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Fars J, Fernandes TP, Huchzermeyer C, Kremers J, Paramei GV. Chromatic discrimination measures in mature observers depend on the response window. Sci Rep 2022; 12:9072. [PMID: 35641546 PMCID: PMC9156755 DOI: 10.1038/s41598-022-13129-w] [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: 12/20/2021] [Accepted: 05/20/2022] [Indexed: 11/09/2022] Open
Abstract
Our past anecdotal evidence prompted that a longer response window (RW) in the Trivector test (Cambridge Colour Test) improved mature observers’ estimates of chromatic discrimination. Here, we systematically explored whether RW variation affects chromatic discrimination thresholds measured by the length of Protan, Deutan and Tritan vectors. We employed the Trivector test with three RWs: 3 s, 5 s, and 8 s. Data of 30 healthy normal trichromats were stratified as age groups: ‘young’ (20–29 years), ‘middle-aged’ (31–48 years), and ‘mature’ (57–64 years). We found that for the ‘young’ and ‘middle-aged’, the thresholds were comparable at all tested RWs. However, the RW effect was apparent for the ‘mature’ observers: their Protan and Tritan thresholds decreased at 8-s RW compared to 3-s RW; moreover, their Tritan threshold decreased at 5-s RW compared to 3-s RW. Elevated discrimination thresholds at shorter RWs imply that for accurate performance, older observers require longer stimulus exposure and are indicative of ageing effects manifested by an increase in critical processing duration. Acknowledging low numbers in our ‘middle-aged’ and ‘mature’ samples, we consider our study as pilot. Nonetheless, our findings encourage us to advocate a RW extension in the Trivector protocol for testing mature observers, to ensure veridical measures of their chromatic discrimination by disentangling these from other ageing effects—slowing down of both motor responses and visual processing.
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Affiliation(s)
- Julien Fars
- Department of Ophthalmology, University Hospital Erlangen, Schwabachanlage 6, 91054, Erlangen, Germany.
| | - Thiago P Fernandes
- Department of Psychology, Federal University of Paraiba, Cidade Universitaria S/N, Joao Pessoa, 58051-900, Brazil
| | - Cord Huchzermeyer
- Department of Ophthalmology, University Hospital Erlangen, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Jan Kremers
- Department of Ophthalmology, University Hospital Erlangen, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Galina V Paramei
- Department of Psychology, Liverpool Hope University, Hope Park, Liverpool, L16 9JD, UK.
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2
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Differences in chromatic noise suppression of luminance contrast discrimination in young and elderly people. Vis Neurosci 2022; 39:E006. [DOI: 10.1017/s0952523822000050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Abstract
Aging causes impairment of contrast sensitivity and chromatic discrimination, leading to changes in the perceptual interactions between color and luminance information. We aimed to investigate the influence of chromatic noise on luminance contrast thresholds in young and older adults. Forty participants were divided equally into Young (29.6 ± 6.3-year-old) and Elderly Groups (57.8 ± 6.6-year-old). They performed a luminance contrast discrimination task in the presence of chromatic noise maskers using a mosaic stimulus in a mosaic background. Four chromatic noise masking protocols were applied (protan, deutan, tritan, and no-noise protocols). We found that luminance contrast thresholds were significantly elevated by the addition of chromatic noise in both age groups (P < 0.05). In the Elderly group, but not the younger group, thresholds obtained in the tritan protocol were lower than those obtained from protan and deutan protocols (P < 0.05). For all protocols, the luminance contrast thresholds of elderly participants were higher than in young people (P < 0.01). Tritan chromatic noise was less effective in inhibiting luminance discrimination in elderly participants.
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Shinhmar H, Hogg C, Neveu M, Jeffery G. Weeklong improved colour contrasts sensitivity after single 670 nm exposures associated with enhanced mitochondrial function. Sci Rep 2021; 11:22872. [PMID: 34819619 PMCID: PMC8613193 DOI: 10.1038/s41598-021-02311-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 11/09/2021] [Indexed: 11/29/2022] Open
Abstract
Mitochondrial decline in ageing robs cells of ATP. However, animal studies show that long wavelength exposure (650–900 nm) over weeks partially restores ATP and improves function. The likely mechanism is via long wavelengths reducing nanoscopic interfacial water viscosity around ATP rota pumps, improving their efficiency. Recently, repeated 670 nm exposures have been used on the aged human retina, which has high-energy demands and significant mitochondrial and functional decline, to improve vision. We show here that single 3 min 670 nm exposures, at much lower energies than previously used, are sufficient to significantly improve for 1 week cone mediated colour contrast thresholds (detection) in ageing populations (37–70 years) to levels associated with younger subjects. But light needs to be delivered at specific times. In environments with artificial lighting humans are rarely dark-adapted, hence cone function becomes critical. This intervention, demonstrated to improve aged mitochondrial function can be applied to enhance colour vision in old age.
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Affiliation(s)
- Harpreet Shinhmar
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V9EL, UK
| | - Chris Hogg
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V9EL, UK
| | - Magella Neveu
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V9EL, UK
| | - Glen Jeffery
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V9EL, UK.
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Negishi I, Shinomori K. Suppression of Luminance Contrast Sensitivity by Weak Color Presentation. Front Neurosci 2021; 15:668116. [PMID: 34262428 PMCID: PMC8273178 DOI: 10.3389/fnins.2021.668116] [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: 02/15/2021] [Accepted: 05/25/2021] [Indexed: 01/01/2023] Open
Abstract
The results of psychophysical studies suggest that color in a visual scene affects luminance contrast perception. In our brain imaging studies we have found evidence of an effect of chromatic information on luminance information. The dependency of saturation on brain activity in the visual cortices was measured by functional magnetic resonance imaging (fMRI) while the subjects were observing visual stimuli consisting of colored patches of various hues manipulated in saturation (Chroma value in the Munsell color system) on an achromatic background. The results indicate that the patches suppressed luminance driven brain activity. Furthermore, the suppression was stronger rather than weaker for patches with lower saturation colors, although suppression was absent when gray patches were presented instead of colored patches. We also measured brain activity while the subjects observed only the patches (on a uniformly black background) and confirmed that the colored patches alone did not give rise to differences in brain activity for different Chroma values. The chromatic information affects the luminance information in V1, since the effect was observed in early visual cortices (V2 and V3) and the ventral pathway (hV4), as well as in the dorsal pathway (V3A/B). In addition, we conducted a psychophysical experiment in which the ability to discriminate luminance contrast on a grating was measured. Discrimination was worse when weak (less saturated) colored patches were attached to the grating than when strong (saturated) colored patches or achromatic patches were attached. The results of both the fMRI and psychophysical experiments were consistent in that the effects of color were greater in the conditions with low saturation colors.
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Affiliation(s)
- Ippei Negishi
- School of Information, Kochi University of Technology, Kami, Japan.,Department of Media Informatics, College of Informatics and Human Communication, Kanazawa Institute of Technology, Hakusan, Japan
| | - Keizo Shinomori
- School of Information, Kochi University of Technology, Kami, Japan.,Vision and Affective Science Integrated Laboratory, Research Institute, Kochi University of Technology, Kami, Japan
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Shinomori K, Komatsu H, Negishi I. Bidirectional relationships between semantic words and hues in color vision normal and deuteranopic observers. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2020; 37:A181-A201. [PMID: 32400543 DOI: 10.1364/josaa.382518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/15/2020] [Indexed: 06/11/2023]
Abstract
We previously showed that impressions of nine semantic words expressing abstract meanings (like "tranquil") can be expressed by 12 hues in a paired comparison method; in this study, White, Gray, and Black were added (Exp. 1) to the previous 12 hues. Color impressions were also estimated using a set of 35 paired words by a semantic differential (SD) method (Exp. 2). The data of nine color vision normal (CVN) and seven color vision deficient (CVD) observers (one protanope and six deuteranopes) were analyzed separately by principal component analysis (PCA). In the results of Exp. 1, all hues used as loadings were distributed in a hue-circle shape in the 2D color space of PC axes for both observer groups [however, the four bluish hues (Blue-Green to Violet) tended toward convergence]. One data set of five CVNs and five deuteranopes was analyzed together using PCA because of high concordance. In the word distribution of the CVDs in Exp. 1, because second PC scores tended to be smaller, the categorization of the words was not clear; the points of five word scores were approximately on one line, reflecting that the colors used in the paired comparison were treated in one-dimensional scaling (which correlates to lightness) in the CVDs. In the results of Exp. 2, the word distribution of loadings was similar between the CVNs and CVDs, and the color score distribution had a similar tendency of showing an ellipse-shaped hue circle; it was probably caused by their experience of being associated with color names rather than color appearance (although the radius of the short axis is shorter in the CVDs' data). The comparison of the word distribution between experiments suggests that two to five semantic word impressions can be stably expressed by hue, but the impression of other words, such as "Magnificent" for the CVNs and "Fine" for the CVDs, cannot. The hue circle is conceptually kept in the SD measurement for all observers; however, it was not kept in the paired comparison for the CVDs. The analysis of one combined data set suggests that the 2D color distribution is not caused by a 3D color system because the lightness scaling is involved in the 2D color distribution.
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Cai H, Li Y, Niringiyumukiza JD, Su P, Xiang W. Circular RNA involvement in aging: An emerging player with great potential. Mech Ageing Dev 2019; 178:16-24. [DOI: 10.1016/j.mad.2018.11.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/25/2018] [Accepted: 11/30/2018] [Indexed: 12/17/2022]
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Hathibelagal AR, Feigl B, Cao D, Zele AJ. Extrinsic cone-mediated post-receptoral noise inhibits the rod temporal impulse response function. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2018; 35:B72-B77. [PMID: 29603925 DOI: 10.1364/josaa.35.000b72] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/21/2018] [Indexed: 06/08/2023]
Abstract
We determined how extrinsic white noise correlating with cone inputs to the three primary visual pathways affects both rod-pathway temporal contrast sensitivity and the impulse response function. A four-primary photostimulator provided independent control of rod and cone photoreceptor excitations under mesopic illumination (20 photopic Td). We show that rod-pathway temporal contrast sensitivity uniformly decreases across all temporal frequencies in the presence of cone noise correlating with the inferred magnocellular, parvocellular, or koniocellular pathways. The rod-pathway temporal impulse response functions derived using the Stork-Falk procedure (with a minimum phase assumption) had lower amplitudes in the pathway-specific cone noise. Therefore, cone noise impairs rod-pathway temporal contrast sensitivity without delaying rod-pathway signal transmission.
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Shinomori K, Panorgias A, Werner JS. Age-related changes in ON and OFF responses to luminance increments and decrements. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2018; 35:B26-B34. [PMID: 29603935 DOI: 10.1364/josaa.35.000b26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/27/2017] [Indexed: 06/08/2023]
Abstract
Impulse response functions for an incremental luminous pulse (ON flash) or a decremental luminous pulse (OFF flash) were derived for twelve young (19-24 years old) and ten old (65-84 years old) observers. Thresholds were measured for two pulses separated by stimulus-onset-asynchronies from 13.3 to 186.7 ms. The pulses had a spatial Gaussian shape and were presented as increments or decrements on a 15 cd/m2 equal-energy white background, having the same chromaticity as the pulse. A spatial four-alternative forced-choice method was combined with a staircase procedure. Retinal illuminance was equated individually by heterochromatic flicker photometry and using a 2.3-mm exit pupil in a Maxwellian-view optical system to reduce the effects of age-related changes and individual variations in lens density and pupil size. Luminance ON- and OFF-impulse response functions calculated from the threshold data revealed significant age-related changes in the response amplitude of both first excitatory and first inhibitory phases. However, there were no significant changes in the time to the first peak or the second peak. These age-related changes in luminance varying ON- and OFF-impulse response functions (IRFs), reflecting putative properties of the magnocellular pathway, are discussed in relation to motion detection and the balance of ON and OFF pathways across the life span.
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Maguire J, Parry NRA, Kremers J, Murray IJ, McKeefry D. Human S-cone electroretinograms obtained by silent substitution stimulation. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2018; 35:B11-B18. [PMID: 29603933 DOI: 10.1364/josaa.35.000b11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/27/2017] [Indexed: 06/08/2023]
Abstract
We used triple silent substitution stimuli to characterize human S-cone electroretinograms (ERGs) in normal trichromats. Short-wavelength-cone (S-cone) ERGs were found to have different morphological features and temporal frequency response characteristics compared to ERGs derived from L-cones, M-cones, and rod photoreceptors in normal participants. Furthermore, in two cases of retinal pathology, blue cone monochromatism (BCM) and enhanced S-cone syndrome (ESCS), S-cone ERGs elicited by our stimuli were preserved and enhanced, respectively. The results from both normal and pathological retinae demonstrate that triple silent substitution stimuli can be used to generate ERGs that provide an assay of human S-cone function.
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10
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Shinomori K, Komatsu H. Semantic word impressions expressed by hue. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2018; 35:B55-B65. [PMID: 29603923 DOI: 10.1364/josaa.35.000b55] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/08/2018] [Indexed: 06/08/2023]
Abstract
We investigated the possibility of whether impressions of semantic words showing complex concepts could be stably expressed by hues. Using a paired comparison method, we asked ten subjects to select from a pair of hues the one that more suitably matched a word impression. We employed nine Japanese semantic words and used twelve hues from vivid tones in the practical color coordinate system. As examples of the results, for the word "vigorous" the most frequently selected color was yellow and the least selected was blue to purple; for "tranquil" the most selected was yellow to green and the least selected was red. Principal component analysis of the selection data indicated that the cumulative contribution rate of the first two components was 94.6%, and in the two-dimensional space of the components, all hues were distributed as a hue-circle shape. In addition, comparison with additional data of color impressions measured by a semantic differential method suggested that most semantic word impressions can be stably expressed by hue, but the impression of some words, such as "magnificent" cannot. These results suggest that semantic word impression can be expressed reasonably well by color, and that hues are treated as impressions from the hue circle, not from color categories.
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11
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Hall H, Medina P, Cooper DA, Escobedo SE, Rounds J, Brennan KJ, Vincent C, Miura P, Doerge R, Weake VM. Transcriptome profiling of aging Drosophila photoreceptors reveals gene expression trends that correlate with visual senescence. BMC Genomics 2017; 18:894. [PMID: 29162050 PMCID: PMC5698953 DOI: 10.1186/s12864-017-4304-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/14/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Aging is associated with functional decline of neurons and increased incidence of both neurodegenerative and ocular disease. Photoreceptor neurons in Drosophila melanogaster provide a powerful model for studying the molecular changes involved in functional senescence of neurons since decreased visual behavior precedes retinal degeneration. Here, we sought to identify gene expression changes and the genomic features of differentially regulated genes in photoreceptors that contribute to visual senescence. RESULTS To identify gene expression changes that could lead to visual senescence, we characterized the aging transcriptome of Drosophila sensory neurons highly enriched for photoreceptors. We profiled the nuclear transcriptome of genetically-labeled photoreceptors over a 40 day time course and identified increased expression of genes involved in stress and DNA damage response, and decreased expression of genes required for neuronal function. We further show that combinations of promoter motifs robustly identify age-regulated genes, suggesting that transcription factors are important in driving expression changes in aging photoreceptors. However, long, highly expressed and heavily spliced genes are also more likely to be downregulated with age, indicating that other mechanisms could contribute to expression changes at these genes. Lastly, we identify that circular RNAs (circRNAs) strongly increase during aging in photoreceptors. CONCLUSIONS Overall, we identified changes in gene expression in aging Drosophila photoreceptors that could account for visual senescence. Further, we show that genomic features predict these age-related changes, suggesting potential mechanisms that could be targeted to slow the rate of age-associated visual decline.
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Affiliation(s)
- Hana Hall
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Patrick Medina
- Department of Statistics, Purdue University, West Lafayette, IN, 47907, USA
| | - Daphne A Cooper
- Department of Biology, University of Nevada, Reno, NV, 89557, USA
| | - Spencer E Escobedo
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Jeremiah Rounds
- Department of Statistics, Purdue University, West Lafayette, IN, 47907, USA
| | - Kaelan J Brennan
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | | | - Pedro Miura
- Department of Biology, University of Nevada, Reno, NV, 89557, USA
| | | | - Vikki M Weake
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA. .,Purdue University Center for Cancer Research, Purdue University, West Lafayette, 47907, USA.
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12
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Bordt AS, Long Y, Kouyama N, Yamada ES, Hannibal J, Marshak DW. Wavy multistratified amacrine cells in the monkey retina contain immunoreactive secretoneurin. Peptides 2017. [PMID: 28641988 PMCID: PMC5556933 DOI: 10.1016/j.peptides.2017.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The goals of this study were to describe the morphology, neurotransmitter content and synaptic connections of neurons in primate retinas that contain the neuropeptide secretoneurin. Amacrine cells were labeled with antibodies to secretoneurin in macaque and baboon retinas. Their processes formed three distinct plexuses in the inner plexiform layer: one in the outermost stratum, one in the center and one in the innermost stratum. In light microscopic double immunolabeling experiments, GABA was colocalized with secretoneurin in these cells, but glycine transporter 1 and Substance P were not. ON bipolar cell axon terminals labeled with antibody to the cholecystokinin precursor, G6-gly, have ON responses to stimulation of short wavelength sensitive (S) cones. Axons of these bipolar cells made contacts with amacrine cell dendrites containing secretoneurin. Secretoneurin-IR amacrine cells also made contacts with retinal ganglion cell dendrites labeled with antibody to the photopigment melanopsin, which have OFF responses to stimulation of S cones. Using electron microscopic immunolabeling, 436 synapses from macaque retina were analyzed. Axons from bipolar cells were identified by their characteristic synaptic ribbons; their synaptic densities were asymmetric like those of excitatory synapses in the brain. Amacrine cells made and received conventional synapses with symmetric synaptic densities, like those of inhibitory synapses in the brain. Ganglion cell dendrites were identified by their absence of presynaptic specializations; they received inputs from both amacrine cells and bipolar cells. The majority of inputs to the secretoneurin-IR amacrine cells were from other amacrine cells, but they also received 21% of their input from bipolar cells. They directed most of their output, 54%, to amacrine cells, but there were many synapses onto bipolar cell axons and ganglion cell dendrites, as well. The synaptic connections were very similar in the three plexuses with one notable exception; output synapses to bipolar cells were significantly less common in the innermost one, where the S-ON bipolar cells terminate. Taken together, these findings suggest that the secretoneurin-IR amacrine cells in primates receive excitatory input from S-ON bipolar cells and, in turn, inhibit intrinsically photosensitive retinal ganglion cells.
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Affiliation(s)
- Andrea S Bordt
- Department of Neurobiology and Anatomy, McGovern Medical School, Houston, TX, USA
| | - Ye Long
- Department of Neurobiology and Anatomy, McGovern Medical School, Houston, TX, USA; Department of Ophthalmology and Visual Science, McGovern Medical School, Houston, TX, USA
| | - Nobuo Kouyama
- Nursing School, Tokyo Women's Medical University, Shizuoka, Japan
| | - Elizabeth S Yamada
- Institute of Biological Sciences, Federal University of Pará, Belem, Brazil
| | - Jens Hannibal
- Department of Clinical Biochemistry, Bispebjerg Hospital, Copenhagen University, Copenhagen, Denmark
| | - David W Marshak
- Department of Neurobiology and Anatomy, McGovern Medical School, Houston, TX, USA; Department of Ophthalmology and Visual Science, McGovern Medical School, Houston, TX, USA.
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Weinrich TW, Powner MB, Lynch A, Jonnal RS, Werner JS, Jeffery G. No evidence for loss of short-wavelength sensitive cone photoreceptors in normal ageing of the primate retina. Sci Rep 2017; 7:46346. [PMID: 28402329 PMCID: PMC5389352 DOI: 10.1038/srep46346] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 03/14/2017] [Indexed: 11/09/2022] Open
Abstract
In old world primates including humans, cone photoreceptors are classified according to their maximal sensitivity at either short (S, blue), middle (M, green) or long (L, red) wavelengths. Colour discrimination studies show that the S-cone pathway is selectively affected by age and disease, and psychophysical models implicate their loss. Photoreceptors have high metabolic demand and are susceptible to age or disease-related losses in oxygen and nutrient supply. Hence 30% of rods are lost over life. While comparable losses are not seen in cones, S-cones comprise less than 10% of the cone population, so significant loss would be undetected in total counts. Here we examine young and aged primate retinae stained to distinguish S from M/L-cones. We show there is no age-related cone loss in either cone type and that S-cones are as regularly distributed in old as young primates. We propose that S-cone metabolism is less flexible than in their M/L counterparts, making them more susceptible to deficits in normal cellular function. Hypoxia is a feature of the ageing retina as extracellular debris accumulates between photoreceptors and their blood supply which likely impacts S-cone function. However, that these cells remain in the ageing retina suggests the potential for functional restoration.
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Affiliation(s)
- Tobias W Weinrich
- Institute of Ophthalmology; University College London, London, EC1V 9EL, United Kingdom
| | - Michael B Powner
- Division of Optometry and Visual Sciences; City, University of London, London, EC1V 0HB, United Kingdom
| | - Aisling Lynch
- Institute of Ophthalmology; University College London, London, EC1V 9EL, United Kingdom
| | - Ravi S Jonnal
- Department of Ophthalmology and Vision Science; University of California, Davis, Sacramento, CA 95817, United States of America
| | - John S Werner
- Department of Ophthalmology and Vision Science; University of California, Davis, Sacramento, CA 95817, United States of America
| | - Glen Jeffery
- Institute of Ophthalmology; University College London, London, EC1V 9EL, United Kingdom
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Shinomori K, Panorgias A, Werner JS. Discrimination thresholds of normal and anomalous trichromats: Model of senescent changes in ocular media density on the Cambridge Colour Test. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2016; 33:A65-76. [PMID: 26974943 PMCID: PMC5316232 DOI: 10.1364/josaa.33.000a65] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Age-related changes in chromatic discrimination along dichromatic confusion lines were measured with the Cambridge Colour Test (CCT). One hundred and sixty-two individuals (16 to 88 years old) with normal Rayleigh matches were the major focus of this paper. An additional 32 anomalous trichromats classified by their Rayleigh matches were also tested. All subjects were screened to rule out abnormalities of the anterior and posterior segments. Thresholds on all three chromatic vectors measured with the CCT showed age-related increases. Protan and deutan vector thresholds increased linearly with age while the tritan vector threshold was described with a bilinear model. Analysis and modeling demonstrated that the nominal vectors of the CCT are shifted by senescent changes in ocular media density, and a method for correcting the CCT vectors is demonstrated. A correction for these shifts indicates that classification among individuals of different ages is unaffected. New vector thresholds for elderly observers and for all age groups are suggested based on calculated tolerance limits.
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Affiliation(s)
- Keizo Shinomori
- School of Information, Kochi University of Technology, Tosayamada-Miyanokuchi, Kami, Kochi 782-8502, Japan
- Vision and Affective Science Integrated Research Laboratory, Research Institute, Kochi University of Technology, Kochi, Japan
- Corresponding author:
| | - Athanasios Panorgias
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, California 95813, USA
- Department of Vision Science, New England College of Optometry, Boston, Massachusetts 02115, USA
| | - John S. Werner
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, California 95813, USA
- Department of Experimental Psychology, University of Cambridge, Cambridge, UK
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Ma R, Kawamoto KI, Shinomori K. Color constancy of color-deficient observers under illuminations defined by individual color discrimination ellipsoids. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2016; 33:A283-A299. [PMID: 26974935 DOI: 10.1364/josaa.33.00a283] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We explored the color constancy mechanisms of color-deficient observers under red, green, blue, and yellow illuminations. The red and green illuminations were defined individually by the longer axis of the color discrimination ellipsoid measured by the Cambridge Colour Test. Four dichromats (3 protanopes and 1 deuteranope), two anomalous trichromats (2 deuteranomalous observers), and five color-normal observers were asked to complete the color constancy task by making a simultaneous paper match under asymmetrical illuminations in haploscopic view on a monitor. The von Kries adaptation model was applied to estimate the cone responses. The model fits showed that for all color-deficient observers under all illuminations, the adjustment of the S-cone response or blue-yellow chromatically opponent responses modeled with the simple assumption of cone deletion in a certain type (S-M, S-L or S-(L+M)) was consistent with the principle of the von Kries model. The degree of adaptation was similar to that of color-normal observers. The results indicate that the color constancy of color-deficient observers is mediated by the simplified blue-yellow color system with a von Kries-type adaptation effect, even in the case of brightness match, as well as by a possible cone-level adaptation to the S-cone when the illumination produces a strong S-cone stimulation, such as blue illumination.
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Werner JS. The Verriest Lecture: Short-wave-sensitive cone pathways across the life span. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2016; 33:A104-22. [PMID: 26974914 PMCID: PMC5330185 DOI: 10.1364/josaa.33.00a104] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Structurally and functionally, the short-wave-sensitive (S) cone pathways are thought to decline more rapidly with normal aging than the middle- and long-wave-sensitive cone pathways. This would explain the celebrated results by Verriest and others demonstrating that the largest age-related color discrimination losses occur for stimuli on a tritan axis. Here, we challenge convention, arguing from psychophysical data that selective S-cone pathway losses do not cause declines in color discrimination. We show substantial declines in chromatic detection and discrimination, as well as in temporal and spatial vision tasks, that are mediated by S-cone pathways. These functional losses are not, however, unique to S-cone pathways. Finally, despite reduced photon capture by S cones, their postreceptoral pathways provide robust signals for the visual system to renormalize itself to maintain nearly stable color perception across the life span.
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Affiliation(s)
- John S. Werner
- University of California, Davis, Department of Ophthalmology & Vision Science, Department of Neurobiology, Physiology & Behavior, Sacramento, California 95817, USA
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Hofmann L, Palczewski K. Advances in understanding the molecular basis of the first steps in color vision. Prog Retin Eye Res 2015; 49:46-66. [PMID: 26187035 DOI: 10.1016/j.preteyeres.2015.07.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/07/2015] [Accepted: 07/09/2015] [Indexed: 01/05/2023]
Abstract
Serving as one of our primary environmental inputs, vision is the most sophisticated sensory system in humans. Here, we present recent findings derived from energetics, genetics and physiology that provide a more advanced understanding of color perception in mammals. Energetics of cis-trans isomerization of 11-cis-retinal accounts for color perception in the narrow region of the electromagnetic spectrum and how human eyes can absorb light in the near infrared (IR) range. Structural homology models of visual pigments reveal complex interactions of the protein moieties with the light sensitive chromophore 11-cis-retinal and that certain color blinding mutations impair secondary structural elements of these G protein-coupled receptors (GPCRs). Finally, we identify unsolved critical aspects of color tuning that require future investigation.
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Affiliation(s)
- Lukas Hofmann
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
| | - Krzysztof Palczewski
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
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Yang HJ, Ratnapriya R, Cogliati T, Kim JW, Swaroop A. Vision from next generation sequencing: multi-dimensional genome-wide analysis for producing gene regulatory networks underlying retinal development, aging and disease. Prog Retin Eye Res 2015; 46:1-30. [PMID: 25668385 PMCID: PMC4402139 DOI: 10.1016/j.preteyeres.2015.01.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/18/2015] [Accepted: 01/21/2015] [Indexed: 01/10/2023]
Abstract
Genomics and genetics have invaded all aspects of biology and medicine, opening uncharted territory for scientific exploration. The definition of "gene" itself has become ambiguous, and the central dogma is continuously being revised and expanded. Computational biology and computational medicine are no longer intellectual domains of the chosen few. Next generation sequencing (NGS) technology, together with novel methods of pattern recognition and network analyses, has revolutionized the way we think about fundamental biological mechanisms and cellular pathways. In this review, we discuss NGS-based genome-wide approaches that can provide deeper insights into retinal development, aging and disease pathogenesis. We first focus on gene regulatory networks (GRNs) that govern the differentiation of retinal photoreceptors and modulate adaptive response during aging. Then, we discuss NGS technology in the context of retinal disease and develop a vision for therapies based on network biology. We should emphasize that basic strategies for network construction and analyses can be transported to any tissue or cell type. We believe that specific and uniform guidelines are required for generation of genome, transcriptome and epigenome data to facilitate comparative analysis and integration of multi-dimensional data sets, and for constructing networks underlying complex biological processes. As cellular homeostasis and organismal survival are dependent on gene-gene and gene-environment interactions, we believe that network-based biology will provide the foundation for deciphering disease mechanisms and discovering novel drug targets for retinal neurodegenerative diseases.
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Affiliation(s)
- Hyun-Jin Yang
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Rinki Ratnapriya
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Tiziana Cogliati
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Jung-Woong Kim
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Anand Swaroop
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA.
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Abstract
We review the features of the S-cone system that appeal to the psychophysicist and summarize the celebrated characteristics of S-cone mediated vision. Two factors are emphasized: First, the fine stimulus control that is required to isolate putative visual mechanisms and second, the relationship between physiological data and psychophysical approaches. We review convergent findings from physiology and psychophysics with respect to asymmetries in the retinal wiring of S-ON and S-OFF visual pathways, and the associated treatment of increments and decrements in the S-cone system. Beyond the retina, we consider the lack of S-cone projections to superior colliculus and the use of S-cone stimuli in experimental psychology, for example to address questions about the mechanisms of visually driven attention. Careful selection of stimulus parameters enables psychophysicists to produce entirely reversible, temporary, "lesions," and to assess behavior in the absence of specific neural subsystems.
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20
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Abstract
In all of the mammalian species studied to date, the short-wavelength-sensitive (S) cones and the S-cone bipolar cells that receive their input are very similar, but the retinal ganglion cells that receive synapses from the S-cone bipolar cells appear to be quite different. Here, we review the literature on mammalian retinal ganglion cells that respond selectively to stimulation of S-cones and respond with opposite polarity to longer wavelength stimuli. There are at least three basic mechanisms to generate these color-opponent responses, including: (1) opponency is generated in the outer plexiform layer by horizontal cells and is conveyed to the ganglion cells via S-cone bipolar cells, (2) inputs from bipolar cells with different cone inputs and opposite response polarity converge directly on the ganglion cells, and (3) inputs from S-cone bipolar cells are inverted by S-cone amacrine cells. These are not mutually exclusive; some mammalian ganglion cells that respond selectively to S-cone stimulation seem to utilize at least two of them. Based on these findings, we suggest that the small bistratified ganglion cells described in primates are not the ancestral type, as proposed previously. Instead, the known types of ganglion cells in this pathway evolved from monostratified ancestral types and became bistratified in some mammalian lineages.
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Cunea A, Powner MB, Jeffery G. Death by color: differential cone loss in the aging mouse retina. Neurobiol Aging 2014; 35:2584-2591. [PMID: 24929970 DOI: 10.1016/j.neurobiolaging.2014.05.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 05/05/2014] [Accepted: 05/11/2014] [Indexed: 11/17/2022]
Abstract
Differential cell death is a common feature of aging and age-related disease. In the retina, 30% of rod photoreceptors are lost over life in humans and rodents. However, studies have failed to show age-related cell death in mouse cone photoreceptors, which is surprising because cone physiological function declines with age. Moreover in human, differential loss of short wavelength cone function is an aspect of age-related retinal disease. Here, cones are examined in young (3-month-old) and aged (12-month-old) C57 mice and also in complement factor H knock out mice (CFH-/-) that have been proposed as a murine model of age-related macular degeneration. In vivo imaging showed significant age-related reductions in outer retinal thickness in both groups over this period. Immunostaining for opsins revealed a specific significant decline of >20% for the medium/long (M/L)-wavelength cones but only in the periphery. S cones numbers were not significantly affected by age. This differential cell loss was backed up with quantitative real-time polymerase chain reaction for the 2 opsins, again showing S opsin was unaffected, but that M/L opsin was reduced particularly in CFH-/- mice. These results demonstrate aged cone loss, but surprisingly, in both genotypes, it is only significant in the peripheral ventral retina and focused on the M/L population and not S cones. We speculate that there may be fundamental differences in differential cone loss between human and mouse that may question the validity of mouse models of human outer retinal aging and pathology.
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Affiliation(s)
- Alexander Cunea
- Institute of Ophthalmology, University College London, London, UK
| | - Michael B Powner
- Institute of Ophthalmology, University College London, London, UK
| | - Glen Jeffery
- Institute of Ophthalmology, University College London, London, UK.
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22
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Abstract
Color information is encoded by two parallel pathways in the mammalian retina. One pathway compares signals from long- and middle-wavelength sensitive cones and generates red-green opponency. The other compares signals from short- and middle-/long-wavelength sensitive cones and generates blue-green (yellow) opponency. Whereas both pathways operate in trichromatic primates (including humans), the fundamental, phylogenetically ancient color mechanism shared among most mammals is blue-green opponency. In this review, we summarize the current understanding of how signals from short-wavelength sensitive cones are processed in the primate and nonprimate mammalian retina, with a focus on the inner plexiform layer where bipolar, amacrine, and ganglion cell processes interact to facilitate the generation of blue-green opponency.
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23
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Shi L, Shinomori K. Amplitude difference and similar time course of impulse responses in positive- and negative-contrast detection. Vision Res 2013. [PMID: 23200865 DOI: 10.1016/j.visres.2012.11.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Temporal impulse response functions (IRFs) were measured to investigate the temporal characteristics of positive- and negative-contrast detection in human vision. The IRFs were estimated using models from sequential double-pulse thresholds measured by the psi method. The results indicated that thresholds for positive contrast detection were significantly higher than those for negative contrast detection. However, positive- and negative-contrast IRFs were similar except for the first peak amplitude, reflecting the difference in sensitivity that originates from the summation operation rather than the linear filtering of the visual system.
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Affiliation(s)
- Lin Shi
- Department of Engineering, Graduate School of Engineering, Kochi University of Technology, Japan.
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