It remains unclear what is being processed in blindsight in response to faces, colours, shapes, and patterns. This was investigated in two hemianopes with chromatic and achromatic stimuli with sharp or shallow luminance or chromatic contrast boundaries or temporal onsets. Performance was excellent only when stimuli had sharp spatial boundaries. When discrimination between isoluminant coloured Gaussians was good it declined to chance levels if stimulus onset was slow. The ability to discriminate between instantaneously presented colours in the hemianopic field depended (...) on their luminance, indicating that wavelength discrimination totally independent of other stimulus qualities is absent. When presented with narrow-band colours the hemianopes detected a stimulus maximally effective for S-cones but invisible to M- and L-cones, indicating that blindsight is mediated not just by the mid-brain, which receives no S-cone input, or that the rods contribute to blindsight. The results show that only simple stimulus features are processed in blindsight. (shrink)

Luminance and color are strong and self-sufficient cues to pictorial depth in visual scenes and images. The present study investigates the conditions Under which luminance or color either strengthens or overrides geometric depth cues. We investigated how luminance contrasts associated with color contrast interact with relative height in the visual field, partial occlusion, and interposition in determining the probability that a given figure is perceived as ‘‘nearer’’ than another. Latencies of ‘‘near’’ responses were analyzed to test for (...) effects of attentional selection. Figures in a pair were supported by luminance contrast or isoluminant color contrast and combined with one of the three geometric cues. The results of Experiment 1 show that luminance contrasts associated with hue, when it does not interact with other hues, produces the same effects as achromatic luminance contrasts: The probability of‘‘near’’ increases with luminance contrast while the latencies for ‘‘near’’ responses decrease. Partial occlusion is found to be a strong enough pictorial cue to support a weaker red luminance contrast. Interposition cues lose out against cues of spatial position and partial occlusion. The results of Experiment 2, with isoluminant displays of varying color contrast, reveal that red color contrast on a light background supported by any of the three geometric cues wins over green or white supported by any of the three geometric cues. On a dark background, red color contrast supported by the interposition cue loses out against green or white color contrast supported by partial occlusion. These findings reveal that color is not an independent depth cue, but is strongly influenced by luminance contrast and stimulus geometry. Systematically shorter response latencies for stronger ‘‘near’’ percepts demonstrate that selective visual attention reliably detects the most likely depth cue combination in a given configuration. (shrink)

What is colour vision for? In the popular imagination colour vision is for “seeing the colours” — adding hue to the achromatic world of shape, depth and motion. On this view colour vision plays little more than an ornamental role, lending glamour to an otherwise monochrome world. This idea has guided much theorising about colour within vision science and philosophy. However, we argue that a broader approach is needed. Recent research in the psychology of colour demonstrates that colour vision is (...) integral to a variety of visual processes, helping us to perform many types of visual tasks. We discuss some of this research and consider its implications for philosophical theories of colour. (shrink)

Summary The optical quality and properties of over 200 telescopes residing in museums and private collections have been measured and tested with the goal of obtaining new information about the early development of the achromatic lens (1757–1770). Quantitative measurements of the chromatic and spherical aberration of telescope objective lenses were made and are discussed within the context of John and Peter Dollond's description of their efforts to overcome these two optical defects inherent in any single lens. Their work was chronicled (...) in the Philosophical Transactions of 1758 and 1765. An important finding of this investigation is that a particular form of the achromatic lens that has been suggested as being a rare and early form by some investigators, and presumably introduced by Chester Moor Hall, was in fact found to be numerous and present in most museums and many private collections. It is shown that the colour correction of an early eighteenth-century doublet telescope objective is very sensitive to the ratio of the flint to crown glass focal lengths, as well as the variations of the indices of refraction with colour. This sensitivity would preclude any simple recipe for constructing an achromatic lens. The third order theory of spherical aberration of Nevil Maskelyne is reexamined, in which he pointed out that John Dollond developed a theoretical formula equivalent to what today is called geometric third order spherical aberration theory. (shrink)

The thresholds of human observers detecting line targets improve significantly when the targets are presented in a spatial context of collinear inducing stimuli. This phenomenon is referred to as spatial facilitation, and may reflect the output of long-range interactions between cortical feature detectors. Spatial facilitation has thus far been observed with luminance-defined, achromatic stimuli on achromatic backgrounds. This study compares spatial facilitation with line targets and collinear, edge-like inducers defined by luminance contrast to spatial facilitation with targets and inducers defined (...) by color contrast. The results of a first experiment show that achromatic inducers facilitate the detection of achromatic targets on gray and colored backgrounds, but tend to suppress the detection of chromatic targets. Chromatic inducers facilitate the detection of chromatic targets on gray and colored backgrounds, but tend to suppress the detection of achromatic targets. Chromatic spatial facilitation appears to be strongest when inducers and background are isoluminant. The results of a second experiment show that spatial facilitation with chromatic targets and inducers requires a longer exposure duration of the inducers than spatial facilitation with achromatic targets and inducers, which is already fully effective at an inducer exposure of 30 ms only. The findings point towards two separate mechanisms for spatial facilitation with collinear form stimuli: one that operates in the domain of luminance, and one that operates in the domain of color contrast. These results are consistent with neural models of boundary and surface formation which suggest that achromatic and chromatic visual cues are represented on different cortical surface representations that are capable of selectively attracting attention. Multiple copies of these achromatic and chromatic surface representations exist corresponding to different ranges of perceived depth from an observer, and each can attract attention to itself. Color and contrast differences between inducing and test stimuli, and transient responses to inducing stimuli, can cause attention to shift across these surface representations in ways that sometimes enhance and sometimes interfere with target detection. (shrink)

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. (shrink)

��Grapheme-color synaesthesia is a neurological phenomenon in which particular graphemes, such as the numeral 9, automatically induce the simultaneous perception of a particular color, such as the color red. To test whether the concurrent color sensations in graphemecolor synaesthesia are treated as meaningful stimuli, we recorded event-related brain potentials as 8 synaesthetes and 8 matched control subjects read sentences such as ‘‘Looking very clear, the lake was the most beautiful hue of 7.’’ In synaesthetes, but not (...) control subjects, congruous graphemes, compared with incongruous graphemes, elicited a more negative N1 component, a less positive P2 component, and a less negative N400 component. Thus, contextual congruity of synaesthetically induced colors altered the brain response to achromatic graphemes beginning 100 ms postonset, affecting pattern-recognition, perceptual, and meaning-integration processes. The results suggest that grapheme-color synaesthesia is automatic and perceptual in nature and also suggest that the connections between colors and numbers are bidirectional. (shrink)

Brown highlights cases of “chromatic layering”—scenarios in which one perceives an opaque object through a transparent volume/film/filter with a chromatic or achromatic content of its own—as a way of reining in the argument from perceptual variation sometimes used to motivate a relationalist account of color properties. Brown urges that the argument in question does not generalize smoothly to all types of perceptual variation—in particular, that it fits poorly in layering cases in which there is either experiential fusion or scission. (...) While he doesn’t want to reject the relationalist description of variation in all cases, he does suggest that there is an alternative, and preferable, description available for layering cases, and that the availability of this alternative puts limits on the scope of both relationalist arguments and relationalist conclusions. I claim that the obstacles for the argument from perceptual variation posed by cases of layering are merely apparent. I argue that relationalism can be extended smoothly to cases of layering, and indeed that denying this extension, as Brown proposes, contravenes ordinary and more or less universally accepted canons of rational inquiry. (shrink)

There is no evidence to suggest that even as late as January 1672, when Newton was elected a Fellow of the Royal Society, anyone had any inkling of his new theory of colours. His name exploded on the scientific scene as the inventor and constructor of a new kind of telescope—what later became known as the reflector . Had the erudition of the London virtuosi been a little broader, they would have known that in fact he was not the inventor (...) of the telescope, even though the precise form he gave it was his. Not only was the idea a hundred years old, during which period it was repeatedly suggested by various writers, but also Newton himself took the idea straight from the most recent of these suggestions, namely that included in James Gregory's Optica promota of 1663. The situation becomes even more ironic when we realize that the new instrument was admired for wrong reasons and on merits that were far from Newton's intentions. Nevertheless, admired it was, and there was a good reason for this: Newton's instrument was in fact the first reflector actually to be constructed and, moreover, for a few weeks it performed quite well. Several astonomers became interested because of the high magnifying power relative to its dimensions. (shrink)

We have used fMRI to measure responses to chromatic and achromatic contrast in retinotopically defined regions of macaque and human visual cortex. We make four observations. Firstly, the relative amplitudes of responses to color and luminance stimuli in macaque area V1 are similar to those previously observed in human fMRI experiments. Secondly, the dorsal and ventral subdivisions of macaque area V4 respond in a similar way to opponent (L j M)-cone chromatic contrast suggesting that they are part of a (...) single functional area. Thirdly, we find that macaque area V4, like area V1, responds preferentially to chromatic contrast compared to luminance contrast and the degree of preference is strongly influenced by the temporal frequency of the stimulus. Finally, we observe that while macaque V4d is a region on the dorsal surface of the macaque visual cortex that responds robustly to chromatic stimuli, human chromatic responses to identical stimuli are largely confined to the ventral surface suggesting a fundamental difference in the topographical organization of higher visual areas between humans and macaques. (shrink)

Colour synaesthesia is the mental experience involving a strong association between specific colours and specific auditory stimuli, such as words, or achromatic visual stimuli, such as numerals or letters. In the contemporary literature on colour synaesthesia, the majority view treats the phenomenon as one arising from some of the same neural events mediating colour perception triggered by genuinely coloured objects; this view that synaesthesia is perceptually based, however, is not universally endorsed. What strategies have been utilized to evaluate the perceptual (...) reality of colour synaesthesia, and what is the evidence produced by those strategies? This chapter tackles those questions within the context of colour graphemic synaesthesia, the most widely studied form of synaesthesia. We divide the research strategies into those employing behavioral measures to assess whether synaesthetia influences performance on tasks known to be sensitive stimulus colour and those employing indirect measures that use physiological responses as proxies for colour perception. Our chapter concludes that there is sufficient justification for the belief in the perceptual reality of colour grapheme synaesthesia. At the same time, we applaud those who remain disbelievers, for their skepticism has underscored the logical issues surrounding research on this question. (shrink)

Two experiments compared “Red-Green” dichromats’ empirical and metacognized capacities to discriminate basic color categories and to use the corresponding basic color terms. A first experiment used a 102-related-colors set for a pointing task to identify all the stimuli that could be named with each BCT by each R-G dichromat type. In a second experiment, a group of R-G dichromats estimated their difficulty discriminating BCCs-BCTs in a verbal task. The strong coincidences between the results derived from the pointing and (...) the verbal tasks indicated that R-G dichromats have very accurate metacognition about their capacities and limitations in the use of BCTs. Multidimensional scaling solutions derived from both tasks were very similar: BCTs in R-G dichromats were properly represented in 2D MDS solutions that clearly show one chromatic dimension and one achromatic dimension. Important concordances were found between protanopes and deuteranopes. None of these dichromats showed substantial difficulty discriminating the Red-Green pair. So, to name them “R-G” dichromats is misleading considering their empirical capacities and their metacognition. Further reasons to propose the use of the alternative denomination “Brown-Green” dichromats are also discussed. We found some relevant differences between the “Brown-Green” dichromats’ empirical and self-reported difficulties using BCTs. Their metacognition can be considered a “caricature” of their practical difficulties. This caricature omits some difficulties including their problems differentiating “white” and “black” from other BCTs, while they overestimate their limitations in differentiating the most difficult pairs. Individual differences scaling analyses indicated that the metacognition regarding the use of BCTs in “Brown-Green” dichromats, especially deuteranopes, is driven slightly more by the chromatic dimension and driven slightly less by the achromatic dimension, than their practical use of BCTs. We discuss the relevance of our results in the framework of the debate between the linguistic relativity hypothesis and the universal evolution theories. (shrink)

In psychophysical experiments, the use of a psychophysical procedure of brightness/darkness cancellation shed light on interactions between spatial arrangement and figure–ground contrast in the perceptual filling in of achromatic and colored surfaces.Achromatic and chromatic Kanizsa squares with varying contrast, contrast polarity, and inducer spacingwere used to test how these factors interact in the perceptual filling in of surface brightness or darkness. The results suggest that the neuronal processing of surfaces with apparent contrast, leading to figure–ground segregation (i.e., perceptual organization), is (...) governed by mechanisms that integrate both luminance contrast and spatial information carried by the inducing stimuli, while discarding information on contrast polarity or color. The findings are discussed in relation to earlier observations on brightness assimilation and contrast. They support theories of nonantagonistic neural mechanisms suppressing local contrast or color signs in brightnessbased figure–ground percepts. Such mechanismsmight be necessary to cancel potentially conflicting polarities in geometricallycomplex visual stimuli so that perceptual filling in resulting in the most plausible representation of figure and ground can be achieved. (shrink)

People with grapheme-color synesthesia perceive specific colors when viewing different letters or numbers. Previous studies have suggested that synesthetic color experience can be bistable when induced by an ambiguous character. However, the exact relationship between processes underlying the identity of an alphanumeric character and the experience of the induced synesthetic color has not been examined. In the present study, we explored this by focusing on the temporal relation of inducer identification and color emergence using inducers whose (...) identity could be rendered ambiguous upon rotation of the characters. Specifically, achromatic alphabetic letters and digits were presented at varying angles to 9 grapheme-color synesthetes. Results showed that grapheme identification and synesthetically perceived grapheme color covary with the orientation of the test stimulus and that synesthetes were slower naming the experienced color than identifying the character, particularly at intermediate angles where ambiguity was greatest. (shrink)

We show that true colors as defined by Chevreul (1839) produce unsuspected simultaneous brightness induction effects on their immediate grey backgrounds when these are placed on a darker (black) general background surrounding two spatially separated configurations. Assimilation and apparent contrast may occur in one and the same stimulus display. We examined the possible link between these effects and the perceived depth of the color patterns which induce them as a function of their luminance contrast. Patterns of square-shaped inducers of (...) a single color (red, green, blue, yellow, or grey) were placed on background fields of a lighter and a darker grey, presented on a darker screen. Inducers were always darker on one side of the display and brighter on the other in a given trial. The intensity of the grey backgrounds varied between trials only. This permitted generating four inducer luminance contrasts, presented in random order, for each color. Background fields were either spatially separated or consisted of a single grey field on the black screen. Experiments were run under three environmental conditions: dark-adaptation, daylight, and rod-saturation after exposure to bright light. In a first task, we measured probabilities of contrast, assimilation, and no effect in a three-alternative forced-choice procedure (background appears brighter on the ‘left’, on the ‘right’ or the ‘same’). Visual adaptation and inducer contrast had no significant influence on the induction effects produced by colored inducers. Achromatic inducers produced significantly stronger contrast effects after dark-adaptation, and significantly stronger assimilation in daylight conditions. Grouping two backgrounds into a single one was found to significantly decrease probabilities of apparent contrast. Under the same conditions, we measured probabilities of the inducers to be perceived as nearer to the observer inducers. These, as predicted by Chevreul’s law of contrast, were determined by the luminance contrast of the inducers only, with significantly higher probabilities of brighter inducers to be seen as nearer, and a marked asymmetry between effects produced by inducers of opposite sign. Implications of these findings for theories which attempt to link simultaneous induction effects to the relative depth of object surfaces in the visual field are discussed. (shrink)

Spatial facilitation has been observed with luminance-defined, achromatic stimuli on achromatic backgrounds as well as with targets and inducers defined by colour contrast. This paper reviews psychophysical results from detection experiments with human observers showing the conditions under which spatially separated contour inducers facilitate the detection of simultaneously presented target stimuli. The findings point towards two types of spatial mechanisms: (i) Short-range mechanisms that are sensitive to narrowly spaced stimuli of small size and, at distinct target locations, selective to the (...) contrast polarity of targets and inducers. (ii) Long-range mechanisms that are triggered by longer stimuli, generate facilitation across wider spatial gaps between targets and inducers, and are insensitive to their contrast polarity. Spatial facilitation with chromatic stimuli requires a longer inducer exposure than spatial facilitation with achromatic stimuli, which is already fully effective at inducer exposures of 30 ms. This difference in temporal dynamics indicates some functional segregation between mechanisms for colour and luminance contrast in the perception of space. (shrink)

Recent research on grapheme-colour synesthesia has focused on whether visual attention is necessary to induce a synesthetic percept. The current study investigated the influence of synesthesia on overt visual attention during an oculomotor target selection task. Chromatic and achromatic stimuli were presented with one target among distractors among multiple ‘5’s ). Participants executed an eye movement to the target. Synesthetes and controls showed a comparable target selection performance across conditions and a ‘pop-out effect’ was only seen in the chromatic condition. (...) As a pop-out effect was absent for the synesthetes in the achromatic condition, a synesthetic element appears not to elicit a synesthetic colour, even when it is the target. The synesthetic percepts are not pre-attentively available to distinguish the synesthetic target from synesthetic distractors when elements are presented in the periphery. Synesthesia appears to require full recognition to bind form and colour. (shrink)

Where are we to look for the unique hues? Out in the world? In the eye? In more central processing? 1. There are difficulties looking for the structure of the unique hues in simple combinations of cone-response functions like ( L − M ) and ( S − ( L + M )): such functions may fit pretty well the early physiological processing, but they don’t correspond to the structure of unique hues. It may seem more promising to look to, (...) e.g., Hurvich & Jameson’s ‘chromatic response functions’; but these report on psychophysical behaviour, not on underlying physiology. So ‘opponent processing’ isn’t any particular help on the unique hues—and even physiology in general seems not to have come up with any good correlate or explanation. 2. Wright ( Review of Philosophy and Psychology 2: 1–17, 2011 ) looks in a different place: to (a) magnitude of total visual response that a stimulus light provokes, the maxima and minima of which, he thinks, give us the boundaries of the main hue categories (Wright connects these with Thornton’s ‘prime’ and ‘antiprime’ colours in an illuminant: Journal of the Optical Society of America 61 ( 1971 ): 1155–1163); and (b) the ratio of chromatic to achromatic response, the maxima and minima of which, he suggests, give us the focal points of the unique hues. The suggestions are extremely interesting; but the desired correspondences have some counterexamples; and where they hold, one could wonder how much they depend upon the particular choice of functions to measure (a) and (b); and one could hope for more of an explanatory linkage between the sets of items in question. 3. Could the unique hues come from, so to speak, the external world? White and black can easily be defined as particular kinds of reflectance. What of the standard four unique hues? Variation in kinds of sunlight and skylight coincides well with variation along a line from unique yellow to unique blue (cf. Shepard 1992 , Mollon 2006 ). If we wanted something to calibrate our standards for unique yellow and blue as the lens of the eye changes with age, and despite interpersonal cone differences, this would be a good basis—and there are several ways this can be extended to surface colours. But is there any essential connection between these things: is there any rationale why the light of the sun and the sky should be counted as unique hued ? An answer may be: because in our environment, these illuminants are as close to white (or the natural illuminant colour) as you can get—to see things tinged with sunlight or skylight should be to see them minimally tinged with any alien colour. Whereas other hues in an illuminant would be treated as tinging with a more alien colour the thing seen. (shrink)

This paper argues that the distinctiveness of the Hering primary hues—red, green, blue, and yellow—is already evident at the retina. Basic features of spectral sensitivity provide a foundation for the development of unique hue perceptions and the hue categories of which they are focal examples. Of particular importance are locations in color space at which points of minimal and maximal spectral sensitivity and extreme ratios of chromatic to achromatic response occur. This account builds on Jameson and D’Andrade’s (1997) insight (...) about the relationship between the Hering primaries and chromatic/achromatic ratios, Romney and Chiao’s (2009) color appearance model, and Thornton’s (1971, 1999) research on artificial lighting. (shrink)

Mechanisms of attention play a crucial role in filtering sensory inputs from the external world, allowing information to be prioritised for goal directed behaviour. To what extent might these same capacity-limited processes influence grapheme-colour synaesthesia, in which letters, numbers or words evoke concurrent experiences of colour? Asking synaesthetes themselves whether attention seems important in their experiences has provided a range of answers. On the one hand, for some synaesthetes, diverting attention can diminish the quality of their synaesthetic colours. On the (...) other, there are suggestions that synaesthetic experiences can themselves alter the manner in which attention is allocated to sensory stimuli in the environment. Here, we review a range of empirical investigations that have examined the role of attention in grapheme-colour synaesthesia. A particular focus of these studies has been the extent to which an inducing stimulus - such as an achromatic letter or digit - must be attended or consciously perceived to trigger a concurrent synaesthetic experience. In most cases, limiting attention or masking inducers tends to reduce or eliminate behavioural evidence of synaesthetic experiences. We also discuss how synaesthesia might improve performance in visual search tasks through post-attentive processes such as grouping, or by facilitating decision-making processes. (shrink)

Erickson's conclusion that if basic tastes are not appropriate at one level, reference to labeled lines is inappropriate at any level, depends on matters of definition and scope. His population model mirrors Young's theory of color perception. However, there is evidence for distinct pathways to the cortex for two cone-opponent and one achromatic channel. Depending on the use made of key terms, sensory systems may display both across-fiber and labeled-line features.

Central to Wilfrid Sellars ' philosophical system is his belief that science's current ontology is inadequate as it fails to provide for an acceptable account of perceptual experience. Unfortunately, this remains the most puzzling plank in his philosophy. Sellars himself argues for this position via his wellknown example of a pink ice cube and its homogeneous colour. This homogeneity, says Sellars, bars the acceptance of science's present ontology of achromatic particles, and requires the introduction of items which are truly coloured. (...) Only with such a revised and expanded ontology, with all that entails, can science adequately meet its explanatory demands. I aim here to remedy at least some of the confusions and misunderstandings this position has engendered. But I mean to take a different route from Sellars. In short, given the problems with Sellars ' views on homogeneity, I will argue for the Sellarsian conclusion as to the inadequacy of present scientific ontologies, yet without reliance on the puzzling doctrine of homogeneity. I begin then with a detailed examination of Sellars official position, indicate the trouble spots, and begin an alternative route. As I conceive things, however, the position I will sketch is still thoroughly Sellarsian, for it proceeds from premises Sellars himself has endorsed. (shrink)

This paper argues that the distinctiveness of the Hering primary hues – red, green, blue, and yellow – is already evident at the retina. Basic features of spectral sensitivity provide a foundation for the development of unique hue perceptions and the hue categories of which they are focal examples. Of particular importance are locations in color space at which points of minimal and maximal spectral sensitivity and extreme ratios of chromatic to achromatic response occur. This account builds on Jameson (...) & D’Andrade’s (1997) insight about the relationship between the Hering primaries and chromatic/achromatic ratios, Romney & Chiao’s (2009) color appearance model, and Thornton’s (1971; 1999) research on artificial lighting. (shrink)

A Naive Realist Theory of Colour defends the view that colours are mind-independent properties of things in the environment, that are distinct from properties identified by the physical sciences. This view stands in contrast to the long-standing and wide-spread view amongst philosophers and scientists that colours don't really exist - or at any rate, that if they do exist, then they are radically different from the way that they appear. It is argued that a naive realist theory of colour best (...) explains how colours appear to perceiving subjects, and that this view is not undermined either by reflecting on variations in colour perception between perceivers and across perceptual conditions, or by our modern scientific understanding of the world. A Naive Realist Theory of Colour also illustrates how our understanding of what colours are has far-reaching implications for wider questions about the nature of perceptual experience, the relationship between mind and world, the problem of consciousness, the apparent tension between common sense and scientific representations of the world, and even the very nature and possibility of philosophical inquiry. (shrink)

Can the phenomenal character of perceptual experience be altered by the states of one's cognitive system, for example, one's thoughts or beliefs? If one thinks that this can happen then one thinks that there can be cognitive penetration of perceptual experience; otherwise, one thinks that perceptual experience is cognitively impenetrable. I claim that there is one alleged case of cognitive penetration that cannot be explained away by the standard strategies one can typically use to explain away alleged cases. The case (...) is one in which it seems subjects' beliefs about the typical colour of objects affects their colour experience. I propose a two-step mechanism of indirect cognitive penetration that explains how cognitive penetration may occur. I show that there is independent evidence that each step in this process can occur. I suspect that people who are opposed to the idea that perceptual experience is cognitively penetrable will be less opposed to the idea when they come to consider this indirect mechanism and that those who are generally sympathetic to the idea of cognitive penetrability will welcome the elucidation of this plausible mechanism. (shrink)

Sexual dimorphism, symmetry, and coloration in human faces putatively signal information relevant to mate selection and reproduction. Although the independent contributions of these characteristics to judgments of attractiveness are well established, relatively few studies have examined whether individuals prioritize certain features over others. Here, participants (N = 542, 315 female) ranked six sets of facial photographs (3 male, 3 female) by their preference for starting long- and short-term romantic relationships with each person depicted. Composite-based digital transformations were applied such that (...) each image set contained 11 different versions of the same identity. Each photograph in each image set had a unique combination of three traits: sexual dimorphism, symmetry, and color cues to health. Using conjoint analysis to evaluate participants’ ranking decisions, we found that participants prioritized cues to sexual dimorphism over symmetry and color cues to health. Sexual dimorphism was also found to be relatively more important for the evaluation of male faces than for female faces, whereas symmetry and color cues to health were relatively more important for the evaluation of female faces than for male faces. Symmetry and color cues to health were more important for long-term versus short-term evaluations for female faces, but not male faces. Analyses of utility estimates reveal that our data are consistent with research showing that preferences for facial masculinity and femininity in male and female faces vary according to relationship context. These findings are interpreted in the context of previous work examining the influence of these facial attributes on romantic partner perception. (shrink)

Interrogating received knowledge is constitutive to any critical project, and recently there has been a wave of scholarship which argues for locating the origin of racist-thinking prior to modern Europe—even prior to the Common Era—without any real consideration of the potential dangers accompanying such a seismic redefinition. By expanding “racism” to include potentially any pre-modern xenophobic or ethnicist atrocity, even well-meaning scholarship dilutes the peculiar injustice of modern Europe’s most successful epistemological weapon. As a result, we lose any criteria to (...) distinguish ubiquitous oppressive projects from specifically racist-projects of hegemony and domination. However laudable its intent, such scholarship falls prey to methodological, epistemological, and practical errors that hamstring the ameliorative impact of contemporary anti-racist work while ironically diminishing racism’s impact. For if every conflict is racist, then contemporary colorblindness is correct: if white supremacy isn’t particularly white, then racism is a distinction without a difference. (shrink)

Philosophical Investigations, Volume 45, Issue 2, Page 107-129, April 2022.

색채 문제는 비트겐슈타인의 철학 발전과 관련해 중요한 의의를 지니는 문제이다. 그것은 그가 자신의 전기 철학 체계를 해체하고 후기의 보다 풍부한 사유로 나아가게 된 계기가 된 문제이면서, 그가 철학적 전환 이후에도 새로운 관점에서 말년에 이르기까지 계속 관심을 가지고 고찰한 문제였다. 이 글은 이른바 색깔 배제가 제기하는 논리적 문제들로부터 시작하여, 이 문제를 해결하려는 그의 이른바 중기의 ‘현상학적’ 시도와 포기, 그리고 그가 최종적으로 『색채에 관한 소견들』에 이르러 도달한 색채의 문법에 대한 생각들을 살펴보려 한다. 나는 특히 그의 탐구가 논리적인 것에서 문법적인 것으로 전환하는 과정과 (...) 그 후 그 문법적인 것에 (여전히) 남아 있는 논리적 성격을 유의해 볼 것이다. (shrink)

The words “content” and “character” in my title refer to the representational content and phenomenal character of color experiences. So my topic concerns the nature of our experience of color. But I will, of course, be talking about colors as well as color experience. Let me set the stage by mentioning some things, some more controversial than others, that I will be taking for granted. I assume, to begin with, that objects in the world have colors, and (...) have them independently of being perceived to have them, and independently even of there being creatures capable of perceiving them. I think, and this of course sets me apart from the many color irrealists among philosophers and color scientists, that any reasonable semantics for color terms, and any reasonable account of the reference of color concepts, should yield the result that colors are properties of external things that are realized in certain of their physical properties, namely those responsible for their reflecting or emitting the light whose impact on our retinas is involved in causing our color perceptions. This brings me to a further assumption that I shall be making, namely the truth of physicalism. I take physicalism to be the thesis that all properties of things either are or are realized in basic physical properties, where basic physical properties are the properties that underlie the behavior and causal powers of inanimate things. There are two ways in which the commitment to physicalism will figure in my discussion. First, I assume that colors are physically realized properties. Second, I assume that color experiences are physically realized. These two commitments frame the problem I am discussing – how can colors be properties realized in the microphysical properties of things, and how can color experience be so realized? I don’t think there is any generally accepted account of what it is for a property to be “realized in” other properties. For those who think, as I do, that properties are individuated by their causal features, it should seem plausible to say that property P realizes property Q just in case the forward looking causal features of Q are a subset of the forward looking causal features of P, and the backward looking.... (shrink)

Philosophical Papers, Volume 41, Issue 2, Page 305-321, July 2012.

Over the last 25 years, there has been a concerted effort to settle questions about multiple realization by bringing detailed scientific evidence to bear. Ken Aizawa and Carl Gillett have pursued this scientific approach to multiple realization with a precise theory and applications. This paper reviews the application of the Dimensioned approach to human color vision, addressing objections that have appeared in the literature.

Social justice is put forth as a core professional nursing value, although conceptualizations within foundational documents and among nurse educators remain inconsistent and contradictory. The purpose of this study was to explore how faculty teach social justice in theory courses in Baccalaureate programs. This qualitative study utilized constructivist grounded theory methods to examine processes informing participants' teaching. Participants utilize four overarching approaches: fostering engaging classroom climates, utilizing various naming strategies, framing diversity and culture as social justice, and role modeling a (...) critical stance. They deploy specific strategies, varying largely by race, educational background, and nursing specialty. A background in social sciences supports pedagogy that interrogates health inequities rather than merely raising awareness about disparities. Findings also reveal that faculty of color navigate institutional structures predicated upon colorblind racism and problematic views of culture, which many white faculty teaching non‐Community Health Nursing courses described doing. To enact social justice and be answerable to our communities, concerted anti‐oppression efforts are needed across education, research, practice, and policy. This includes sustained commitment to address colonialism and whiteness in every institution that defines, promotes, and claims to advance nursing so that we can fulfill our responsibility to address unjust systems and structures to serve our communities. (shrink)

The verb “to conjure” is a complex one, for it includes in its standard definition a great range of possible actions or operations, not all of them equivalent, or even compatible. In its most common usage, “to conjure” means to perform an act of magic or to invoke a supernatural force, by casting a spell, say, or performing a particular ritual or rite. But “to conjure” is also to influence, to beg, to command or constrain, to charm, to bewitch, to (...) move or convey, to imagine, to visualize, to call to mind, or to remember. —Rachael DeLue 2012, para 1.When we create with our Brown hands, feminine energy, and full spirits, we conjure. To exist, survive, and thrive in these bodies is a continuous act of conjuring. Our walks conjure. Our smiles conjure. Our tears conjure. Our laughs conjure. Our words conjure. Our artworks are conjurings. We, a Black/Filipina-American woman, a Dominican-American, and a Black-American woman, are guided by our solidarity with one another and all other Black and Brown female identifying persons whose raced and gendered subjectivities exist both inside and outside of colonization, white supremacy, and patriarchy. We bring to life our colored imaginations and curiosities, and share them with the world. We are united by our need for safety, autonomy as beings, dissolution of trauma, and desire to ask, “What would happen if I…?” Imaginative, curious Women of Color founded the underground railroad, guided captured Africans and Tainos to the mountains, ignited the Civil Rights Movement, organized laborers and immigrants, birthed the #BlackLivesMatter Movement, conceived the #MeToo Movement, and so much more. Like our kindred counterparts, we have an unrelenting urge to examine, question, wonder, desire, speak to, lead, be curious, and “conjure.” As practicing artists and art educators, our critical arts-based practices are grounded in intersectional feminisms like Womanism, Black Feminist Theory, and Chicana Feminist Theory, which allow us to do these very things. (shrink)

Multisensory stimulation has been shown to alter the sense of body-ownership. Given that perceived similarity between one’s own body and those of others is crucial for social cognition, we investigated whether multisensory stimulation can lead participants to experience ownership over a hand of different skin colour. Results from two studies using introspective, behavioural and physiological methods show that, following synchronous visuotactile stimulation, participants can experience body-ownership over hands that seem to belong to a different racial group. Interestingly, a baseline measure (...) of implicit racial bias did not predict whether participants would experience the RHI, but the overall strength of experienced body-ownership seemed to predict the participants’ post-illusion implicit racial bias with those who experienced a stronger RHI showing a lower bias. These findings suggest that multisensory experiences can override strict ingroup/outgroup distinctions based on skin colour and point to a key role for sensory processing in social cognition. (shrink)

The standard adaptationist explanation of the presence of a sensory mechanism in an organism—that it detects properties useful to the organism—cannot be given for color vision. This is because colors do not exist. After arguing for this latter claim, I consider, but reject, nonadaptationist explanations. I conclude by proposing an explanation of how color vision could have adaptive value even though it does not detect properties in the environment.

I offer a new objectivist theory of the contents of color language and color experience, intended especially as an account of what normal intersubjective variation in color perception and classification shows about those contents. First I explain an abstract account of the contents of color and other gradable adjectives; on the account, these contents are certain objective properties constituted in part by contextually intended standards of application, which are in turn values in the dimensions of variation (...) associated with the adjectives. Then I propose an explanation of normal variations in linguistic color classification; these are postulated to be effects of differences in intended standards for the color adjectives appearing in the classifying predicates. Next, I consider a potential objection to this explanation, based on the suggestion that contextual content should be more accessible than the explanation predicts. In reply, I point out that contextual content is occasionally opaque to unsophisticated reflection. Finally, I present a companion account of the contents of color experiences on which these represent an object as lying on certain salient intervals in the chromatic dimensions, and I show how the account accommodates intersubjective variation in color perception. (shrink)

On 24 July 2022, the landmark decision Roe v. Wade (1973), that secured a right to abortion for decades, was overruled by the US Supreme Court. The Court decision in Dobbs v. Jackson Women’s Health Organisation severely restricts access to legal abortion care in the USA, since it will give the states the power to ban abortion. It has been claimed that overruling Roe will have disproportionate impacts on women of color and that restricting access to abortion contributes to (...) or amounts to structural racism. In this paper, we consider whether restricting abortion access as a consequence of overruling Roe could be understood as discrimination against women of color (and women in general). We argue that banning abortion is indirectly discriminatory against women of color and directly (but neither indirectly, nor structurally) discriminatory against women in general. (shrink)

Some philosophical theories of the nature of color aim to respect a "common sense" conception of color: aligning with the common sense conception is supposed to speak in favor of a theory and conflicting with it is supposed to speak against a theory. In this paper, we argue that the idea of a "common sense" conception of color that philosophers of color have relied upon is overly simplistic. By drawing on experimental and historical evidence, we show (...) how conceptions of color vary along several dimensions and how even supposedly "core" components of the contemporary "common sense" conception of color are less stable than they have been thought to be. (shrink)