Infant Color Vision Research Articles

Infant color vision: The effect of test field size on rayleigh discriminations

The capacity of 1- and 3-month-old infants to discriminate 589 nm and 650 nm test fields from a 589 nm surround was tested using the forced-choice preferential looking (FPL) technique. The size of the test field ranged from 1 to 8°. Test field size strongly influenced the infants' performance. One-month-olds discriminated 8 and 4° (but not 2°) 650 nm fields from the 589 nm surround; 3-month-olds discriminated 4 and 2° (but not 1°) 650 nm fields from the 589 nm surround. The dependence of performance on field size suggests that infants' discrimination failures with small fields are due to immaturities of spatial processing or postreceptoral chromatic mechanisms, rather than to any absence or anomaly of receptor types. In addition, adult subjects rated the hue, brightness, and salience of the test stimuli at 0, 26, 52, and 78° eccentricity. The analogy often made between infant vision and adult peripheral vision is discussed in relation to these data.

Scotopic vision, color vision, and stereopsis in infants.

Infants as young as 1 month postnatal have scotopic spectral sensitivity closely resembling the CIE standard curve and thus appear to have a functional, rhodopsin-based rod system. Neutrally adapted photopic spectral sensitivities are broad and roughly equal to those of adults tested under similar conditions, although infants may show an elevated sensitivity in the short-wavelength region of the spectrum. Spectral sensitivity has been shown to change with changes in chromatic adaptation. Some wavelength discriminations are possible under conditions in which brightness artifacts can be ruled out. All of these factors support the conclusion that young infants are at least dichromats. However, 2-month-olds to date have shown some unpredicted failures of chromatic discrimination (for example, yellow-greens from white), and the percentage of infants who demonstrate discriminations (for example, among wavelengths greater than or equal to 550 nm) improves with age in early infancy. Thus the status of young infants as trichromats is not yet clearly established. Stereopsis develops rapidly during months 3 to 7, and stereoacuities as good as 1' have been reported by 5 months postnatal. In summary, a variety of visual capabilities can now be measured in infants. Infants' visual capacities are rather surprisingly well established shortly after birth and undergo clear improvements during the first few postnatal months. The interpretation of developmental data and their bearing on visual theory are discussed.

Rayleigh discriminations in young human infants

The capacity of young infants to discriminate 3 × 3° broadband red or 550 nm green squares from a 589 nm yellow surround was tested by means of the forced-choice preferential looking technique. All 3-month olds, about 34 of the 2-month olds, and just under half of the one-month-olds could make at least one of these discriminations. Taken together with other known properties of infant color vision, the failures of discrimination shown by the younger infants are more readily modeled as immaturities of neural processing than as an absence or anomaly of LWS or MWS cones.

“Human Infant Color Vision and Color Perception” reviewed and reassessed: A critique of Werner and Wooten (1979a)

Wemer and Wooten (1979a) review the literature in infant color vision with aims to (1) criticize early studies of infant color perception, (2) review modem studies on spectral sensitivity and tests of chromatic discrimination, (3) assess the idea that infants and adults perceive hue categorically, and (4) evaluate contemporary knowledge about the development of color vision in infancy. The purposes of this paper are to (I) provide a comprehensive assessment of Werner and Wooten's review, (2) re-evaluate major conclusions of their review, and (3) rectify unwarranted criticism that their review levels against several experiments, particularly my own.

Infant color vision: A search for short-wavelength-sensitive mechanisms by means of chromatic adaptation

Incremental thresholds for short- and middle-wavelength test spots, projected upon blue and yellow backgrounds, were determined for 2 mth old infants. Three out of four infants tested showed a change in relative sensitivity to 460 and 560 nm test spots with a change in the wavelength composition of the backgrounds, indicating the existence of at least two separately adaptable chromatic mechanisms. When infant spectral sensitivity under yellow adaptation was examined in more detail, however, it did not agree with that of adults tested under comparable conditions. In adults, the yellow background revealed a short-wavelength mechanism ( λ max = 440 nm ) in isolation, but did not do so in most 2 and 3 mth old infants. The infants who were least sensitive to short wavelengths on an absolute scale also deviated most from adult-like spectral sensitivity. We tentatively interpret this difference between adults and infants as an immaturity of the infant's short-wavelength-sensitive mechanism.

White-adapted photopic spectral sensitivity in human infants

Two human infants, 2–3 months of age, were tested by a forced-choice preferential looking technique, for the detection of chromatic and white stimuli superimposed on a white adapting field. Three adults were also tested by the method of adjustment in the same apparatus. Both adult and infant curves were relatively flat, as expected under white-adapted conditions. The adults were about 1 Lu. more sensitive than the infants in absolute terms, but the relative spectral sensitivity curves were similar. The results help to justify the use of adult spectral sensitivity curves as a first approximation to infant values, but do not eliminate the need for careful brightness controls in studies of infant color vision.

Responses of Neonates to Colored Stimuli

More recent investigations of infant color vision (Fagan 1974; Spears 1964) have used Munsell color papers which allow hue, saturation, and brightness levels to be specified. The major drawback of the Munsell colors for use in infant research is that the brightness controls are based on adult spectral sensitivity and there is evidence (Dobson 1976; Teller & Peeples, Note 1) that the spectral sensitivity of infants is different from that of adults. Specifically, Dobson (1976) has found that, compared with adults, infants show elevated sensitivity to stimuli in the short-wavelength end of the spectrum, but show similar sensitivity for long-wavelength stimuli. Thus, infant color research that includes Munsell colors from both

Color vision and hue categorization in young human infants.

Two studies examined the organization of color perception in 4-month-old human infants. In Study 1, infants looked at selected spectral stimuli repeatedly until their visual attention waned. The stimuli represented instances of basic adult hue categories - blue, green, yellow, and red. Following habituation, infants were shown a series of wavelengths which were the same as or different from the stimuli first seen. Analyses of infant attention during this dishabituation phase of the study indicated that infants categorize wavelengths by perceptual similarity; that is, they see hues in the spectrum much as adults do. In Study 2, a group of infants who looked at the alteration of two wavelengths from the same hue category habituated as did the group of infants who looked at the repitition of a single wavelength from that category, but a group of infants who looked at two wavelengths from different categories habituated at a slower rate. Data from the two studies suggest a high degree of organization of the color world prior to language acquisition.

Color vision and hue categorization in young human infants.

Color vision and hue categorization in young human infants.

Development of color vision in newborn infants

Development of color vision in newborn infants

Color vision in infants.

Color vision in infants.