A conflict-based model of color categorical perception: evidence from a priming study

Categorical perception (CP) of color manifests as faster or more accurate discrimination of two shades of color that straddle a category boundary (e.g., one blue and one green) than of two shades from within the same category (e.g., two different shades of green), even when the differences between the pairs of colors are equated according to some objective metric. The results of two experiments provide new evidence for a conflict-based account of this effect, in which CP is caused by competition between visual and verbal/categorical codes on within-category trials. According to this view, conflict arises because the verbal code indicates that the two colors are the same, whereas the visual code indicates that they are different. In Experiment 1, two shades from the same color category were discriminated significantly faster when the previous trial also comprised a pair of within-category colors than when the previous trial comprised a pair from two different color categories. Under the former circumstances, the CP effect disappeared. According to the conflict-based model, response conflict between visual and categorical codes during discrimination of within-category pairs produced an adjustment of cognitive control that reduced the weight given to the categorical code relative to the visual code on the subsequent trial. Consequently, responses on within-category trials were facilitated, and CP effects were reduced. The effectiveness of this conflict-based account was evaluated in comparison with an alternative view that CP reflects temporary warping of perceptual space at the boundaries between color categories.     

Typicality, graded membership, and vagueness

This paper addresses theoretical problems arising from the vagueness of language terms, and intuitions of the vagueness of the concepts to which they refer. It is argued that the central intuitions of prototype theory are sufficient to account for both typicality phenomena and psychological intuitions about degrees of membership in vaguely defined classes. The first section explains the importance of the relation between degrees of membership and typicality (or goodness of example) in conceptual categorization. The second and third section address arguments advanced by Osherson and Smith (1997), and Kamp and Partee (1995), that the two notions of degree of membership and typicality must relate to fundamentally different aspects of conceptual representations. A version of prototype theory-the Threshold Model-is proposed to counter these arguments and three possible solutions to the problems of logical selfcontradiction and tautology for vague categorizations are outlined. In the final section graded membership is related to the social construction of conceptual boundaries maintained through language use.     

Is the Lateralized Categorical Perception of Color a Situational Effect of Language on Color Perception?

This study investigated whether and how a person's varied series of lexical categories corresponding to different discriminatory characteristics of the same colors affect his or her perception of colors. In three experiments, Chinese participants were primed to categorize four graduated colors—specifically dark green, light green, light blue, and dark blue—into green and blue; light color and dark color; and dark green, light green, light blue, and dark blue. The participants were then required to complete a visual search task. Reaction times in the visual search task indicated that different lateralized categorical perceptions (CPs) of color corresponded to the various priming situations. These results suggest that all of the lexical categories corresponding to different discriminatory characteristics of the same colors can influence people's perceptions of colors and that color perceptions can be influenced differently by distinct types of lexical categories depending on the context.     

Color preferences according to gender and sexual orientation

The present study was undertaken to verify findings surrounding sex differences in color preferences, and to extend this realm of inquiry by looking for possible differences in color preferences associated with sexual orientation. Based on a large sample of North American college students, significant gender differences were found, with the main difference being a greater preference for shades of blue by males than by females. Females, on the other hand, tended to be more evenly divided than males between preferring both green and blue. Regarding sexual orientation, we found no significant differences between heterosexuals and homosexual/bisexuals of either gender. In other words, male and female homosexuals/bisexuals exhibited essentially the same configuration of color preferences as did their heterosexual counterparts.     

The impact of uniform color on judging tackles in association football

ObjectivesThe aim of the study was to question whether uniform color had any impact on judging tackles in football.DesignFifty-two videos showing the tackles of an achromatic and a chromatic team were individually presented in random order. The chromatic team's uniform color was changed to blue, green, red and yellow.MethodsFootball referees and participants with a high and minor level of understanding of the rules of football judged the roughness of each tackle.ResultsBy analyzing all four colors, results did not reveal any impact of uniform color. Restricting analysis to blue and red showed that referees and participants with a high level of understanding of the rules judged tackles from behind more harshly for players wearing red.ConclusionsThe study found some empirical support for associating red with aggression and emphasized a differential impact of blue versus red uniforms for tackles committed from behind.     

Color measurement and color theory: II. Opponent-colors theory

Quantitative opponent-colors theory is based on cancellation of redness by admixture of a standard green, of greenness by admixture of a standard red, of yellowness by blue, and of blueness by yellow. The fundamental data are therefore the equilibrium colors: the set A₁ of lights that are in red/green equilibrium and the set A₂ of lights that are in yellow/blue equilibrium. The result that a cancellation function is linearly related to the color-matching functions can be proved from more basic axioms, particularly, the closure of the set of equilibrium colors under linear operations. Measurement analysis treats this as a representation theorem, in which the closure properties are axioms and in which the colorimetric homomorphism has the cancellation functions as two of its coordinates.Consideration of equivalence relations based on opponent cancellation leads to a further step: analysis of equivalence relations based on direct matching of hue attributes. For additive whiteness matching, this yields a simple extension of the representation theorem, in which the third coordinate is luminance. For other attributes, precise representation theorems must await a better qualitative characterization of various nonlinear phenomena, especially the veiling of one hue attribute by another and the various hue shifts.     

Sex-Dimorphic Color Preference in Children with Gender Identity Disorder: A Comparison to Clinical and Community Controls

The present study was designed to assess sex-dimorphic color preferences in children with gender identity disorder (47 boys, 18 girls), clinical controls (65 boys, 35 girls), and community controls (65 boys, 35 girls). The mean age of the children was 7.63 years (range?=?3–12 years). Children were shown a hexagon-shaped display of 144 colors extracted from PowerPoint?. Each child was asked to choose his or her three favorite colors (Trials 1–3) by pointing to them, naming them, and then to provide a justification for each choice. From the entire array, children labeled a total of 11 different colors: black, blue, brown, gray, green, orange, pink, purple, red, white, and yellow. For three of the colors (blue, pink/purple, and red), there was evidence for normative sex differences in color preference, and, for the colors blue and pink/purple, the gender-referred children showed inverted patterns of color preference. For the color blue, luminance values showed that the gender-referred boys and control girls preferred lighter shades, whereas the gender-referred girls and control boys preferred darker shades. Qualitative analysis indicated that gender-specific justifications were uncommon, even for the sex-dimorphic colors. Gender-referred children showed inverted gender-stereotyped color preferences, which are likely related to their more general pattern of cross-gender identification. Principles of gender-differentiated development derived from gender-schema theory are used to explain the group differences in color preferences.     

How Red,Blue, and Green are Affectively Judged

The present study aimed at examining how the colors red, blue, and green were affectively judged through three variables: dominance, arousal, and pleasure. All participants were exposed to red, blue, green, and white (control condition), which were created using the hue–saturation–value color model. Then, participants were invited to rate their perceptions using the self‐assessment manikin. Results showed that (a) red was strongly associated with dominance and arousal; (b) blue was moderately and slightly associated with dominance and arousal, respectively; (c) green was slightly associated with arousal; and (d) blue and green were slightly more pleasurable than red. These results provide initial insights into how people perceive colors through the notions of dominance, arousal, and pleasure. Important practical implications for the use of colors are discussed. Copyright © 2016 John Wiley & Sons, Ltd.     

Domain differences in the structure of artifactual and natural categories

In three experiments, different methodologies, measures, and items were employed to address the question of whether, and to what extent, membership in a semantic category is all or none (i.e., absolute) or a matter of degree (i.e., graded). Resemblance theory claims that categorization is based on similarity, and because similarity is graded, category membership may also be graded. Psychological essentialism asserts that categorization is based on the presumption of the category essence. Because artifactual (e.g., FURNITURE) and natural (e.g., FRUIT) categories have different sorts of essences, artifacts and natural kinds may be categorized in qualitatively different manners. The results converged onthe finding of a robust domain difference in category structure: Artifactual categories were more graded than natural categories. Furthermore, typicality reliably predicted absolute category membership, but failed to predict graded category membership. These results suggest that resemblance theory and psychological essentialism may provide a concerted account of representation and categorization across domains.     

Testing the Cross-Cultural Generality of Hering's Theory of Color Appearance

This study examines the cross-cultural generality of Hering's (1878/1964) color-opponent theory of color appearance. English-speaking and Somali-speaking observers performed variants of two paradigms classically used to study color-opponency. First, both groups identified similar red, green, blue, and yellow unique hues. Second, 25 English-speaking and 34 Somali-speaking observers decomposed the colors present in 135 Munsell color samples into their component Hering elemental sensations—red,green,blue, yellow, white, and black—or else responded “no term.” Both groups responded no term for many samples, notably purples. Somali terms for yellow were often used to name colors all around the color circle, including colors that are bluish according to Hering's theory. Four Somali Grue speakers named both green and blue elicitation samples by their term for green. However, that term did not name the union of all samples called blue or green by English speakers. A similar pattern was found among three Somali Achromatic speakers, who called the blue elicitation sample black or white. Thus, color decomposition by these Somali-speaking observers suggests a lexically influenced re-dimensionalization of color appearance space, rather than a simple reduction of the one proposed by Hering. Even some Somali Green-Blue speakers, whose data were otherwise similar to English, showed similar trends in yellow and blue usage. World Color Survey data mirror these results. These within- and cross-cultural violations of Hering's theory do not challenge the long-standing view that universal sensory processes mediate color appearance. However, they do demonstrate an important contribution of language in the human understanding of color.     

EFFECTS OF D‐AMPHETAMINE IN A TEMPORAL DISCRIMINATION PROCEDURE: SELECTIVE CHANGES IN TIMING OR RATE DEPENDENCY?

Two experiments evaluated rate dependency and a neuropharmacological model of timing as explanations of the effects of amphetamine on behavior under discriminative control by time. Four pigeons pecked keys during 60-trial sessions. On each trial, the houselight was lit for a particular duration (5 to 30 s), and then the key was lit for 30 s. In Experiment 1, the key could be lit either green or blue. If the key was lit green and the sample was 30 s, or if the key was lit blue and the sample was 5 s, pecks produced food on a variable-interval 20-s schedule. The rate of key pecking increased as a function of sample duration when the key was green and decreased as a function of sample duration when the key was blue. Acute d-amphetamine (0.1 to 3.0 mg/kg) decreased higher rates of key pecking and increased lower rates of key pecking as predicted by rate dependency, but did not shift the timing functions leftward (toward overestimation) as predicted by the neuropharmacological model. These results were replicated in Experiment 2, in which the key was lit only one color during sessions, indicating that the effects were not likely due to disruption of discriminative control by key color. These results are thus consistent with rate dependency but not with the predictions of the neuropharmacological model.     

Color and Similarity1

Similarity claims about the colors, for instance that blue is more similar to purple than to yellow, are Sometimes held to pose a serious problem for physicalism about color: the view that colors are physical properties of some kind. I examine various responses to this problem, find them wanting, and give my own solution, which appeals to the way colors are visually represented. Finally, I argue that the proposed account removes the principal motivation for Lewis's and Walker's response to Kripke's Wittgenstein, in terms of “natural” properties.     

Modelling courage: The role of dissent in fostering independence

While dissent has been construed in terms of social support and informational influence, this paper hypothesizes that exposure to dissenting minority views, even when they are wrong, stimulates resistance to conformity and increased adherence to one's own views. In this study, individuals in groups of four judged the colour of a series of blue stimuli and were exposed to one individual who consistently judged the stimuli to be ‘green: inconsistently judged them to be 'green' or expressed no dissent. In a subsequent setting, when judging a series of red slides; subjects were exposed to a majority who repeatedly judged them as 'orange’. Exposure to dissent, whether it was consistent or inconsistent, substantially reduced the level of conformity. In fact, exposure to the consistent dissent led to almost complete independence.     

Context-dependent variation in social stereotyping 2: The relationship between frame of reference,self-categorization and accentuation

This paper examines the hypothesis that patterns of stereotypic accentuation reflect the degree to which judged stimuli share the same social category membership as the stereotyper, Following self-categorization theory, the degree of this shared identity is operationalized in terms of the meta-contrast ratio as a function of the positions of (a) stereotyper and (b) stereotyped target relative to (c) the stereotyper's frame of reference. Three experiments are reported which sought to manipulate shared category membership either by extension of subjects' frame of reference or by extremitization of target and subject with respect to that frame. As predicted, greater shared identity was associated with stronger assimilation of the target to subjects' own position and with change in stereotype content. Findings are discussed in relation to theories of personality, social judgement and social cognition. Like the accentuation processes which underpin them, it is proposed that stereotypes are sensitive to comparative context and that they reflect veridically the social self-categorical properties of stimuli.     

What Is Graded Membership?

It has seemed natural to model phenomena related to vagueness in terms of graded membership. However, so far no satisfactory answer has been given to the question of what graded membership is nor has any attempt been made to describe in detail a procedure for determining degrees of membership. We seek to remedy these lacunae by building on recent work on typicality and graded membership in cognitive science and combining some of the results obtained there with a version of the conceptual spaces framework.     

Visual aftereffect of texture density contingent on color of frame

An aftereffect of perceived texture density contingent on the color of a surrounding region is reported. In a series of experiments, participants were adapted, with fixation, to stimuli in which the relative density of two achromatic texture regions was perfectly correlated with the color presented in a surrounding region. Following adaptation, the perceived relative density of the two regions was contingent on the color of the surrounding region or of the texture elements themselves. For example, if high density on the left was correlated with a blue surround during adaptation (and high density on the right with a yellow surround), then in order for the left and right textures to appear equal in the assessment phase, denser texture was required on the left in the presence of a blue surround (and denser texture on the right in the context of a yellow surround). Contingent aftereffects were found (1) with black-and-white scatter-dot textures, (2) with luminance-balanced textures, and (3) when the texture elements, rather than the surrounds, were colored during assessment. Effect size was decreased when the elements themselves were colored, but also when spatial subportions of the surround were used for the presentation of color. The effect may be mediated by retinal color spreading (Pöppel, 1986) and appears consistent with a local associative account of contingent aftereffects, such as Barlow’s (1990) model of modifiable inhibition.     

A rule-based categorization deficit in Alzheimer's disease?

This study examined the categorization processes that Alzheimer's disease (AD) patients use during assessments of semantic memory. Rule-based categorization involves the careful, analytic processing of strict criteria to determine category membership, particularly for items from graded categories with ambiguous category membership; similarity-based categorization requires an overall comparison of a test stimulus with a prototype or remembered exemplar of the category and is relatively effective for the rapid categorization of items with unambiguous category membership. To assess these processes in AD, patients were asked to decide the category membership of test stimuli for categories with poorly defined or fuzzy boundaries (e.g., VEGETABLE) and for categories with well-defined boundaries (e.g., FEMALE) and then to judge the representativeness of the test stimulus for its chosen category. A subgroup of AD patients demonstrated a typical pattern of impaired semantic memory compared to healthy control subjects; that is, difficulty deciding the category membership of test items from fuzzy categories. Among these patients, we found no deficit in category membership decisions about items taken from well-defined categories. We also found that AD patients and healthy controls do not differ in their representativeness judgments of items within a correctly judged category. These findings are most consistent with the hypothesis that rule-based categorization difficulty limits semantic memory in AD.     

Identification and adaptation of hue: Parallels in the operation of mechanisms that underlie categorical perception in vision and in audition

Summary Four experiments were conducted to examine processes in identification and selective adaptation of hues in color perception that exactly parallel processes in identification and adaptation of auditory detectors that provide information for phonemic perception. The first experiment demonstrated an effect of adaptation on identification of blue and green when a hue category center was used as the adaptor; this experiment also assessed recovery from adaptation. Adaptation to one hue was found to shift identification to favor the alternative hue, implicating a single detector underlying hue categorization. The second experiment demonstrated similar effects of adaptation between green and yellow. The third experiment compared the magnitudes of shift following adaptation with a category center, a near-boundary hue, and variously graded adaptation series. Adaptation was found to be related to the category representativeness of the adaptor(s). Results of the third experiment also provided support for the view that adaptation, rather than response bias, is responsible for shifts in the position of identification functions following extended stimulus exposure. The fourth experiment explored the neural loci of adaptation by an interocular transfer test. Hue adaptation was found to occur at both central and peripheral loci. In the four main experiments, reaction times to identify hues in unadapted and adapted states were also analyzed and compared. Subsidiary experiments assessed the effects of stimulus luminance on the magnitude of adaptation. General principles of categorical perception and its underlying bases, including the sweep, magnitude, and symmetry of adaptation, are discussed. The principal findings of these studies provide new data on hue perception which strikingly parallel findings in speech perception.     

A ratio principle for a red/green and a yellow/blue channel?

There is strong empirical evidence that, under adaptation to another achromatic color stimulus, the lightness of an achromatic color stimulus depends on the ratio of the luminances of the two stimuli. In the present study, the suitability of this ratio principle is tested for two chromatic postreceptoral opponent channels. A Hering red/green channel and a non-Hering yellow/blue channel are specified as chromatic channels. The yellow/blue channel is defined by extrapolating the plane corresponding to unique green-white linearly to the reddish part of color space, using the plane’s surface as the channel’s equilibria. The experiment was run on an isoluminant plane, measured individually for each observer. Moving along an observer’s measured opponent axes, eight adaptation stimuli were selected for each channel and spanned the whole range of the channel’s coordinates. Red/green equilibria or yellow/blue equilibria were measured as excursions along the adaptation axes. For both presumed channels, the ratios of the equilibrium coordinates of test and adaptation stimuli were essentially constant. This supports the principle’s suitability. However, small asymmetries were found with respect to each channel’s opponent hues. The status of the proposed yellow/blue channel is discussed, as are conditions that might have favored the present findings.     

Color blend retrievals: Compromise memories or deliberate compromise responses?

A total of 978 subjects, in two experiments and two pilot studies, were asked to recognize the color of objects to which they had been exposed in a slide presentation. Taken together, the studies demonstrate that an object’s typical coloration influences recognitions, resulting in retrievals that compromise or blend the actual color and the typical color. In addition, Experiment 2 suggests that color recognitions may be simultaneously influenced by typical knowledge, event information, and postevent information. The findings question the adequacy of both the deliberate compromise and the compromise memory hypotheses as accounts for color blend retrievals. The deliberate compromise hypothesis fails to account for evidence that blend retrievals result because an intact representation of an event is not available at the time of test. The compromise memory hypothesis fails to account for evidence that deliberative processes do occur, and is in need of further exposition given that blend retrievals may be the result of different processes when resulting from typical knowledge and from postevent information. In conclusion, neither hypothesis, in isolation, is able to account for the various possible processes that appear responsible for blend retrievals.