Faces are visually attractive to both human and nonhuman primates. Human neonates are thought to have a broad template for faces at birth and prefer face-like to non-face-like stimuli. To better compare developmental trajectories of face processing phylogenetically, here, we investigated preferences for face-like stimuli in infant rhesus macaques…

From very early in life, humans can approximate the number and surface area of objects in a scene. The ability to discriminate between 2 approximate quantities, whether number or area, critically depends on the ratio between the quantities, with the most difficult ratio that a participant can reliably discriminate known as the Weber fraction.…

Perceptual narrowing--a phenomenon in which perception is broad from birth, but narrows as a function of experience--has previously been tested with primate faces. In the first 6 months of life, infants can discriminate among individual human and monkey faces. Though the ability to discriminate monkey faces is lost after about 9 months, infants…

Infants were familiarized with plastic animals from one of two categories (land or sea) that were judged similar or variable by adults. Infants were then tested with novel animals from the same or a different category. Thirteen-month-olds in the similar familiarization condition dishabituated to novel animals of a different category and, to a…