Light is the origin of vision. The pattern of shading reflected from object surfaces is one of several optical features that provide fundamental information about shape and surface orientation. To understand how surface and object shading is processed by birds, six pigeons were tested with differentially illuminated convex and concave curved…

Contour interpolation is a perceptual process that fills-in missing edges on the basis of how surrounding edges (inducers) are spatiotemporally related. Cognitive encapsulation refers to the degree to which perceptual mechanisms act in isolation from beliefs, expectations, and utilities (Pylyshyn, 1999). Is interpolation encapsulated from belief?…

Psychological studies of face recognition have typically ignored within-person variation in appearance, instead emphasising differences "between" individuals. Studies typically assume that a photograph adequately captures a person's appearance, and for that reason most studies use just one, or a small number of photos per person. Here we show that…

Recent studies showed that stimuli are evaluated more favourably when they are perceived to capture others' attention, an effect coined "mimetic desire". The aim of the present research was to examine the combined role of Need for Cognition and target's facial trustworthiness in this effect. Participants saw movie excerpts of trustworthy and…

Categorical perception (CP) is said to occur when a continuum of equally spaced physical changes is perceived as unequally spaced as a function of category membership (Harnad, S. (Ed.) (1987). Psychophysical and cognitive aspects of categorical perception: A critical overview. Cambridge: Cambridge University Press). A common suggestion is that CP…

We report three experiments that investigate whether faces are capable of capturing attention when in competition with other non-face objects. In Experiment 1a participants took longer to decide that an array of objects contained a butterfly target when a face appeared as one of the distracting items than when the face did not appear in the array.…

The preparation of eye or hand movements enhances visual perception at the upcoming movement end position. The spatial location of this influence of action on perception could be determined either by goal selection or by motor planning. We employed a tool use task to dissociate these two alternatives. The instructed goal location was a visual…

Two experiments investigated categorical perception (CP) effects for affective facial expressions and linguistic facial expressions from American Sign Language (ASL) for Deaf native signers and hearing non-signers. Facial expressions were presented in isolation (Experiment 1) or in an ASL verb context (Experiment 2). Participants performed ABX…

How does an observer decide that a particular object viewed at one time is actually the "same" object as one viewed at a different time? We explored this question using an experimental task in which an observer views two objects as they simultaneously approach an occluder, disappear behind the occluder, and re-emerge from behind the occluder,…

Figure/ground assignment--determining which part of the visual image is foreground and which background--is a critical step in early visual analysis, upon which much later processing depends. Previous research on the assignment of figure and ground to opposing sides of a contour has almost exclusively involved static geometric factors--such as…

A paradigm was designed to study how infants identify live faces. Eight- to 21-week-old infants were seated comfortably and were presented an adult female, dressed in a white laboratory coat and a white turtle neck sweater, until habituation ensued. The adult then left the room. One minute later either she or an identically garbed confederate…