Lightness constancy in 4-month-old infants

Developmental changes in colour constancy in a naturalistic object selection task

When the illumination falling on a surface change, so does the reflected light. Despite this, adult observers are good at perceiving surfaces as relatively unchanging-an ability termed colour constancy. Very few studies have investigated colour constancy in infants, and even fewer in children. Here we asked whether there is a difference in colour constancy between children and adults; what the developmental trajectory is between six and 11 years; and whether the pattern of constancy across illuminations and reflectances differs between adults and children. To this end, we developed a novel, child-friendly computer-based object selection task. In this, observers saw a dragon's favourite sweet under a neutral illumination and picked the matching sweet from an array of eight seen under a different illumination (blue, yellow, red, or green). This set contained a reflectance match (colour constant; perfect performance) and a tristimulus match (colour inconstant). We ran two experiments, with two-dimensional scenes in one and three-dimensional renderings in the other. Twenty-six adults and 33 children took part in the first experiment; 26 adults and 40 children took part in the second. Children performed better than adults on this task, and their performance decreased with age in both experiments. We found differences across illuminations and sweets, but a similar pattern across both age groups. This unexpected finding might reflect a real decrease in colour constancy from childhood to adulthood, explained by developmental changes in the perceptual and cognitive mechanisms underpinning colour constancy, or differences in task strategies between children and adults. HIGHLIGHTS: Six- to 11-year-old children demonstrated better performance than adults on a colour constancy object selection task. Performance decreased with age over childhood. These findings may indicate development of cognitive strategies used to overcome automatic colour constancy mechanisms.

The Development of Color Perception and Cognition

Color is a pervasive feature of our psychological experience, having a role in many aspects of human mind and behavior such as basic vision, scene perception, object recognition, aesthetics, and communication. Understanding how humans encode, perceive, talk about, and use color has been a major interdisciplinary effort. Here, we present the current state of knowledge on how color perception and cognition develop. We cover the development of various aspects of the psychological experience of color, ranging from low-level color vision to perceptual mechanisms such as color constancy to phenomena such as color naming and color preference. We also identify neurodiversity in the development of color perception and cognition and implications for clinical and educational contexts. We discuss the theoretical implications of the research for understanding mature color perception and cognition, for identifying the principles of perceptual and cognitive development, and for fostering a broader debate in the psychological sciences.

Infants' anticipatory eye movements: feature-based attention guides infants' visual attention

When looking for an object, we identify it by selectively focusing our attention to a specific feature, known as feature-based attention. This basic attentional system has been reported in young children; however, little is known of whether infants could use feature-based attention. We have introduced a newly developed anticipation-looking task, where infants learned to direct their attention endogenously to a specific feature based on the learned feature (color or orientation), in 60 preverbal infants aged 7-8 months. We found that preverbal infants aged 7-8 months can direct their attention endogenously to the specific target feature among irrelevant features, thus showing the feature-based attentional selection. Experiment 2 bolstered this finding by demonstrating that infants directed their attention depending on the familiarized feature that belongs to a never-experienced object. These results that infants can form anticipation by color and orientation reflect they could drive their attention through feature-based selection.

Colour category constancy and the development of colour naming

In this study, we investigated the processes of coordination, adaptation, and calibration during the development of colour naming and colour constancy, and we tested whether colour term knowledge is related to colour constancy. We measured category membership and prototypes with 163 Munsell chips in preschool children (3- to 4-year-old) under neutral, green, and red illuminations, and compared their results to those of adults. We introduced an index of colour term maturity based on the similarity of children's colour term use to adults, and a colour category constancy index that quantifies the variation in colour categorisation that is specific to illumination changes. Results showed that illumination changes affected children's consistency of colour categorisation, but only to a small extent. However, colour term maturity and illumination-specific effects on consistency strongly varied in this age range. Correlations between colour term maturity and illumination-specific consistency indicated that colour constancy increases with colour term acquisition; but those results depended on the type of illumination changes (between neutral, green, and red). Together, our findings suggest that children progressively fine-tune and recalibrate the meaning of colour terms through processes of coordination and adaptation that are also involved in the calibration of colour constancy.

Infants' perception of lightness changes related to cast shadows

When humans perceive the lightness of an object’s surface in shadows there is an implicit assumption that cast shadows dim the surface. In two experiments, we investigated whether 5- to 8-month-old infants make this assumption about shadows. According to this shadow assumption, the apparent change in lightness produced by shadows on an object’s surface are attributed to blocked light sources. If infants can use the shadow assumption to perceive the object’s lightness in shadows, they will also be able to detect unnatural lightness changes in shadows. We compared the infants’ looking times to the unnatural and the natural lightness changes in the shadow when an object (duck) goes through the cast shadow. In Experiment 1, we examined whether infants could detect the unnatural lightness changes of the object’s surface in shadows. We created computer-graphic movies of unnatural and natural lightness changes to the duck’s surface. Our results showed that 7- to 8-month-olds but not 5- to 6-month-olds significantly preferred the movie with the unnatural changes in lightness, indicating that only the older infants could detect these changes. In Experiment 2, we confirmed that the infants’ preference was based on the detection of unnatural lightness changes according to the shadow assumption. The natural and the unnatural lightness changes of Experiment 1 were presented without cast shadows. Under these conditions, neither younger nor older infants showed a significant preference. Taken together, the experiments showed that 7- to 8-month-old infants could detect the unnaturalness of a surface’s lightness changes produced by shadows. In conclusion, our findings suggest that 7- to 8-month-old infants can perceive an object’s lightness in shadows by using an assumption that cast shadows dim the surface of an object.

Can Infants Tell the Difference between Gold and Yellow?

There is a large literature focused on the color perception of matte surface. However, recent research showed that the component of surface specular reflection, such as glossiness, also affects categorical color perception. For instance, the color term "gold" was used to name high specular stimuli within a specific range of chromaticity, which overlaps with those of yellow and orange for low specular stimuli. In the present study, we investigated whether the component of surface specular reflectance affects the color perception of 5- to 8-month-old infants by using the preferential looking technique. In the first experiment, we conducted a simple test to determine whether infants perceive yellow and gold as the same color by comparing their preference for these colors over green. If the infants perceive yellow and gold as the same color, they would show similar preference scores over green. On the other hand, if infants show different preference scores over green, it indicates that infants do not perceive yellow and gold as the same color. Only the 7-8 month-old infants showed different preference scores for gold and yellow over green. This result indicates that the 7-8 month-old infants perceive gold and yellow as different colors. In Experiment 2, we eliminated the component of specular reflectance on the gold surface and presented it against green to infants. A similar preference score of yellow over green was obtained. This result suggests that the difference between the preference scores for gold and yellow over green in Experiment 1 was based on representations of glossiness.

The comparator model of infant visual habituation and dishabituation: recent insights

Current knowledge of the perceptual and cognitive abilities in infancy is largely based on the visual habituation-dishabituation method. According to the comparator model [e.g., Sokolov (1963a) Perception and the conditioned reflex. Oxford: Pergamon Press], habituation refers to stimulus encoding and dishabituation refers to discriminatory memory performance. The review also describes the dual-process theory and the attention disengagement approach. The dual-process theory points to the impact of natural stimulus preferences on habituation-dishabituation processes. The attention disengagement approach emphasizes the contribution of the ability to shift the attention away from a stimulus. Moreover, arguments for the cognitive interpretation of visual habituation and dishabituations are discussed. These arguments are provided by physiological studies and by research on interindividual differences. Overall, the review shows that current research supports the comparator model. It emphasizes that the investigation of habituation and dishabituation expands our understanding of visual attention processes in infants.

Infants' responsiveness to lightness changes on a dynamic three-dimensional surface

In a looking-time study, 24 infants 6 months of age were presented with continuously folding and unfolding patterns of stripes. The luminances in the dynamic lightness constancy pattern were changed in such way that adults attribute them to changes of the various regions' orientation relative to the light source (lightness constancy display). The "reversed" lightness constancy stimulus consisted of a continuously folding and unfolding pattern, in which the luminance changes were not consistent with a striped surface illuminated from one side. The only difference between the animations was the relationship between the change in surface orientation and the change of luminances. The infants looked significantly longer at the reversed lightness constancy animation than at the lightness constancy display. This finding suggests that the infants detected the violation of the lightness constancy rules in the reversed lightness constancy stimulus. The infants were also presented with control animations to rule out the possibility that looking preferences were based on low-level properties of the display.

Die Entwicklung der räumlichen Wahrnehmung im Säuglingsalter: Eine Positionsbestimmung

Zusammenfassung. In den vergangenen Jahrzehnten ist eine Vielzahl experimenteller Studien mit dem Ziel durchgeführt worden, den Zeitpunkt der Entstehung der räumlichen Wahrnehmung im ersten Lebensjahr aufzuspüren. Ein Problem dieser Forschungsarbeiten besteht darin, dass sie auf keine einheitlichen Altersangaben hin konvergieren und so keine sicheren Schlussfolgerungen darüber zulassen, ab wann genau die jeweilige Wahrnehmungsleistung vorhanden ist. Insbesondere im Bereich der bildhaften Tiefenwahrnehmung gibt es eine vermeintliche Diskrepanz in den Ergebnissen von Studien, in denen die Methode des präferentiellen Greifens zur Anwendung kommt, und Studien, in denen das kindliche Blickverhalten beobachtet wird. Aufgabe der Forschung ist daher die Entwicklung und Anwendung von Heuristiken, mit deren Hilfe eine Klärung der Faktoren erfolgen kann, die für derartige unterschiedliche Befundlagen verantwortlich sind. Zu diesen Heuristiken zählen das Verfahren der metaanalytischen Auswertung vorhandener Ergebnisse sowie die Anwendung unterschiedlicher Untersuchungsmethoden und Versuchsdesigns auf einen Inhaltsbereich. Am Beispiel der bildhaften Tiefenwahrnehmung wird dargestellt, dass eine metaanalytische Vorgehensweise die Theorienbildung vorantreiben kann. Zudem werden unterschiedliche experimentelle Designs und Techniken der Datenerhebung skizziert und in ihrer Rolle für die Forschung erläutert.

Perception of Surface Glossiness by Infants Aged 5 to 8 Months

We examined glossiness perception in infants using a preferential looking paradigm. In experiment 1, the images of two doll-shaped objects with matte and glossy surfaces were presented to infants aged 5 to 6 and 7 to 8 months. The results showed that the 7 to 8 month olds, but not the 5 to 6 month olds, looked significantly longer at the glossy object than at the matte object. In experiment 2, we additionally employed an object that was matte and covered with textures of white paint splashes, whose luminance histogram was almost identical to that of the glossy object. The results showed that the 7 to 8 month old infants could discriminate between the glossy object and the textured object even though both had similar luminance histograms. Qualitatively similar results were obtained for simple spheres that did not contain facial features. Therefore, the results of experiments 1 and 2 were not due to differences in the visibility of the dolls' facial features. These findings suggest that 7 to 8 month old infants perceive difference between glossy objects and matte objects on the basis of surface representations.

Covariation of color and luminance facilitate object individuation in infancy

The ability to individuate objects is one of our most fundamental cognitive capacities. Recent research has revealed that when objects vary in color or luminance alone, infants fail to individuate those objects until 11.5 months. However, color and luminance frequently covary in the natural environment, thus providing a more salient and reliable indicator of distinct objects. For this reason, we propose that infants may be more likely to individuate when objects vary in both color and luminance. Using the narrow-screen task of Wilcox and Baillargeon (1998a), in Experiment 1 we assessed 7.5-month-old infants' ability to individuate uniformly colored objects that varied in both color and luminance or luminance alone. Experiment 2 further explored the link between color and luminance by assessing infants' ability to use pattern differences that included luminance or color to individuate objects. Results indicated that infants individuated objects only when covariations in color and luminance were used. These studies add to a growing body of literature investigating the interaction of color and luminance in object processing in infants and have implications for developmental changes in the nature and content of infants' object representations.

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.