1
|
Marmoy OR, Tekavčič Pompe M, Kremers J. Chromatic visual evoked potentials: A review of physiology, methods and clinical applications. Prog Retin Eye Res 2024; 101:101272. [PMID: 38761874 DOI: 10.1016/j.preteyeres.2024.101272] [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: 07/20/2023] [Revised: 05/06/2024] [Accepted: 05/10/2024] [Indexed: 05/20/2024]
Abstract
Objective assessment of the visual system can be performed electrophysiologically using the visual evoked potential (VEP). In many clinical circumstances, this is performed using high contrast achromatic patterns or diffuse flash stimuli. These methods are clinically valuable but they may only assess a subset of possible physiological circuitries within the visual system, particularly those involved in achromatic (luminance) processing. The use of chromatic VEPs (cVEPs) in addition to standard VEPs can inform us of the function or dysfunction of chromatic pathways. The chromatic VEP has been well studied in human health and disease. Yet, to date our knowledge of their underlying mechanisms and applications remains limited. This likely reflects a heterogeneity in the methodology, analysis and conclusions of different works, which leads to ambiguity in their clinical use. This review sought to identify the primary methodologies employed for recording cVEPs. Furthermore cVEP maturation and application in understanding the function of the chromatic system under healthy and diseased conditions are reviewed. We first briefly describe the physiology of normal colour vision, before describing the methodologies and historical developments which have led to our understanding of cVEPs. We thereafter describe the expected maturation of the cVEP, followed by reviewing their application in several disorders: congenital colour vision deficiencies, retinal disease, glaucoma, optic nerve and neurological disorders, diabetes, amblyopia and dyslexia. We finalise the review with recommendations for testing and future directions.
Collapse
Affiliation(s)
- Oliver R Marmoy
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK; UCL-GOS Institute of Child Health, University College London, London, UK.
| | - Manca Tekavčič Pompe
- University Eye Clinic, University Medical Centre Ljubljana, Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Slovenia
| | - Jan Kremers
- Section of Retinal Physiology, University Hospital Erlangen, Germany
| |
Collapse
|
2
|
Chien SE, Yeh SL, Yamashita W, Tsujimura SI. Enhanced human contrast sensitivity with increased stimulation of melanopsin in intrinsically photosensitive retinal ganglion cells. Vision Res 2023; 209:108271. [PMID: 37331304 DOI: 10.1016/j.visres.2023.108271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 05/15/2023] [Accepted: 05/22/2023] [Indexed: 06/20/2023]
Abstract
The intrinsically photosensitive retinal ganglion cells (ipRGCs) are known to serve non-image-forming functions, such as photoentrainment of the circadian rhythm and pupillary light reflex. However, how they affect human spatial vision is largely unknown. The spatial contrast sensitivity function (CSF), which measures contrast sensitivity as a function of spatial frequency, was used in the current study to investigate the function of ipRGCs in pattern vision. To compare the effects of different background lights on the CSF, we utilized the silent substitution technique. We manipulated the stimulation level of melanopsin (i.e., the visual pigment of ipRGCs) from the background light while keeping the cone stimulations constant, or vice versa. We conducted four experiments to measure the CSFs at various spatial frequencies, eccentricities, and levels of background luminance. Results showed that melanopsin stimulation from the background light enhances spatial contrast sensitivity across different eccentricities and luminance levels. Our finding that melanopsin contributes to CSF, combined with the receptive field analysis, suggests a role for the magnocellular pathway and challenges the conventional view that ipRGCs are primarily responsible for non-visual functions.
Collapse
Affiliation(s)
- Sung-En Chien
- Department of Psychology, National Taiwan University, Taipei 10617, Taiwan; Ganzin Technology Inc., New Taipei City 23141, Taiwan
| | - Su-Ling Yeh
- Department of Psychology, National Taiwan University, Taipei 10617, Taiwan; Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei 10617, Taiwan; Neurobiology and Cognitive Science Center, National Taiwan University, Taipei 10617, Taiwan; Center for Advanced Studies in the Behavioral Sciences, Stanford University, Stanford, CA 94305, USA.
| | - Wakayo Yamashita
- Faculty of Science and Engineering, Kagoshima University, Kagoshima 890-0065, Japan
| | - Sei-Ichi Tsujimura
- Faculty of Science and Engineering, Kagoshima University, Kagoshima 890-0065, Japan; Faculty of Design and Architecture, Nagoya City University, Nagoya 467-8501, Japan.
| |
Collapse
|
3
|
Portengen BL, Porro GL, Imhof SM, Naber M. The Trade-Off Between Luminance and Color Contrast Assessed With Pupil Responses. Transl Vis Sci Technol 2023; 12:15. [PMID: 36622687 PMCID: PMC9838585 DOI: 10.1167/tvst.12.1.15] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Purpose A scene consisting of a white stimulus on a black background incorporates strong luminance contrast. When both stimulus and background receive different colors, luminance contrast decreases but color contrast increases. Here, we sought to characterize the pattern of stimulus salience across varying trade-offs of color and luminance contrasts by using the pupil light response. Methods Three experiments were conducted with 17, 16, and 17 healthy adults. For all experiments, a flickering stimulus (2 Hz; alternating color to black) was presented superimposed on a background with a complementary color to the stimulus (i.e., opponency colors in human color perception: blue and yellow for Experiment 1, red and green for Experiment 2, and equiluminant red and green for Experiment 3). Background luminance varied between 0% and 45% to trade off luminance and color contrast with the stimulus. By comparing the locus of the optimal trade-off between color and luminance across different color axes, we explored the generality of the trade-off. Results The strongest pupil responses were found when a substantial amount of color contrast was present (at the expense of luminance contrast). Pupil response amplitudes increased by 15% to 30% after the addition of color contrast. An optimal pupillary responsiveness was reached at a background luminance setting of 20% to 35% color contrast across several color axes. Conclusions These findings suggest that a substantial component of pupil light responses incorporates color processing. More sensitive pupil responses and more salient stimulus designs can be achieved by adding subtle levels of color contrast between stimulus and background. Translational Relevance More robust pupil responses will enhance tests of the visual field with pupil perimetry.
Collapse
Affiliation(s)
- Brendan L. Portengen
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands,Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| | - Giorgio L. Porro
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Saskia M. Imhof
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marnix Naber
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| |
Collapse
|
4
|
Uprety S, Adhikari P, Feigl B, Zele AJ. Melanopsin photoreception differentially modulates rod-mediated and cone-mediated human temporal vision. iScience 2022; 25:104529. [PMID: 35754721 PMCID: PMC9218364 DOI: 10.1016/j.isci.2022.104529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/04/2022] [Accepted: 05/30/2022] [Indexed: 11/17/2022] Open
Abstract
To evaluate the nature of interactions between visual pathways transmitting the slower melanopsin and faster rod and cone signals, we implement a temporal phase summation paradigm in human observers using photoreceptor-directed stimuli. We show that melanopsin stimulation interacts with and alters both rod-mediated and cone-mediated vision regardless of whether it is perceptually visible or not. Melanopsin-rod interactions result in either inhibitory or facilitatory summation depending on the temporal frequency and photoreceptor pathway contrast sensitivity. Moreover, by isolating rod vision, we reveal a bipartite intensity response property of the rod pathway in photopic lighting that extends its operational range at lower frequencies to beyond its classic saturation limits but at the expense of attenuating sensitivity at higher frequencies. In comparison, melanopsin-cone interactions always lead to facilitation. These interactions can be described by linear or probability summations and potentially involve multiple intraretinal and visual cortical pathways to set human visual contrast sensitivity. Melanopsin ipRGCs support vision independent of the rod and cone signals Rod pathways mediate robust visual responses in daylight Temporal contrast sensitivity is contingent on the melanopsin excitation level Visual performance is collectively regulated by melanopsin, rod and cone pathways
Collapse
Affiliation(s)
- Samir Uprety
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
| | - Prakash Adhikari
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
| | - Beatrix Feigl
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,Queensland Eye Institute, Brisbane, QLD 4101, Australia
| | - Andrew J Zele
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
| |
Collapse
|
5
|
Kim YJ, Peterson BB, Crook JD, Joo HR, Wu J, Puller C, Robinson FR, Gamlin PD, Yau KW, Viana F, Troy JB, Smith RG, Packer OS, Detwiler PB, Dacey DM. Origins of direction selectivity in the primate retina. Nat Commun 2022; 13:2862. [PMID: 35606344 PMCID: PMC9126974 DOI: 10.1038/s41467-022-30405-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/27/2022] [Indexed: 12/22/2022] Open
Abstract
From mouse to primate, there is a striking discontinuity in our current understanding of the neural coding of motion direction. In non-primate mammals, directionally selective cell types and circuits are a signature feature of the retina, situated at the earliest stage of the visual process. In primates, by contrast, direction selectivity is a hallmark of motion processing areas in visual cortex, but has not been found in the retina, despite significant effort. Here we combined functional recordings of light-evoked responses and connectomic reconstruction to identify diverse direction-selective cell types in the macaque monkey retina with distinctive physiological properties and synaptic motifs. This circuitry includes an ON-OFF ganglion cell type, a spiking, ON-OFF polyaxonal amacrine cell and the starburst amacrine cell, all of which show direction selectivity. Moreover, we discovered that macaque starburst cells possess a strong, non-GABAergic, antagonistic surround mediated by input from excitatory bipolar cells that is critical for the generation of radial motion sensitivity in these cells. Our findings open a door to investigation of a precortical circuitry that computes motion direction in the primate visual system.
Collapse
Affiliation(s)
- Yeon Jin Kim
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
| | - Beth B Peterson
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
| | - Joanna D Crook
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
| | - Hannah R Joo
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
| | - Jiajia Wu
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Christian Puller
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
| | - Farrel R Robinson
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
- Washington National Primate Research Center, Seattle, WA, 98195, USA
| | - Paul D Gamlin
- Department of Ophthalmology and Vision Sciences, University of Alabama at Birmingham, Birmingham, AL, 35294-4390, USA
| | - King-Wai Yau
- Departments of Neuroscience and Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205-2185, USA
| | - Felix Viana
- Institute of Neuroscience, UMH-CSIC, San Juan de Alicante, 03550, Spain
| | - John B Troy
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Robert G Smith
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Orin S Packer
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA
| | - Peter B Detwiler
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, 98195, USA
| | - Dennis M Dacey
- Department of Biological Structure, University of Washington, Seattle, WA, 98195, USA.
- Washington National Primate Research Center, Seattle, WA, 98195, USA.
| |
Collapse
|
6
|
Kremers J, Aher AJ, Parry NRA, Patel NB, Frishman LJ. Comparison of macaque and human L- and M-cone driven electroretinograms. Exp Eye Res 2021; 206:108556. [PMID: 33794198 DOI: 10.1016/j.exer.2021.108556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 03/05/2021] [Accepted: 03/22/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE The macaque retina is often used as a model for the human retina. However, there are only a handful of direct in vivo comparisons of the retinal physiology in humans and macaques. In the current study, ERG responses to luminance, L-cone isolating and M-cone isolating stimuli with sinusoidal, sawtooth and square wave temporal profiles were measured. The results were compared with those obtained from human observers. METHODS The responses from five anesthetized adult macaques were measured. Full field stimuli were created. L- and M-cone isolating stimuli were based on the triple silent substitution technique. Sinusoidal stimuli had temporal frequencies between 4 and 56 Hz in 4 Hz steps. Sawtooth stimuli with rapid-on ramp-off and with rapid-off ramp-on excitation profiles had a frequency of 4 Hz. Square stimuli were presented at 2 Hz. RESULTS Macaque and human ERGs in response to L- and M-cone isolating stimuli reflect L/M opponency and luminance activity. In responses to sine waves, cone opponency dominates at low temporal frequencies (4-12 Hz); luminance dominates at high temporal frequencies. The responses to sawtooth and square wave stimuli reflect a mixture of chromatic and luminance activity. L:M response ratios vary between individuals both in macaques and humans. Macaques show more complex responses, including greater second harmonic contributions than those in humans. CONCLUSIONS Macaque and human ERGs share basic underlying mechanisms reflecting L/M opponency and luminance activity. There may be quantitative differences possibly reflecting differences in contributions of inner retinal mechanisms to the ERGs.
Collapse
Affiliation(s)
- Jan Kremers
- Section for Retinal Physiology, University Hospital Erlangen, 91054, Erlangen, Germany.
| | - Avinash J Aher
- Section for Retinal Physiology, University Hospital Erlangen, 91054, Erlangen, Germany
| | - Neil R A Parry
- Vision Science Centre, Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK; Faculty of Biology, Medicine and Health, University of Manchester, UK
| | - Nimesh B Patel
- Department of Vision Sciences, College of Optometry, University of Houston, Houston, TX, USA
| | - Laura J Frishman
- Department of Vision Sciences, College of Optometry, University of Houston, Houston, TX, USA
| |
Collapse
|
7
|
Harris E, Mihai D, Hare J. How Convolutional Neural Network Architecture Biases Learned Opponency and Color Tuning. Neural Comput 2021; 33:858-898. [PMID: 33400902 DOI: 10.1162/neco_a_01356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/06/2020] [Indexed: 11/04/2022]
Abstract
Recent work suggests that changing convolutional neural network (CNN) architecture by introducing a bottleneck in the second layer can yield changes in learned function. To understand this relationship fully requires a way of quantitatively comparing trained networks. The fields of electrophysiology and psychophysics have developed a wealth of methods for characterizing visual systems that permit such comparisons. Inspired by these methods, we propose an approach to obtaining spatial and color tuning curves for convolutional neurons that can be used to classify cells in terms of their spatial and color opponency. We perform these classifications for a range of CNNs with different depths and bottleneck widths. Our key finding is that networks with a bottleneck show a strong functional organization: almost all cells in the bottleneck layer become both spatially and color opponent, and cells in the layer following the bottleneck become nonopponent. The color tuning data can further be used to form a rich understanding of how color a network encodes color. As a concrete demonstration, we show that shallower networks without a bottleneck learn a complex nonlinear color system, whereas deeper networks with tight bottlenecks learn a simple channel opponent code in the bottleneck layer. We develop a method of obtaining a hue sensitivity curve for a trained CNN that enables high-level insights that complement the low-level findings from the color tuning data. We go on to train a series of networks under different conditions to ascertain the robustness of the discussed results. Ultimately our methods and findings coalesce with prior art, strengthening our ability to interpret trained CNNs and furthering our understanding of the connection between architecture and learned representation. Trained models and code for all experiments are available at https://github.com/ecs-vlc/opponency.
Collapse
Affiliation(s)
- Ethan Harris
- Vision Learning and Control, Electronics and Computer Science, University of Southampton, Southampton SO17 1B J, U.K.,
| | - Daniela Mihai
- Vision Learning and Control, Electronics and Computer Science, University of Southampton, Southampton SO17 1B J, U.K.,
| | - Jonathon Hare
- Vision Learning and Control, Electronics and Computer Science, University of Southampton, Southampton SO17 1B J, U.K.,
| |
Collapse
|
8
|
Abstract
We as a couple spent 50 years working in visual psychophysics of color vision, temporal vision, and luminance adaptation. We sought collaborations with ophthalmologists, anatomists, physiologists, physicists, and psychologists, aiming to relate visual psychophysics to the underlying physiology of the primate retina. This review describes our journey and reflections in exploring the visual system.
Collapse
Affiliation(s)
- Joel Pokorny
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois 60637, USA;,
| | - Vivianne C. Smith
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois 60637, USA;,
| |
Collapse
|
9
|
Chien SE, Chen YC, Matsumoto A, Yamashita W, Shih KT, Tsujimura SI, Yeh SL. The modulation of background color on perceiving audiovisual simultaneity. Vision Res 2020; 172:1-10. [PMID: 32388209 DOI: 10.1016/j.visres.2020.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 04/15/2020] [Accepted: 04/16/2020] [Indexed: 11/28/2022]
Abstract
Perceiving simultaneity is critical in integrating visual and auditory signals that give rise to a unified perception. We examined whether background color modulates people's perception of audiovisual simultaneity. Two hypotheses were proposed and examined: (1) the red-impairment hypothesis: visual processing speed deteriorates when viewing a red background because the magnocellular system is inhibited by red light; and (2) the blue-enhancement hypothesis: the detection of both visual and auditory signals is enhanced when viewing a blue background because it stimulates the blue-light sensitive intrinsically photosensitive retinal ganglion cells (ipRGCs), which trigger a higher alert state. Participants were exposed to different backgrounds while performing an audiovisual simultaneity judgment (SJ) task: a flash and a beep were presented at pre-designated stimulus onset asynchronies (SOAs) and participants judged whether or not the two stimuli were presented simultaneously. Experiment 1 demonstrated a shift of the point of subjective simultaneity (PSS) toward the visual-leading condition in the red compared to the blue background when the flash was presented in the periphery. In Experiment 2, the stimulation of ipRGCs was specifically manipulated to test the blue-enhancement hypothesis. The results showed no support for this hypothesis, perhaps due to top-down cortical modulations. Taken together, the shift of PSS toward the visual-leading condition in the red background was attributed to impaired visual processing speed with respect to auditory processing speed, caused by the inhibition of the magnocellular system under red light.
Collapse
Affiliation(s)
- Sung-En Chien
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Yi-Chuan Chen
- Department of Medicine, Mackay Medical College, New Taipei City, Taiwan
| | - Akiko Matsumoto
- Faculty of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Wakayo Yamashita
- Faculty of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Kuaug-Tsu Shih
- Graduate Institute of Communication Engineering, National Taiwan University, Taipei, Taiwan
| | - Sei-Ichi Tsujimura
- Faculty of Design and Architecture, Nagoya City University, Nagoya, Japan
| | - Su-Ling Yeh
- Department of Psychology, National Taiwan University, Taipei, Taiwan; Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan; Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan; Center for Artificial Intelligence and Advanced Robotics, National Taiwan University, Taipei, Taiwan; Center for the Advanced Study in the Behavioral Sciences, Stanford University, USA.
| |
Collapse
|
10
|
|
11
|
Aher AJ, Jacob MM, Kremers J. High-frequency characteristics of L- and M-cone driven electroretinograms. Vision Res 2019; 159:35-41. [PMID: 30926305 DOI: 10.1016/j.visres.2019.03.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 03/14/2019] [Accepted: 03/25/2019] [Indexed: 10/27/2022]
Abstract
Electroretinograms (ERGs) elicited by high temporal frequency (26-95 Hz) L- and M-cone isolating sine-wave stimuli were investigated in human observers for full-field (FF) and different spatially restricted stimulus sizes (70°, 50°, 30°, and 10° diameter). Responses to L- and M-cone isolating FF stimuli were maximal around 48 Hz and decreased gradually with increasing temporal frequency up to 95 Hz. The response maximum was shifted to about 30-32 Hz for both L- and M-cone driven responses obtained with spatially restricted stimuli. The M-cone driven responses could only be measured up to 54 Hz with 70° stimuli. The response amplitudes for L- and M-cones and L-/M-cone amplitude ratios decreased with decreasing stimulus size. The ERG response phases to L- and M-cone isolating stimuli decreased with increasing temporal frequency and were about -160° apart for all stimulus sizes up to 34 Hz. Further increase in the temporal frequency displayed a positive correlation between stimulus size and L-M phase difference. The ERG data indicate that the responses evoked by high temporal frequency cone isolating stimuli reflect two mechanisms, one that is more centrally located and displays a maximum at about 30-32 Hz and a peripheral mechanism that is sensitive to higher temporal modulations. We propose that the peripheral mechanism (FF ERGs) reflects magnocellular activity, whereas the central mechanism (ERGs with spatially restricted stimuli) is based on a parvocellular activity up to about 30 Hz.
Collapse
Affiliation(s)
- Avinash J Aher
- Department of Ophthalmology, University Hospital Erlangen, Schwabachanlage 6, Erlangen 91054, Germany
| | - Mellina M Jacob
- Department of Ophthalmology, University Hospital Erlangen, Schwabachanlage 6, Erlangen 91054, Germany; Laboratory of Tropical Neurology, Institute of Biological Sciences, UFPA, Augusto Correa St., Number 01, Belém CEP 66075-110, Brazil
| | - Jan Kremers
- Department of Ophthalmology, University Hospital Erlangen, Schwabachanlage 6, Erlangen 91054, Germany; School of Optometry and Vision Science, University of Bradford, Richmond Rd., Bradford, West Yorkshire BD7 1DP, United Kingdom.
| |
Collapse
|
12
|
Barboni MTS, Hauzman E, Nagy BV, Martins CMG, Aher AJ, Tsai TI, Bonci DMO, Ventura DF, Kremers J. Electrodiagnosis of dichromacy. Vision Res 2019; 158:135-145. [PMID: 30844384 DOI: 10.1016/j.visres.2019.02.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/13/2019] [Accepted: 02/17/2019] [Indexed: 11/26/2022]
Abstract
Retinal and cortical signals initiated by a single cone type can be recorded using the spectral compensation (or silent substitution) paradigm. Moreover, responses to instantaneous excitation increments combined with gradual excitation decreases are dominated by the response to the excitation increment. Similarly, the response to a sudden excitation decrement dominates the overall response when combined with a gradual excitation increase. Here ERGs and VEPs were recorded from 34 volunteers [25.9 ± 10.4 years old (mean ± 1 SD); 25 males, 9 females] to sawtooth flicker (4 Hz) stimuli that elicited L- or M-cone responses using triple silent substitution. The mean luminance (284 cd/m2) and the mean chromaticity (x = 0.5686, y = 0.3716; CIE 1931 color space) remained constant and thus the state of adaptation was the same in all conditions. Color discrimination thresholds along protan, deutan, and tritan axes were obtained from all participants. Dichromatic subjects were genetically characterized by molecular analysis of their opsin genes. ERG responses to L-cone stimuli were absent in protanopes whereas ERG responses to M-cone stimuli were strongly reduced in deuteranopes. Dichromats showed generally reduced VEP amplitudes. Responses to cone-specific stimuli obtained with standard electrophysiological methods may give the same classification as that obtained with the Cambridge Colour Test and in some cases with the genetic analysis of the L- and M-opsin genes. Therefore, cone-specific ERGs and VEPs may be reliable methods to detect cone dysfunction. The present data confirm and emphasize the potential use of cone-specific stimulation, combined with standard visual electrodiagnostic protocols.
Collapse
Affiliation(s)
- Mirella Telles Salgueiro Barboni
- Department of Experimental Psychology, University of Sao Paulo, Brazil; Department of Ophthalmology, Semmelweis University, Budapest, Hungary.
| | - Einat Hauzman
- Department of Experimental Psychology, University of Sao Paulo, Brazil; Instituto Israelita de Ensino e Pesquisa Albert Einstein, Sao Paulo, Brazil
| | - Balázs Vince Nagy
- Department of Experimental Psychology, University of Sao Paulo, Brazil; Department of Mechatronics, Optics and Engineering Informatics, Budapest University of Technology and Economics, Budapest, Hungary
| | | | - Avinash J Aher
- Department of Ophthalmology, University Hospital, Erlangen, Germany
| | - Tina I Tsai
- Department of Ophthalmology, University Hospital, Erlangen, Germany
| | - Daniela Maria Oliveria Bonci
- Department of Experimental Psychology, University of Sao Paulo, Brazil; Instituto Israelita de Ensino e Pesquisa Albert Einstein, Sao Paulo, Brazil
| | - Dora Fix Ventura
- Department of Experimental Psychology, University of Sao Paulo, Brazil; Instituto Israelita de Ensino e Pesquisa Albert Einstein, Sao Paulo, Brazil
| | - Jan Kremers
- Department of Ophthalmology, University Hospital, Erlangen, Germany; Department of Biology, Animal Physiology, FAU Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
The spatial structure of cone-opponent receptive fields in macaque retina. Vision Res 2018; 151:141-151. [DOI: 10.1016/j.visres.2017.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 05/23/2017] [Accepted: 05/30/2017] [Indexed: 11/24/2022]
|
15
|
Thwaites A, Wingfield C, Wieser E, Soltan A, Marslen-Wilson WD, Nimmo-Smith I. Entrainment to the CIECAM02 and CIELAB colour appearance models in the human cortex. Vision Res 2018; 145:1-10. [PMID: 29608936 DOI: 10.1016/j.visres.2018.01.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 01/25/2018] [Accepted: 01/30/2018] [Indexed: 11/30/2022]
Abstract
In human visual processing, information from the visual field passes through numerous transformations before perceptual attributes such as colour are derived. The sequence of transforms involved in constructing perceptions of colour can be approximated by colour appearance models such as the CIE (2002) colour appearance model, abbreviated as CIECAM02. In this study, we test the plausibility of CIECAM02 as a model of colour processing by looking for evidence of its cortical entrainment. The CIECAM02 model predicts that colour is split in to two opposing chromatic components, red-green and cyan-yellow (termed CIECAM02-a and CIECAM02-b respectively), and an achromatic component (termed CIECAM02-A). Entrainment of cortical activity to the outputs of these components was estimated using measurements of electro- and magnetoencephalographic (EMEG) activity, recorded while healthy subjects watched videos of dots changing colour. We find entrainment to chromatic component CIECAM02-a at approximately 35 ms latency bilaterally in occipital lobe regions, and entrainment to achromatic component CIECAM02-A at approximately 75 ms latency, also bilaterally in occipital regions. For comparison, transforms from a less physiologically plausible model (CIELAB) were also tested, with no significant entrainment found.
Collapse
Affiliation(s)
- Andrew Thwaites
- Department of Psychology, University of Cambridge, Cambridge, UK; MRC Cognition and Brain Sciences Unit, Cambridge, UK.
| | - Cai Wingfield
- Department of Psychology, University of Cambridge, Cambridge, UK; Department of Psychology, University of Lancaster, Lancaster, UK
| | - Eric Wieser
- Department of Engineering, University of Cambridge, Cambridge, UK
| | - Andrew Soltan
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - William D Marslen-Wilson
- Department of Psychology, University of Cambridge, Cambridge, UK; MRC Cognition and Brain Sciences Unit, Cambridge, UK
| | | |
Collapse
|
16
|
Nonselective Wiring Accounts for Red-Green Opponency in Midget Ganglion Cells of the Primate Retina. J Neurosci 2018; 38:1520-1540. [PMID: 29305531 DOI: 10.1523/jneurosci.1688-17.2017] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 12/17/2017] [Accepted: 12/21/2017] [Indexed: 11/21/2022] Open
Abstract
In primate retina, "red-green" color coding is initiated when signals originating in long (L) and middle (M) wavelength-sensitive cone photoreceptors interact antagonistically. The center-surround receptive field of "midget" ganglion cells provides the neural substrate for L versus M cone-opponent interaction, but the underlying circuitry remains unsettled, centering around the longstanding question of whether specialized cone wiring is present. To address this question, we measured the strength, sign, and spatial tuning of L- and M-cone input to midget receptive fields in the peripheral retina of macaque primates of either sex. Consistent with previous work, cone opponency arose when one of the cone types showed a stronger connection to the receptive field center than to the surround. We implemented a difference-of-Gaussians spatial receptive field model, incorporating known biology of the midget circuit, to test whether physiological responses we observed in real cells could be captured entirely by anatomical nonselectivity. When this model sampled nonselectively from a realistic cone mosaic, it accurately reproduced key features of a cone-opponent receptive field structure, and predicted both the variability and strength of cone opponency across the retina. The model introduced here is consistent with abundant anatomical evidence for nonselective wiring, explains both local and global properties of the midget population, and supports a role in their multiplexing of spatial and color information. It provides a neural basis for human chromatic sensitivity across the visual field, as well as the maintenance of normal color vision despite significant variability in the relative number of L and M cones across individuals.SIGNIFICANCE STATEMENT Red-green color vision is a hallmark of the human and nonhuman primate that starts in the retina with the presence of long (L)- and middle (M)-wavelength sensitive cone photoreceptor types. Understanding the underlying retinal mechanism for color opponency has focused on the broad question of whether this characteristic can emerge from nonselective wiring, or whether complex cone-type-specific wiring must be invoked. We provide experimental and modeling support for the hypothesis that nonselective connectivity is sufficient to produce the range of red-green color opponency observed in midget ganglion cells across the retina. Our nonselective model reproduces the diversity of physiological responses of midget cells while also accounting for systematic changes in color sensitivity across the visual field.
Collapse
|
17
|
Shevell SK, Martin PR. Color opponency: tutorial. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2017; 34:1099-1108. [PMID: 29036118 PMCID: PMC6022826 DOI: 10.1364/josaa.34.001099] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 05/03/2017] [Indexed: 05/20/2023]
Abstract
In dialogue, two color scientists introduce the topic of color opponency, as seen from the viewpoints of color appearance (psychophysics) and measurement of nerve cell responses (physiology). Points of difference as well as points of convergence between these viewpoints are explained. Key experiments from the psychophysical and physiological literature are covered in detail to help readers from these two broad fields understand each other's work.
Collapse
Affiliation(s)
- Steven K. Shevell
- Institute for Mind and Biology, The University of Chicago, 940 E. 57th St., Chicago, Illinois 60637, USA
- Department of Psychology, The University of Chicago, 940 E. 57th St., Chicago, Illinois 60637, USA
- Department of Ophthalmology & Visual Science, The University of Chicago, 940 E. 57th St., Chicago, Illinois 60637, USA
| | - Paul R. Martin
- Save Sight Institute, The University of Sydney Eye Hospital Campus, 8 Macquarie St., Sydney, NSW 2000, Australia
- Discipline of Physiology & School of Medical Sciences, The University of Sydney, NSW 2006, Australia
- Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney Eye Hospital Campus, 8 Macquarie St., Sydney, NSW 2000, Australia
| |
Collapse
|
18
|
Barrionuevo PA, Cao D. Luminance and chromatic signals interact differently with melanopsin activation to control the pupil light response. J Vis 2016; 16:29. [PMID: 27690169 PMCID: PMC5054726 DOI: 10.1167/16.11.29] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin. These cells receive afferent inputs from rods and cones, which provide inputs to the postreceptoral visual pathways. It is unknown, however, how melanopsin activation is integrated with postreceptoral signals to control the pupillary light reflex. This study reports human flicker pupillary responses measured using stimuli generated with a five-primary photostimulator that selectively modulated melanopsin, rod, S-, M-, and L-cone excitations in isolation, or in combination to produce postreceptoral signals. We first analyzed the light adaptation behavior of melanopsin activation and rod and cones signals. Second, we determined how melanopsin is integrated with postreceptoral signals by testing with cone luminance, chromatic blue-yellow, and chromatic red-green stimuli that were processed by magnocellular (MC), koniocellular (KC), and parvocellular (PC) pathways, respectively. A combined rod and melanopsin response was also measured. The relative phase of the postreceptoral signals was varied with respect to the melanopsin phase. The results showed that light adaptation behavior for all conditions was weaker than typical Weber adaptation. Melanopsin activation combined linearly with luminance, S-cone, and rod inputs, suggesting the locus of integration with MC and KC signals was retinal. The melanopsin contribution to phasic pupil responses was lower than luminance contributions, but much higher than S-cone contributions. Chromatic red-green modulation interacted with melanopsin activation nonlinearly as described by a “winner-takes-all” process, suggesting the integration with PC signals might be mediated by a postretinal site.
Collapse
Affiliation(s)
- Pablo A Barrionuevo
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USAInstitute of Research in Light, Environment and Vision, National University of Tucumán - National Scientific and Technical Research Council, San Miguel de Tucumán, Tucumán
| | - Dingcai Cao
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, ://vpl.uic.edu/
| |
Collapse
|
19
|
Schiller PH, Carvey CE. Demonstrations of Spatiotemporal Integration and what they Tell us about the Visual System. Perception 2016; 35:1521-55. [PMID: 17286122 DOI: 10.1068/p5564] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Five sets of displays are presented on the journal website to be viewed in conjunction with the text. We concentrate on the factors that give rise to the integration and disruption of the direction of apparent motion in two-dimensional and three-dimensional space. In the first set of displays we examine what factors contribute to the integration and disruption of apparent motion in the Ramachandran/Anstis clustered bistable quartets. In the second set we examine what factors give rise to the perception of the direction of motion in rotating two-dimensional wheels and dots. In the third and fourth sets we examine how the depth cues of shading and disparity contribute to the perception of apparent motion of opaque displays, and to the perception of rotating unoccluded displays, respectively. In the fifth set we examine how the depth cue of motion parallax influences the perception of apparent motion. Throughout, we make inferences about the roles which various parallel pathways and cortical areas play in the perceptions produced by the displays shown.
Collapse
Affiliation(s)
- Peter H Schiller
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | | |
Collapse
|
20
|
The spatial properties of L- and M-cone inputs to electroretinograms that reflect different types of post-receptoral processing. PLoS One 2015; 10:e0121218. [PMID: 25785459 PMCID: PMC4364754 DOI: 10.1371/journal.pone.0121218] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 01/29/2015] [Indexed: 11/22/2022] Open
Abstract
We studied the spatial arrangement of L- and M-cone driven electroretinograms (ERGs) reflecting the activity of magno- and parvocellular pathways. L- and M-cone isolating sine wave stimuli were created with a four primary LED stimulator using triple silent substitution paradigms. Temporal frequencies were 8 and 12 Hz, to reflect cone opponent activity, and 30, 36 and 48 Hz to reflect luminance activity. The responses were measured for full-field stimuli and for different circular and annular stimuli. The ERG data confirm the presence of two different mechanisms at intermediate and high temporal frequencies. The responses measured at high temporal frequencies strongly depended upon spatial stimulus configuration. In the full-field conditions, the L-cone driven responses were substantially larger than the full-field M-cone driven responses and also than the L-cone driven responses with smaller stimuli. The M-cone driven responses at full-field and with 70° diameter stimuli displayed similar amplitudes. The L- and M-cone driven responses measured at 8 and 12 Hz were of similar amplitude and approximately in counter-phase. The amplitudes were constant for most stimulus configurations. The results indicate that, when the ERG reflects luminance activity, it is positively correlated with stimulus size. Beyond 35° retinal eccentricity, the retina mainly contains L-cones. Small stimuli are sufficient to obtain maximal ERGs at low temporal frequencies where the ERGs are also sensitive to cone-opponent processing.
Collapse
|
21
|
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.
Collapse
|
22
|
Silveira LCL, Saito CA, da Silva Filho M, Kremers J, Bowmaker JK, Lee BB. Alouatta trichromatic color vision: cone spectra and physiological responses studied with microspectrophotometry and single unit retinal electrophysiology. PLoS One 2014; 9:e113321. [PMID: 25405863 PMCID: PMC4236167 DOI: 10.1371/journal.pone.0113321] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 10/27/2014] [Indexed: 11/18/2022] Open
Abstract
The howler monkeys (Alouatta sp.) are the only New World primates to exhibit routine trichromacy. Both males and females have three cone photopigments. However, in contrast to Old World monkeys, Alouatta has a locus control region upstream of each opsin gene on the X-chromosome and this might influence the retinal organization underlying its color vision. Post-mortem microspectrophotometry (MSP) was performed on the retinae of two male Alouatta to obtain rod and cone spectral sensitivities. The MSP data were consistent with only a single opsin being expressed in each cone and electrophysiological data were consistent with this primate expressing full trichromacy. To study the physiological organization of the retina underlying Alouatta trichromacy, we recorded from retinal ganglion cells of the same animals used for MSP measurements with a variety of achromatic and chromatic stimulus protocols. We found MC cells and PC cells in the Alouatta retina with similar properties to those previously found in the retina of other trichromatic primates. MC cells showed strong phasic responses to luminance changes and little response to chromatic pulses. PC cells showed strong tonic response to chromatic changes and small tonic response to luminance changes. Responses to other stimulus protocols (flicker photometry; changing the relative phase of red and green modulated lights; temporal modulation transfer functions) were also similar to those recorded in other trichromatic primates. MC cells also showed a pronounced frequency double response to chromatic modulation, and with luminance modulation response saturation accompanied by a phase advance between 10-20 Hz, characteristic of a contrast gain mechanism. This indicates a very similar retinal organization to Old-World monkeys. Cone-specific opsin expression in the presence of a locus control region for each opsin may call into question the hypothesis that this region exclusively controls opsin expression.
Collapse
Affiliation(s)
- Luiz Carlos L. Silveira
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil
- Núcleo de Medicina Tropical, Universidade Federal do Pará, Belém, Pará, Brazil
- * E-mail:
| | - Cézar A. Saito
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil
| | | | - Jan Kremers
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - James K. Bowmaker
- Division of Visual Science, Institute of Ophthalmology, University College London, London, England, United Kingdom
| | - Barry B. Lee
- State College of Optometry, State University of New York, New York, New York, United States of America
- Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| |
Collapse
|
23
|
Pietersen ANJ, Cheong SK, Solomon SG, Tailby C, Martin PR. Temporal response properties of koniocellular (blue-on and blue-off) cells in marmoset lateral geniculate nucleus. J Neurophysiol 2014; 112:1421-38. [DOI: 10.1152/jn.00077.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Visual perception requires integrating signals arriving at different times from parallel visual streams. For example, signals carried on the phasic-magnocellular (MC) pathway reach the cerebral cortex pathways some tens of milliseconds before signals traveling on the tonic-parvocellular (PC) pathway. Visual latencies of cells in the koniocellular (KC) pathway have not been specifically studied in simian primates. Here we compared MC and PC cells to “blue-on” (BON) and “blue-off” (BOF) KC cells; these cells carry visual signals originating in short-wavelength-sensitive (S) cones. We made extracellular recordings in the lateral geniculate nucleus (LGN) of anesthetized marmosets. We found that BON visual latencies are 10–20 ms longer than those of PC or MC cells. A small number of recorded BOF cells ( n = 7) had latencies 10–20 ms longer than those of BON cells. Within all cell groups, latencies of foveal receptive fields (<10° eccentricity) were longer (by 3–8 ms) than latencies of peripheral receptive fields (>10°). Latencies of yellow-off inputs to BON cells lagged the blue-on inputs by up to 30 ms, but no differences in visual latency were seen on comparing marmosets expressing dichromatic (“red-green color-blind”) or trichromatic color vision phenotype. We conclude that S-cone signals leaving the LGN on KC pathways are delayed with respect to signals traveling on PC and MC pathways. Cortical circuits serving color vision must therefore integrate across delays in (red-green) chromatic signals carried by PC cells and (blue-yellow) signals carried by KC cells.
Collapse
Affiliation(s)
- A. N. J. Pietersen
- Australian Research Council Centre of Excellence for Integrative Brain Function, University of Sydney, Sydney, Australia
- Save Sight Institute, University of Sydney, Sydney, Australia
| | - S. K. Cheong
- Australian Research Council Centre of Excellence for Integrative Brain Function, University of Sydney, Sydney, Australia
- Save Sight Institute, University of Sydney, Sydney, Australia
| | - S. G. Solomon
- School of Medical Sciences, University of Sydney, Sydney, Australia
- Department of Experimental Psychology, University College London, London, United Kingdom; and
| | - C. Tailby
- School of Medical Sciences, University of Sydney, Sydney, Australia
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia
| | - P. R. Martin
- Australian Research Council Centre of Excellence for Integrative Brain Function, University of Sydney, Sydney, Australia
- Save Sight Institute, University of Sydney, Sydney, Australia
- School of Medical Sciences, University of Sydney, Sydney, Australia
| |
Collapse
|
24
|
McKeefry D, Kremers J, Kommanapalli D, Challa NK, Murray IJ, Maguire J, Parry NRA. Incremental and decremental L- and M-cone-driven ERG responses: I. Square-wave pulse stimulation. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2014; 31:A159-A169. [PMID: 24695165 DOI: 10.1364/josaa.31.00a159] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Electroretinograms (ERGs) elicited by transient, square-wave L- and M-cone isolating stimuli were recorded from human trichromatic (n=19) and dichromatic (n=4) observers. The stimuli were generated on a four primary LED stimulator and were equated in terms of cone modulation (cone contrast=0.11) and retinal illuminance (12,000 trolands). L- and M-cone isolated ERGs had waveforms similar to those observed for luminance responses. However, M-cone ERGs exhibited a phase reversal in their responses to onset and offset stimuli relative to the L-cone responses. This on-off response reversal was observed in trichromats but not dichromats. Simultaneous counterphase and inphase combinations of L- and M-cone isolating stimuli generated responses that reflected chromatic and luminance processing, respectively. We conclude that L- and M-cone specific ERGs provide a measure of how photoreceptors contribute to postreceptoral mechanisms.
Collapse
|
25
|
Kommanapalli D, Murray IJ, Kremers J, Parry NRA, McKeefry DJ. Temporal characteristics of L- and M-cone isolating steady-state electroretinograms. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2014; 31:A113-A120. [PMID: 24695158 DOI: 10.1364/josaa.31.00a113] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Cone isolating stimuli were used to assess the temporal frequency response characteristics of L- and M-cone electroretinograms (ERGs) in nine trichromatic and four dichromatic human observers. The stimuli comprised sinusoidal temporal modulations varying from 5 to 100 Hz. ERGs were recorded using corneal fiber electrodes and subjected to fast Fourier transform analysis. At low temporal frequencies (<10 Hz) the L- and M-cone ERGs had similar amplitude and exhibited minimal differences in apparent latency. At higher flicker rates (>20 Hz) L-cone ERGs had greater amplitudes and shorter apparent latencies than the M-cone responses. These differences between the L- and M-cone ERGs are consistent with their mediation by chromatic and luminance postreceptoral processing pathways at low and high temporal frequencies, respectively.
Collapse
|
26
|
Abstract
The propagation of visual signals from individual cone photoreceptors through parallel neural circuits was examined in the primate retina. Targeted stimulation of individual cones was combined with simultaneous recording from multiple retinal ganglion cells of identified types. The visual signal initiated by an individual cone produced strong responses with different kinetics in three of the four numerically dominant ganglion cell types. The magnitude and kinetics of light responses in each ganglion cell varied nonlinearly with stimulus strength but in a manner that was independent of the cone of origin after accounting for the overall input strength of each cone. Based on this property of independence, the receptive field profile of an individual ganglion cell could be well estimated from responses to stimulation of each cone individually. Together, these findings provide a quantitative account of how elementary visual inputs form the ganglion cell receptive field.
Collapse
|
27
|
Barrionuevo PA, Nicandro N, McAnany JJ, Zele AJ, Gamlin P, Cao D. Assessing rod, cone, and melanopsin contributions to human pupil flicker responses. Invest Ophthalmol Vis Sci 2014; 55:719-27. [PMID: 24408974 DOI: 10.1167/iovs.13-13252] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We determined the relative contributions of rods, cones, and melanopsin to pupil responses in humans using temporal sinusoidal stimulation for light levels spanning the low mesopic to photopic range. METHODS A four-primary Ganzfeld photostimulator controlled flicker stimulations at seven light levels (-2.7 to 2 log cd/m(2)) and five frequencies (0.5-8 Hz). Pupil diameter was measured using a high-resolution eye tracker. Three kinds of sinusoidal photoreceptor modulations were generated using silent substitution: rod modulation, cone modulation, and combined rod and cone modulation in phase (experiment 1) or cone phase shifted (experiment 2) from a fixed rod phase. The melanopsin excitation was computed for each condition. A vector sum model was used to estimate the relative contribution of rods, cones, and melanopsin to the pupil response. RESULTS From experiment 1, the pupil frequency response peaked at 1 Hz at two mesopic light levels for the three modulation conditions. Analyzing the rod-cone phase difference for the combined modulations (experiment 2) identified a V-shaped response amplitude with a minimum between 135° and 180°. The pupil response phases increased as cone modulation phase increased. The pupil amplitude increased with increasing light level for cone, and combined (in-phase rod and cone) modulation, but not for the rod modulation. CONCLUSIONS These results demonstrate that cone- and rod-pathway contributions are more predominant than melanopsin contribution to the phasic pupil response. The combined rod, cone, and melanopsin inputs to the phasic state of the pupil light reflex follow linear summation.
Collapse
Affiliation(s)
- Pablo A Barrionuevo
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois
| | | | | | | | | | | |
Collapse
|
28
|
Li X, Chen Y, Lashgari R, Bereshpolova Y, Swadlow HA, Lee BB, Alonso JM. Mixing of Chromatic and Luminance Retinal Signals in Primate Area V1. Cereb Cortex 2014; 25:1920-37. [PMID: 24464943 DOI: 10.1093/cercor/bhu002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Vision emerges from activation of chromatic and achromatic retinal channels whose interaction in visual cortex is still poorly understood. To investigate this interaction, we recorded neuronal activity from retinal ganglion cells and V1 cortical cells in macaques and measured their visual responses to grating stimuli that had either luminance contrast (luminance grating), chromatic contrast (chromatic grating), or a combination of the two (compound grating). As with parvocellular or koniocellular retinal ganglion cells, some V1 cells responded mostly to the chromatic contrast of the compound grating. As with magnocellular retinal ganglion cells, other V1 cells responded mostly to the luminance contrast and generated a frequency-doubled response to equiluminant chromatic gratings. Unlike magnocellular and parvocellular retinal ganglion cells, V1 cells formed a unimodal distribution for luminance/color preference with a 2- to 4-fold bias toward luminance. V1 cells associated with positive local field potentials in deep layers showed the strongest combined responses to color and luminance and, as a population, V1 cells encoded a diverse combination of luminance/color edges that matched edge distributions of natural scenes. Taken together, these results suggest that the primary visual cortex combines magnocellular and parvocellular retinal inputs to increase cortical receptive field diversity and to optimize visual processing of our natural environment.
Collapse
Affiliation(s)
- Xiaobing Li
- Department of Biological Sciences, SUNY Optometry, New York, NY 10036, USA
| | - Yao Chen
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Reza Lashgari
- Department of Biological Sciences, SUNY Optometry, New York, NY 10036, USA Department of Biomedical Engineering, School of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran, Iran
| | - Yulia Bereshpolova
- Department of Psychology, University of Connecticut, Storrs, CT 06269, USA
| | - Harvey A Swadlow
- Department of Biological Sciences, SUNY Optometry, New York, NY 10036, USA Department of Psychology, University of Connecticut, Storrs, CT 06269, USA
| | - Barry B Lee
- Department of Biological Sciences, SUNY Optometry, New York, NY 10036, USA Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Jose Manuel Alonso
- Department of Biological Sciences, SUNY Optometry, New York, NY 10036, USA Department of Psychology, University of Connecticut, Storrs, CT 06269, USA
| |
Collapse
|
29
|
On using isoluminant stimuli to separate magno- and parvocellular responses in psychophysical experiments-a few words of caution. Behav Res Methods 2013; 45:637-45. [PMID: 23292567 DOI: 10.3758/s13428-012-0290-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Isoluminant (or equiluminant) color stimuli (i.e., those that contain variations only in chromaticity) have been employed in attempts to separate magno- and parvocellular responses in psychophysical and noninvasive electrophysiological experiments. The justification for this has been the assumption that magnocellular cells, unlike parvocellular neurons, do not respond to stimuli varying only in hue. However, several problems are associated with this notion: (1) under many conditions, magnocellular neurons are not fully silenced at isoluminance, and (2) in many circumstances, parvocellular responses are substantially reduced at isoluminance. To rely upon isoluminant stimuli to "bias" stimuli toward the parvocellular system also faces obstacles. Therefore, caution is required when attempting to use isoluminant color to separate magno- and parvocellular responses.
Collapse
|
30
|
Gowrisankaran S, Alexander KR. Stimulus chromatic properties affect period doubling in the human cone flicker ERG. Doc Ophthalmol 2012; 125:21-9. [PMID: 22581377 DOI: 10.1007/s10633-012-9326-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 04/16/2012] [Indexed: 11/29/2022]
Abstract
Period doubling in the full-field cone flicker electroretinogram (ERG) refers to an alternation in waveform amplitude and/or shape from cycle to cycle, presumably owing to the operation of a nonlinear gain control mechanism. This study examined the influence of stimulus chromatic properties on the characteristics of period doubling in order to better understand the underlying mechanism. ERGs were acquired from 5 visually normal subjects in response to sinusoidally modulated flicker presented at frequencies from 25 to 100 Hz. The test stimuli and the pre-stimulus adaptation were either long wavelength (R), middle wavelength (G), or an equal combination of long and middle wavelengths (Y), all equated for photopic luminance. Fourier analysis was used to obtain the response amplitude at the stimulus frequency F and at a harmonic frequency of 3F/2, which was used as the index of period doubling. The frequency-response function for 3F/2 typically showed two peaks, occurring at approximately 33.3 and 50 Hz. However, the magnitude of period doubling within these frequency regions was dependent on the chromatic properties of both the test stimulus and the pre-stimulus adaptation. Period doubling was generally smallest when an R test was used, even though the stimuli were luminance-equated and the amplitude of F did not differ between the various conditions. The pattern of results indicates that the mechanism that generates period doubling is influenced by chromatic signals from both the test stimulus and the pre-stimulus adaptation, even though the high stimulus frequencies presumably favor the achromatic luminance system.
Collapse
Affiliation(s)
- Sowjanya Gowrisankaran
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1855 W. Taylor St, Chicago, IL 60612, USA
| | | |
Collapse
|
31
|
Sun H, Cooper B, Lee BB. Luminance and chromatic contributions to a hyperacuity task: isolation by contrast polarity and target separation. Vision Res 2012; 56:28-37. [PMID: 22306680 DOI: 10.1016/j.visres.2012.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 01/06/2012] [Accepted: 01/07/2012] [Indexed: 10/14/2022]
Abstract
Vernier thresholds are known to be elevated when a target pair has opposite contrast polarity. Polarity reversal is used to assess the role of luminance and chromatic pathways in hyperacuity performance. Psychophysical hyperacuity thresholds were measured for pairs of gratings of various combinations of luminance (Lum) and chromatic (Chr) contrast polarities, at different ratios of luminance to chromatic contrast. With two red-green gratings of matched luminance and chromatic polarity (+Lum+Chr), there was an elevation of threshold at isoluminance. When both luminance and chromatic polarity were mismatched (-Lum-Chr), thresholds were substantially elevated under all conditions. With the same luminance contrast polarity and opposite chromatic polarity (+Lum-Chr) thresholds were only elevated close to isoluminance; in the reverse condition (-Lum+Chr), thresholds were elevated as in the -Lum-Chr condition except close to equiluminance. Similar data were obtained for gratings isolating the short-wavelength cone mechanism. Further psychophysical measurements assessed the role of target separation with matched or mismatched contrast polarity; similar results were found for luminance and chromatic gratings. Comparison physiological data were collected from parafoveal ganglion cells of the macaque retina. Positional precision of ganglion cell signals was assessed under conditions related to the psychophysical measurements. On the basis of these combined observations, it is argued that both magnocellular, parvocellular, and koniocellular pathways have access to cortical positional mechanisms associated with vernier acuity.
Collapse
Affiliation(s)
- Hao Sun
- State University of New York, State College of Optometry, NY, USA
| | | | | |
Collapse
|
32
|
Cao D, Lu YH. Chromatic discrimination: differential contributions from two adapting fields. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2012; 29:A1-9. [PMID: 22330364 PMCID: PMC3319031 DOI: 10.1364/josaa.29.0000a1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
To test whether a retinal or cortical mechanism sums contributions from two adapting fields to chromatic discrimination, L/M discrimination was measured with a test annulus surrounded by an inner circular field and an outer rectangular field. A retinal summation mechanism predicted that the discrimination pattern would not change with a change in the fixation location. Therefore, the fixation was set either in the inner or the outer field in two experiments. When one of the adapting fields was "red" and the other was "green," the adapting field where the observer fixated always had a stronger influence on chromatic discrimination. However, when one adapting field was "white" and the other was red or green, the white field always weighted more heavily than the other adapting field in determining discrimination thresholds, whether the white field or the fixation was in the inner or outer adapting field. These results suggest that a cortical mechanism determines the relative contributions from different adapting fields.
Collapse
Affiliation(s)
- Dingcai Cao
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1905 West Taylor Street, Room 149, Chicago, Illinois 60615, USA.
| | | |
Collapse
|
33
|
Zele AJ, Kremers J, Feigl B. Mesopic rod and S-cone interactions revealed by modulation thresholds. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2012; 29:A19-A26. [PMID: 22330378 DOI: 10.1364/josaa.29.000a19] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We analyzed mesopic rod and S-cone interactions in terms of their contributions to the blue-yellow opponent pathway. Stimuli were generated using a four-primary colorimeter. Mixed rod and S-cone modulation thresholds (constant L-, M-cone excitation) were measured as a function of their phase difference. Modulation amplitude was equated using threshold units and contrast ratios. This study identified three interaction types: (1) a linear and antagonistic rod:S-cone interaction, (2) probability summation, and (3) a previously unidentified mutual nonlinear reinforcement. Linear rod:S-cone interactions occur within the blue-yellow opponent pathway. Probability summation involves signaling by different postreceptoral pathways. The origin of the nonlinear reinforcement is possibly at the photoreceptors.
Collapse
Affiliation(s)
- Andrew J Zele
- Visual Science Laboratory, School of Optometry and Vision Science & Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia.
| | | | | |
Collapse
|
34
|
Cao D, Zele AJ, Pokorny J, Lee DY, Messner LV, Diehl C, Ksiazek S. Functional loss in the magnocellular and parvocellular pathways in patients with optic neuritis. Invest Ophthalmol Vis Sci 2011; 52:8900-7. [PMID: 22016061 DOI: 10.1167/iovs.11-7644] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate contrast threshold and contrast gain in patients with optic neuritis under conditions designed to favor mediation by either the inferred magnocellular (MC) or parvocellular (PC) pathway. METHODS Achromatic and chromatic contrast discrimination was measured in 11 patients with unilateral or bilateral optic neuritis and in 18 age-matched controls with normal vision, using achromatic steady- and pulsed-pedestal paradigms to bias performance toward the MC or PC pathway, respectively. In addition, L-M chromatic discrimination at equiluminance was evaluated using the steady-pedestal paradigm. A physiologically plausible model could describe the data with parameters accounting for contrast gain and contrast sensitivity in the inferred MC or PC pathway. The fitted parameters from the eye affected by optic neuritis were compared with those from the normal eye using generalized estimation equation (GEE) models that can account for within-subject correlations. RESULTS Compared with normal eyes, the affected eyes had significantly higher saturation parameters when measured with both the achromatic pulsed-pedestal paradigm (GEE: β [SE] = 0.35 [0.06]; P < 0.001) and the chromatic discrimination paradigm (β [SE] = 0.18 [0.08]; P = 0.015), suggesting that contrast gain in the inferred PC pathway is reduced; the affected eyes also had reduced absolute sensitivity in the inferred MC pathway measured with the achromatic steady-pedestal paradigm (β [SE] = 0.12 [0.04]; P = 0.005). CONCLUSIONS Optic neuritis produced large sensitivity losses mediated by the MC pathway and contrast gain losses in the inferred PC pathway. A clinical framework is presented for interpreting contrast sensitivity and gain loss to chromatic and achromatic stimuli in terms of retinal and postretinogeniculate loci contributions to detection and discrimination.
Collapse
Affiliation(s)
- Dingcai Cao
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1905 W.Taylor Street, Room 149, Chicago, IL 60615, USA.
| | | | | | | | | | | | | |
Collapse
|
35
|
Martin PR, Blessing EM, Buzás P, Szmajda BA, Forte JD. Transmission of colour and acuity signals by parvocellular cells in marmoset monkeys. J Physiol 2011; 589:2795-812. [PMID: 21486786 DOI: 10.1113/jphysiol.2010.194076] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The red-green axis of colour vision evolved recently in primate evolutionary history. Signals serving red-green colour vision travel together with signals serving spatial vision, in the parvocellular (PC) division of the subcortical visual pathway. However, the question of whether receptive fields of PC pathway cells are specialized to transmit red-green colour signals remains unresolved. We addressed this question in single-cell recordings from the lateral geniculate nucleus of anaesthetized marmosets. Marmosets show a high proportion of dichromatic (red-green colour-blind) individuals, allowing spatial and colour tuning properties of PC cells to be directly compared in dichromatic and trichromatic visual systems. We measured spatial frequency tuning for sine gratings that provided selective stimulation of individual photoreceptor types. We found that in trichromatic marmosets, the foveal visual field representation is dominated by red-green colour-selective PC cells. Colour selectivity of PC cells is reduced at greater eccentricities, but cone inputs to centre and surround are biased to create more selectivity than predicted by a purely 'random wiring' model. Thus, one-to-one connections in the fovea are sufficient, but not necessary, to create colour-selective responses. The distribution of spatial tuning properties for achromatic stimuli shows almost complete overlap between PC cells recorded in dichromatic and trichromatic marmosets. These data indicate that transmission of red-green colour signals has been enabled by centre-surround receptive fields of PC cells, and has not altered the capacity of PC cells to serve high-acuity vision at high stimulus contrast.
Collapse
Affiliation(s)
- Paul R Martin
- Department of Ophthalmology and Save Sight Institute, University of Sydney Eye Hospital Campus, GPO Box 4337, Sydney, NSW 2001, Australia.
| | | | | | | | | |
Collapse
|
36
|
Abstract
The general principles of retinal organization are now well known. It may seem surprising that retinal organization in the primate, which has a complex visual behavioral repertoire, appears relatively simple. In this review, we primarily consider retinal structure and function in primate species. Photoreceptor distribution and connectivity are considered as are connectivity in the outer and inner retina. One key issue is the specificity of retinal connections; we suggest that the retina shows connectional specificity but this is seldom complete, and we consider here the functional consequences of imprecise wiring. Finally, we consider how retinal systems can be linked to psychophysical descriptions of different channels, chromatic and luminance, which are proposed to exist in the primate visual system.
Collapse
Affiliation(s)
- Barry B Lee
- SUNY College of Optometry, New York 10036, USA.
| | | | | |
Collapse
|
37
|
Lee BB, Sun H, Cao D. Macaque ganglion cell responses to probe stimuli on modulated backgrounds. J Vis 2010; 10:26. [PMID: 21047758 PMCID: PMC2983472 DOI: 10.1167/10.12.26] [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] [Indexed: 11/24/2022] Open
Abstract
In the natural environment, visual targets have to be detected and identified on changing backgrounds. Here, responses of parasol (magnocellular) ganglion cells to probes on modulated backgrounds are described. At low frequency, the adaptation level of the background influences the probe response, but with increasing frequency there is a strong interaction with the response to the background per se, so that on- and off-center cell responses are modulated in different phases. Interactions with the background response include both thresholding effects (when the cell's firing is suppressed and no pulse response occurs) and saturation effects (when the background response is vigorous the pulse generates few additional spikes). At 30 Hz, the effect of the pulse is largely a suppression or phase shift of the background response. The data are relevant to the probed-sinewave paradigm, in which pulse detection thresholds are modulated with pulse phase relative to a sinusoidal background. The physiological substrates of the psychophysical results with the probed-sinewave paradigm appear complex, with on- and off-center cells likely to contribute to detection at different pulse phases.
Collapse
Affiliation(s)
- Barry B. Lee
- SUNY College of Optometry, New York, NY, USA, & Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Hao Sun
- Department of Optometry and Visual Sciences, Buskerud University College, Kongsberg, Norway
| | - Dingcai Cao
- Sections of Surgical Research and Ophthalmology and Visual Science, Department of Surgery, University of Chicago, Chicago, IL, USA
| |
Collapse
|
38
|
Lee BB, Sun H, Valberg A. Segregation of chromatic and luminance signals using a novel grating stimulus. J Physiol 2010; 589:59-73. [PMID: 20937716 DOI: 10.1113/jphysiol.2010.188862] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Segregation of chromatic and luminance signals in afferent pathways are investigated with a grating stimulus containing luminance and chromatic components of different spatial frequencies. Ganglion cell recordings were obtained from the retinae of macaques (Macaca fascicularis). Cell responses to the 'compound' gratings were compared to responses to standard chromatic and luminance gratings. Parvocellular (PC) pathway cell responses to compound and chromatic gratings were very similar, as were magnocellular (MC) cell responses to compound and luminance gratings. This was the case over a broad range of spatial and temporal frequencies and contrasts. In psychophysical experiments with human observers, discrimination between grating types was possible close to detection threshold. These results are consistent with chromatic and luminance structure in complex patterns being strictly localized in different afferent pathways. This novel stimulus may prove useful in identifying afferent inputs to cortical neurons.
Collapse
Affiliation(s)
- Barry B Lee
- SUNY Optometry, 33 W. 42nd St, New York, NY 10036, USA.
| | | | | |
Collapse
|
39
|
Cao D, Lee BB, Sun H. Combination of rod and cone inputs in parasol ganglion cells of the magnocellular pathway. J Vis 2010; 10:4. [PMID: 20884499 DOI: 10.1167/10.11.4] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
This study investigates how rod and cone inputs are combined in the magnocellular (MC) pathway in the mesopic luminance range, when both rods and cones are active. Responses of parafoveal MC ganglion cells from macaque retina were measured as a function of temporal frequency (0.62-20 Hz) or contrast (0.05-0.55) at mesopic light levels (0.2, 2, 20, and 200 td). Stimuli were of three modulation types: (1) isolated rod stimuli (only rod signals were modulated), (2) isolated cone stimuli (only cone luminance signals from long- and middle-wavelength sensitive cones were modulated), and (3) combined rod and cone stimuli (both rod and cone luminance signals were modulated in phase, as with conventional stimuli). The results showed that under mesopic conditions, the relative rod and cone inputs to the MC cells varied with light level and they are combined linearly prior to saturation. Further, rod contrast gain is relatively stable over the mesopic range while cone contrast gain increased with light level. Finally, the measured rod and cone inputs are consistent with the measured human temporal contrast sensitivity functions under comparable stimulation conditions.
Collapse
Affiliation(s)
- Dingcai Cao
- Sections of Surgical Research and Ophthalmology and Visual Science, Department of Surgery, University of Chicago, Chicago, IL, USA.
| | | | | |
Collapse
|
40
|
Parallel ON and OFF cone bipolar inputs establish spatially coextensive receptive field structure of blue-yellow ganglion cells in primate retina. J Neurosci 2009; 29:8372-87. [PMID: 19571128 DOI: 10.1523/jneurosci.1218-09.2009] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the primate retina the small bistratified, "blue-yellow" color-opponent ganglion cell receives parallel ON-depolarizing and OFF-hyperpolarizing inputs from short (S)-wavelength sensitive and combined long (L)- and middle (M)-wavelength sensitive cone photoreceptors, respectively. However, the synaptic pathways that create S versus LM cone-opponent receptive field structure remain controversial. Here, we show in the macaque monkey retina in vitro that at photopic light levels, when an identified rod input is excluded, the small bistratified cell displays a spatially coextensive receptive field in which the S-ON-input is in spatial, temporal, and chromatic balance with the LM-OFF-input. ON pathway block with l-AP-4, the mGluR6 receptor agonist, abolished the S-ON response but spared the LM-OFF response. The isolated LM component showed a center-surround receptive field structure consistent with an input from OFF-center, ON-surround "diffuse" cone bipolar cells. Increasing retinal buffering capacity with HEPES attenuated the LM-ON surround component, consistent with a non-GABAergic outer retina feedback mechanism for the bipolar surround. The GABAa/c receptor antagonist picrotoxin and the glycine receptor antagonist strychnine did not affect chromatic balance or the basic coextensive receptive field structure, suggesting that the LM-OFF field is not generated by an inner retinal inhibitory pathway. We conclude that the opponent S-ON and LM-OFF responses originate from the excitatory receptive field centers of S-ON and LM-OFF cone bipolar cells, and that the LM-OFF- and ON-surrounds of these parallel bipolar inputs largely cancel, explaining the small, spatially coextensive but spectrally antagonistic receptive field structure of the blue-ON ganglion cell.
Collapse
|
41
|
Skottun BC, Skoyles JR. Visual Search: Magno- and Parvocellular Systems or Color and Luminance Processes? Int J Neurosci 2009; 118:1259-67. [DOI: 10.1080/00207450701239434] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
42
|
Lee BB, Sun H. The chromatic input to cells of the magnocellular pathway of primates. J Vis 2009; 9:15.1-18. [PMID: 19271925 DOI: 10.1167/9.2.15] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 12/15/2008] [Indexed: 11/24/2022] Open
Abstract
Parasol ganglion cells of the magnocellular (MC) pathway form the physiological substrate of a luminance channel underlying photometric tasks, but they also respond weakly to red-green chromatic modulation. This may take the form of a first-harmonic (1F) response to chromatic modulation at low temporal frequencies, and/or a second-harmonic (2F) response that is more marked at higher frequencies. It is shown here that both these responses originate from a receptive field component that is intermediate in size between center and surround, i.e., a discrete, chromatic receptive field is superimposed upon an achromatic center-surround structure. Its size is similar to the receptive field (center plus surround) of midget, parvocellular cells from the same retinal eccentricity. A 2F MC cell chromatic response component is shown to be present under cone silent substitution conditions, when only the middle- (M) or long-wavelength (L) cone is modulated. This and other features suggest it is a rectified response to a chromatic signal rather than a consequence of non-linear summation of M- and L-cone signals. A scheme is presented which could give rise to such responses. It is suggested that this chromatic input to MC cells can enhance motion signals to red-green borders close to equiluminance.
Collapse
Affiliation(s)
- Barry B Lee
- SUNY College of Optometry, New York, NY 10036, USA.
| | | |
Collapse
|
43
|
Abstract
In the natural environment, color discriminations are made within a rich context of spatial and temporal variation. In classical laboratory methods for studying chromatic discrimination, there is typically a border between the test and adapting fields that introduces a spatial chromatic contrast signal. Typically, the roles of spatial and temporal contrast on chromatic discrimination are not assessed in the laboratory approach. In this study, S-cone discrimination was measured using stimulus paradigms that controlled the level of spatio-temporal S-cone contrast between the tests and adapting fields. The results indicate that S-cone discrimination of chromaticity differences between a pedestal and adapting surround is equivalent for stimuli containing spatial, temporal or spatial-and-temporal chromatic contrast between the test field and the surround. For a stimulus condition that did not contain spatial or temporal contrast, the visual system adapted to the pedestal instead of the surround. The data are interpreted in terms of a model consistent with primate koniocellular pathway physiology. The paradigms provide an approach for studying the effects of spatial and temporal contrast on discrimination in natural scenes.
Collapse
|
44
|
Hashemi-Nezhad M, Blessing EM, Dreher B, Martin PR. Segregation of short-wavelength sensitive (“blue”) cone signals among neurons in the lateral geniculate nucleus and striate cortex of marmosets. Vision Res 2008; 48:2604-14. [DOI: 10.1016/j.visres.2008.02.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Revised: 02/14/2008] [Accepted: 02/15/2008] [Indexed: 11/25/2022]
|
45
|
Smith VC, Pokorny J, Lee BB, Dacey DM. Sequential processing in vision: The interaction of sensitivity regulation and temporal dynamics. Vision Res 2008; 48:2649-56. [PMID: 18558416 PMCID: PMC2627776 DOI: 10.1016/j.visres.2008.05.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Revised: 04/21/2008] [Accepted: 05/05/2008] [Indexed: 10/21/2022]
Abstract
The goal of this work was to describe the interaction of sensitivity regulation and temporal dynamics through the primate retina. A linear systems model was used to describe the temporal amplitude sensitivity at different retinal illuminances. Predictions for the primate H1 horizontal cell were taken as the starting point. The H1 model incorporated an early time-dependent stage of sensitivity regulation by the cones. It was adjusted to reduce the effects of gap junction input and then applied as input to a model describing temporal amplitude sensitivity of Parvocellular and Magnocellular pathway retinal ganglion cells. The ganglion cell model incorporated center-surround subtraction. The H1 based model required little modification to describe the Parvocellular data. The Magnocellular data required a further time-dependent stage of sensitivity regulation that resulted in Weber's Law. Psychophysical data reflect the sensitivity regulation of the retinal ganglion cell pathways but show a decline in temporal resolution that is most pronounced for the post-retinal processing of Parvocellular signals.
Collapse
Affiliation(s)
- Vivianne C. Smith
- The University of Chicago, Opthalmology and Visual Science, 940 East 57th Street, Chicago, IL 60637, USA
| | - Joel Pokorny
- The University of Chicago, Opthalmology and Visual Science, 940 East 57th Street, Chicago, IL 60637, USA
| | - Barry B. Lee
- State University of New York College of Optometry, NY, USA
- The Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | | |
Collapse
|
46
|
Cao D, Pokorny J, Smith VC, Zele AJ. Rod contributions to color perception: linear with rod contrast. Vision Res 2008; 48:2586-92. [PMID: 18561973 DOI: 10.1016/j.visres.2008.05.001] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 04/25/2008] [Accepted: 05/01/2008] [Indexed: 11/29/2022]
Abstract
At mesopic light levels, an incremental change in rod activation causes changes in color appearance. In this study, we investigated how rod mediated changes in color perception varied as a function of the magnitude of the rod contrast. Rod-mediated changes in color appearance were assessed by matching them with cone-mediated color changes. A two-channel four-primary colorimeter allowed independent control of the rods and each of the L-, M- and S-cone photoreceptor types. At all light levels, rod contributions to inferred PC, KC and MC pathway mediated vision were linearly related to the rod incremental contrast. This linear relationship could be described by a model based on primate ganglion cell responses with the assumption that rod signals were conveyed via rod-cone gap junctions at mesopic light levels.
Collapse
Affiliation(s)
- Dingcai Cao
- Department of Ophthalmology & Visual Science, University of Chicago, 940 East 57th Street, Chicago, IL 60637, USA.
| | | | | | | |
Collapse
|
47
|
Abstract
In the lateral geniculate nucleus of macaque, we recorded from neurons with substantial input from S-cones and found that, on several important dimensions, the properties of neurons that receive inhibitory input from S-cones ("S-") are quite unlike those of neurons that receive excitatory input from S-cones ("S+"). First, the organization of chromatic inputs differs substantially: in S+ cells, S-cone signals were usually opposed by those of L- and M-cones; in S- cells, signals from L-cones were usually opposed to those of S- and M-cones. Second, to pure S-cone modulation, S+ cells are twice as sensitive as S- cells, but S- cells were much more susceptible to contrast adaptation. Third, in S- cells but not S+ cells, the spatial frequency resolution for achromatic modulation was often greater, the tuning curve and more bandpass, than that for S-cone modulation. Along the dimensions on which we measured, the properties of the S+ cells were relatively tightly clustered, suggesting a homogenous class. Although the chromatic properties of S- cells are heterogeneous, the distribution of their tuning along other stimulus dimensions does not suggest multiple subtypes.
Collapse
|
48
|
Lee BB, Smith VC, Pokorny J, Sun H. Chromatic adaptation in red-green cone-opponent retinal ganglion cells of the macaque. Vision Res 2008; 48:2625-32. [PMID: 18281074 DOI: 10.1016/j.visres.2008.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 12/23/2007] [Accepted: 01/05/2008] [Indexed: 11/27/2022]
Abstract
The degree of chromatic adaptation of midget ganglion cells of the parvocellular (PC) pathway was studied by measuring long-(L) to middle-wavelength (M) cone weighting at different mean chromaticities in the mid-photopic range. Cone weighting was measured using a protocol involving changing the relative phase of modulated lights, which provided an estimate independent of the level of maintained activity. The degree of adaptation at 2500 td was found to be less than complete (i.e., sub-Weberian), with the M- and L-cone contributions having slopes averaging 0.89 rather than 1.0. This is broadly consistent with the degree of light adaptation present in this cell class. The changes in maintained activity following a step change in chromaticity took tens of seconds to return toward a baseline level, but changes in cone weighting appeared much faster.
Collapse
Affiliation(s)
- Barry B Lee
- State University of New York, State College of Optometry, 33 W42nd Street, New York, NY, USA.
| | | | | | | |
Collapse
|
49
|
Lee BB, Sun H, Zucchini W. The temporal properties of the response of macaque ganglion cells and central mechanisms of flicker detection. J Vis 2007; 7:1.1-16. [PMID: 18217796 DOI: 10.1167/7.14.1] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Accepted: 06/22/2007] [Indexed: 11/24/2022] Open
Abstract
This analysis assesses sensitivity of primate ganglion cells to sinusoidal modulation as a function of temporal frequency, based on the structure of their impulse trains; sensitivity to luminance and chromatic modulation was compared to human psychophysical sensitivity to similar stimuli. Each stimulus cycle was Fourier analyzed, and response amplitudes subjected to neurometric analysis; this assumes a detector with duration inversely proportional to frequency, that is, the stimulus epoch analyzed is a single cycle rather than a fixed duration, and provides an upper bound for a detection by an observer who bases judgments on a single cell. Signal-to-noise ratio for a given Fourier amplitude rapidly decreased with temporal frequency. This is a consequence of the statistics of impulse trains making up the response; at higher temporal frequencies, there are fewer impulses per cycle. Performance of this "single-cell" observer was then compared with that of modeled central detection mechanisms of fixed duration. For chromatic modulation, a filter/detector with a time constant of approximately 40 ms operating upon the parvocellular (PC) pathway provided a match to psychophysical results, whereas for luminance modulation, a filter/detection mechanism operating upon the magnocellular (MC) pathway with a time constant of approximately 5-10 ms provided a suitable match. The effects of summation and nonlinear interactions between cell inputs to detection are also considered in terms of enhanced sensitivity and "sharpness" of thresholds, that is, the steepness of the neurometric function. For both luminance (MC cells) and chromatic modulation (PC cells), restricted convergence (<20 cells) appears adequate to provide sharp thresholds and sensitivity comparable to psychophysical performance.
Collapse
Affiliation(s)
- Barry B Lee
- SUNY College of Optometry, New York, NY 10036, USA.
| | | | | |
Collapse
|
50
|
Kilavik BE, Silveira LCL, Kremers J. Spatial receptive field properties of lateral geniculate cells in the owl monkey (Aotus azarae) at different contrasts: a comparative study. Eur J Neurosci 2007; 26:992-1006. [PMID: 17714192 DOI: 10.1111/j.1460-9568.2007.05709.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Several physiological properties of owl monkey lateral geniculate nucleus (LGN) cells were studied to verify whether its nocturnal habit has an influence on the organization of its subcortical visual system. Receptive field (RF) dimensions were measured using drifting gratings and bipartite field stimuli. We found that owl monkey cells LGN have larger RFs and were on average more non-linear than those of diurnal monkeys. But, as in other anthropoids, there is an increase in RF centre size with increasing eccentricity, and there is a limited correlation between these centre sizes and retinal ganglion cell dendritic tree sizes. The influence of contrast on sizes and peak sensitivities of RF centres and surrounds and on the response phases was studied. Both the sizes and peak sensitivities of the RF centres and surrounds decrease as contrast increases. As a result, the responses to low spatial frequency stimuli saturate with increasing contrast. Estimates of contrasts at half-maximal responses confirm the presence of saturation. It was found that the magnocellular cells saturate more strongly than parvocellular cells. The response phase increases with increasing contrast. These data resemble those obtained in the common marmoset, indicating that these are basic features of the primate visual system. We conclude that during evolution and as an adaptation to a nocturnal lifestyle, cells in the owl monkey LGN display an increased spatial integration in comparison with diurnal primate species, without a change in the basic organization common to the primate subcortical visual system.
Collapse
Affiliation(s)
- B E Kilavik
- Department of Experimental Ophthalmology, University of Tübingen Eye Hospital, Röntgenweg 11, D-72076 Tübingen, Germany
| | | | | |
Collapse
|