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This chapter is divided into six sections. The first sets out the background of the debate about the relationship between language and cognition in the color domain. The second explains how recent studies of color recognition employing visual search tasks have clarified this relationship. This section also argues that these studies point to the existence of two separate systems that influence perception and categorization of color; one of which is linguistically based, and one of which is not affected by language. The third section critically evaluates recent claims that there are similarities between color terms in the world's languages that point to the existence of color universals. The fourth section examines children's color term acquisition in an attempt to trace the mechanisms by which color categories are acquired. It also discusses whether infants have an innate prepartitioned organization of color categories that is overridden during the learning process. The two final sections outline some outstanding questions, note some methodological constraints on the conclusions that can be drawn from the accumulated evidence, and argue that much more empirical investigation is still needed in this field.

The third period of lightness theory saw the arrival of the Gestalt psychologists, with their penetrating insights and dramatic experiments. Rejecting the clumsy two-stage conception of raw sensations and cognitive interpretation, they proposed a single perceptual process that was parsimonious and elegant. The emergence of Gestalt theory is often tied to the 1912 publication of Max Wertheimer's paper on apparent motion. But the Gestaltists did not really turn their attention to lightness until the early 1930s. When they did, they turned the field upside down. In the short space of five years they published a series of devastating crucial experiments. David Katz, who represented the standard view of lightness, was in retreat on every issue on which Gestalt theory challenged him. The Gestalt period was cut short by the tragic events surrounding World War II.

Color perception requires a distinction between both chromatic colors and achromatic colors. These are funny terms: the first is redundant, the second is an oxymoron — colored colors and non-colored colors. This introduction looks at the perception of achromatic colors, sometimes called neutral colors or nonselective colors. By extension, the discussion includes the achromatic dimension of chromatic colors. For example, pink differs from maroon only on this dimension. The emphasis is on the perception of surface color, which is the property of an object, rather than on the perception of light. The perception of objective properties of the real, everyday world, not isolated patches of light in a dark laboratory, is explored.

This chapter adopts a psychophysical approach to studying color vision and reviews the evolution of color perception in vertebrates. Color vision in goldfish is described as an example before data from other vertebrate species are given for comparison. Comparing the color vision systems in different vertebrate taxa based on behavioral data indicates that a highly developed trichromatic or tetrachromatic color vision must be a very old invention of vertebrates, as it occurs in fishes, amphibia, reptiles, and birds. In mammals, this type of color vision is widely absent and had obviously been reinvented by Old World primates.

This chapter demonstrates that human surface colour perception can be modelled as algorithms that, over certain ranges of environmental conditions, manage to assign colours to objects that are in correspondence with specific, objective properties of the object's surface, called intrinsic colours. The chapter suggests that under certain circumstances, human observers do seem to estimate intrinsic surface colours accurately. Environmental constraints permit us to succeed in perceiving stable surface colours. These constraints can be thought of as a list of precise assertions concerning a visual scene. If all of the assertions on the list are true of the scene, then human colour vision, confined to a specified environment, will assign colours to surfaces in that scene that are the same as those it assigns to these surfaces in another scene that also satisfies these assertions.

This chapter focuses on the possible functional differences between modal and amodal completion in relation to visual attention. A review of visual-search experiments suggests that both modal and amodal completion may arise preattentively, that is, at parallel stages of vision, and even when counter to the observer's intentions. However, the two forms of completion may then differ in their effect upon attention, with attention tending to spread between inducing fragments and completed regions only for the case of modal completion, for which filling-in arises in the completed region.

This chapter focuses on the notion of colour as a property of the surfaces of objects. It examines the arguments of objectivists who seek to reduce colour to a physical property of object surfaces. Subjectivists, by constrast, seek to argue that no such reduction is possible, and hence that colour must be wholly subjective. This chapter presents a relationalist position that best accommodates the primary data concerning colour perception, and permits a better understanding of the ways in which colour is both objective and subjective. It ends with a reconsideration of the notions of objectivity and subjectivity themselves, and a consideration of how modern technology can foster misleading expectations about the specificity of colour properties.

The degree of surface colour constancy that we experience depends on viewing conditions: under some circumstances, we have essentially none, and under others, we show a remarkable, nearly perfect, degree of constancy. This chapter considers an analogous explanation for failures and successes of surface colour perception, based on the illuminant estimation hypothesis. An evident implication of this illuminant estimation hypothesis is that the number and strength of illuminant cues present in a scene limit the degree of colour constancy possible: little colour constancy is possible in scenes devoid of illuminant cues. If a colour visual system fails to make use of the cues available, we would also expect errors in surface colour perception as a consequence.

In unpacking the main tenets of Buddhist epistemology, this chapter offers a detailed analysis of perception as an epistemic modality centred on three main points: (1) the cognitive function of perception as an epistemic warrant; (2) the ontological status of perceptual objects; and (3) the relation between perception and conception. A variety of arguments about word-meaning relations, and about the proper use of philosophical terminology are considered throughout. The chapter juxtaposes the views of Buddhists with those of their principal opponents, and explores different ways of casting this classical philosophical debate in terms of contemporary inquiries into such things as the nature and limits of perceptual knowledge. It also explores the tension between empirical knowledge and reportability, by differentiating between substantive philosophical disagreements and mere verbal disputes. The chapter concludes with an examination of the relation between cognitive errors and perceptual illusions, drawing from some recent empirical studies of perception.

This chapter summarizes the discussions in the preceding chapters. It argues that the sensorimotor approach, by taking feel as an abstract quality of our interaction with the environment, helps provide an explanation for consciousness in a biological or physical system. Far from being simply a philosophical stance, the sensorimotor approach makes empirically verifiable predictions and opens new research programs in topics such as visual attention, sensory substitution, color and tactile perception, and robotics.

Intense preoccupation with visual field defects has resulted hitherto mainly from interest in the anatomical relationships between retinal fields, fibre connections, and cortical areas. This led to a schematic geometrical treatment of these defects that did not adequately take into account the variety of the practical functions of the field of vision. Hemiachromatopsia, viz. the hemianopic loss of colour perception with the preservation of the visual field for white; hemiamblyopia, viz the increase of the intensity threshold in a particular portion of the visual field; and, finally, the reduction of attention in the otherwise perceptually normal hemifield — all these observations point to a much wider variety of visual field disorders than one would expect from a purely geometrical point of view. The perception of colours has no clear-cut border in itself, but is centripetally reduced rather than limited in a geometrical way. Thus, colour perception in the visual field follows the principle of a pathological increase in threshold level and not a geometrical line of demarcation.

This chapter explains memory color as an enhancement of perceptual learning, which enables us to better differentiate objects from their backgrounds. In cases of memory color, faded types of objects with which we associate a prototypical color are sometimes perceived as closer to that color than they actually are. For instance, discolored hearts sometimes appear redder to us than they actually are, and discolored bananas yellower. The goal of this chapter is to understand memory color in terms of perceptual learning. The chapter argues that memory color enhances perceptual learning by enabling us to better differentiate objects from their backgrounds. This account of cases of memory color parts ways with an influential philosophical interpretation of them: that they should be understood as cases of cognitive penetration. It also parts ways with the standard interpretation of memory color cases in psychology: that they should be understood as cases of color constancy.

This chapter examines categorical colour perception and the nature of central processing of colour in a 33-year-old male with X-linked incomplete achromatopsia. Data from colour naming and categorization, colour contrast adaptation, and a battery of standard colour tests performed with and without a rod bleach, are presented. It is shown that despite colour deficiencies, the subject demonstrates consisted but shifted colour category and naming behaviour, while showing weak evidence for selectively tuned central chromatic mechanisms.

This chapter surveys a few of the so-called “easy” problems, as referred to by Chalmers, in understanding color perception. The obscurity of psycho-neural isomorphism is highlighted by the difficulties encountered in the domain of color, and while this theme has been discussed extensively, the discussion here at least provides an opportunity to review interesting facts and ideas about color vision. Trichromacy is considered first in this chapter, since it provides the most familiar example of physiological explanation in perception—an explanation generally held to be straightforward, simple, and completely satisfactory. However, as is shown in the latter part of this chapter, the neural basis of trichromacy is not yet well understood. The prospects for physiological explanation of less elementary aspects of color vision are also discussed in broad terms, and the conclusions reached here are also discouraging for current theoretical perspectives.

This chapter examines the theoretical and empirical research into evolutionary aspects of four complex issues of human behaviour in sports. We highlight how evolutionary approaches have promoted our understanding of human sports and competition. To begin with, we describe the relationship between sports competitions and testosterone levels and elucidate how winning and losing leads to different, sometimes status-changing, endocrine responses. Secondly, we look at ‘home advantage’ and examine how hormonal and psychological research has aided our understanding of this well-known phenomenon. The next section focuses on possible evolutionary explanations as to why left-handers may have an advantage in physical combat in both traditional and westernized societies. The final section examines colour influences on human behaviour in general and on sports competition in particular, focusing specifically on the significance of the colour red in human competitive interactions. These four themes serve to highlight the value of evolutionary approaches in enhancing and enriching our understanding of human sports competitions.