely on the 'initial segment strategy' to select the route. In this paper, we propose a new heuristic which humans apply during route selection: Participants prefer the route whose initial direction lies in the direction of their final destination, while avoiding the route whose initial direction does not. Four maps were designed. The pathways, on different maps, constituted a parallelogram, a rectangle and a square. Pedestrians were instructed to select a route from an origin to a destination on one of the maps. The results confirm the application of the newly proposed heuristic. Other possible factors, such as handedness, route angles and occurrence of turns were excluded. Moreover, the heuristics of deferring decision and relying on initial straightness are not supported.