Low-level Abilities

Introduction We can learn a lot by studying the development of object perception and recognition. For example, creating a developmental timeline of perceptual abilities can help to show which tasks are most easily learned and performed. In turn, this ordering can be used to break a complex perception task into a series of simpler components. Studies often reveal impressive perceptual skills in infants, despite physical limitations and a lack of world experience. Correlating the development of these perceptual abilities with that of physical structures in the brain can suggest new relationships between structure and function. And in a clinical setting, knowledge about the normal progression of perceptual development gives a rubric for judging deviations. In addition, such developmental studies “[reveal] something about adults: our visual processes, visual experiences, and visual knowledge.” (Spelke, 1995). Neonates (infants from a few hours to a month old) have certain innate predispositions. They prefer stimuli that are: patterned, high in contrast, in a fronto-parallel orientation (i.e. straight-on rather than angled view), in a horizontal (rather than vertical) orientation, face-like, 3dimensional, curvilinear (i.e. rounded instead of straight-edged), and of an “optimal” size (generally not large enough to eclipses the field of view). Infants also appear, according to Haith, (1980) to follow certain “rules for exploration”: If awake and alert and light not too bright, open eyes. If in darkness, maintain a controlled, detailed search If in light with no form, search for edges by relatively broad jerky sweeps of the visual field. If an edge is found, terminate broad scan and stay in vicinity of that edge.