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Durand JB, Marchand S, Nasres I, Laeng B, De Castro V. Illusory light drives pupil responses in primates. J Vis 2024; 24:14. [PMID: 39046721 PMCID: PMC11271809 DOI: 10.1167/jov.24.7.14] [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: 02/29/2024] [Accepted: 06/07/2024] [Indexed: 07/25/2024] Open
Abstract
In humans, the eye pupils respond to both physical light sensed by the retina and mental representations of light produced by the brain. Notably, our pupils constrict when a visual stimulus is illusorily perceived brighter, even if retinal illumination is constant. However, it remains unclear whether such perceptual penetrability of pupil responses is an epiphenomenon unique to humans or whether it represents an adaptive mechanism shared with other animals to anticipate variations in retinal illumination between successive eye fixations. To address this issue, we measured the pupil responses of both humans and macaque monkeys exposed to three chromatic versions (cyan, magenta, and yellow) of the Asahi brightness illusion. We found that the stimuli illusorily perceived brighter or darker trigger differential pupil responses that are very similar in macaques and human participants. Additionally, we show that this phenomenon exhibits an analogous cyan bias in both primate species. Beyond evincing the macaque monkey as a relevant model to study the perceptual penetrability of pupil responses, our results suggest that this phenomenon is tuned to ecological conditions because the exposure to a "bright cyan-bluish sky" may be associated with increased risks of dazzle and retinal damages.
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Affiliation(s)
- Jean-Baptiste Durand
- Université de Toulouse, Centre de Recherche Cerveau et Cognition, Toulouse, France
- Centre National de la Recherche Scientifique, Toulouse, France
| | - Sarah Marchand
- Université de Toulouse, Centre de Recherche Cerveau et Cognition, Toulouse, France
- Centre National de la Recherche Scientifique, Toulouse, France
| | - Ilyas Nasres
- Université de Toulouse, Centre de Recherche Cerveau et Cognition, Toulouse, France
- Centre National de la Recherche Scientifique, Toulouse, France
| | - Bruno Laeng
- Department of Psychology, University of Oslo, Oslo, Norway
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - Vanessa De Castro
- Université de Toulouse, Centre de Recherche Cerveau et Cognition, Toulouse, France
- Centre National de la Recherche Scientifique, Toulouse, France
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2
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Godat T, Kohout K, Parkins K, Yang Q, McGregor JE, Merigan WH, Williams DR, Patterson SS. Cone-Opponent Ganglion Cells in the Primate Fovea Tuned to Noncardinal Color Directions. J Neurosci 2024; 44:e1738232024. [PMID: 38548340 PMCID: PMC11063829 DOI: 10.1523/jneurosci.1738-23.2024] [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: 09/14/2023] [Revised: 02/20/2024] [Accepted: 03/15/2024] [Indexed: 04/09/2024] Open
Abstract
A long-standing question in vision science is how the three cone photoreceptor types-long (L), medium (M), and short (S) wavelength sensitive-combine to generate our perception of color. Hue perception can be described along two opponent axes: red-green and blue-yellow. Psychophysical measurements of color appearance indicate that the cone inputs to the red-green and blue-yellow opponent axes are M vs. L + S and L vs. M + S, respectively. However, the "cardinal directions of color space" revealed by psychophysical measurements of color detection thresholds following adaptation are L vs. M and S vs. L + M. These cardinal directions match the most common cone-opponent retinal ganglion cells (RGCs) in the primate retina. Accordingly, the cone opponency necessary for color appearance is thought to be established in the cortex. While neurons with the appropriate M vs. L + S and L vs. M + S opponency have been reported in the retina and lateral geniculate nucleus, their existence continues to be debated. Resolving this long-standing debate is necessary because a complete account of the cone opponency in the retinal output is critical for understanding how downstream neural circuits process color. Here, we performed adaptive optics calcium imaging to noninvasively measure foveal RGC light responses in the living Macaca fascicularis eye. We confirm the presence of L vs. M + S and M vs. L + S neurons with noncardinal cone opponency and demonstrate that cone-opponent signals in the retinal output are more diverse than classically thought.
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Affiliation(s)
- Tyler Godat
- Center for Visual Science, University of Rochester, Rochester, New York 14607
- Institute of Optics, University of Rochester, Rochester, New York 14611
| | - Kendall Kohout
- Center for Visual Science, University of Rochester, Rochester, New York 14607
| | - Keith Parkins
- Center for Visual Science, University of Rochester, Rochester, New York 14607
| | - Qiang Yang
- Center for Visual Science, University of Rochester, Rochester, New York 14607
| | - Juliette E McGregor
- Center for Visual Science, University of Rochester, Rochester, New York 14607
- Flaum Eye Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - William H Merigan
- Center for Visual Science, University of Rochester, Rochester, New York 14607
- Flaum Eye Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - David R Williams
- Center for Visual Science, University of Rochester, Rochester, New York 14607
- Institute of Optics, University of Rochester, Rochester, New York 14611
- Flaum Eye Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Sara S Patterson
- Center for Visual Science, University of Rochester, Rochester, New York 14607
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3
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Vani V, Ojha P, Gadhvi MA, Dixit A. Attentional Correlates of Colored Lights: Considerations for Cognitive Testing. Neuroscience 2024; 543:83-89. [PMID: 38403240 DOI: 10.1016/j.neuroscience.2024.02.010] [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: 12/30/2023] [Revised: 02/05/2024] [Accepted: 02/12/2024] [Indexed: 02/27/2024]
Abstract
Attention, an important index of cognitive function, can be affected amidst colored lights. This work investigated the effects of colored lights on the performance in attention task. Participants (N = 42) performed in one, two, and three letter cancellation task (LCT) during four lighting conditions. The order of LCT and the colored light sessions were randomized. The performance in LCT was evaluated through % accuracy, % omission, and % error. A repeated measures ANOVA showed a statistically significant difference in % accuracy in one LCT (F(2.46, 100.8) = 24.45, p < 0.001), two LCT (F(2.57, 105.4) = 20.53, p < 0.001), and three LCT (F(2.66, 109.22) = 17.96, p < 0.001) among the four colored lights. In addition, % omission revealed a statistically significant difference in one LCT (F(2.46, 100.8) = 24.43, p < 0.001), two LCT (F(2.57, 105.4) = 20.57, p < 0.001), and three LCT (F(2.66, 109.16) = 18.21, p < 0.001) among the four lights. There was no statistically significant difference in % error in one LCT (F(2.05, 84.1) = 1.23, p = 0.3), two LCT (F(2.66, 109.06) = 0.62, p = 0.971), three LCT (F(2.62, 107.53) = 0.97, p = 0.4) among the four lighting conditions. Colored lights affect attention-related cognitive processing. The attentional correlates of white and red lights are more compared to green, and blue lights. Lighting condition should be an important consideration for cognitive testing, for designing workspaces, educational settings, and other environments where attention plays a crucial role.
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Affiliation(s)
- Vakode Vani
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Pooja Ojha
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India.
| | - Mahesh Arjundan Gadhvi
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Abhinav Dixit
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
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4
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van Leeuwen JEP, McDougall A, Mylonas D, Suárez-González A, Crutch SJ, Warren JD. Pupil responses to colorfulness are selectively reduced in healthy older adults. Sci Rep 2023; 13:22139. [PMID: 38092848 PMCID: PMC10719259 DOI: 10.1038/s41598-023-48513-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 11/27/2023] [Indexed: 12/17/2023] Open
Abstract
The alignment between visual pathway signaling and pupil dynamics offers a promising non-invasive method to further illuminate the mechanisms of human color perception. However, only limited research has been done in this area and the effects of healthy aging on pupil responses to the different color components have not been studied yet. Here we aim to address this by modelling the effects of color lightness and chroma (colorfulness) on pupil responses in young and older adults, in a closely controlled passive viewing experiment with 26 broad-spectrum digital color fields. We show that pupil responses to color lightness and chroma are independent from each other in both young and older adults. Pupil responses to color lightness levels are unaffected by healthy aging, when correcting for smaller baseline pupil sizes in older adults. Older adults exhibit weaker pupil responses to chroma increases, predominantly along the Green-Magenta axis, while relatively sparing the Blue-Yellow axis. Our findings complement behavioral studies in providing physiological evidence that colors fade with age, with implications for color-based applications and interventions both in healthy aging and later-life neurodegenerative disorders.
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Affiliation(s)
- Janneke E P van Leeuwen
- Dementia Research Centre, UCL Queen Square Institute of Neurology, University College London, 8-11 Queen Square, London, WC1N 3AR, UK.
- The Thinking Eye, ACAVA Limehouse Arts Foundation, London, UK.
| | - Amy McDougall
- Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, UK
| | - Dimitris Mylonas
- Faculty of Philosophy, Northeastern University London, London, UK
| | - Aida Suárez-González
- Dementia Research Centre, UCL Queen Square Institute of Neurology, University College London, 8-11 Queen Square, London, WC1N 3AR, UK
| | - Sebastian J Crutch
- Dementia Research Centre, UCL Queen Square Institute of Neurology, University College London, 8-11 Queen Square, London, WC1N 3AR, UK
| | - Jason D Warren
- Dementia Research Centre, UCL Queen Square Institute of Neurology, University College London, 8-11 Queen Square, London, WC1N 3AR, UK.
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5
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Conway BR, Malik-Moraleda S, Gibson E. Color appearance and the end of Hering's Opponent-Colors Theory. Trends Cogn Sci 2023; 27:791-804. [PMID: 37394292 PMCID: PMC10527909 DOI: 10.1016/j.tics.2023.06.003] [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: 06/14/2022] [Revised: 06/02/2023] [Accepted: 06/08/2023] [Indexed: 07/04/2023]
Abstract
Hering's Opponent-Colors Theory has been central to understanding color appearance for 150 years. It aims to explain the phenomenology of colors with two linked propositions. First, a psychological hypothesis stipulates that any color is described necessarily and sufficiently by the extent to which it appears reddish-versus-greenish, bluish-versus-yellowish, and blackish-versus-whitish. Second, a physiological hypothesis stipulates that these perceptual mechanisms are encoded by three innate brain mechanisms. We review the evidence and conclude that neither side of the linking proposition is accurate: the theory is wrong. We sketch out an alternative, Utility-Based Coding, by which the known retinal cone-opponent mechanisms represent optimal encoding of spectral information given competing selective pressure to extract high-acuity spatial information; and phenomenological color categories represent an adaptive, efficient, output of the brain governed by behavioral demands.
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Affiliation(s)
- Bevil R Conway
- Laboratory of Sensorimotor Research, National Eye Institute and National Institute of Mental Health, Bethesda, MD 20892, USA.
| | - Saima Malik-Moraleda
- Department of Brain and Cognitive Sciences, M.I.T., Cambridge, MA 02139, USA; Program in Speech and Hearing Bioscience and Technology, Harvard University, Cambridge, MA 02114, USA
| | - Edward Gibson
- Department of Brain and Cognitive Sciences, M.I.T., Cambridge, MA 02139, USA
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6
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Munds RA, Cooper EB, Janiak MC, Lam LG, DeCasien AR, Bauman Surratt S, Montague MJ, Martinez MI, Research Unit CB, Kawamura S, Higham JP, Melin AD. Variation and heritability of retinal cone ratios in a free-ranging population of rhesus macaques. Evolution 2022; 76:1776-1789. [PMID: 35790204 PMCID: PMC9544366 DOI: 10.1111/evo.14552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/03/2022] [Accepted: 05/12/2022] [Indexed: 01/22/2023]
Abstract
A defining feature of catarrhine primates is uniform trichromacy-the ability to distinguish red (long; L), green (medium; M), and blue (short; S) wavelengths of light. Although the tuning of photoreceptors is conserved, the ratio of L:M cones in the retina is variable within and between species, with human cone ratios differing from other catarrhines. Yet, the sources and structure of variation in cone ratios are poorly understood, precluding a broader understanding of color vision variability. Here, we report a large-scale study of a pedigreed population of rhesus macaques (Macaca mulatta). We collected foveal RNA and analyzed opsin gene expression using cDNA and estimated additive genetic variance of cone ratios. The average L:M ratio and standard error was 1.03:1 ± 0.02. There was no age effect, and genetic contribution to variation was negligible. We found marginal sex effects with females having larger ratios than males. S cone ratios (0.143:1 ± 0.002) had significant genetic variance with a heritability estimate of 43% but did not differ between sexes or age groups. Our results contextualize the derived human condition of L-cone dominance and provide new information about the heritability of cone ratios and variation in primate color vision.
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Affiliation(s)
- Rachel A. Munds
- Department of Anthropology and ArchaeologyUniversity of CalgaryCalgaryABT2N 1N4Canada
| | - Eve B. Cooper
- Department of AnthropologyNew York UniversityNew YorkNew York10003,New York Consortium in Evolutionary PrimatologyNew YorkNew York10460
| | - Mareike C. Janiak
- Department of Anthropology and ArchaeologyUniversity of CalgaryCalgaryABT2N 1N4Canada,Department of AnthropologyNew York UniversityNew YorkNew York10003,School of Science, Engineering and EnvironmentUniversity of SalfordSalfordM5 4NTUnited Kingdom
| | - Linh Gia Lam
- Department of Anthropology and ArchaeologyUniversity of CalgaryCalgaryABT2N 1N4Canada
| | - Alex R. DeCasien
- Department of AnthropologyNew York UniversityNew YorkNew York10003,New York Consortium in Evolutionary PrimatologyNew YorkNew York10460,Section on Developmental NeurogenomicsNational Institute of Mental HealthBethesdaMaryland20892
| | | | - Michael J. Montague
- Department of NeuroscienceUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Melween I. Martinez
- Caribbean Primate Research CenterUniversity of Puerto RicoSan JuanPuerto Rico00936
| | | | - Shoji Kawamura
- Department of Integrated BiosciencesUniversity of TokyoKashiwa277‐8562Japan
| | - James P. Higham
- Department of AnthropologyNew York UniversityNew YorkNew York10003,New York Consortium in Evolutionary PrimatologyNew YorkNew York10460
| | - Amanda D. Melin
- Department of Anthropology and ArchaeologyUniversity of CalgaryCalgaryABT2N 1N4Canada,Department of Medical GeneticsUniversity of CalgaryCalgaryABT2N 1N4Canada,Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryABT2N 1N4Canada
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7
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Westerberg JA, Sigworth EA, Schall JD, Maier A. Pop-out search instigates beta-gated feature selectivity enhancement across V4 layers. Proc Natl Acad Sci U S A 2021; 118:e2103702118. [PMID: 34893538 PMCID: PMC8685673 DOI: 10.1073/pnas.2103702118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2021] [Indexed: 11/18/2022] Open
Abstract
Visual search is a workhorse for investigating how attention interacts with processing of sensory information. Attentional selection has been linked to altered cortical sensory responses and feature preferences (i.e., tuning). However, attentional modulation of feature selectivity during search is largely unexplored. Here we map the spatiotemporal profile of feature selectivity during singleton search. Monkeys performed a search where a pop-out feature determined the target of attention. We recorded laminar neural responses from visual area V4. We first identified "feature columns" which showed preference for individual colors. In the unattended condition, feature columns were significantly more selective in superficial relative to middle and deep layers. Attending a stimulus increased selectivity in all layers but not equally. Feature selectivity increased most in the deep layers, leading to higher selectivity in extragranular layers as compared to the middle layer. This attention-induced enhancement was rhythmically gated in phase with the beta-band local field potential. Beta power dominated both extragranular laminar compartments, but current source density analysis pointed to an origin in superficial layers, specifically. While beta-band power was present regardless of attentional state, feature selectivity was only gated by beta in the attended condition. Neither the beta oscillation nor its gating of feature selectivity varied with microsaccade production. Importantly, beta modulation of neural activity predicted response times, suggesting a direct link between attentional gating and behavioral output. Together, these findings suggest beta-range synaptic activation in V4's superficial layers rhythmically gates attentional enhancement of feature tuning in a way that affects the speed of attentional selection.
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Affiliation(s)
- Jacob A Westerberg
- Department of Psychology, Vanderbilt Brain Institute, Vanderbilt Vision Research Center, Vanderbilt University, Nashville, TN 37240;
| | | | - Jeffrey D Schall
- Centre for Vision Research, Vision: Science to Applications Program, Department of Biology and Department of Psychology, York University, Toronto, ON M3J 1P3, Canada
| | - Alexander Maier
- Department of Psychology, Vanderbilt Brain Institute, Vanderbilt Vision Research Center, Vanderbilt University, Nashville, TN 37240
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8
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Ghasemian S, Vardanjani MM, Sheibani V, Mansouri FA. Color-hierarchies in executive control of monkeys' behavior. Am J Primatol 2021; 83:e23231. [PMID: 33400335 DOI: 10.1002/ajp.23231] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 12/22/2020] [Accepted: 12/22/2020] [Indexed: 12/22/2022]
Abstract
Processing advantages for particular colors (color-hierarchies) influence emotional regulation and cognitive functions in humans and manifest as an advantage of the red color, compared with the green color, in triggering response inhibition but not in response execution. It remains unknown how such color-hierarchies emerge in human cognition and whether they are the unique properties of human brain with advanced trichromatic vision. Dominant models propose that color-hierarchies are formed as experience-dependent learning that associates various colors with different human-made conventions and concepts (e.g., traffic lights). We hypothesized that if color-hierarchies modulate cognitive functions in trichromatic nonhuman primates, it would indicate a preserved neurobiological basis for such color-hierarchies. We trained six macaque monkeys to perform cognitive tasks that required behavioral control based on colored cues. Color-hierarchies significantly influenced monkeys' behavior and appeared as an advantage of the red color, compared to the green, in triggering response inhibition but not response execution. For all monkeys, the order of color-hierarchies, in response inhibition and also execution, was similar to that in humans. In addition, the cognitive effects of color-hierarchies were not limited to the trial in which the colored cues were encountered but also persisted in the following trials in which there was no colored cue on the visual scene. These findings suggest that color-hierarchies are not resulting from association of colors with human-made conventions and that simple processing advantage in retina or early visual pathways does not explain the cognitive effects of color-hierarchies. The discovery of color-hierarchies in cognitive repertoire of monkeys indicates that although the evolution of humans and monkeys diverged in about 25 million years ago, the color-hierarchies are evolutionary preserved, with the same order, in trichromatic primates and exert overarching effects on the executive control of behavior.
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Affiliation(s)
- Sadegh Ghasemian
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.,Cognitive Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Marzieh M Vardanjani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.,Cognitive Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Vahid Sheibani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.,Cognitive Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Farshad A Mansouri
- ARC Centre of Excellence for Integrative Brain Function, Monash University, Clayton, Victoria, Australia
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9
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Abstract
Color is a fundamental aspect of normal visual experience. This chapter provides an overview of the role of color in human behavior, a survey of current knowledge regarding the genetic, retinal, and neural mechanisms that enable color vision, and a review of inherited and acquired defects of color vision including a discussion of diagnostic tests.
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Affiliation(s)
- Joseph Carroll
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, United States.
| | - Bevil R Conway
- Laboratory of Sensorimotor Research, National Eye Institute, National Institute of Mental Health, Bethesda, MD, United States.
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10
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Hardman A, Töllner T, Martinovic J. Neural differences between chromatic- and luminance-driven attentional salience in visual search. J Vis 2020; 20:5. [PMID: 32196068 PMCID: PMC7408945 DOI: 10.1167/jovi.20.3.5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 11/28/2019] [Indexed: 12/02/2022] Open
Abstract
Previous electroencephalographic research on attentional salience did not fully capture the complexities of low-level vision, which relies on both cone-opponent chromatic and cone-additive luminance mechanisms. We systematically varied color and luminance contrast using a visual search task for a higher contrast target to assess the degree to which the salience-computing attentional mechanisms are constrained by low-level visual inputs. In our first experiment, stimuli were defined by contrast that isolated chromatic or luminance mechanisms. In our second experiment, targets were defined by contrasts that isolated or combined achromatic and chromatic mechanisms. In both experiments, event-related potential waveforms contralateral and ipsilateral to the target were qualitatively different for chromatic- compared to luminance-defined stimuli. The same was true of the difference waves computed from these waveforms, with isoluminant stimuli eliciting a mid-latency posterior contralateral negativity (PCN) component and achromatic stimuli eliciting a complex of multiple components, including an early posterior contralateral positivity followed by a late-latency PCN. Combining color with luminance resulted in waveform and difference wave patterns equivalent to those of achromatic stimuli. When large levels of chromaticity contrast were added to targets with small levels of luminance contrast, PCN latency was speeded. In conclusion, the mechanisms underlying attentional salience are constrained by the low-level inputs they receive. Furthermore, speeded PCN latencies for stimuli that combine color and luminance signals compared to stimuli that contain luminance alone demonstrate that color and luminance channels are integrated during pre-attentive visual processing, before top-down allocation of attention is triggered.
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Affiliation(s)
- Amanda Hardman
- School of Psychology, University of Aberdeen, Aberdeen, UK
| | - Thomas Töllner
- Department of Experimental Psychology, Ludwig-Maximilians-University Munich, Munich, Germany
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11
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Communication efficiency of color naming across languages provides a new framework for the evolution of color terms. Cognition 2019; 195:104086. [PMID: 31731116 DOI: 10.1016/j.cognition.2019.104086] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 02/06/2023]
Abstract
Languages vary in their number of color terms. A widely accepted theory proposes that languages evolve, acquiring color terms in a stereotyped sequence. This theory, by Berlin and Kay (BK), is supported by analyzing best exemplars ("focal colors") of basic color terms in the World Color Survey (WCS) of 110 languages. But the instructions of the WCS were complex and the color chips confounded hue and saturation, which likely impacted focal-color selection. In addition, it is now known that even so-called early-stage languages nonetheless have a complete representation of color distributed across the population. These facts undermine the BK theory. Here we revisit the evolution of color terms using original color-naming data obtained with simple instructions in Tsimane', an Amazonian culture that has limited contact with industrialized society. We also collected data in Bolivian-Spanish speakers and English speakers. We discovered that information theory analysis of color-naming data was not influenced by color-chip saturation, which motivated a new analysis of the WCS data. Embedded within a universal pattern in which warm colors (reds, oranges) are always communicated more efficiently than cool colors (blues, greens), as languages increase in overall communicative efficiency about color, some colors undergo greater increases in communication efficiency compared to others. Communication efficiency increases first for yellow, then brown, then purple. The present analyses and results provide a new framework for understanding the evolution of color terms: what varies among cultures is not whether colors are seen differently, but the extent to which color is useful.
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12
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Sandhaeger F, von Nicolai C, Miller EK, Siegel M. Monkey EEG links neuronal color and motion information across species and scales. eLife 2019; 8:e45645. [PMID: 31287792 PMCID: PMC6615858 DOI: 10.7554/elife.45645] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 06/15/2019] [Indexed: 11/26/2022] Open
Abstract
It remains challenging to relate EEG and MEG to underlying circuit processes and comparable experiments on both spatial scales are rare. To close this gap between invasive and non-invasive electrophysiology we developed and recorded human-comparable EEG in macaque monkeys during visual stimulation with colored dynamic random dot patterns. Furthermore, we performed simultaneous microelectrode recordings from 6 areas of macaque cortex and human MEG. Motion direction and color information were accessible in all signals. Tuning of the non-invasive signals was similar to V4 and IT, but not to dorsal and frontal areas. Thus, MEG and EEG were dominated by early visual and ventral stream sources. Source level analysis revealed corresponding information and latency gradients across cortex. We show how information-based methods and monkey EEG can identify analogous properties of visual processing in signals spanning spatial scales from single units to MEG - a valuable framework for relating human and animal studies.
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Affiliation(s)
- Florian Sandhaeger
- Centre for Integrative NeuroscienceUniversity of TübingenTübingenGermany
- Hertie Institute for Clinical Brain ResearchUniversity of TübingenTübingenGermany
- MEG CenterUniversity of TübingenTübingenGermany
- IMPRS for Cognitive and Systems NeuroscienceUniversity of TübingenTübingenGermany
| | - Constantin von Nicolai
- Centre for Integrative NeuroscienceUniversity of TübingenTübingenGermany
- Hertie Institute for Clinical Brain ResearchUniversity of TübingenTübingenGermany
- MEG CenterUniversity of TübingenTübingenGermany
| | - Earl K Miller
- The Picower Institute for Learning and Memory and Department of Brain and Cognitive SciencesMassachusetts Institute of TechnologyCambridgeUnited States
| | - Markus Siegel
- Centre for Integrative NeuroscienceUniversity of TübingenTübingenGermany
- Hertie Institute for Clinical Brain ResearchUniversity of TübingenTübingenGermany
- MEG CenterUniversity of TübingenTübingenGermany
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13
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Gelfand EC, Horwitz GD. Model of parafoveal chromatic and luminance temporal contrast sensitivity of humans and monkeys. J Vis 2018; 18:1. [PMID: 30383213 PMCID: PMC6690402 DOI: 10.1167/18.12.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 08/24/2018] [Indexed: 11/24/2022] Open
Abstract
Rhesus monkeys are a valuable model for studies of primate visual contrast sensitivity. Their visual systems are similar to that of humans, and they can be trained to perform detection tasks at threshold during neurophysiological recording. However, the stimulus dependence of rhesus monkey contrast sensitivity has not been well characterized. Temporal frequency, color, and retinal eccentricity affect the contrast sensitivity of humans in reasonably well-understood ways. To ask whether these factors affect monkey sensitivity similarly, we measured detection thresholds of two monkeys using a two-alternative, forced-choice task and compared them to thresholds of two human subjects who performed the same task. Stimuli were drifting Gabor patterns that varied in temporal frequency (1-60 Hz), L- and M-cone modulation ratio, and retinal eccentricity (2°-14° from the fovea). Thresholds were fit by a model that assumed a pair of linear detection mechanisms: a luminance contrast detector and a red-green contrast detector. Analysis of model fits indicated that the sensitivity of these mechanisms varied across the visual field, but their temporal and spectral tuning did not. Human and monkey temporal contrast sensitivity was similar across the conditions tested, but monkeys were twofold less sensitive to low-frequency, luminance modulations.
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Affiliation(s)
- Emily C Gelfand
- Department of Physiology & Biophysics, Washington National Primate Research Center, University of Washington, Seattle, WA, USA
| | - Gregory D Horwitz
- Department of Physiology & Biophysics, Washington National Primate Research Center, University of Washington, Seattle, WA, USA
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14
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Abstract
Inferior temporal cortex (IT) is a key part of the ventral visual pathway implicated in object, face, and scene perception. But how does IT work? Here, I describe an organizational scheme that marries form and function and provides a framework for future research. The scheme consists of a series of stages arranged along the posterior-anterior axis of IT, defined by anatomical connections and functional responses. Each stage comprises a complement of subregions that have a systematic spatial relationship. The organization of each stage is governed by an eccentricity template, and corresponding eccentricity representations across stages are interconnected. Foveal representations take on a role in high-acuity object vision (including face recognition); intermediate representations compute other aspects of object vision such as behavioral valence (using color and surface cues); and peripheral representations encode information about scenes. This multistage, parallel-processing model invokes an innately determined organization refined by visual experience that is consistent with principles of cortical development. The model is also consistent with principles of evolution, which suggest that visual cortex expanded through replication of retinotopic areas. Finally, the model predicts that the most extensively studied network within IT-the face patches-is not unique but rather one manifestation of a canonical set of operations that reveal general principles of how IT works.
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Affiliation(s)
- Bevil R Conway
- Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland 28092, USA; .,National Institutes of Mental Health, National Institute of Neurological Disease and Stroke, National Institutes of Health, Bethesda, Maryland 28092, USA
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15
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Pitzalis S, Strappini F, Bultrini A, Di Russo F. Detailed spatiotemporal brain mapping of chromatic vision combining high-resolution VEP with fMRI and retinotopy. Hum Brain Mapp 2018. [PMID: 29536594 DOI: 10.1002/hbm.24046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Neuroimaging studies have identified so far, several color-sensitive visual areas in the human brain, and the temporal dynamics of these activities have been separately investigated using the visual-evoked potentials (VEPs). In the present study, we combined electrophysiological and neuroimaging methods to determine a detailed spatiotemporal profile of chromatic VEP and to localize its neural generators. The accuracy of the present co-registration study was obtained by combining standard fMRI data with retinotopic and motion mapping data at the individual level. We found a sequence of occipito activities more complex than that typically reported for chromatic VEPs, including feed-forward and reentrant feedback. Results showed that chromatic human perception arises by the combined activity of at the least five parieto-occipital areas including V1, LOC, V8/VO, and the motion-sensitive dorsal region MT+. However, the contribution of V1 and V8/VO seems dominant because the re-entrant activity in these areas was present more than once (twice in V8/VO and thrice in V1). This feedforward and feedback chromatic processing appears delayed compared with the luminance processing. Associating VEPs and neuroimaging measures, we showed for the first time a complex spatiotemporal pattern of activity, confirming that chromatic stimuli produce intricate interactions of many different brain dorsal and ventral areas.
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Affiliation(s)
- Sabrina Pitzalis
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico,", Rome, Italy.,Santa Lucia Foundation, IRCCS, Rome, Italy
| | | | - Alessandro Bultrini
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico,", Rome, Italy
| | - Francesco Di Russo
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico,", Rome, Italy.,Santa Lucia Foundation, IRCCS, Rome, Italy
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16
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Denman DJ, Luviano JA, Ollerenshaw DR, Cross S, Williams D, Buice MA, Olsen SR, Reid RC. Mouse color and wavelength-specific luminance contrast sensitivity are non-uniform across visual space. eLife 2018; 7:e31209. [PMID: 29319502 PMCID: PMC5762155 DOI: 10.7554/elife.31209] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Accepted: 12/13/2017] [Indexed: 01/10/2023] Open
Abstract
Mammalian visual behaviors, as well as responses in the neural systems underlying these behaviors, are driven by luminance and color contrast. With constantly improving tools for measuring activity in cell-type-specific populations in the mouse during visual behavior, it is important to define the extent of luminance and color information that is behaviorally accessible to the mouse. A non-uniform distribution of cone opsins in the mouse retina potentially complicates both luminance and color sensitivity; opposing gradients of short (UV-shifted) and middle (blue/green) cone opsins suggest that color discrimination and wavelength-specific luminance contrast sensitivity may differ with retinotopic location. Here we ask how well mice can discriminate color and wavelength-specific luminance changes across visuotopic space. We found that mice were able to discriminate color and were able to do so more broadly across visuotopic space than expected from the cone-opsin distribution. We also found wavelength-band-specific differences in luminance sensitivity.
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Affiliation(s)
| | | | | | - Sissy Cross
- Allen Institute for Brain ScienceSeattleUnited States
| | | | | | - Shawn R Olsen
- Allen Institute for Brain ScienceSeattleUnited States
| | - R Clay Reid
- Allen Institute for Brain ScienceSeattleUnited States
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17
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Jacobs GH. Photopigments and the dimensionality of animal color vision. Neurosci Biobehav Rev 2017; 86:108-130. [PMID: 29224775 DOI: 10.1016/j.neubiorev.2017.12.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/04/2017] [Accepted: 12/05/2017] [Indexed: 12/31/2022]
Abstract
Early color-matching studies established that normal human color vision is trichromatic. Subsequent research revealed a causal link between trichromacy and the presence in the retina of three classes of cone photopigments. Over the years, measurements of the photopigment complements of other species have expanded greatly and these are frequently used to predict the dimensionality of an animal's color vision. This review provides an account of how the linkage between the number of active photopigments and the dimensions of human color vision developed, summarizes the various mechanisms that can impact photopigment spectra and number, and provides an across-species survey to examine cases where the photopigment link to the dimensionality of color vision has been claimed. The literature reveals numerous instances where the human model fails to account for the ways in which the visual systems of other animals exploit information obtained from the presence of multiple photopigments in support of their behavior.
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Affiliation(s)
- Gerald H Jacobs
- Department of Psychological and Brain Science, University of California, Santa Barbara, CA 93106, USA.
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18
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Gabree SH, Shepard TG, Eskew RT. Asymmetric high-contrast masking in S cone increment and decrement pathways. Vision Res 2017; 151:61-68. [PMID: 29106967 DOI: 10.1016/j.visres.2017.06.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/19/2017] [Accepted: 06/21/2017] [Indexed: 11/15/2022]
Abstract
Physiological, anatomical, and psychophysical evidence points to important differences between visual processing of short-wave cone increments and decrement (S+ and S-) stimuli. The present study uses the pedestal discrimination paradigm to investigate potential differences, using S+ and S- tests presented on (L)ong-wave, (M)edium-wave, S, L+M, L-M, and achromatic pedestals, of both contrast polarities. Results show that high contrast 'purplish' (S+ or -(L+M)) pedestals produce substantially more masking of both S+ and S- tests than 'yellowish' (S- or +(L+M)) pedestals do. The other pedestals produce no masking. These findings suggest greater nonlinearity - either a static nonlinearity or contrast gain control - in the mechanisms responsible for the 'purplish' polarity, likely the S ON pathway.
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Affiliation(s)
- Scott H Gabree
- Department of Psychology, 125-NI, Northeastern University, Boston, MA 02115, USA
| | - Timothy G Shepard
- Department of Psychology, 125-NI, Northeastern University, Boston, MA 02115, USA.
| | - Rhea T Eskew
- Department of Psychology, 125-NI, Northeastern University, Boston, MA 02115, USA.
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19
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Representation of Perceptual Color Space in Macaque Posterior Inferior Temporal Cortex (the V4 Complex). eNeuro 2016; 3:eN-NWR-0039-16. [PMID: 27595132 PMCID: PMC5002982 DOI: 10.1523/eneuro.0039-16.2016] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 07/19/2016] [Accepted: 08/04/2016] [Indexed: 12/04/2022] Open
Abstract
The lateral geniculate nucleus is thought to represent color using two populations of cone-opponent neurons [L vs M; S vs (L + M)], which establish the cardinal directions in color space (reddish vs cyan; lavender vs lime). How is this representation transformed to bring about color perception? Prior work implicates populations of glob cells in posterior inferior temporal cortex (PIT; the V4 complex), but the correspondence between the neural representation of color in PIT/V4 complex and the organization of perceptual color space is unclear. We compared color-tuning data for populations of glob cells and interglob cells to predictions obtained using models that varied in the color-tuning narrowness of the cells, and the color preference distribution across the populations. Glob cells were best accounted for by simulated neurons that have nonlinear (narrow) tuning and, as a population, represent a color space designed to be perceptually uniform (CIELUV). Multidimensional scaling and representational similarity analyses showed that the color space representations in both glob and interglob populations were correlated with the organization of CIELUV space, but glob cells showed a stronger correlation. Hue could be classified invariant to luminance with high accuracy given glob responses and above-chance accuracy given interglob responses. Luminance could be read out invariant to changes in hue in both populations, but interglob cells tended to prefer stimuli having luminance contrast, regardless of hue, whereas glob cells typically retained hue tuning as luminance contrast was modulated. The combined luminance/hue sensitivity of glob cells is predicted for neurons that can distinguish two colors of the same hue at different luminance levels (orange/brown).
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Color-Biased Regions of the Ventral Visual Pathway Lie between Face- and Place-Selective Regions in Humans, as in Macaques. J Neurosci 2016; 36:1682-97. [PMID: 26843649 DOI: 10.1523/jneurosci.3164-15.2016] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED The existence of color-processing regions in the human ventral visual pathway (VVP) has long been known from patient and imaging studies, but their location in the cortex relative to other regions, their selectivity for color compared with other properties (shape and object category), and their relationship to color-processing regions found in nonhuman primates remain unclear. We addressed these questions by scanning 13 subjects with fMRI while they viewed two versions of movie clips (colored, achromatic) of five different object classes (faces, scenes, bodies, objects, scrambled objects). We identified regions in each subject that were selective for color, faces, places, and object shape, and measured responses within these regions to the 10 conditions in independently acquired data. We report two key findings. First, the three previously reported color-biased regions (located within a band running posterior-anterior along the VVP, present in most of our subjects) were sandwiched between face-selective cortex and place-selective cortex, forming parallel bands of face, color, and place selectivity that tracked the fusiform gyrus/collateral sulcus. Second, the posterior color-biased regions showed little or no selectivity for object shape or for particular stimulus categories and showed no interaction of color preference with stimulus category, suggesting that they code color independently of shape or stimulus category; moreover, the shape-biased lateral occipital region showed no significant color bias. These observations mirror results in macaque inferior temporal cortex (Lafer-Sousa and Conway, 2013), and taken together, these results suggest a homology in which the entire tripartite face/color/place system of primates migrated onto the ventral surface in humans over the course of evolution. SIGNIFICANCE STATEMENT Here we report that color-biased cortex is sandwiched between face-selective and place-selective cortex on the bottom surface of the brain in humans. This face/color/place organization mirrors that seen on the lateral surface of the temporal lobe in macaques, suggesting that the entire tripartite system is homologous between species. This result validates the use of macaques as a model for human vision, making possible more powerful investigations into the connectivity, precise neural codes, and development of this part of the brain. In addition, we find substantial segregation of color from shape selectivity in posterior regions, as observed in macaques, indicating a considerable dissociation of the processing of shape and color in both species.
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21
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Hass CA, Angueyra JM, Lindbloom-Brown Z, Rieke F, Horwitz GD. Chromatic detection from cone photoreceptors to V1 neurons to behavior in rhesus monkeys. J Vis 2016; 15:1. [PMID: 26523737 DOI: 10.1167/15.15.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Chromatic sensitivity cannot exceed limits set by noise in the cone photoreceptors. To determine how close neurophysiological and psychophysical chromatic sensitivity come to these limits, we developed a parameter-free model of stimulus encoding in the cone outer segments, and we compared the sensitivity of the model to the psychophysical sensitivity of monkeys performing a detection task and to the sensitivity of individual V1 neurons. Modeled cones had a temporal impulse response and a noise power spectrum that were derived from in vitro recordings of macaque cones, and V1 recordings were made during performance of the detection task. The sensitivity of the simulated cone mosaic, the V1 neurons, and the monkeys were tightly yoked for low-spatiotemporal-frequency isoluminant modulations, indicating high-fidelity signal transmission for this class of stimuli. Under the conditions of our experiments and the assumptions for our model, the signal-to-noise ratio for these stimuli dropped by a factor of ∼3 between the cones and perception. Populations of weakly correlated V1 neurons narrowly exceeded the monkeys' chromatic sensitivity but fell well short of the cones' chromatic sensitivity, suggesting that most of the behavior-limiting noise lies between the cone outer segments and the output of V1. The sensitivity gap between the cones and behavior for achromatic stimuli was larger than for chromatic stimuli, indicating greater postreceptoral noise. The cone mosaic model provides a means to compare visual sensitivity across disparate stimuli and to identify sources of noise that limit visual sensitivity.
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22
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Abstract
UNLABELLED Although the rhesus monkey is used widely as an animal model of human visual processing, it is not known whether invariant visual object recognition behavior is quantitatively comparable across monkeys and humans. To address this question, we systematically compared the core object recognition behavior of two monkeys with that of human subjects. To test true object recognition behavior (rather than image matching), we generated several thousand naturalistic synthetic images of 24 basic-level objects with high variation in viewing parameters and image background. Monkeys were trained to perform binary object recognition tasks on a match-to-sample paradigm. Data from 605 human subjects performing the same tasks on Mechanical Turk were aggregated to characterize "pooled human" object recognition behavior, as well as 33 separate Mechanical Turk subjects to characterize individual human subject behavior. Our results show that monkeys learn each new object in a few days, after which they not only match mean human performance but show a pattern of object confusion that is highly correlated with pooled human confusion patterns and is statistically indistinguishable from individual human subjects. Importantly, this shared human and monkey pattern of 3D object confusion is not shared with low-level visual representations (pixels, V1+; models of the retina and primary visual cortex) but is shared with a state-of-the-art computer vision feature representation. Together, these results are consistent with the hypothesis that rhesus monkeys and humans share a common neural shape representation that directly supports object perception. SIGNIFICANCE STATEMENT To date, several mammalian species have shown promise as animal models for studying the neural mechanisms underlying high-level visual processing in humans. In light of this diversity, making tight comparisons between nonhuman and human primates is particularly critical in determining the best use of nonhuman primates to further the goal of the field of translating knowledge gained from animal models to humans. To the best of our knowledge, this study is the first systematic attempt at comparing a high-level visual behavior of humans and macaque monkeys.
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23
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Horwitz GD. What studies of macaque monkeys have told us about human color vision. Neuroscience 2014; 296:110-5. [PMID: 25445192 DOI: 10.1016/j.neuroscience.2014.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/29/2014] [Accepted: 10/01/2014] [Indexed: 11/29/2022]
Abstract
Animal models are a necessary component of systems neuroscience research. Determining which animal model to use for a given study involves a complicated calculus. Some experimental manipulations are easily made in some animal models but impossible in others. Some animal models are similar to humans with respect to particular scientific questions, and others are less so. In this review, I discuss work done in my laboratory to investigate the neural mechanisms of color vision in the rhesus macaque. The emphasis is on the strengths of the macaque model, but shortcomings are also discussed.
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Affiliation(s)
- G D Horwitz
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States; Washington National Primate Research Center, Seattle, WA, United States.
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24
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Lindbloom-Brown Z, Tait LJ, Horwitz GD. Spectral sensitivity differences between rhesus monkeys and humans: implications for neurophysiology. J Neurophysiol 2014; 112:3164-72. [PMID: 25253473 DOI: 10.1152/jn.00356.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Spectral sensitivity of humans and rhesus monkeys was compared using identical displays and similar procedures. Detection thresholds were measured for the following: 1) 15-Hz modulation of a blue and a green cathode-ray tube phosphor; 2) 15-Hz modulation of all three phosphors together; and 3) slow (<1 Hz) modulations of a blue and a green phosphor under scotopic conditions. Monkeys had lower blue-to-green threshold ratios than humans at all eccentricities tested (0.5 to 7°), consistent with a lower lens optical density in monkeys. In addition to apparently having a lower lens density than humans, monkeys were more sensitive to 15-Hz red-green isoluminant modulations than humans, an effect that cannot be explained by optical factors.
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Affiliation(s)
- Zachary Lindbloom-Brown
- Department of Physiology and Biophysics and Washington National Primate Research Center, University of Washington, Seattle, Washington
| | - Leah J Tait
- Department of Physiology and Biophysics and Washington National Primate Research Center, University of Washington, Seattle, Washington
| | - Gregory D Horwitz
- Department of Physiology and Biophysics and Washington National Primate Research Center, University of Washington, Seattle, Washington
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