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Trukša R, Fomins S, Jansone-Langina Z, Tenisa L. Colour Vision Changes across Lifespan: Insights from FM100 and CAD Tests. Vision (Basel) 2024; 8:53. [PMID: 39311321 PMCID: PMC11417771 DOI: 10.3390/vision8030053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 08/14/2024] [Accepted: 08/30/2024] [Indexed: 09/26/2024] Open
Abstract
(1) Background: in this research study, colour vision was evaluated in individuals aged 19 to 70 years with and without red-green colour vision disorders. (2) Methods: study participant colour vision was assessed with anomaloscope, HRR, FM100 hue, and CAD tests. (3) Results: No significant correlation was found between participant age and chromatic sensitivity of the red-green colour opponent channel. However, a decrease in blue-yellow colour opponent channel chromatic sensitivity was confirmed with the FM100 hue test and CAD test. Analysis of FM100 hue test error scores across age groups revealed a decline in chromatic sensitivity in the short-wave region of visible light with increasing age. Comparison of the colour-deficient individual results of the CAD and anomaloscope tests confirmed that CAD test sensitivity and specificity reaches 100%. However, some individuals with deutan-type deficits were misclassified as having protan-type deficits. This study confirmed the effectiveness of the FM100 test in identifying individuals with moderate to severe colour vision deficits, with sensitivity and specificity rates of 81.25% and 95.38%. (4) Conclusions: It was found that the FM100 hue test effectively identifies individuals with moderate and severe red-green colour vision deficiencies. On the other hand, individuals with mild colour vision deficiencies may go undetected with the FM100 hue test.
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Affiliation(s)
- Renārs Trukša
- Department of Optometry and Vision Science, Faculty of Science and Technology, University of Latvia, LV-1004 Riga, Latvia; (Z.J.-L.); (L.T.)
| | - Sergejs Fomins
- Institute of Solid-State Physics, University of Latvia, LV-1063 Riga, Latvia;
| | - Zane Jansone-Langina
- Department of Optometry and Vision Science, Faculty of Science and Technology, University of Latvia, LV-1004 Riga, Latvia; (Z.J.-L.); (L.T.)
| | - Laura Tenisa
- Department of Optometry and Vision Science, Faculty of Science and Technology, University of Latvia, LV-1004 Riga, Latvia; (Z.J.-L.); (L.T.)
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2
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Greene MJ, Boehm AE, Vanston JE, Pandiyan VP, Sabesan R, Tuten WS. Unique yellow shifts for small and brief stimuli in the central retina. J Vis 2024; 24:2. [PMID: 38833255 PMCID: PMC11156209 DOI: 10.1167/jov.24.6.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 05/01/2024] [Indexed: 06/06/2024] Open
Abstract
The spectral locus of unique yellow was determined for flashes of different sizes (<11 arcmin) and durations (<500 ms) presented in and near the fovea. An adaptive optics scanning laser ophthalmoscope was used to minimize the effects of higher-order aberrations during simultaneous stimulus delivery and retinal imaging. In certain subjects, parafoveal cones were classified as L, M, or S, which permitted the comparison of unique yellow measurements with variations in local L/M ratios within and between observers. Unique yellow shifted to longer wavelengths as stimulus size or duration was reduced. This effect is most pronounced for changes in size and more apparent in the fovea than in the parafovea. The observed variations in unique yellow are not entirely predicted from variations in L/M ratio and therefore implicate neural processes beyond photoreception.
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Affiliation(s)
- Maxwell J Greene
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, USA
| | - Alexandra E Boehm
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, USA
| | - John E Vanston
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, USA
| | - Vimal P Pandiyan
- Department of Ophthalmology, University of Washington, Seattle, WA, USA
| | - Ramkumar Sabesan
- Department of Ophthalmology, University of Washington, Seattle, WA, USA
| | - William S Tuten
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, USA
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3
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Somers LP, Franklin A, Bosten JM. Empirical tests of the effectiveness of EnChroma multi-notch filters for enhancing color vision in deuteranomaly. Vision Res 2024; 218:108390. [PMID: 38531192 DOI: 10.1016/j.visres.2024.108390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 03/11/2024] [Accepted: 03/16/2024] [Indexed: 03/28/2024]
Abstract
Manufacturers of notch filter-based aids for color vision claim that their products can enhance color perception for people with anomalous trichromacy, a form of color vision deficiency (CVD). Anecdotal reports imply that people with CVD can have radically enhanced color vision when using the filters. However, existing empirical research largely focussed on the effect of notch filters on performance on diagnostic tests for CVD has not found that they have any substantial effect. Informed by a model of anomalous trichromatic color vision, we selected stimuli predicted to reveal the effects of EnChroma filters. Using these stimuli, we tested the ability of EnChroma filters to enhance color vision for 10 deuteranomalous trichromats in three experiments: 1. asymmetric color matching between test and control filter conditions, 2. color discrimination measured using four alternative forced-choice, and 3. color appearance measured using dissimilarity ratings to reconstruct subjective color spaces using multidimensional scaling. To investigate potential effects of long-term adaptation or perceptual learning, participants completed all three experiments at two time points, on first exposure to the filters, and after a week of regular use. We found a significant effect of the filters on color matches in the direction predicted by the model at both time points, implying that the filters can enhance the anomalous trichromatic color gamut. However, we found minimal effect of the filters on color discrimination at threshold. We found a significant effect of the filters in enhancing the appearance of colors along the red-green axis at the first time point, and a trend in the same direction at the second time point. Our results provide the first quantitative experimental evidence that notch filters can enhance color perception for anomalous trichromats.
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Affiliation(s)
- Lucy P Somers
- Sussex Vision Lab, School of Psychology, University of Sussex, Falmer, UK
| | - Anna Franklin
- Sussex Baby Lab and Sussex Colour Group, School of Psychology, University of Sussex, Falmer, UK
| | - Jenny M Bosten
- Sussex Vision Lab, School of Psychology, University of Sussex, Falmer, UK.
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4
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Somers LP, Bosten JM. Predicted effectiveness of EnChroma multi-notch filters for enhancing color perception in anomalous trichromats. Vision Res 2024; 218:108381. [PMID: 38522412 DOI: 10.1016/j.visres.2024.108381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 03/08/2024] [Accepted: 03/09/2024] [Indexed: 03/26/2024]
Abstract
EnChroma filters are aids designed to improve color vision for anomalous trichromats. Their use is controversial because the results of lab-based assessments of their effectiveness have so far largely failed to agree with positive anecdotal reports. However, the effectiveness of EnChroma filters will vary depending on the conditions of viewing, including whether the stimuli are broadband reflective surfaces or colors presented on RGB displays, whether illumination spectra are broadband or narrowband, the transmission spectra of particular filters, and the cone spectral sensitivity functions of the observer. We created a model of anomalous trichromatic color vision to predict the effects of EnChroma filters on the color signals impaired in anomalous trichromacy. Using the model we varied illumination, filter type and observer cone sensitivity functions, and tested the effect of presenting colors as broadband reflective surfaces or on RGB displays. We also used hyperspectral images to assess the impact of the filters on anomalous trichromats' color vision for natural scenes. Model results predicted that the filters should be broadly effective at enhancing anomalous trichromats' equivalent to L/(L + M) chromatic contrasts under a range of viewing conditions, but are substantially more effective for deuteranomals than for protanomals. The filters are predicted to be more effective for broadband reflective surfaces presented under broadband illuminants than for surfaces presented under narrowband illuminants or for colors presented on RGB displays. Since the potential impacts of contrast adaptation and perceptual learning are not considered in the model, it needs to be empirically validated. Results of empirical tests of the effects of EnChroma filters on deuteranomalous color vision in comparison with model predictions are presented in an accompanying paper (Somers et al., in prep.).
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Affiliation(s)
- Lucy P Somers
- Sussex Vision Lab, School of Psychology, University of Sussex, Falmer, UK
| | - Jenny M Bosten
- Sussex Vision Lab, School of Psychology, University of Sussex, Falmer, UK.
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5
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Lowndes R, Aveyard R, Welbourne LE, Wade A, Morland AB. In primary visual cortex fMRI responses to chromatic and achromatic stimuli are interdependent and predict contrast detection thresholds. Vision Res 2024; 218:108398. [PMID: 38552557 DOI: 10.1016/j.visres.2024.108398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/24/2024] [Accepted: 03/24/2024] [Indexed: 04/13/2024]
Abstract
Chromatic and achromatic signals in primary visual cortex have historically been considered independent of each other but have since shown evidence of interdependence. Here, we investigated the combination of two components of a stimulus; an achromatic dynamically changing check background and a chromatic (L-M or S cone) target grating. We found that combinations of chromatic and achromatic signals in primary visual cortex were interdependent, with the dynamic range of responses to chromatic contrast decreasing as achromatic contrast increased. A contrast detection threshold study also revealed interdependence of background and target, with increasing chromatic contrast detection thresholds as achromatic background contrast increased. A model that incorporated a normalising effect of achromatic contrast on chromatic responses, but not vice versa, best predicted our V1 data as well as behavioural thresholds. Further along the visual hierarchy, the dynamic range of chromatic responses was maintained when compared to achromatic responses, which became increasingly compressive.
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Affiliation(s)
- Rebecca Lowndes
- Department of Psychology, University of York, United Kingdom; York Neuroimaging Centre, University of York, United Kingdom.
| | - Richard Aveyard
- York Neuroimaging Centre, University of York, United Kingdom
| | - Lauren E Welbourne
- Department of Psychology, University of York, United Kingdom; York Neuroimaging Centre, University of York, United Kingdom
| | - Alex Wade
- Department of Psychology, University of York, United Kingdom; York Neuroimaging Centre, University of York, United Kingdom; York Biomedical Research Institute, University of York, United Kingdom
| | - Antony B Morland
- Department of Psychology, University of York, United Kingdom; York Neuroimaging Centre, University of York, United Kingdom; York Biomedical Research Institute, University of York, United Kingdom
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6
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Banks B, Borghi AM, Fargier R, Fini C, Jonauskaite D, Mazzuca C, Montalti M, Villani C, Woodin G. Consensus Paper: Current Perspectives on Abstract Concepts and Future Research Directions. J Cogn 2023; 6:62. [PMID: 37841672 PMCID: PMC10573588 DOI: 10.5334/joc.238] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 08/12/2022] [Indexed: 10/17/2023] Open
Abstract
concepts are relevant to a wide range of disciplines, including cognitive science, linguistics, psychology, cognitive, social, and affective neuroscience, and philosophy. This consensus paper synthesizes the work and views of researchers in the field, discussing current perspectives on theoretical and methodological issues, and recommendations for future research. In this paper, we urge researchers to go beyond the traditional abstract-concrete dichotomy and consider the multiple dimensions that characterize concepts (e.g., sensorimotor experience, social interaction, conceptual metaphor), as well as the mediating influence of linguistic and cultural context on conceptual representations. We also promote the use of interactive methods to investigate both the comprehension and production of abstract concepts, while also focusing on individual differences in conceptual representations. Overall, we argue that abstract concepts should be studied in a more nuanced way that takes into account their complexity and diversity, which should permit us a fuller, more holistic understanding of abstract cognition.
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Affiliation(s)
- Briony Banks
- Department of Psychology, Lancaster University, UK
| | - Anna M. Borghi
- Department of Dynamic and Clinical Psychology, and Health Studies, Sapienza University of Rome, Italy
- Institute of Cognitive Sciences and Technologies, Italian National Research Council, Rome, Italy
| | - Raphaël Fargier
- Department of Special Needs Education, University of Oslo, Norway
| | - Chiara Fini
- Department of Dynamic and Clinical Psychology, and Health Studies, Sapienza University of Rome, Italy
| | - Domicele Jonauskaite
- Faculty of Psychology, University of Vienna, Vienna, Austria
- Institute of Psychology, University of Lausanne, Lausanne, Switzerland
| | - Claudia Mazzuca
- Department of Dynamic and Clinical Psychology, and Health Studies, Sapienza University of Rome, Italy
| | - Martina Montalti
- Department of Clinical and Experimental Sciences, University of Brescia, Italy
- Department of Medicine and Surgery – Unit of Neuroscience, University of Parma, Italy
| | - Caterina Villani
- Department of Modern Languages, Literatures, and Cultures, University of Bologna, Italy
| | - Greg Woodin
- Department of English Language and Linguistics, University of Birmingham, UK
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7
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Hiramatsu C, Takashima T, Sakaguchi H, Chen X, Tajima S, Seno T, Kawamura S. Influence of colour vision on attention to, and impression of, complex aesthetic images. Proc Biol Sci 2023; 290:20231332. [PMID: 37700648 PMCID: PMC10498032 DOI: 10.1098/rspb.2023.1332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/17/2023] [Indexed: 09/14/2023] Open
Abstract
Humans exhibit colour vision variations due to genetic polymorphisms, with trichromacy being the most common, while some people are classified as dichromats. Whether genetic differences in colour vision affect the way of viewing complex images remains unknown. Here, we investigated how people with different colour vision focused their gaze on aesthetic paintings by eye-tracking while freely viewing digital rendering of paintings and assessed individual impressions through a decomposition analysis of adjective ratings for the images. Gaze-concentrated areas among trichromats were more highly correlated than those among dichromats. However, compared with the brief dichromatic experience with the simulated images, there was little effect of innate colour vision differences on impressions. These results indicate that chromatic information is instructive as a cue for guiding attention, whereas the impression of each person is generated according to their own sensory experience and normalized through one's own colour space.
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Affiliation(s)
| | | | | | - Xu Chen
- Department of Design, Kyushu University, Fukuoka 810-8540, Japan
| | - Satohiro Tajima
- Department of Basic Neuroscience, University of Geneva, Geneva 1211, Switzerland
- JST Sakigake/PRESTO, Tokyo 102-0076, Japan
| | - Takeharu Seno
- Department of Design, Kyushu University, Fukuoka 810-8540, Japan
| | - Shoji Kawamura
- Department of Integrated Biosciences, The University of Tokyo, Chiba 277-8562, Japan
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8
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Marques DN, Gomes AE, Linhares JMM, Nascimento SMC. Discrimination of natural colors in anomalous trichromacy and the effects of EnChroma and Vino filters. OPTICS EXPRESS 2023; 31:18075-18087. [PMID: 37381526 DOI: 10.1364/oe.451326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 05/19/2022] [Indexed: 06/30/2023]
Abstract
It is still unclear how well anomalous trichromats discriminate natural colors and whether commercial spectral filters improve performance in these conditions. We show that anomalous trichromats have good color discrimination with colors drawn from natural environments. It is only about 14% poorer, on average, than normal trichromats in our sample of thirteen anomalous trichromats. No measurable effect of the filters on discrimination was found, even after 8 hours of continuous use. Computations of cone and post-receptoral signals show only a modest increase in medium-to-long-wavelength difference signals, which may explain the absent effect of the filters.
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9
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EMERY KARAJ, ISHERWOOD ZOEYJ, WEBSTER MICHAELA. Gaining the system: limits to compensating color deficiencies through post-receptoral gain changes. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2023; 40:A16-A25. [PMID: 37132998 PMCID: PMC10157001 DOI: 10.1364/josaa.480035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/14/2022] [Indexed: 05/04/2023]
Abstract
Color percepts of anomalous trichromats are often more similar to normal trichromats than predicted from their receptor spectral sensitivities, suggesting that post-receptoral mechanisms can compensate for chromatic losses. The basis for these adjustments and the extent to which they could discount the deficiency are poorly understood. We modeled the patterns of compensation that might result from increasing the gains in post-receptoral neurons to offset their weakened inputs. Individual neurons and the population responses jointly encode luminance and chromatic signals. As a result, they cannot independently adjust for a change in the chromatic inputs, predicting only partial recovery of the chromatic responses and increased responses to achromatic contrast. These analyses constrain the potential sites and mechanisms of compensation for a color loss and characterize the utility and limits of neural gain changes for calibrating color vision.
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Affiliation(s)
- KARA J. EMERY
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, Reno NV 89557
- Center for Data Science, New York University, New York NY 10011
| | - ZOEY J. ISHERWOOD
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, Reno NV 89557
| | - MICHAEL A. WEBSTER
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, Reno NV 89557
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10
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Aseyev N. Perception of color in primates: A conceptual color neurons hypothesis. Biosystems 2023; 225:104867. [PMID: 36792004 DOI: 10.1016/j.biosystems.2023.104867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 02/12/2023] [Accepted: 02/12/2023] [Indexed: 02/16/2023]
Abstract
Perception of color by humans and other primates is a complex problem, studied by neurophysiology, psychophysiology, psycholinguistics, and even philosophy. Being mostly trichromats, simian primates have three types of opsin proteins, expressed in cone neurons in the eye, which allow for the sensing of color as the physical wavelength of light. Further, in neural networks of the retina, the coding principle changes from three types of sensor proteins to two opponent channels: activity of one type of neuron encode the evolutionarily ancient blue-yellow axis of color stimuli, and another more recent evolutionary channel, encoding the axis of red-green color stimuli. Both color channels are distinctive in neural organization at all levels from the eye to the neocortex, where it is thought that the perception of color (as philosophical qualia) emerges from the activity of some neuron ensembles. Here, using data from neurophysiology as a starting point, we propose a hypothesis on how the perception of color can be encoded in the activity of certain neurons in the neocortex. These conceptual neurons, herein referred to as 'color neurons', code only the hue of the color of visual stimulus, similar to place cells and number neurons, already described in primate brains. A case study with preliminary, but direct, evidence for existing conceptual color neurons in the human brain was published in 2008. We predict that the upcoming studies in non-human primates will be more extensive and provide a more detailed description of conceptual color neurons.
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Affiliation(s)
- Nikolay Aseyev
- Institute Higher Nervous Activity and Neurophysiology, RAS, Moscow, 117485, Butlerova, 5A, Russian Federation.
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11
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Robinson AE, Bosten JM, MacLeod DIA. Nonlinear cortical encoding of color predicts enhanced McCollough effects in anomalous trichromats. Vision Res 2023; 203:108153. [PMID: 36470153 DOI: 10.1016/j.visres.2022.108153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/24/2022] [Accepted: 11/03/2022] [Indexed: 12/05/2022]
Abstract
Nonlinear encoding of chromatic contrast by the early visual cortex predicts that anomalous trichromats will show a larger McCollough effect than normal trichromats. In Experiment 1 we employed the McCollough effect to probe the cortical representation of saturation in normal trichromats, and used the results to predict enhanced McCollough effects for anomalous trichromats, which we measured in Experiment 2. In Experiment 1 three participants adapted to red and green orthogonal gratings of four different saturations. Using nulling to measure aftereffect strength, we found that halving the saturation of the inducing gratings decreased aftereffect strength only slightly, consistent with a compressive coding of saturation in early visual cortex. In anomalous trichromats, cone contrasts between red and green are greatly decreased from those of normal trichromats, but induced aftereffects are only slightly decreased, because of the non-linearity in the cortical encoding of saturation. To null the aftereffect, however, the retinal color deficiency must be overcome by adding more color to the null than required by normal trichromats. We confirmed this prediction in Experiment 2 where four anomalous trichromats required nulling stimuli approximately four times more saturated than did normal trichromats. We consider two competing models to explain our results: in a 'pigment swap' model anomalous trichromats have an altered photopigment but process color postreceptorally in the same way as normal trichromats; in a 'postreceptoral compensation' model the cortical representation of red-green contrasts is amplified to compensate for reduced cone contrasts. The latter provided a better fit to our data.
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Affiliation(s)
- Alan E Robinson
- UC San Diego Department of Psychology; UC San Diego Department of Cognitive Science
| | - Jenny M Bosten
- UC San Diego Department of Psychology; School of Psychology, University of Sussex, Brighton, UK.
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12
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Abstract
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.
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Affiliation(s)
- John Maule
- The Sussex Colour Group & Baby Lab, School of Psychology, University of Sussex, Falmer, United Kingdom;
| | - Alice E Skelton
- The Sussex Colour Group & Baby Lab, School of Psychology, University of Sussex, Falmer, United Kingdom;
| | - Anna Franklin
- The Sussex Colour Group & Baby Lab, School of Psychology, University of Sussex, Falmer, United Kingdom;
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13
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Bosten JM, Coen-Cagli R, Franklin A, Solomon SG, Webster MA. Calibrating Vision: Concepts and Questions. Vision Res 2022; 201:108131. [PMID: 37139435 PMCID: PMC10151026 DOI: 10.1016/j.visres.2022.108131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The idea that visual coding and perception are shaped by experience and adjust to changes in the environment or the observer is universally recognized as a cornerstone of visual processing, yet the functions and processes mediating these calibrations remain in many ways poorly understood. In this article we review a number of facets and issues surrounding the general notion of calibration, with a focus on plasticity within the encoding and representational stages of visual processing. These include how many types of calibrations there are - and how we decide; how plasticity for encoding is intertwined with other principles of sensory coding; how it is instantiated at the level of the dynamic networks mediating vision; how it varies with development or between individuals; and the factors that may limit the form or degree of the adjustments. Our goal is to give a small glimpse of an enormous and fundamental dimension of vision, and to point to some of the unresolved questions in our understanding of how and why ongoing calibrations are a pervasive and essential element of vision.
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Affiliation(s)
| | - Ruben Coen-Cagli
- Department of Systems Computational Biology, and Dominick P. Purpura Department of Neuroscience, and Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx NY
| | | | - Samuel G Solomon
- Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, UK
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14
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Álvaro L, Linhares JMM, Formankiewicz MA, Waugh SJ. Coloured filters can simulate colour deficiency in normal vision but cannot compensate for congenital colour vision deficiency. Sci Rep 2022; 12:11140. [PMID: 35778454 PMCID: PMC9249763 DOI: 10.1038/s41598-022-13877-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 05/30/2022] [Indexed: 11/28/2022] Open
Abstract
Red-green colour vision deficiency (CVD) affects ~ 4% of Caucasians. Notch filters exist to simulate CVD when worn by colour vision normal (CVN) observers (simulation tools), or to improve colour discrimination when worn by CVD observers (compensation tools). The current study assesses effects of simulation (Variantor) and compensation (EnChroma) filters on performance in a variety of tasks. Experiments were conducted on 20 CVN and 16 CVD participants under no-filter and filter conditions (5 CVN used Variantor; 15 CVN and 16 CVD used EnChroma). Participants were tested on Ishihara and Farnsworth-Munsell 100 hue tests, CVA-UMinho colour discrimination and colour naming tasks and a board-game colour-sorting task. Repeated-measures ANOVAs found Variantor filters to significantly worsen CVN performance, mimicking protanopia. Mixed-model and repeated-measures ANOVAs demonstrate that EnChroma filters do not significantly enhance performance in CVD observers. Key EnChroma results were replicated in 8 CVD children (Ishihara test) and a sub-sample of 6 CVD adults (CVA-UMinho colour discrimination and colour naming tasks) for a smaller stimulus size. Pattern similarity exists across hue for discrimination thresholds and naming errors. Variantor filters are effective at mimicking congenital colour vision defects in CVN observers for all tasks, however EnChroma filters do not significantly compensate for CVD in any.
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Affiliation(s)
- Leticia Álvaro
- Anglia Vision Research, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge, CB1 1PT, UK. .,Dpto. Psicología experimental, Procesos cognitivos y Logopedia, Universidad Complutense de Madrid, 28883, Pozuelo de Alarcón, Spain.
| | - João M M Linhares
- Physics Centre of Minho and Porto Universities (CF-UM-UP), Gualtar Campus, University of Minho, 4710-057, Braga, Portugal
| | - Monika A Formankiewicz
- Anglia Vision Research, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge, CB1 1PT, UK
| | - Sarah J Waugh
- Anglia Vision Research, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge, CB1 1PT, UK.,Centre for Vision Across the Life Span, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
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15
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Abstract
In our tendency to discuss the objective properties of the external world, we may fail to notice that our subjective perceptions of those properties differ between individuals. Variability at all levels of the color vision system creates diversity in color perception, from discrimination to color matching, appearance, and subjective experience, such that each of us lives in a unique perceptual world. In this review, I discuss what is known about individual differences in color perception and its determinants, particularly considering genetically mediated variability in cone photopigments and the paradoxical effects of visual environments in both contributing to and counteracting individual differences. I make the case that, as well as being of interest in their own right and crucial for a complete account of color vision, individual differences can be used as a methodological tool in color science for the insights that they offer about the underlying mechanisms of perception. Expected final online publication date for the Annual Review of Vision Science, Volume 8 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Jenny M Bosten
- School of Psychology, University of Sussex, Brighton, United Kingdom;
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16
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Ilic I, Lee KR, Mizokami Y, Whitehead L, Webster MA. Adapting to an enhanced color gamut - implications for color vision and color deficiencies. OPTICS EXPRESS 2022; 30:20999-21015. [PMID: 36224831 PMCID: PMC9363022 DOI: 10.1364/oe.456067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 05/02/2022] [Accepted: 05/11/2022] [Indexed: 05/28/2023]
Abstract
One strategy for aiding color deficiencies is to use three narrow passbands to filter the light spectrum to increase the saturation of colors. This filtering is analogous to the narrow emission bands used in wide gamut lighting or displays. We examined how perception adapts to the greater color gamut area produced by such devices, testing color-normal observers and simulated environments. Narrowband spectra increased chromatic contrasts but also increased contrast adaptation, partially offsetting the perceived contrast enhancements. Such adaptation adjustments are important for understanding the perceptual consequences of exposure to naturally or artificially enhanced color gamut areas for both color-deficient and color-normal observers.
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Affiliation(s)
- Ivana Ilic
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, USA
| | - Kassandra R. Lee
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, USA
| | - Yoko Mizokami
- Department of Imaging Sciences, Chiba University, USA
| | - Lorne Whitehead
- Department of Physics and Astronomy, University of British Columbia, USA
| | - Michael A. Webster
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, USA
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17
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Nascimento SMC, Foster DH. Information gains from commercial spectral filters in anomalous trichromacy. OPTICS EXPRESS 2022; 30:16883-16895. [PMID: 36221522 DOI: 10.1364/oe.451407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 04/19/2022] [Indexed: 06/16/2023]
Abstract
Red-green color discrimination is compromised in anomalous trichromacy, the most common inherited color vision deficiency. This computational analysis tested whether three commercial optical filters with medium-to-long-wavelength stop bands increased information about colored surfaces. The surfaces were sampled from 50 hyperspectral images of outdoor scenes. At best, potential gains in the effective number of surfaces discriminable solely by color reached 9% in protanomaly and 15% in deuteranomaly, much less than with normal trichromacy. Gains were still less with lower scene illumination and more severe color vision deficiency. Stop-band filters may offer little improvement in objective real-world color discrimination.
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18
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Automatic compensation enhances the orientation perception in chronic astigmatism. Sci Rep 2022; 12:3710. [PMID: 35260694 PMCID: PMC8904485 DOI: 10.1038/s41598-022-07788-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 02/24/2022] [Indexed: 11/10/2022] Open
Abstract
Astigmatism is a prevalent optical problem in which two or more focal points blur the retinal image at a particular meridian. Although many features of astigmatic vision, including orientation perception, are impaired at the retinal image level, the visual system appears to partly restore perceptual impairment after an extended period of astigmatism. However, the mechanism of orientation perception restoration in chronic astigmatism has not yet been clarified. We investigated the notable reduction of perceptual error in chronic astigmatism by comparing the orientation perception of a chronic astigmatism group with the perception of a normal-vision group, in which astigmatism was transiently induced. We found that orientation perception in the chronic group was more accurate than in the normal vision group. Interestingly, the reduction of perceptual errors was automatic; it remained even after the optical refractive errors were fully corrected, and the orientation perception was much more stable across different orientations, despite the uneven noise levels of the retinal images across meridians. We provide here a mechanistic explanation for how the compensation of astigmatic orientation perception occurred, using neural adaptation to the biased distribution of orientations.
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19
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Zhang LQ, Cottaris NP, Brainard DH. An image reconstruction framework for characterizing initial visual encoding. eLife 2022; 11:e71132. [PMID: 35037622 PMCID: PMC8846596 DOI: 10.7554/elife.71132] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 01/14/2022] [Indexed: 11/13/2022] Open
Abstract
We developed an image-computable observer model of the initial visual encoding that operates on natural image input, based on the framework of Bayesian image reconstruction from the excitations of the retinal cone mosaic. Our model extends previous work on ideal observer analysis and evaluation of performance beyond psychophysical discrimination, takes into account the statistical regularities of the visual environment, and provides a unifying framework for answering a wide range of questions regarding the visual front end. Using the error in the reconstructions as a metric, we analyzed variations of the number of different photoreceptor types on human retina as an optimal design problem. In addition, the reconstructions allow both visualization and quantification of information loss due to physiological optics and cone mosaic sampling, and how these vary with eccentricity. Furthermore, in simulations of color deficiencies and interferometric experiments, we found that the reconstructed images provide a reasonable proxy for modeling subjects' percepts. Lastly, we used the reconstruction-based observer for the analysis of psychophysical threshold, and found notable interactions between spatial frequency and chromatic direction in the resulting spatial contrast sensitivity function. Our method is widely applicable to experiments and applications in which the initial visual encoding plays an important role.
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Affiliation(s)
- Ling-Qi Zhang
- Department of Psychology, University of PennsylvaniaPhiladelphiaUnited States
| | - Nicolas P Cottaris
- Department of Psychology, University of PennsylvaniaPhiladelphiaUnited States
| | - David H Brainard
- Department of Psychology, University of PennsylvaniaPhiladelphiaUnited States
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20
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Rabin J, Silva F, Trevino N, Gillentine H, Li L, Inclan L, Anderson G, Lee E, Vo H. Performance enhancement in color deficiency with color-correcting lenses. Eye (Lond) 2022; 36:1502-1503. [PMID: 34999724 DOI: 10.1038/s41433-021-01924-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 11/09/2022] Open
Affiliation(s)
- Jeff Rabin
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA.
| | - Frances Silva
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Natalie Trevino
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Harper Gillentine
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Liqing Li
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Loary Inclan
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Gary Anderson
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Erica Lee
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
| | - Harrison Vo
- University of the Incarnate Word Rosenberg School of Optometry, San Antonio, TX, USA
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21
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Barnett MA, Aguirre GK, Brainard D. A quadratic model captures the human V1 response to variations in chromatic direction and contrast. eLife 2021; 10:65590. [PMID: 34342580 PMCID: PMC8452309 DOI: 10.7554/elife.65590] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 07/27/2021] [Indexed: 11/13/2022] Open
Abstract
An important goal for vision science is to develop quantitative models of the representation of visual signals at post-receptoral sites. To this end, we develop the quadratic color model (QCM) and examine its ability to account for the BOLD fMRI response in human V1 to spatially-uniform, temporal chromatic modulations that systematically vary in chromatic direction and contrast. We find that the QCM explains the same, cross-validated variance as a conventional general linear model, with far fewer free parameters. The QCM generalizes to allow prediction of V1 responses to a large range of modulations. We replicate the results for each subject and find good agreement across both replications and subjects. We find that within the LM cone contrast plane, V1 is most sensitive to L-M contrast modulations and least sensitive to L+M contrast modulations. Within V1, we observe little to no change in chromatic sensitivity as a function of eccentricity.
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Affiliation(s)
- Michael A Barnett
- Department of Psychology, University of Pennsylvania, Philadelphia, United States
| | | | - David Brainard
- Neurology, University of Pennsylvania, Philadelphia, United States
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22
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Boehm AE, Bosten J, MacLeod DIA. Color discrimination in anomalous trichromacy: Experiment and theory. Vision Res 2021; 188:85-95. [PMID: 34293614 DOI: 10.1016/j.visres.2021.05.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 05/28/2021] [Accepted: 05/29/2021] [Indexed: 11/19/2022]
Abstract
In anomalous trichromacy, the color signals available from comparing the activities of the two classes of cone sensitive in the medium and long wavelength parts of the spectrum are much reduced from those available in normal trichromacy, and color discrimination thresholds along the red-green axis are correspondingly elevated. Yet there is evidence that suprathreshold color perception is relatively preserved; this has led to the suggestion that anomalous trichromats post-receptorally amplify their impoverished red-green signals. To test this idea, we measured chromatic discrimination from white and from saturated red and green pedestals. If there is no post-receptoral compensation, the anomalous trichromat's loss of chromatic contrast will apply equally to the pedestal and to the test color. Coupled with a compressively nonlinear neural representation of saturation, this means that a given pedestal contrast will cause a smaller than normal modulation of discrimination sensitivity. We examined cases where chromatic pedestals impair the color discrimination of normal trichromatic observers. As predicted, anomalous observers experienced less impairment than normal trichromats, though they remained less sensitive than normal trichromats. Although the effectiveness of chromatic pedestals in impairing color discrimination was less for anomalous than for normal trichromats, the chromatic pedestals were more effective for anomalous observers than would be expected if the anomalous post-receptoral visual system were the same as in normal trichromacy; the hypothesis of zero compensation can be rejected. This might suggest that the effective contrast of the pedestal is post-receptorally amplified. But on closer analysis, the results do not support candidate simple models involving post-receptoral compensation either.
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Affiliation(s)
- Alexandra E Boehm
- Department of Psychology, University of California, San Diego, CA, USA; Vision Science Graduate Group, University of California, Berkeley, CA, USA; School of Optometry, University of California, Berkeley, CA, USA
| | - Jenny Bosten
- Department of Psychology, University of California, San Diego, CA, USA; School of Psychology, University of Sussex, Brighton, UK
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23
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Abbatecola C, Gerardin P, Beneyton K, Kennedy H, Knoblauch K. The Role of Unimodal Feedback Pathways in Gender Perception During Activation of Voice and Face Areas. Front Syst Neurosci 2021; 15:669256. [PMID: 34122023 PMCID: PMC8194406 DOI: 10.3389/fnsys.2021.669256] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/22/2021] [Indexed: 11/18/2022] Open
Abstract
Cross-modal effects provide a model framework for investigating hierarchical inter-areal processing, particularly, under conditions where unimodal cortical areas receive contextual feedback from other modalities. Here, using complementary behavioral and brain imaging techniques, we investigated the functional networks participating in face and voice processing during gender perception, a high-level feature of voice and face perception. Within the framework of a signal detection decision model, Maximum likelihood conjoint measurement (MLCM) was used to estimate the contributions of the face and voice to gender comparisons between pairs of audio-visual stimuli in which the face and voice were independently modulated. Top–down contributions were varied by instructing participants to make judgments based on the gender of either the face, the voice or both modalities (N = 12 for each task). Estimated face and voice contributions to the judgments of the stimulus pairs were not independent; both contributed to all tasks, but their respective weights varied over a 40-fold range due to top–down influences. Models that best described the modal contributions required the inclusion of two different top–down interactions: (i) an interaction that depended on gender congruence across modalities (i.e., difference between face and voice modalities for each stimulus); (ii) an interaction that depended on the within modalities’ gender magnitude. The significance of these interactions was task dependent. Specifically, gender congruence interaction was significant for the face and voice tasks while the gender magnitude interaction was significant for the face and stimulus tasks. Subsequently, we used the same stimuli and related tasks in a functional magnetic resonance imaging (fMRI) paradigm (N = 12) to explore the neural correlates of these perceptual processes, analyzed with Dynamic Causal Modeling (DCM) and Bayesian Model Selection. Results revealed changes in effective connectivity between the unimodal Fusiform Face Area (FFA) and Temporal Voice Area (TVA) in a fashion that paralleled the face and voice behavioral interactions observed in the psychophysical data. These findings explore the role in perception of multiple unimodal parallel feedback pathways.
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Affiliation(s)
- Clement Abbatecola
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, Bron, France.,Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Peggy Gerardin
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, Bron, France
| | - Kim Beneyton
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, Bron, France
| | - Henry Kennedy
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, Bron, France.,Institute of Neuroscience, State Key Laboratory of Neuroscience, Chinese Academy of Sciences Key Laboratory of Primate Neurobiology, Shanghai, China
| | - Kenneth Knoblauch
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, Bron, France.,National Centre for Optics, Vision and Eye Care, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway
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24
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Vanston JE, Tregillus KEM, Webster MA, Crognale MA. Task-dependent contrast gain in anomalous trichromats. Vision Res 2021; 184:14-22. [PMID: 33773293 DOI: 10.1016/j.visres.2021.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 01/25/2021] [Accepted: 02/04/2021] [Indexed: 12/18/2022]
Abstract
Anomalous trichromacy is a form of color vision deficiency characterized by the presence of three cone types, but with shifted spectral sensitivities for L or M cones, causing a red-green color deficiency. However, long-term adaptation to this impoverished opponent input may allow for a more normal color experience at the suprathreshold level ("compensation"). Recent experimental evidence points to the presence of compensation in some tasks. The current study used threshold detection, suprathreshold contrast matching, and a reaction-time task to compare contrast coding in normal and anomalous observers along the cardinal cone-opponent axes. Compared to color normals, anomals required more L-M contrast, but not S contrast, to detect stimuli and to match an achromatic reference stimulus. Reaction times were measured for several contrast levels along the two cone-opponent axes. Anomals had higher overall reaction times, but their reaction-time versus contrast functions could be matched to those of controls simply by scaling contrast by the detection thresholds. Anomalous participants were impaired relative to controls for L-M stimuli in all three tasks. However, the contrast losses were three times greater for thresholds and reaction times than for suprathreshold matches. These data provide evidence for compensation in anomalous trichromats, but highlight the role that the experimental task plays in revealing it.
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Affiliation(s)
- John E Vanston
- Department of Psychology, University of Nevada, Reno 1664 N Virginia St., Reno, NV 89557, USA; School of Optometry and Vision Science Graduate Group, University of California, Minor Hall, Berkeley, CA 94720, USA.
| | - Katherine E M Tregillus
- Department of Psychology, University of Nevada, Reno 1664 N Virginia St., Reno, NV 89557, USA
| | - Michael A Webster
- Department of Psychology, University of Nevada, Reno 1664 N Virginia St., Reno, NV 89557, USA
| | - Michael A Crognale
- Department of Psychology, University of Nevada, Reno 1664 N Virginia St., Reno, NV 89557, USA
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25
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Emery KJ, Kuppuswamy Parthasarathy M, Joyce DS, Webster MA. Color perception and compensation in color deficiencies assessed with hue scaling. Vision Res 2021; 183:1-15. [PMID: 33636681 DOI: 10.1016/j.visres.2021.01.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/07/2020] [Accepted: 01/14/2021] [Indexed: 12/20/2022]
Abstract
Anomalous trichromats have three classes of cone receptors but with smaller separation in the spectral sensitivities of their longer-wave (L or M) cones compared to normal trichromats. As a result, the differences in the responses of the longer-wave cones are smaller, resulting in a weaker input to opponent mechanisms that compare the LvsM responses. Despite this, previous studies have found that their color percepts are more similar to normal trichromats than the smaller LvsM differences predict, suggesting that post-receptoral processes might amplify their responses to compensate for the weaker opponent inputs. We evaluated the degree and form of compensation using a hue-scaling task, in which the appearance of different hues is described by the perceived proportions of red-green or blue-yellow primary colors. The scaling functions were modeled to estimate the relative salience of the red-green to blue-yellow components. The red-green amplitudes of the 10 anomalous observers were 1.5 times weaker than for a group of 26 normal controls. However, their relative sensitivity at threshold for detecting LvsM chromatic contrast was on average 6 times higher, consistent with a 4-fold gain in the suprathreshold hue-scaling responses. Within-observer variability in the settings was similar for the two groups, suggesting that the suprathreshold gain did not similarly amplify the noise, at least for the dimension of hue. While the compensation was pronounced it was nevertheless partial, and anomalous observers differed systematically from the controls in the shapes of the hue-scaling functions and the corresponding loci of their color categories. Factor analyses further revealed different patterns of individual differences between the groups. We discuss the implications of these results for understanding both the processes of compensation for a color deficiency and the limits of these processes.
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Affiliation(s)
- Kara J Emery
- Graduate Program in Integrative Neuroscience and Department of Psychology, University of Nevada, Reno, Reno, NV 89557, United States
| | - Mohana Kuppuswamy Parthasarathy
- Graduate Program in Integrative Neuroscience and Department of Psychology, University of Nevada, Reno, Reno, NV 89557, United States
| | - Daniel S Joyce
- Graduate Program in Integrative Neuroscience and Department of Psychology, University of Nevada, Reno, Reno, NV 89557, United States
| | - Michael A Webster
- Graduate Program in Integrative Neuroscience and Department of Psychology, University of Nevada, Reno, Reno, NV 89557, United States.
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