Abstract
Infants show spontaneous looking preferences for red and blue over yellow and green (Bornstein, 1975). To extend Bornstein's work, we recently tested 3-month-old infants' spontaneous preferences with 4.5 cd/m2 test disks embedded in a 0.45 cd/m2 white surround on a video monitor. Twenty three chromatic stimuli varying in dominant wavelength and colorimetric purity were tested against white (CIE x,y=.33,.33). Infants preferred all chromatic stimuli to white (cf. Adams, 1987) and for each dominant wavelength, preference increased with increasing purity. In general confirmation of Bornstein's results, blue, purple, and red were more strongly preferred than yellow, green, and blue-green.
Might infants' preferences be accounted for by differences in the detectability of stimuli of different dominant wavelengths? To test this hypothesis, we obtained infants' purity detection thresholds for lights of six dominant wavelengths. In general confirmation of the hypothesis, infants' purity detection thresholds were lower for blue, purple and red than for yellow, green and blue-green.
To compare the two data sets quantitatively, we generated infant iso-preference and iso-detection contours in CIE 1931 space. Neither contour was centered at white. Both contours were stretched toward the green region of CIE space, but by different amounts. After normalizing infants' preference data by their purity threshold data, some residual preference differences remained, especially for purple stimuli. We conclude that infants' spontaneous hue preferences are not due solely to variations in detection thresholds.
We have previously shown that infants' spontaneous hue preferences are not due solely to adult-like variations in perceived brightness (Teller et al., VSS 2003) or perceived saturation (Zemach & Teller, VSS 2004). Thus, infants' spontaneous preferences are partially controlled by true preferences for different hues, rather than just by differences in brightness, saturation, or detectability.
Supported by EY07031 to IKZ and EY04470 to DT