Perception of three-dimensional shape specified by optic flow by 8-week-old infants

Abstract

Sensitivity of 8-week-old infants to optical flow specifying the shape of a three-dimensional object was assessed. Infants viewed kinetic random-dot displays that specified three-dimensional cubes. The cubes were identical except for the presence or absence of an interior comer. Half of the infants viewed the full display. The other half viewed the central region of the displays, where the flow specifying the presence or absence of the comer differed. Infants in the full-view condition looked significantly longer to a novel cube than to the familiar cube following habituation. In contrast, infants in the partial-view condition looked equally to the novel and familiar cubes, ruling out the possibility that infants who viewed the full displays merely discriminated differences in motion in the central region of the two displays. These findings suggest that infants as young as 8 weeks perceive three-dimensional object shape from optic flow.Perception of the world based on motion has occupied perceptual psychologists for a number of decades (see Braunstein, 1962, for a review). Pioneering work by Helmholtz (1909Helmholtz ( /1924 suggested that the differential motion ofobjects located at different distances was an effective cue to depth, and informal experiments conducted by Mach (1886/1959) may have been the first in which perception of structure from motion was explored. Wallach and O'Connell (1953) performed the first formal experiments on the perception of three-dimensional shape from motion, which they called the kinetic depth effect. In their work, they found that a static shadow of an object projected onto a screen was perceived as a flat twodimensional design. However, when the object rotated, the deforming contours were perceived accurately as a three-dimensional object. Gibson (1950Gibson ( , 1966 placed perception based on motion-carried information at the center of his new theory and highlighted its importance for veridical perception. Motion-carried information is viewed widely as an effective source of information for spatial layout. Moreover, those studying the development ofperceptual processes have found that early in life, humans are responsive to motion-carried information. In the present study, we investigated 8-week-old infants' ability to

The influence of training views on infants' long‐term memory for simple 3D shapes

“…Kellman imposed a half-second delay between static images to eliminate apparent motion cues, so that only the information available from a single view was present at any time, in both the 15 and 60 conditions of his study. The suggestion that information from smooth motion is an integral part of the infant's perception of 3D shape is also supported by a finding by Arterberry and Yonas (2000) that infants are capable of perceiving 3D shape from motion information alone. It may be possible that infants could develop a percept of a 3D shape from a set of distinct, but closely related views (e.g., of 5 steps), without motion information.…”

Dorsal stream development in motion and structure-from-motion perception

“…Behavioural developmental studies show that SFM can be detected by infants (Arterberry and Yonas, 2000) and reach a mature level at the age of 7 (Parrish et al, 2005). Dependent on the perceptual features and the attentional demands during the task, however, developmental differences occur even until adolescence (Schrauf et al, 1999).…”

“…This idea was based on findings that perception of biological motion or structure from motion develops at about the same age as the detection of coherent motion. For example, 3-6-month-old infants can already detect SFM (Arterberry and Yonas, 1988;Arterberry and Yonas, 2000;Kaufmann-Hayoz et al, 1986;Yonas et al, 1987). Others, however, suggested that a third area, probably in the posterior, superior parietal cortex, needs to be activated that binds both motion and shape processing areas (Zeki, 2001).…”

Four‐Month‐Olds' Discrimination of Optic Flow Patterns Depicting Different Directions of Observer Motion

“…At an age when infants can discriminate some aspects of object form from motion (Arterberry & Yonas, 2000;Bertenthal et al, 1987;Kellman, 1993), blink, or make backward head movements in response to approaching textures (Nañez & Yonas, 1994), and discriminate between objects and apertures defined by motion and texture information (Schmuckler & Li, 1998), they appear to have only limited capacities to discriminate between optic flow displays that depict changes in the direction of simulated self-motion. The combined results from three studies using two different experimental paradigms strongly suggest that the minimum heading angle 4-month-olds can reliably discriminate is at least 32°.…”