Purchase this article with an account.
Michael J. Holmes, Kasey Soksa, Rick O. Gilmore, Michael Dahlin; What are they looking at? Investigating alternative salient cues in displays of optic flow that may influence infants' orienting. Journal of Vision 2004;4(8):602. doi: 10.1167/4.8.602.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Much is known about adults' perception of self-motion from optic flow, but how these perceptual processes develop in infancy is poorly understood. Current data collected largely using habituation and novelty preference paradigms indicate that young infants are not capable of discriminating heading changes of less than 22 deg. In addition, it seems that little change occurs between the ages of 3 and 6 months. For heading changes larger than 22 deg, it is unclear to what cue infants are responding. For example, it is possible that infants orienting behavior may be influenced by changes in the symmetry of the display rather than by a preference for changes in heading direction. To investigate whether changes in display symmetry influence infants' orienting behavior, three experiments were carried out. In Expt. 1, infants were presented with two adjacent displays of dynamic scenes, which, unlike those used in previous studies, always simulated “off-axis” (i.e. non-zero degree) patterns of optic flow, thereby eliminating change in symmetry as a possible cue. In Expt. 2, short video clips were presented on the display side which depicted changing heading directions, thereby providing additional incentives for infants to orient to the changing side of the display. The results of both studies indicated that infants oriented randomly even when the heading change simulated was up to 90 deg. To address the possibility that infants perceived the split-screen display as a single dynamic image and fixated on the center of the monitor leading observers to randomly assign direction of gaze, a third experiment was conducted. In Expt. 3, babies were habituated to a single display depicting off-axis motion and then shown a novel display simulating a new heading direction that differed by 90 deg . The results showed larger average looking times to the novel display. Thus, we conclude that changes in motion symmetry contribute to but do not fully account for young infants' discrimination of optic flow patterns.
National Science Foundation
This PDF is available to Subscribers Only