Simultaneous color contrast in 4-month-old infants

The present paper addresses the question of simultaneous color contrast in 4-month-old human infants. A temporal modulation paradigm was employed for infant testing. In this paradigm, infants viewed two test disks presented side-by-side: one of unchanging chromaticity (static) and another of the chromaticity varied in time (temporally modulated). The test stimuli were embedded in a surround that was either static or temporally modulated in phase with the modulated test stimulus. The temporally modulated test stimuli were chosen in such a way as to appear static to adults when viewed in the temporally modulated surround. On the basis of the observation that infants prefer to look more at flickering stimuli, the prediction is that, if infants have adult-like simultaneous color contrast, their preference for the temporally modulated stimulus should decrease and their preference for the static stimulus should increase when the surround is also temporally modulated as described. In concordance with this prediction, a significant increase in preference for the temporally static stimuli was observed with the introduction of temporal modulation in the surround. The data are consistent with the conclusion that infants as young as 4 months of age have simultaneous color contrast.