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Lee SCS, Wei AJ, Martin PR, Grünert U. Thorny and Tufted Retinal Ganglion Cells Express the Transcription Factor Forkhead Proteins Foxp1 and Foxp2 in Marmoset (Callithrix jacchus). J Comp Neurol 2024; 532:e25663. [PMID: 39235164 DOI: 10.1002/cne.25663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 07/25/2024] [Accepted: 08/06/2024] [Indexed: 09/06/2024]
Abstract
The transcription factor forkhead/winged-helix domain proteins Foxp1 and Foxp2 have previously been studied in mouse retina, where they are expressed in retinal ganglion cells named F-mini and F-midi. Here we show that both transcription factors are expressed by small subpopulations (on average less than 10%) of retinal ganglion cells in the retina of the marmoset monkey (Callithrix jacchus). The morphology of Foxp1- and Foxp2-expressing cells was revealed by intracellular DiI injections of immunofluorescent cells. Foxp1- and Foxp2-expressing cells comprised multiple types of wide-field ganglion cells, including broad thorny cells, narrow thorny cells, and tufted cells. The large majority of Foxp2-expressing cells were identified as tufted cells. Tufted cells stratify broadly in the middle of the inner plexiform layer. They resemble broad thorny cells but their proximal dendrites are bare of branches and the distal dendrites branch frequently forming dense dendritic tufts. Double labeling with calretinin, a previously established marker for broad thorny and narrow thorny cells, showed that only a small proportion of ganglion cells co-expressed calretinin and Foxp1 or Foxp2 supporting the idea that the two markers are differentially expressed in retinal ganglion cells of marmoset retina.
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Affiliation(s)
- Sammy C S Lee
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Anlai J Wei
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Paul R Martin
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Ulrike Grünert
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
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2
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Kilpeläinen M, Westö J, Tiihonen J, Laihi A, Takeshita D, Rieke F, Ala-Laurila P. Primate retina trades single-photon detection for high-fidelity contrast encoding. Nat Commun 2024; 15:4501. [PMID: 38802354 PMCID: PMC11130139 DOI: 10.1038/s41467-024-48750-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 05/10/2024] [Indexed: 05/29/2024] Open
Abstract
How the spike output of the retina enables human visual perception is not fully understood. Here, we address this at the sensitivity limit of vision by correlating human visual perception with the spike outputs of primate ON and OFF parasol (magnocellular) retinal ganglion cells in tightly matching stimulus conditions. We show that human vision at its ultimate sensitivity limit depends on the spike output of the ON but not the OFF retinal pathway. Consequently, nonlinear signal processing in the retinal ON pathway precludes perceptual detection of single photons in darkness but enables quantal-resolution discrimination of differences in light intensity.
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Affiliation(s)
- Markku Kilpeläinen
- Department of Psychology and Logopedics, University of Helsinki, Helsinki, Finland
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
| | - Johan Westö
- Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland
| | - Jussi Tiihonen
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
- Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland
| | - Anton Laihi
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
| | - Daisuke Takeshita
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
| | - Fred Rieke
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, US
| | - Petri Ala-Laurila
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland.
- Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland.
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3
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Ryu J, Lee SH. Bounded contribution of human early visual cortex to the topographic anisotropy in spatial extent perception. Commun Biol 2024; 7:178. [PMID: 38351283 PMCID: PMC10864322 DOI: 10.1038/s42003-024-05846-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 01/23/2024] [Indexed: 02/16/2024] Open
Abstract
To interact successfully with objects, it is crucial to accurately perceive their spatial extent, an enclosed region they occupy in space. Although the topographic representation of space in the early visual cortex (EVC) has been favored as a neural correlate of spatial extent perception, its exact nature and contribution to perception remain unclear. Here, we inspect the topographic representations of human individuals' EVC and perception in terms of how much their anisotropy is influenced by the orientation (co-axiality) and radial position (radiality) of stimuli. We report that while the anisotropy is influenced by both factors, its direction is primarily determined by radiality in EVC but by co-axiality in perception. Despite this mismatch, the individual differences in both radial and co-axial anisotropy are substantially shared between EVC and perception. Our findings suggest that spatial extent perception builds on EVC's spatial representation but requires an additional mechanism to transform its topographic bias.
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Affiliation(s)
- Juhyoung Ryu
- Department of Brain and Cognitive Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sang-Hun Lee
- Department of Brain and Cognitive Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
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4
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Wu EG, Rudzite AM, Bohlen MO, Li PH, Kling A, Cooler S, Rhoades C, Brackbill N, Gogliettino AR, Shah NP, Madugula SS, Sher A, Litke AM, Field GD, Chichilnisky E. Decomposition of retinal ganglion cell electrical images for cell type and functional inference. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.06.565889. [PMID: 37986895 PMCID: PMC10659265 DOI: 10.1101/2023.11.06.565889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Identifying neuronal cell types and their biophysical properties based on their extracellular electrical features is a major challenge for experimental neuroscience and the development of high-resolution brain-machine interfaces. One example is identification of retinal ganglion cell (RGC) types and their visual response properties, which is fundamental for developing future electronic implants that can restore vision. The electrical image (EI) of a RGC, or the mean spatio-temporal voltage footprint of its recorded spikes on a high-density electrode array, contains substantial information about its anatomical, morphological, and functional properties. However, the analysis of these properties is complex because of the high-dimensional nature of the EI. We present a novel optimization-based algorithm to decompose electrical image into a low-dimensional, biophysically-based representation: the temporally-shifted superposition of three learned basis waveforms corresponding to spike waveforms produced in the somatic, dendritic and axonal cellular compartments. Large-scale multi-electrode recordings from the macaque retina were used to test the effectiveness of the decomposition. The decomposition accurately localized the somatic and dendritic compartments of the cell. The imputed dendritic fields of RGCs correctly predicted the location and shape of their visual receptive fields. The inferred waveform amplitudes and shapes accurately identified the four major primate RGC types (ON and OFF midget and parasol cells), a substantial advance. Together, these findings may contribute to more accurate inference of RGC types and their original light responses in the degenerated retina, with possible implications for other electrical imaging applications.
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Affiliation(s)
- Eric G. Wu
- Department of Electrical Engineering, Stanford University
| | | | | | - Peter H. Li
- Department of Neurosurgery, Stanford University
- Department of Ophthalmology, Stanford University
- Hansen Experimental Physics Laboratory, Stanford University
| | - Alexandra Kling
- Department of Neurosurgery, Stanford University
- Department of Ophthalmology, Stanford University
- Hansen Experimental Physics Laboratory, Stanford University
| | - Sam Cooler
- Department of Neurosurgery, Stanford University
| | | | | | | | - Nishal P. Shah
- Department of Electrical Engineering, Stanford University
- Department of Neurosurgery, Stanford University
| | - Sasidhar S. Madugula
- Neurosciences PhD Program, Stanford University
- Stanford School of Medicine, Stanford University
| | - Alexander Sher
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz
| | - Alan M. Litke
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz
| | - Greg D. Field
- Department of Neurobiology, Duke University
- Stein Eye Institute, Department of Ophthalmology, University of California, Los Angeles
| | - E.J. Chichilnisky
- Department of Neurosurgery, Stanford University
- Department of Ophthalmology, Stanford University
- Hansen Experimental Physics Laboratory, Stanford University
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5
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Madugula SS, Vilkhu R, Shah NP, Grosberg LE, Kling A, Gogliettino AR, Nguyen H, Hottowy P, Sher A, Litke AM, Chichilnisky EJ. Inference of Electrical Stimulation Sensitivity from Recorded Activity of Primate Retinal Ganglion Cells. J Neurosci 2023; 43:4808-4820. [PMID: 37268418 PMCID: PMC10312054 DOI: 10.1523/jneurosci.1023-22.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 05/22/2023] [Accepted: 05/24/2023] [Indexed: 06/04/2023] Open
Abstract
High-fidelity electronic implants can in principle restore the function of neural circuits by precisely activating neurons via extracellular stimulation. However, direct characterization of the individual electrical sensitivity of a large population of target neurons, to precisely control their activity, can be difficult or impossible. A potential solution is to leverage biophysical principles to infer sensitivity to electrical stimulation from features of spontaneous electrical activity, which can be recorded relatively easily. Here, this approach is developed and its potential value for vision restoration is tested quantitatively using large-scale multielectrode stimulation and recording from retinal ganglion cells (RGCs) of male and female macaque monkeys ex vivo Electrodes recording larger spikes from a given cell exhibited lower stimulation thresholds across cell types, retinas, and eccentricities, with systematic and distinct trends for somas and axons. Thresholds for somatic stimulation increased with distance from the axon initial segment. The dependence of spike probability on injected current was inversely related to threshold, and was substantially steeper for axonal than somatic compartments, which could be identified by their recorded electrical signatures. Dendritic stimulation was largely ineffective for eliciting spikes. These trends were quantitatively reproduced with biophysical simulations. Results from human RGCs were broadly similar. The inference of stimulation sensitivity from recorded electrical features was tested in a data-driven simulation of visual reconstruction, revealing that the approach could significantly improve the function of future high-fidelity retinal implants.SIGNIFICANCE STATEMENT This study demonstrates that individual in situ primate retinal ganglion cells of different types respond to artificially generated, external electrical fields in a systematic manner, in accordance with theoretical predictions, that allows for prediction of electrical stimulus sensitivity from recorded spontaneous activity. It also provides evidence that such an approach could be immensely helpful in the calibration of clinical retinal implants.
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Affiliation(s)
- Sasidhar S Madugula
- Neurosciences PhD Program, Stanford University, Stanford, California 94305
- School of Medicine, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
| | - Ramandeep Vilkhu
- Department of Electrical Engineering, Stanford University, Stanford, California 94305
| | - Nishal P Shah
- Department of Neurosurgery, Stanford University, Stanford, California 94305
- Department of Electrical Engineering, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
| | - Lauren E Grosberg
- Department of Neurosurgery, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Facebook Reality Labs, Facebook, Mountain View, California 94040
| | - Alexandra Kling
- Department of Neurosurgery, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
| | - Alex R Gogliettino
- Neurosciences PhD Program, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
| | - Huy Nguyen
- Department of Neurosurgery, Stanford University, Stanford, California 94305
| | - Paweł Hottowy
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Krakow, Poland 30-059
| | - Alexander Sher
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, California 95064
| | - Alan M Litke
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, California 95064
| | - E J Chichilnisky
- Department of Neurosurgery, Stanford University, Stanford, California 94305
- Department of Ophthalmology, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
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6
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Gogliettino AR, Madugula SS, Grosberg LE, Vilkhu RS, Brown J, Nguyen H, Kling A, Hottowy P, Dąbrowski W, Sher A, Litke AM, Chichilnisky EJ. High-Fidelity Reproduction of Visual Signals by Electrical Stimulation in the Central Primate Retina. J Neurosci 2023; 43:4625-4641. [PMID: 37188516 PMCID: PMC10286946 DOI: 10.1523/jneurosci.1091-22.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 05/17/2023] Open
Abstract
Electrical stimulation of retinal ganglion cells (RGCs) with electronic implants provides rudimentary artificial vision to people blinded by retinal degeneration. However, current devices stimulate indiscriminately and therefore cannot reproduce the intricate neural code of the retina. Recent work has demonstrated more precise activation of RGCs using focal electrical stimulation with multielectrode arrays in the peripheral macaque retina, but it is unclear how effective this can be in the central retina, which is required for high-resolution vision. This work probes the neural code and effectiveness of focal epiretinal stimulation in the central macaque retina, using large-scale electrical recording and stimulation ex vivo The functional organization, light response properties, and electrical properties of the major RGC types in the central retina were mostly similar to the peripheral retina, with some notable differences in density, kinetics, linearity, spiking statistics, and correlations. The major RGC types could be distinguished by their intrinsic electrical properties. Electrical stimulation targeting parasol cells revealed similar activation thresholds and reduced axon bundle activation in the central retina, but lower stimulation selectivity. Quantitative evaluation of the potential for image reconstruction from electrically evoked parasol cell signals revealed higher overall expected image quality in the central retina. An exploration of inadvertent midget cell activation suggested that it could contribute high spatial frequency noise to the visual signal carried by parasol cells. These results support the possibility of reproducing high-acuity visual signals in the central retina with an epiretinal implant.SIGNIFICANCE STATEMENT Artificial restoration of vision with retinal implants is a major treatment for blindness. However, present-day implants do not provide high-resolution visual perception, in part because they do not reproduce the natural neural code of the retina. Here, we demonstrate the level of visual signal reproduction that is possible with a future implant by examining how accurately responses to electrical stimulation of parasol retinal ganglion cells can convey visual signals. Although the precision of electrical stimulation in the central retina was diminished relative to the peripheral retina, the quality of expected visual signal reconstruction in parasol cells was greater. These findings suggest that visual signals could be restored with high fidelity in the central retina using a future retinal implant.
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Affiliation(s)
- Alex R Gogliettino
- Neurosciences PhD Program, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
| | - Sasidhar S Madugula
- Neurosciences PhD Program, Stanford University, Stanford, California 94305
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Stanford School of Medicine, Stanford University, Stanford, California 94305
| | - Lauren E Grosberg
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Department of Neurosurgery, Stanford University, Stanford, California 94305
| | - Ramandeep S Vilkhu
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Department of Electrical Engineering, Stanford University, Stanford, California 94305
| | - Jeff Brown
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Department of Neurosurgery, Stanford University, Stanford, California 94305
- Department of Electrical Engineering, Stanford University, Stanford, California 94305
| | - Huy Nguyen
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
| | - Alexandra Kling
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Department of Neurosurgery, Stanford University, Stanford, California 94305
| | - Paweł Hottowy
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30-059, Kraków, Poland
| | - Władysław Dąbrowski
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30-059, Kraków, Poland
| | - Alexander Sher
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, Santa Cruz, California 95064
| | - Alan M Litke
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, Santa Cruz, California 95064
| | - E J Chichilnisky
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305
- Department of Neurosurgery, Stanford University, Stanford, California 94305
- Department of Electrical Engineering, Stanford University, Stanford, California 94305
- Department of Ophthalmology, Stanford University, Stanford, California 94305
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7
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Contribution of parasol-magnocellular pathway ganglion cells to foveal retina in macaque monkey. Vision Res 2023; 202:108154. [PMID: 36436365 DOI: 10.1016/j.visres.2022.108154] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/18/2022] [Accepted: 10/28/2022] [Indexed: 11/25/2022]
Abstract
Parasol-magnocellular pathway ganglion cells form an important output stream of the primate retina and make a major contribution to visual motion detection. They are known to comprise ON and OFF type response polarities but the relative numbers of ON and OFF parasol cells, and the overall contribution of parasol cells to high-acuity foveal vision are not well understood. Here we use antibodies against carbonic anhydrase 8 (CA8) and intracellular injections of the liphilic dye DiI to show that CA8 selectively labels OFF parasol cells in macaque retina. By combined labeling with CA8 antibodies and a previously-described marker for parasol cells (GABAA receptor antibodies), we show that ON and OFF parasol cells each comprise ∼ 6% of all ganglion cells in central retina (each peak density ∼ 3000 cells/mm2 at 5 deg.), and each population comprises ∼ 10% of all ganglion cells in peripheral temporal retina. Thus, the spatial density of parasol cells in central retina is greater than reported by previous anatomical studies, and the central-peripheral gradient in parasol cell density is shallower than previously reported. The data nevertheless predict decline in spatial acuity with visual field eccentricity for both midget-parvocellular pathway and parasol-magnocellular pathway mediated visual functions. The spatial resolving power of the OFF parasol array (peak ∼ 7 cpd) falls short of macaque behavioral grating acuity by at least a factor of three throughout the retina.
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In vivo chromatic and spatial tuning of foveolar retinal ganglion cells in Macaca fascicularis. PLoS One 2022; 17:e0278261. [PMID: 36445926 PMCID: PMC9707781 DOI: 10.1371/journal.pone.0278261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 11/13/2022] [Indexed: 11/30/2022] Open
Abstract
The primate fovea is specialized for high acuity chromatic vision, with the highest density of cone photoreceptors and a disproportionately large representation in visual cortex. The unique visual properties conferred by the fovea are conveyed to the brain by retinal ganglion cells, the somas of which lie at the margin of the foveal pit. Microelectrode recordings of these centermost retinal ganglion cells have been challenging due to the fragility of the fovea in the excised retina. Here we overcome this challenge by combining high resolution fluorescence adaptive optics ophthalmoscopy with calcium imaging to optically record functional responses of foveal retinal ganglion cells in the living eye. We use this approach to study the chromatic responses and spatial transfer functions of retinal ganglion cells using spatially uniform fields modulated in different directions in color space and monochromatic drifting gratings. We recorded from over 350 cells across three Macaca fascicularis primates over a time period of weeks to months. We find that the majority of the L vs. M cone opponent cells serving the most central foveolar cones have spatial transfer functions that peak at high spatial frequencies (20-40 c/deg), reflecting strong surround inhibition that sacrifices sensitivity at low spatial frequencies but preserves the transmission of fine detail in the retinal image. In addition, we fit to the drifting grating data a detailed model of how ganglion cell responses draw on the cone mosaic to derive receptive field properties of L vs. M cone opponent cells at the very center of the foveola. The fits are consistent with the hypothesis that foveal midget ganglion cells are specialized to preserve information at the resolution of the cone mosaic. By characterizing the functional properties of retinal ganglion cells in vivo through adaptive optics, we characterize the response characteristics of these cells in situ.
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Italiano ML, Guo T, Lovell NH, Tsai D. Improving the spatial resolution of artificial vision using midget retinal ganglion cell populations modelled at the human fovea. J Neural Eng 2022; 19. [PMID: 35609556 DOI: 10.1088/1741-2552/ac72c2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 05/24/2022] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Retinal prostheses seek to create artificial vision by stimulating surviving retinal neurons of patients with profound vision impairment. Notwithstanding tremendous research efforts, the performance of all implants tested to date has remained rudimentary, incapable of overcoming the threshold for legal blindness. To maximize the perceptual efficacy of retinal prostheses, a device must be capable of controlling retinal neurons with greater spatiotemporal precision. Most studies of retinal stimulation were derived from either non-primate species or the peripheral primate retina. We investigated if artificial stimulation could leverage the high spatial resolution afforded by the neural substrates at the primate fovea and surrounding regions to achieve improved percept qualities. APPROACH We began by developing a new computational model capable of generating anatomically accurate retinal ganglion cell (RGC) populations within the human central retina. Next, multiple RGC populations across the central retina were stimulated in-silico to compare clinical and recently proposed neurostimulation configurations based on their ability to improve perceptual efficacy and reduce activation thresholds. MAIN RESULTS Our model uniquely upholds eccentricity-dependent characteristics such as RGC density and dendritic field diameter, whilst incorporating anatomically accurate features such as axon projection and three-dimensional RGC layering, features often forgone in favor of reduced computational complexity. Following epiretinal stimulation, the RGCs in our model produced response patterns in shapes akin to the complex percepts reported in clinical trials. Our results also demonstrated that even within the neuron-dense central retina, epiretinal stimulation using a multi-return hexapolar electrode arrangement could reliably achieve spatially focused RGC activation and could achieve single-cell excitation in 74% of all tested locations. SIGNIFICANCE This study establishes an anatomically accurate three-dimensional model of the human central retina and demonstrates the potential for an epiretinal hexapolar configuration to achieve consistent, spatially confined retinal responses, even within the neuron-dense foveal region. Our results promote the prospect and optimization of higher spatial resolution in future epiretinal implants.
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Affiliation(s)
- Michael Lewis Italiano
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Sydney, New South Wales, 2052, AUSTRALIA
| | - Tianruo Guo
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Sydney, New South Wales, 2052, AUSTRALIA
| | - Nigel H Lovell
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Sydney, New South Wales, 2052, AUSTRALIA
| | - David Tsai
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Sydney, New South Wales, 2052, AUSTRALIA
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Hathibelagal AR, Manoharan MK, Verkicharla PK. Do myopes have deficits in peripheral flicker sensitivity? JOURNAL OF OPTOMETRY 2022; 15:138-144. [PMID: 33849791 PMCID: PMC9068563 DOI: 10.1016/j.optom.2021.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/09/2020] [Accepted: 01/06/2021] [Indexed: 06/12/2023]
Abstract
PURPOSE Signals from the peripheral retina are important for myopia development. Unlike temporal vision, deficits in peripheral spatial visual functions of myopes have been investigated previously. This study investigated temporal contrast thresholds in emmetropes and myopes at different retinal eccentricities. METHODS Forty-four young adults (mean age 23 ± 3 years) including 21 emmetropes (Spherical Equivalent (SE): +0.01 ± 0.30D) and 23 myopes (SE: -3.98 ± 2.41D) participated in this prospective study. Flicker modulation thresholds (FMT) were determined monocularly (right eye) for 15 Hz flicker stimulus at 0°, nasal (23°, 10°) and temporal (-23°, -10°) retinal eccentricities along the horizontal meridian. FMTs were measured psychophysically using 5-adaptive interleaved staircases and threshold was taken as the average of the last 6 reversals. RESULTS In both the groups (emmetropes and myopes), there was a naso-temporal asymmetry in FMTs with higher thresholds in the far temporal retina (Median; Interquartile range: 40.97%; 17.06) than the nasal retina (28.07%; 9.36) (p < 0.001). Flicker modulation thresholds were significantly higher in myopes (30.58%; 12.15) compared to emmetropes (26.77%; 7.74; p = 0.04) at far nasal retina (23°), while at other eccentricities there was no effect (p > 0.05). Further sub-analysis revealed only high myopes (34.48 %, 21.9) showed significantly higher FMT compared to emmetropes (26.77%; 7.74; p = 0.04). CONCLUSION Greater FMTs were seen in high myopes than that of emmetropes in the nasal retina. Further studies exploring the structural aspects of the myopic eye with FMT would provide a better understanding of role of flicker sensitivity in myopiogenesis.
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Affiliation(s)
- Amithavikram R Hathibelagal
- Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Road No. 2, Banjara Hills, Kallam Anji Reddy Campus, Hyderabad 500034, India.
| | - Manoj K Manoharan
- Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Road No. 2, Banjara Hills, Kallam Anji Reddy Campus, Hyderabad 500034, India; Myopia Research Lab - Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
| | - Pavan K Verkicharla
- Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Road No. 2, Banjara Hills, Kallam Anji Reddy Campus, Hyderabad 500034, India; Myopia Research Lab - Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India.
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11
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Baumgarten S, Hoberg T, Lohmann T, Mazinani B, Walter P, Koutsonas A. Fullfield and extrafoveal visual evoked potentials in healthy eyes: reference data for a curved OLED display. Doc Ophthalmol 2022; 145:247-262. [PMID: 36087163 PMCID: PMC9653365 DOI: 10.1007/s10633-022-09897-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 08/24/2022] [Indexed: 12/29/2022]
Abstract
PURPOSE Visual evoked potentials (VEP) present an important diagnostic tool in various ophthalmologic and neurologic diseases. Quantitative response data varied among patients but are also dependent on the recording and stimulating equipment. We established VEP reference values for our setting which was recently modified by using a curved OLED display as visual stimulator. Distinction is made between fullfield (FF) and extrafoveal (EF) conduction, and the effect of sex, age and lens status was determined. METHODS This prospective cross-sectional study included 162 healthy eyes of 162 test persons older than 10 years. A fullfield pattern-reversal visual evoked potential (FF-PR-VEP) with two stimulus sizes (ss) (20.4' and 1.4°) as well as an extrafoveal pattern onset-offset VEP (EF-P-ON/OFF-VEP) (ss 1.4° and 2.8°) was derived in accordance with the International Society for Clinical Electrophysiology of Vision guidelines. Amplitudes and latencies were recorded, and the mean values as well as standard deviations were calculated. Age- and sex-dependent influences and the difference between phakic and pseudophakic eyes were examined. A subanalysis of EF-P-ON/OFF-VEP and fullfield pattern onset-offset VEP (FF-P-ON/OFF-VEP) was performed. A 55-inch curved OLED display (LG55EC930V, LG Electronics Inc., Seoul, South Korea) was used as visual stimulator. RESULTS Mean P100 latency of the FF-PR-VEP was 103.81 ± 7.77 ms (ss 20.4') and 102.58 ± 7.26 ms (ss 1.4°), and mean C2 latency of the EF-P-ON/OFF-VEP was 102.95 ± 11.84 ms (ss 1.4°) and 113.58 ± 9.87 ms (ss 2.8°). For all stimulation settings (FF-PR-VEP, EF-P-ON/OFF-VEP), a significant effect of age with longer latencies and smaller amplitudes in older subjects and higher amplitudes in women was observed. We saw no significant difference in latency or amplitude between phakic and pseudophakic eyes and between EF-P-ON/OFF-VEP and FF-P-ON/OFF-VEP. CONCLUSIONS A curved OLED visual stimulator is well suited to obtain VEP response curves with a reasonable interindividual variability. We found significant effects of age and gender in our responses but no effect of the lens status. EF-P-ON/OFF-VEP tends to show smaller amplitudes.
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Affiliation(s)
- Sabine Baumgarten
- grid.1957.a0000 0001 0728 696XDepartment of Ophthalmology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Tabea Hoberg
- grid.1957.a0000 0001 0728 696XDepartment of Ophthalmology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Tibor Lohmann
- grid.1957.a0000 0001 0728 696XDepartment of Ophthalmology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Babac Mazinani
- grid.1957.a0000 0001 0728 696XDepartment of Ophthalmology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Peter Walter
- grid.1957.a0000 0001 0728 696XDepartment of Ophthalmology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Antonis Koutsonas
- grid.1957.a0000 0001 0728 696XDepartment of Ophthalmology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
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12
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Raghuram V, Werginz P, Fried SI, Timko BP. Morphological Factors that Underlie Neural Sensitivity to Stimulation in the Retina. ADVANCED NANOBIOMED RESEARCH 2021; 1:2100069. [PMID: 35399546 PMCID: PMC8993153 DOI: 10.1002/anbr.202100069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Retinal prostheses are a promising therapeutic intervention for patients afflicted by outer retinal degenerative diseases like retinitis pigmentosa and age-related macular degeneration. While significant advances in the development of retinal implants have been made, the quality of vision elicited by these devices remains largely sub-optimal. The variability in the responses produced by retinal devices is most likely due to the differences between the natural cell type-specific signaling that occur in the healthy retina vs. the non-specific activation of multiple cell types arising from artificial stimulation. In order to replicate these natural signaling patterns, stimulation strategies must be capable of preferentially activating specific RGC types. To design more selective stimulation strategies, a better understanding of the morphological factors that underlie the sensitivity to prosthetic stimulation must be developed. This review will focus on the role that different anatomical components play in driving the direct activation of RGCs by extracellular stimulation. Briefly, it will (1) characterize the variability in morphological properties of α-RGCs, (2) detail the influence of morphology on the direct activation of RGCs by electric stimulation, and (3) describe some of the potential biophysical mechanisms that could explain differences in activation thresholds and electrically evoked responses between RGC types.
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Affiliation(s)
- Vineeth Raghuram
- Boston VA Healthcare System, 150 S Huntington Ave, Boston, MA 02130, USA
- Dept. of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
- Dept. of Neurosurgery, Massachusetts General Hospital - Harvard Medical School, 50 Blossom Street, Boston, MA, 02114
| | - Paul Werginz
- Institute for Analysis and Scientific Computing, Vienna University of Technology, Wiedner Hauptstrasse 8-10, Vienna, Austria
- Dept. of Neurosurgery, Massachusetts General Hospital - Harvard Medical School, 50 Blossom Street, Boston, MA, 02114
| | - Shelley I. Fried
- Boston VA Healthcare System, 150 S Huntington Ave, Boston, MA 02130, USA
- Dept. of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
- Dept. of Neurosurgery, Massachusetts General Hospital - Harvard Medical School, 50 Blossom Street, Boston, MA, 02114
| | - Brian P. Timko
- Dept. of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
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13
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Grünert U, Martin PR. Morphology, Molecular Characterization, and Connections of Ganglion Cells in Primate Retina. Annu Rev Vis Sci 2021; 7:73-103. [PMID: 34524877 DOI: 10.1146/annurev-vision-100419-115801] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The eye sends information about the visual world to the brain on over 20 parallel signal pathways, each specialized to signal features such as spectral reflection (color), edges, and motion of objects in the environment. Each pathway is formed by the axons of a separate type of retinal output neuron (retinal ganglion cell). In this review, we summarize what is known about the excitatory retinal inputs, brain targets, and gene expression patterns of ganglion cells in humans and nonhuman primates. We describe how most ganglion cell types receive their input from only one or two of the 11 types of cone bipolar cell and project selectively to only one or two target regions in the brain. We also highlight how genetic methods are providing tools to characterize ganglion cells and establish cross-species homologies.
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Affiliation(s)
- Ulrike Grünert
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney NSW 2000, Australia; , .,Sydney Node, Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney NSW 2000, Australia
| | - Paul R Martin
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney NSW 2000, Australia; , .,Sydney Node, Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney NSW 2000, Australia
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14
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Roy S, Jun NY, Davis EL, Pearson J, Field GD. Inter-mosaic coordination of retinal receptive fields. Nature 2021; 592:409-413. [PMID: 33692544 PMCID: PMC8049984 DOI: 10.1038/s41586-021-03317-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 02/01/2021] [Indexed: 11/09/2022]
Abstract
The output of the retina is organized into many detector grids, called ‘mosaics’ that signal different features of visual scenes to the brain1–4. Each mosaic comprises a single retinal ganglion cell (RGC) type, whose receptive fields (RFs) tile space. Many mosaics arise as pairs, signaling increments (ON) and decrements (OFF), respectively, of a particular visual feature5. Using a model of efficient coding6, we determine how such mosaic pairs should be arranged to optimize the encoding of natural scenes. We find that information is maximized when these mosaic pairs are anti-aligned, meaning the RF centers between mosaics are more distant than expected by chance. We test this prediction across multiple RF mosaics acquired with large-scale measurements of RGC light responses from rat and primate. We find that ON and OFF RGC pairs with similar feature selectivity exhibit anti-aligned RF mosaics, consistent with theory. ON and OFF types that encode distinct features exhibit independent mosaics. These results extend efficient coding theory (ECT) beyond individual cells to predict how populations of diverse RGC types are spatially arranged.
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Affiliation(s)
- Suva Roy
- Department of Neurobiology, Duke University, Durham, NC, USA
| | - Na Young Jun
- Department of Neurobiology, Duke University, Durham, NC, USA
| | - Emily L Davis
- Department of Neurobiology, Duke University, Durham, NC, USA
| | - John Pearson
- Department of Neurobiology, Duke University, Durham, NC, USA.,Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA
| | - Greg D Field
- Department of Neurobiology, Duke University, Durham, NC, USA.
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15
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Famiglietti EV. Morphological identification and systematic classification of mammalian retinal ganglion cells. I. Rabbit retinal ganglion cells. J Comp Neurol 2020; 528:3305-3450. [PMID: 32725618 DOI: 10.1002/cne.24998] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 07/21/2020] [Accepted: 07/21/2020] [Indexed: 11/10/2022]
Abstract
Retinal ganglion cells (RGCs) convey visual signals to 50 regions of the brain. For reasons of interest and convenience, they constitute an excellent system for the study of brain structure and function. There is general agreement that, absent a complete "parts list," understanding how the nervous system processes information will remain an elusive goal. Recent studies indicate that there are 30-50 types of ganglion cell in mouse retina, whereas only a few years ago it was still written that mice and the more visually oriented lagomorphs had less than 20 types of RGC. More than 30 years ago, I estimated that rabbits have about 40 types of RGC. The present study indicates that this number is much too low. I have employed the old but powerful method of Golgi-impregnation to rabbit retina, studying the range of component neurons in this already well-studied retinal system. Close quantitative and qualitative analyses of 1,142 RGCs in 26 retinas take into account cell body and dendritic field size, level(s) of dendritic stratification in the retina's inner plexiform layer, and details of dendritic branching. Ninety-one morphologies are recognized. Of these, at least 32 can be correlated with physiologically studied RGCs, dye-injected for morphological analysis. It is unlikely that rabbits have 91 types of RGC, but is argued here that this number lies between 60 and 70. The present study provides a "yardstick" for measuring the output of future molecular studies that may be more definitive in fixing the number of RGC types in rabbit retina.
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Affiliation(s)
- Edward V Famiglietti
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, Rhode Island, USA.,Division of Ophthalmology, Rhode Island Hospital, Providence, Rhode Island, USA
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16
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Miller DT, Kurokawa K. Cellular-Scale Imaging of Transparent Retinal Structures and Processes Using Adaptive Optics Optical Coherence Tomography. Annu Rev Vis Sci 2020; 6:115-148. [PMID: 32609578 PMCID: PMC7864592 DOI: 10.1146/annurev-vision-030320-041255] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High-resolution retinal imaging is revolutionizing how scientists and clinicians study the retina on the cellular scale. Its exquisite sensitivity enables time-lapse optical biopsies that capture minute changes in the structure and physiological processes of cells in the living eye. This information is increasingly used to detect disease onset and monitor disease progression during early stages, raising the possibility of personalized eye care. Powerful high-resolution imaging tools have been in development for more than two decades; one that has garnered considerable interest in recent years is optical coherence tomography enhanced with adaptive optics. State-of-the-art adaptive optics optical coherence tomography (AO-OCT) makes it possible to visualize even highly transparent cells and measure some of their internal processes at all depths within the retina, permitting reconstruction of a 3D view of the living microscopic retina. In this review, we report current AO-OCT performance and its success in visualizing and quantifying these once-invisible cells in human eyes.
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Affiliation(s)
- Donald T Miller
- School of Optometry, Indiana University, Bloomington, Indiana 47405, USA; ,
| | - Kazuhiro Kurokawa
- School of Optometry, Indiana University, Bloomington, Indiana 47405, USA; ,
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17
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Abstract
A retina completely devoid of topographic variations would be homogenous, encoding any given feature uniformly across the visual field. In a naive view, such homogeneity would appear advantageous. However, it is now clear that retinal topographic variations exist across mammalian species in a variety of forms and patterns. We briefly review some of the more established topographic variations in retinas of different mammalian species and focus on the recent discovery that cells belonging to a single neuronal subtype may exhibit distinct topographic variations in distribution, morphology, and even function. We concentrate on the mouse retina-originally viewed as homogenous-in which genetic labeling of distinct neuronal subtypes and other advanced techniques have revealed unexpected anatomical and physiological topographic variations. Notably, different subtypes reveal different patterns of nonuniformity, which may even be opposite or orthogonal to one another. These topographic variations in the encoding of visual space should be considered when studying visual processing in the retina and beyond.
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Affiliation(s)
- Alina Sophie Heukamp
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 7610001, Israel; , ,
| | - Rebekah Anne Warwick
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 7610001, Israel; , ,
| | - Michal Rivlin-Etzion
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 7610001, Israel; , ,
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18
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Werginz P, Raghuram V, Fried SI. The relationship between morphological properties and thresholds to extracellular electric stimulation in α RGCs. J Neural Eng 2020; 17:045015. [PMID: 32736374 DOI: 10.1088/1741-2552/abab47] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Retinal prostheses strive to restore vison to patients that are blind from retinal degeneration by electrically stimulating surviving retinal ganglion cells (RGCs). The quality of elicited percepts remains limited however and it is desirable to develop improved stimulation strategies. Here, we examine how the anatomical and biophysical properties of RGCs influence activation thresholds, including the effects of variations found naturally. APPROACH Detailed reconstructions were made of a large number of mouse α RGCs and were used to create an array of model cells; the models were used to study the effects of individual anatomical features on activation threshold to electric stimulation. Stimulation was delivered epiretinally from a point-source or disk electrode and consisted of monophasic or biphasic rectangular pulses. MAIN RESULTS Modeling results show that the region of minimum threshold always is within the axon initial segment (AIS). The properties of this region as well as the absolute value of the minimum threshold are dependent on the length of the AIS as well as on the relative composition of sodium channels within the AIS. Other morphological features, including cell size, dendritic field size and the distance between the AIS and the soma had only a minimal influence on thresholds. Introducing even a small number of low-threshold Nav1.6 channels into the AIS was sufficient to lower minimum thresholds substantially although further increases in Nav1.6 had diminishing effects. The distance between the AIS and the electrode affects threshold levels while alignment of the electrode with the axon or dendritic parts of the RGC can result in lower thresholds, even if the distance to the cell remains the same. SIGNIFICANCE Intrinsic morphological features can influence activation thresholds with the AIS having the strongest influence. However, the combined influence remains limited and may not be large enough to allow for selective activation between different RGC types.
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Affiliation(s)
- Paul Werginz
- Institute for Analysis and Scientific Computing, Vienna University of Technology, Vienna, Austria. Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America. Author to whom any correspondence should be addressed
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19
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Abstract
In this review, I develop an empirically based model of optical image formation by the human eye, followed by neural sampling by retinal ganglion cells, to demonstrate the perceptual effects of blur, aliasing, and distortion of visual space in the brain. The optical model takes account of ocular aberrations and their variation across the visual field, in addition to variations of defocus due to variation of target vergence in three-dimensional scenes. Neural sampling by retinal ganglion cells with receptive field size and spacing that increases with eccentricity is used to visualize the neural image carried by the optic nerve to the brain. Anatomical parameters are derived from psychophysical studies of sampling-limited visual resolution of sinusoidal interference fringes. Retinotopic projection of the neural image onto brainstem nuclei reveals features of the neural image in a perceptually uniform brain space where location and size of visual objects may be measured by counting neurons.
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Affiliation(s)
- Larry N Thibos
- School of Optometry, Indiana University, Bloomington, Indiana 47405, USA;
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20
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Patterson SS, Bordt AS, Girresch RJ, Linehan CM, Bauss J, Yeo E, Perez D, Tseng L, Navuluri S, Harris NB, Matthews C, Anderson JR, Kuchenbecker JA, Manookin MB, Ogilvie JM, Neitz J, Marshak DW. Wide-field amacrine cell inputs to ON parasol ganglion cells in macaque retina. J Comp Neurol 2020; 528:1588-1598. [PMID: 31845339 PMCID: PMC7153979 DOI: 10.1002/cne.24840] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/31/2019] [Accepted: 11/24/2019] [Indexed: 11/07/2022]
Abstract
Parasol cells are one of the major types of primate retinal ganglion cells. The goal of this study was to describe the synaptic inputs that shape the light responses of the ON type of parasol cells, which are excited by increments in light intensity. A connectome from central macaque retina was generated by serial blockface scanning electron microscopy. Six neighboring ON parasol cells were reconstructed, and their synaptic inputs were analyzed. On average, they received 21% of their input from bipolar cells, excitatory local circuit neurons receiving input from cones. The majority of their input was from amacrine cells, local circuit neurons of the inner retina that are typically inhibitory. Their contributions to the neural circuit providing input to parasol cells are not well-understood, and the focus of this study was on the presynaptic wide-field amacrine cells, which provided 17% of the input to ON parasol cells. These are GABAergic amacrine cells with long, relatively straight dendrites, and sometimes also axons, that run in a single, narrow stratum of the inner plexiform layer. The presynaptic wide-field amacrine cells were reconstructed, and two types were identified based on their characteristic morphology. One presynaptic amacrine cell was identified as semilunar type 2, a polyaxonal cell that is electrically coupled to ON parasol cells. A second amacrine was identified as wiry type 2, a type known to be sensitive to motion. These inputs likely make ON parasol cells more sensitive to stimuli that are rapidly changing outside their classical receptive fields.
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Affiliation(s)
- Sara S Patterson
- Department of Ophthalmology, University of Washington, Seattle, Washington
- Neuroscience Graduate Program, University of Washington, Seattle, Washington
| | - Andrea S Bordt
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
| | | | - Conor M Linehan
- Department of Ophthalmology, University of Washington, Seattle, Washington
| | - Jacob Bauss
- Department of Biology, Saint Louis University, Saint Louis, Missouri
| | - Eunice Yeo
- Department of Biology, Saint Louis University, Saint Louis, Missouri
| | - Diego Perez
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
| | - Luke Tseng
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
| | - Sriram Navuluri
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
| | - Nicole B Harris
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
| | - Chaiss Matthews
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
| | - James R Anderson
- John A. Moran Eye Center, University of Utah, Salt Lake City, Utah
| | | | - Michael B Manookin
- Department of Ophthalmology, University of Washington, Seattle, Washington
| | - Judith M Ogilvie
- Department of Biology, Saint Louis University, Saint Louis, Missouri
| | - Jay Neitz
- Department of Ophthalmology, University of Washington, Seattle, Washington
| | - David W Marshak
- Department of Neurobiology & Anatomy, McGovern Medical School, Houston, Texas
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21
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Appleby TR, Manookin MB. Selectivity to approaching motion in retinal inputs to the dorsal visual pathway. eLife 2020; 9:e51144. [PMID: 32091390 PMCID: PMC7080407 DOI: 10.7554/elife.51144] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 02/18/2020] [Indexed: 11/13/2022] Open
Abstract
To efficiently navigate through the environment and avoid potential threats, an animal must quickly detect the motion of approaching objects. Current models of primate vision place the origins of this complex computation in the visual cortex. Here, we report that detection of approaching motion begins in the retina. Several ganglion cell types, the retinal output neurons, show selectivity to approaching motion. Synaptic current recordings from these cells further reveal that this preference for approaching motion arises in the interplay between presynaptic excitatory and inhibitory circuit elements. These findings demonstrate how excitatory and inhibitory circuits interact to mediate an ethologically relevant neural function. Moreover, the elementary computations that detect approaching motion begin early in the visual stream of primates.
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Affiliation(s)
- Todd R Appleby
- Graduate Program in Neuroscience, University of WashingtonSeattleUnited States
- Department of Ophthalmology, University of WashingtonSeattleUnited States
- Vision Science Center, University of WashingtonSeattleUnited States
| | - Michael B Manookin
- Department of Ophthalmology, University of WashingtonSeattleUnited States
- Vision Science Center, University of WashingtonSeattleUnited States
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22
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Grünert U, Martin PR. Cell types and cell circuits in human and non-human primate retina. Prog Retin Eye Res 2020; 78:100844. [PMID: 32032773 DOI: 10.1016/j.preteyeres.2020.100844] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/28/2020] [Accepted: 01/31/2020] [Indexed: 12/12/2022]
Abstract
This review summarizes our current knowledge of primate including human retina focusing on bipolar, amacrine and ganglion cells and their connectivity. We have two main motivations in writing. Firstly, recent progress in non-invasive imaging methods to study retinal diseases mean that better understanding of the primate retina is becoming an important goal both for basic and for clinical sciences. Secondly, genetically modified mice are increasingly used as animal models for human retinal diseases. Thus, it is important to understand to which extent the retinas of primates and rodents are comparable. We first compare cell populations in primate and rodent retinas, with emphasis on how the fovea (despite its small size) dominates the neural landscape of primate retina. We next summarise what is known, and what is not known, about the postreceptoral neurone populations in primate retina. The inventories of bipolar and ganglion cells in primates are now nearing completion, comprising ~12 types of bipolar cell and at least 17 types of ganglion cell. Primate ganglion cells show clear differences in dendritic field size across the retina, and their morphology differs clearly from that of mouse retinal ganglion cells. Compared to bipolar and ganglion cells, amacrine cells show even higher morphological diversity: they could comprise over 40 types. Many amacrine types appear conserved between primates and mice, but functions of only a few types are understood in any primate or non-primate retina. Amacrine cells appear as the final frontier for retinal research in monkeys and mice alike.
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Affiliation(s)
- Ulrike Grünert
- The University of Sydney, Save Sight Institute, Faculty of Medicine and Health, Sydney, NSW, 2000, Australia; Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, NSW, 2000, Australia.
| | - Paul R Martin
- The University of Sydney, Save Sight Institute, Faculty of Medicine and Health, Sydney, NSW, 2000, Australia; Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, NSW, 2000, Australia
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23
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Horwitz GD. Temporal information loss in the macaque early visual system. PLoS Biol 2020; 18:e3000570. [PMID: 31971946 PMCID: PMC6977937 DOI: 10.1371/journal.pbio.3000570] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 12/05/2019] [Indexed: 01/09/2023] Open
Abstract
Stimuli that modulate neuronal activity are not always detectable, indicating a loss of information between the modulated neurons and perception. To identify where in the macaque visual system information about periodic light modulations is lost, signal-to-noise ratios were compared across simulated cone photoreceptors, lateral geniculate nucleus (LGN) neurons, and perceptual judgements. Stimuli were drifting, threshold-contrast Gabor patterns on a photopic background. The sensitivity of LGN neurons, extrapolated to populations, was similar to the monkeys' at low temporal frequencies. At high temporal frequencies, LGN sensitivity exceeded the monkeys' and approached the upper bound set by cone photocurrents. These results confirm a loss of high-frequency information downstream of the LGN. However, this loss accounted for only about 5% of the total. Phototransduction accounted for essentially all of the rest. Together, these results show that low temporal frequency information is lost primarily between the cones and the LGN, whereas high-frequency information is lost primarily within the cones, with a small additional loss downstream of the LGN.
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Affiliation(s)
- Gregory D. Horwitz
- Department of Physiology and Biophysics, Washington National Primate Research Center, University of Washington, Seattle, Washington, United States of America
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24
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Ohlemacher SK, Langer KB, Fligor CM, Feder EM, Edler MC, Meyer JS. Advances in the Differentiation of Retinal Ganglion Cells from Human Pluripotent Stem Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1186:121-140. [PMID: 31654388 DOI: 10.1007/978-3-030-28471-8_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Human pluripotent stem cell (hPSC) technology has revolutionized the field of biology through the unprecedented ability to study the differentiation of human cells in vitro. In the past decade, hPSCs have been applied to study development, model disease, develop drugs, and devise cell replacement therapies for numerous biological systems. Of particular interest is the application of this technology to study and treat optic neuropathies such as glaucoma. Retinal ganglion cells (RGCs) are the primary cell type affected in these diseases, and once lost, they are unable to regenerate in adulthood. This necessitates the development of strategies to study the mechanisms of degeneration as well as develop translational therapeutic approaches to treat early- and late-stage disease progression. Numerous protocols have been established to derive RGCs from hPSCs, with the ability to generate large populations of human RGCs for translational applications. In this review, the key applications of hPSCs within the retinal field are described, including the use of these cells as developmental models, disease models, drug development, and finally, cell replacement therapies. In greater detail, the current report focuses on the differentiation of hPSC-derived RGCs and the many unique characteristics associated with these cells in vitro including their genetic identifiers, their electrophysiological activity, and their morphological maturation. Also described is the current progress in the use of patient-specific hPSCs to study optic neuropathies affecting RGCs, with emphasis on the use of these RGCs for studying disease mechanisms and pathogenesis, drug screening, and cell replacement therapies in future studies.
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Affiliation(s)
- Sarah K Ohlemacher
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Kirstin B Langer
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Clarisse M Fligor
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Elyse M Feder
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Michael C Edler
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA.,Department of Medical and Molecular Genetics, Indiana University, Indianapolis, IN, USA
| | - Jason S Meyer
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA. .,Department of Medical and Molecular Genetics, Indiana University, Indianapolis, IN, USA. .,Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN, USA.
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25
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Morny EKA, Patel K, Votruba M, Binns AM, Margrain TH. The Relationship Between the Photopic Negative Response and Retinal Ganglion Cell Topography. Invest Ophthalmol Vis Sci 2019; 60:1879-1887. [PMID: 31042794 DOI: 10.1167/iovs.18-25272] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To assess the topographic relationship between the photopic negative response (PhNR) and retinal ganglion cell distribution in healthy individuals. Method Data was recorded from 16 healthy participants. The amplitude of PhNRs obtained in response to focal long duration (250 ms) and brief flash (5 ms), red (660 nm) on blue (469 nm) stimuli of increasing size (5° - full field) were measured. The number of retinal ganglion cell receptive fields (RGCf) in each stimulus area was established from the literature and regression analysis used to determine the relationships between: PhNR amplitude and number of RGCfs stimulated, PhNR density and the RGCf density and response per RGCf as a function of eccentricity. Results The overall amplitude of the PhNR increased with stimulus size and the response density declined from ∼0.1 μV/deg in the macular region to ∼0.003 μV/deg approximately 45° from the fovea. Contrary to expectations, the relationship between the PhNR and number of RGCf was nonlinear, the response from more eccentric neurons being about three times greater than those in the macular region. Conclusions Although the amplitude of the PhNR broadly maps on to the topographic distribution of RGCf the increase in PhNR amplitude with increasing eccentricity is only partly explained by RGCf numbers. Increases in the PhNR amplitude may be due to topographic variations in the contributions from other non-RGC neurons, as well as eccentricity-related morphologic and physiologic differences in RGCs.
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Affiliation(s)
- Enyam Komla A Morny
- Department of Optometry and Vision Science, University of Cape Coast, Cape Coast, Ghana
| | - Kishan Patel
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Marcela Votruba
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom.,Eye Unit, University Hospital of Wales, Cardiff, Wales, United Kingdom
| | - Alison M Binns
- School of Health Sciences, City, University of London, London, United Kingdom
| | - Tom H Margrain
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom
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26
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Raghuram V, Werginz P, Fried SI. Scaling of the AIS and Somatodendritic Compartments in α S RGCs. Front Cell Neurosci 2019; 13:436. [PMID: 31611777 PMCID: PMC6777007 DOI: 10.3389/fncel.2019.00436] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 09/13/2019] [Indexed: 11/21/2022] Open
Abstract
The anatomical properties of the axon initial segment (AIS) are tailored in certain types of CNS neurons to help optimize different aspects of neuronal function. Here, we questioned whether the AISs of retinal ganglion cells (RGC) were similarly customized, and if so, whether they supported specific RGC functions. To explore this, we measured the AIS properties in alpha sustained RGCs (α S RGCs) of mouse; α S RGCs sizes vary systematically along the nasal temporal axis of the retina, making these cells an attractive population with which to study potential correlations between AIS properties and cell size. Measurements of AIS length as well as distance from the soma revealed that both were scaled to cell size, i.e., cells with large dendritic fields had long AISs that were relatively far from the soma. Within the AIS, the percentage of Na v 1.6 voltage-gated sodium channels remained highly consistent, regardless of cell size or other AIS properties. Although ON RGCs were slightly larger than OFF cells at any given location of the retina, the level of scaling and relative distribution of voltage-gated sodium channels were highly similar. Computational modeling revealed that AIS scaling influenced spiking thresholds, spike rate as well as the kinetics of individual action potentials, Interestingly, the effect of individual features of the AIS varied for different neuronal functions, e.g., AIS length had a larger effect on the efficacy by which the AIS initiated spike triggered the somatic spike than it did on repetitive spiking. The polarity of the effect varied for different properties, i.e., increases to soma size increased spike threshold while increases to AIS length decreased threshold. Thus, variations in the relative level of scaling for individual components could fine tune threshold or other neuronal functions. Light responses were highly consistent across the full range of cell sizes suggesting that scaling may post-synaptically shape response stability, e.g., in addition to several well-known pre-synaptic contributors.
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Affiliation(s)
- Vineeth Raghuram
- Rehabilitation Research & Development Service, Boston VA Healthcare System, Boston, MA, United States
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Paul Werginz
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Institute for Analysis and Scientific Computing, Vienna University of Technology, Vienna, Austria
| | - Shelley I. Fried
- Rehabilitation Research & Development Service, Boston VA Healthcare System, Boston, MA, United States
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
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27
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Abstract
SIGNIFICANCE Central motion perception, as assessed by minimum displacement detection, was reduced in highly myopic eyes. Peripheral motion detection may be influenced by myopia, particularly in the inferior-nasal retina. PURPOSE Motion discrimination is a complex visual task processed mainly via the magnocellular pathway. We investigated whether it is affected in myopia. METHODS Ninety young adults aged 18 to 28 years participated: 30 emmetropes (spherical equivalent refractions +1.00 to -0.50 diopters [D]), 30 low myopes -1.00 to -4.75 D) and 30 higher myopes (<-5 D). Random dot patterns were used to measure motion perception thresholds for minimum displacement (Dmin), maximum displacement (Dmax), and motion coherence tasks. Each task was performed centrally and at four oblique peripheral visual field locations (at 3.65 and 12 degrees for Dmin and Dmax tasks, respectively). Macular retinal thickness was measured with optical coherence tomography. RESULTS The central Dmin task was correlated significantly with refraction (r = -0.303, P = .004) and axial length (r = +0.224, P = .04), and the superior-temporal field Dmin task was correlated significantly with axial length (r = 0.230, P = .04). Higher myopes had poorer performance than emmetropes by 25% (higher values). For the Dmin peripheral task and for Dmax and coherence tasks at both central and peripheral locations, there were no significant correlations with refraction or axial length. At three of four positions, the peripheral Dmin task was correlated significantly with thickness in the corresponding retinal region: superior-temporal Dmin (Pearson r = -0.357, P < .001), inferior-nasal Dmin (r = -0.237, P = .03) and inferior-temporal Dmin (r = -0.233, P = .03). CONCLUSIONS Central motion perception, as assessed by minimum displacement detection, was reduced by 25% in highly myopic eyes. Peripheral motion detection may be influenced by myopia, particularly in the inferior-nasal retina. Retinal stretching due to axial elongation may be linked to reduced performance in higher myopes.
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28
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Rhoades CE, Shah NP, Manookin MB, Brackbill N, Kling A, Goetz G, Sher A, Litke AM, Chichilnisky EJ. Unusual Physiological Properties of Smooth Monostratified Ganglion Cell Types in Primate Retina. Neuron 2019; 103:658-672.e6. [PMID: 31227309 PMCID: PMC6817368 DOI: 10.1016/j.neuron.2019.05.036] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 04/26/2019] [Accepted: 05/22/2019] [Indexed: 02/06/2023]
Abstract
The functions of the diverse retinal ganglion cell types in primates and the parallel visual pathways they initiate remain poorly understood. Here, unusual physiological and computational properties of the ON and OFF smooth monostratified ganglion cells are explored. Large-scale multi-electrode recordings from 48 macaque retinas revealed that these cells exhibit irregular receptive field structure composed of spatially segregated hotspots, quite different from the classic center-surround model of retinal receptive fields. Surprisingly, visual stimulation of different hotspots in the same cell produced spikes with subtly different spatiotemporal voltage signatures, consistent with a dendritic contribution to hotspot structure. Targeted visual stimulation and computational inference demonstrated strong nonlinear subunit properties associated with each hotspot, supporting a model in which the hotspots apply nonlinearities at a larger spatial scale than bipolar cells. These findings reveal a previously unreported nonlinear mechanism in the output of the primate retina that contributes to signaling spatial information.
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Affiliation(s)
- Colleen E Rhoades
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
| | - Nishal P Shah
- Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Michael B Manookin
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA
| | - Nora Brackbill
- Department of Physics, Stanford University, Stanford, CA 94305, USA
| | - Alexandra Kling
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
| | - Georges Goetz
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
| | - Alexander Sher
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Alan M Litke
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - E J Chichilnisky
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Department of Ophthalmology Stanford University, Stanford, CA 94305, USA; Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
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29
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Connectomic Identification and Three-Dimensional Color Tuning of S-OFF Midget Ganglion Cells in the Primate Retina. J Neurosci 2019; 39:7893-7909. [PMID: 31405926 DOI: 10.1523/jneurosci.0778-19.2019] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/27/2019] [Accepted: 08/06/2019] [Indexed: 11/21/2022] Open
Abstract
In the trichromatic primate retina, the "midget" retinal ganglion cell is the classical substrate for red-green color signaling, with a circuitry that enables antagonistic responses between long (L)- and medium (M)-wavelength-sensitive cone inputs. Previous physiological studies showed that some OFF midget ganglion cells may receive sparse input from short (S)-wavelength-sensitive cones, but the effect of S-cone inputs on the chromatic tuning properties of such cells has not been explored. Moreover, anatomical evidence for a synaptic pathway from S cones to OFF midget ganglion cells through OFF midget bipolar cells remains ambiguous. In this study, we address both questions for the macaque monkey retina. First, we used serial block-face electron microscopy to show that every S cone in the parafoveal retina synapses principally with a single OFF midget bipolar cell, which in turn forms a private-line connection with an OFF midget ganglion cell. Second, we used patch electrophysiology to characterize the chromatic tuning of OFF midget ganglion cells in the near peripheral retina that receive combined input from L, M, and S cones. These "S-OFF" midget cells have a characteristic S-cone spatial signature, but demonstrate heterogeneous color properties due to the variable strength of L, M, and S cone input across the receptive field. Together, these findings strongly support the hypothesis that the OFF midget pathway is the major conduit for S-OFF signals in primate retina and redefines the pathway as a chromatically complex substrate that encodes color signals beyond the classically recognized L versus M and S versus L+M cardinal mechanisms.SIGNIFICANCE STATEMENT The first step of color processing in the visual pathway of primates occurs when signals from short (S)-, middle (M)-, and long (L)-wavelength-sensitive cone types interact antagonistically within the retinal circuitry to create color-opponent pathways. The midget (L versus M or "red-green") and small bistratified (S vs L+M, or "blue-yellow") ganglion cell pathways appear to provide the physiological origin of the cardinal axes of human color vision. Here we confirm the presence of an additional S-OFF midget circuit in the macaque monkey fovea with scanning block-face electron microscopy and show physiologically that a subpopulation of S-OFF midget cells combine S, L, and M cone inputs along noncardinal directions of color space, expanding the retinal role in color coding.
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30
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Morphological Cell Types Projecting from V1 Layer 4B to V2 Thick and Thin Stripes. J Neurosci 2019; 39:7501-7512. [PMID: 31358652 DOI: 10.1523/jneurosci.1096-19.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/16/2019] [Accepted: 07/19/2019] [Indexed: 11/21/2022] Open
Abstract
In macaque visual cortex, different cytochrome oxidase stripes of area V2 receive segregated projections from layers (L)2/3 and 4B of the primary visual cortex (V1), and project to dorsal or ventral stream extrastriate areas. Parallel V1-to-V2 pathways suggest functionally specialized circuits, but it is unknown whether these circuits arise from distinct cell types. V1 L4B includes two morphological types of excitatory projection neurons: pyramids, which carry mixed magnocellular (M) and parvocellular (P) information to downstream areas, and spiny stellates, which carry only M information. Previous studies have shown that, overall, V2 receives ∼80% of its L4B inputs from pyramids, thus receiving mixed M and P signals. However, it is unknown how pyramids and stellates distribute their outputs to the different V2 stripes, and whether different stripes receive inputs from morphologically distinct neuron types. Using viral-mediated labeling of V2-projecting L4B neurons in male macaques, we show that thick stripes receive a greater contribution of L4B inputs from M-dominated spiny stellates compared with thin stripes. Both stripe types, however, receive a much larger contribution from spiny stellates than previously shown for V2 overall, indicating that a larger amount of M information than previously thought flows into both the dorsal and ventral streams via the V2 thick and thin stripes, respectively. Moreover, we identify four types of V2-projecting L4B cells differing in size and complexity. Three such cell types project to both thin and thick stripes, but one type, the giant spiny-stellate neuron, resembling L4B neurons projecting to motion-sensitive area MT, was only found to project to thick stripes.SIGNIFICANCE STATEMENT Area V1 partitions visual information into functionally specialized parallel pathways which terminate into distinct stripes of area V2. We asked whether V1 inputs to different V2 stripes arise from morphologically different cell types. V1 layer (L)4B has two cell types: pyramids, which carry both magnocellular (M) and parvocellular (P) visual signals, and spiny stellates, which carry only M signals. We find that V2 thick stripes, which project to areas processing object motion, receive a larger fraction of L4B input from M-dominated stellates compared with thin stripes, which project to areas processing object attributes. We also identify four morphological types of V2-projecting L4B neurons, suggestive of four functionally specialized cell types.
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Linkage between retinal ganglion cell density and the nonuniform spatial integration across the visual field. Proc Natl Acad Sci U S A 2019; 116:3827-3836. [PMID: 30737290 PMCID: PMC6397585 DOI: 10.1073/pnas.1817076116] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The integration of visual information over space is critical to human pattern vision. For either luminance detection or object recognition, the position of the target in the visual field governs the size of a window within which visual information is integrated. Here we analyze the relationship between the topographic distribution of ganglion cell density and the nonuniform spatial integration across the visual field. We find that the variation in the retinal ganglion cell (RGC) density across the human retina is closely matched to the variation in the extent of spatial integration. Our study suggests that a fixed number of RGCs subserves spatial integration of visual input, independent of the visual-field location. The ability to integrate visual information over space is a fundamental component of human pattern vision. Regardless of whether it is for detecting luminance contrast or for recognizing objects in a cluttered scene, the position of the target in the visual field governs the size of a window within which visual information is integrated. Here we analyze the relationship between the topographic distribution of ganglion cell density and the nonuniform spatial integration across the visual field. The extent of spatial integration for luminance detection (Ricco’s area) and object recognition (crowding zone) are measured at various target locations. The number of retinal ganglion cells (RGCs) underlying Ricco’s area or crowding zone is estimated by computing the product of Ricco’s area (or crowding zone) and RGC density for a given target location. We find a quantitative agreement between the behavioral data and the RGC density: The variation in the sampling density of RGCs across the human retina is closely matched to the variation in the extent of spatial integration required for either luminance detection or object recognition. Our empirical data combined with the simulation results of computational models suggest that a fixed number of RGCs subserves spatial integration of visual input, independent of the visual-field location.
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32
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Pathway-Specific Asymmetries between ON and OFF Visual Signals. J Neurosci 2018; 38:9728-9740. [PMID: 30249795 DOI: 10.1523/jneurosci.2008-18.2018] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/08/2018] [Accepted: 09/12/2018] [Indexed: 01/07/2023] Open
Abstract
Visual processing is largely organized into ON and OFF pathways that signal stimulus increments and decrements, respectively. These pathways exhibit natural pairings based on morphological and physiological similarities, such as ON and OFF α-ganglion cells in the mammalian retina. Several studies have noted asymmetries in the properties of ON and OFF pathways. For example, the spatial receptive fields (RFs) of OFF α-cells are systematically smaller than ON α-cells. Analysis of natural scenes suggests that these asymmetries are optimal for visual encoding. To test the generality of ON/OFF asymmetries, we measured the spatiotemporal RF properties of multiple RGC types in rat retina. Through a quantitative and serial classification, we identified three functional pairs of ON and OFF RGCs. We analyzed the structure of their RFs and compared spatial integration, temporal integration, and gain across ON and OFF pairs. Similar to previous results from the cat and primate, RGC types with larger spatial RFs exhibited briefer temporal integration and higher gain. However, each pair of ON and OFF RGC types exhibited distinct asymmetric relationships between RF properties, some of which were opposite to the findings of previous reports. These results reveal the functional organization of six RGC types in the rodent retina and indicate that ON/OFF asymmetries are pathway specific.SIGNIFICANCE STATEMENT Circuits that process sensory input frequently process increments separately from decrements, so-called ON and OFF responses. Theoretical studies indicate that this separation, and associated asymmetries in ON and OFF pathways, may be beneficial for encoding natural stimuli. However, the generality of ON and OFF pathway asymmetries has not been tested. Here we compare the functional properties of three distinct pairs of ON and OFF pathways in the rodent retina and show that their asymmetries are pathway specific. These results provide a new view on the partitioning of vision across diverse ON and OFF signaling pathways.
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33
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Jacoby J, Schwartz GW. Typology and Circuitry of Suppressed-by-Contrast Retinal Ganglion Cells. Front Cell Neurosci 2018; 12:269. [PMID: 30210298 PMCID: PMC6119723 DOI: 10.3389/fncel.2018.00269] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 08/02/2018] [Indexed: 11/13/2022] Open
Abstract
Retinal ganglion cells (RGCs) relay ~40 parallel and independent streams of visual information, each encoding a specific feature of a visual scene, to the brain for further processing. The polarity of a visual neuron’s response to a change in contrast is generally the first characteristic used for functional classification: ON cells increase their spike rate to positive contrast; OFF cells increase their spike rate for negative contrast; ON-OFF cells increase their spike rate for both contrast polarities. Suppressed-by-Contrast (SbC) neurons represent a less well-known fourth category; they decrease firing below a baseline rate for both positive and negative contrasts. SbC RGCs were discovered over 50 years ago, and SbC visual neurons have now been found in the thalamus and primary visual cortex of several mammalian species, including primates. Recent discoveries of SbC RGCs in mice have provided new opportunities for tracing upstream circuits in the retina responsible for the SbC computation and downstream targets in the brain where this information is used. We review and clarify recent work on the circuit mechanism of the SbC computation in these RGCs. Studies of mechanism rely on precisely defined cell types, and we argue that, like ON, OFF, and ON-OFF RGCs, SbC RGCs consist of more than one type. A new appreciation of the diversity of SbC RGCs will help guide future work on their targets in the brain and their roles in visual perception and behavior.
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Affiliation(s)
- Jason Jacoby
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Gregory William Schwartz
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States.,Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Chicago, IL, United States
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34
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Yang CY, Tsai D, Guo T, Dokos S, Suaning GJ, Morley JW, Lovell NH. Differential electrical responses in retinal ganglion cell subtypes: effects of synaptic blockade and stimulating electrode location. J Neural Eng 2018; 15:046020. [PMID: 29737971 DOI: 10.1088/1741-2552/aac315] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Visual prostheses have shown promising results in restoring visual perception to blind patients. The ability to differentially activate retinal ganglion cell (RGC) subtypes could further improve the efficacy of these medical devices. APPROACH Using whole-cell patch clamp, we investigated membrane potential differences between ON and OFF RGCs in the mouse retina when their synaptic inputs were blocked by synaptic blockers, and examined the differences in stimulation thresholds under such conditions. By injecting intracellular current, we further confirmed the relationship between RGC stimulation thresholds and resting membrane potentials (RMPs). In addition, we investigated the effects of stimulating electrode location on the differences in stimulation thresholds between ON and OFF RGCs. MAIN RESULTS With synaptic blockade, ON RGCs became significantly more hyperpolarized (from -61.8 ± 1.4 mV to -70.8 ± 1.6 mV), while OFF RGCs depolarized slightly (from -60.5 ± 0.7 mV to -58.6 ± 0.9 mV). RGC stimulation thresholds were negatively correlated with their RMPs (Pearson r value: -0.5154; p-value: 0.0042). Thus, depriving ON RGCs of synaptic inputs significantly increased their thresholds (from 14.7 ± 1.3 µA to 22.3 ± 2.1 µA) over those of OFF RGCs (from 13.2 ± 0.7 µA to 13.1 ± 1.1 µA). However, with control solution, ON and OFF RGC stimulation thresholds were not significantly different. Finally, placement of the stimulating electrode away from the axon enhanced differences in stimulation thresholds between ON and OFF RGCs, facilitating preferential activation of OFF RGCs. SIGNIFICANCE Since ON and OFF RGCs have antagonistic responses to natural light, achieving differential RGC activation could convey more natural visual information, leading to better visual prosthesis outcomes.
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Affiliation(s)
- Chih Yu Yang
- Graduate School of Biomedical Engineering, UNSW, Sydney, NSW 2052, Australia
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35
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Wolf JE, Arden GB, Plant GT. Selective Damage to Either the “M” Or “P” Cell Pathway in Human Retinal Disease: Implications for Visual Processing. Eur J Ophthalmol 2018; 6:208-14. [PMID: 8823599 DOI: 10.1177/112067219600600221] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Studies in primates have shown there to be 2 main visual afferent pathways (magno and parvo) operating in parallel with different functional roles. Disease state may selectively affect one or other of these, as shown by particular sensory losses. In cases of treated Cuban tropical "neuropathy" (a retinopathy also occurs) visual acuity and achromatic contrast sensitivity are preserved although colour vision is severely affected indicating selective preservation of the "magno" pathway. In Melanoma Associated Retinopathy, red-green colour vision is preserved although achromatic contrast sensitivity for low spatial frequencies, and the detection of motion is damaged suggesting preferential damage to the "magno" pathway. Our studies illuminate two controversial aspects of the P and M systems: the role of type II parvocellular cells in colour vision and the role of M cells in detecting stimuli of low spatial and low temporal frequency.
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Affiliation(s)
- J E Wolf
- Applied Vision Research Centre, City University, London, U.K
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36
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Manookin MB, Patterson SS, Linehan CM. Neural Mechanisms Mediating Motion Sensitivity in Parasol Ganglion Cells of the Primate Retina. Neuron 2018; 97:1327-1340.e4. [PMID: 29503188 PMCID: PMC5866240 DOI: 10.1016/j.neuron.2018.02.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 01/16/2018] [Accepted: 02/02/2018] [Indexed: 10/17/2022]
Abstract
Considerable theoretical and experimental effort has been dedicated to understanding how neural circuits detect visual motion. In primates, much is known about the cortical circuits that contribute to motion processing, but the role of the retina in this fundamental neural computation is poorly understood. Here, we used a combination of extracellular and whole-cell recording to test for motion sensitivity in the two main classes of output neurons in the primate retina-midget (parvocellular-projecting) and parasol (magnocellular-projecting) ganglion cells. We report that parasol, but not midget, ganglion cells are motion sensitive. This motion sensitivity is present in synaptic excitation and disinhibition from presynaptic bipolar cells and amacrine cells, respectively. Moreover, electrical coupling between neighboring bipolar cells and the nonlinear nature of synaptic release contribute to the observed motion sensitivity. Our findings indicate that motion computations arise far earlier in the primate visual stream than previously thought.
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Affiliation(s)
- Michael B Manookin
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA; Vision Science Center, University of Washington, Seattle, WA 98195, USA.
| | - Sara S Patterson
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA; Vision Science Center, University of Washington, Seattle, WA 98195, USA; Graduate Program in Neuroscience, University of Washington, Seattle, WA 98195, USA
| | - Conor M Linehan
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA; Vision Science Center, University of Washington, Seattle, WA 98195, USA
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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.
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Imaging and quantifying ganglion cells and other transparent neurons in the living human retina. Proc Natl Acad Sci U S A 2017; 114:12803-12808. [PMID: 29138314 PMCID: PMC5715765 DOI: 10.1073/pnas.1711734114] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ganglion cells (GCs) are fundamental to retinal neural circuitry, processing photoreceptor signals for transmission to the brain via their axons. However, much remains unknown about their role in vision and their vulnerability to disease leading to blindness. A major bottleneck has been our inability to observe GCs and their degeneration in the living human eye. Despite two decades of development of optical technologies to image cells in the living human retina, GCs remain elusive due to their high optical translucency. Failure of conventional imaging-using predominately singly scattered light-to reveal GCs has led to a focus on multiply-scattered, fluorescence, two-photon, and phase imaging techniques to enhance GC contrast. Here, we show that singly scattered light actually carries substantial information that reveals GC somas, axons, and other retinal neurons and permits their quantitative analysis. We perform morphometry on GC layer somas, including projection of GCs onto photoreceptors and identification of the primary GC subtypes, even beneath nerve fibers. We obtained singly scattered images by: (i) marrying adaptive optics to optical coherence tomography to avoid optical blurring of the eye; (ii) performing 3D subcellular image registration to avoid motion blur; and (iii) using organelle motility inside somas as an intrinsic contrast agent. Moreover, through-focus imaging offers the potential to spatially map individual GCs to underlying amacrine, bipolar, horizontal, photoreceptor, and retinal pigment epithelium cells, thus exposing the anatomical substrate for neural processing of visual information. This imaging modality is also a tool for improving clinical diagnosis and assessing treatment of retinal disease.
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Chandra AJ, Lee SCS, Grünert U. Thorny ganglion cells in marmoset retina: Morphological and neurochemical characterization with antibodies against calretinin. J Comp Neurol 2017; 525:3962-3974. [PMID: 28875500 DOI: 10.1002/cne.24319] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/18/2017] [Accepted: 08/26/2017] [Indexed: 11/06/2022]
Abstract
In primates, over 17 morphological types of retinal ganglion cell have been distinguished by their dendritic morphology and stratification, but reliable markers for specific ganglion cell populations are still rare. The calcium binding protein calretinin is known to be expressed in the inner nuclear and the ganglion cell layer of marmoset retina, however, the specific cell type(s) expressing calretinin in the ganglion cell layer are yet to be determined. Here, we identified calretinin positive retinal ganglion cells in the common marmoset Callithrix jacchus. Double labeling with the ganglion cell marker RBPMS demonstrated that the large majority (80%) of the calretinin positive cells in the ganglion cell layer are ganglion cells, and 20% are displaced amacrine cells. The calretinin positive ganglion cells made up on average 12% of the total ganglion cell population outside of the foveal region and their proportion increased with eccentricity. Prelabeling with antibodies against calretinin and subsequent intracellular injection with DiI revealed that the large majority of the injected cells (n = 74) were either narrow thorny or broad thorny ganglion cells, 14 cells were displaced amacrine cells. Narrow thorny cells were further distinguished into outer and inner stratifying cells. In addition, weakly labeled cells with a large soma were identified as parasol ganglion cells. Our results show that three types of thorny ganglion cells in marmoset retina can be identified with antibodies against calretinin. Our findings are also consistent with the idea that the proportion of wide-field ganglion cell types increases in peripheral retina.
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Affiliation(s)
- Ashleigh J Chandra
- Department of Clinical Ophthalmology, Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, New South Wales, 2000, Australia
| | - Sammy C S Lee
- Department of Clinical Ophthalmology, Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, New South Wales, 2000, Australia
| | - Ulrike Grünert
- Department of Clinical Ophthalmology, Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, New South Wales, 2000, Australia.,Discipline of Anatomy & Histology, School of Medical Sciences, The University of Sydney, Sydney, New South Wales, 2000, Australia
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40
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Abstract
Purpose Peripheral resolution acuity depends on the orientation of the stimuli. However, it is uncertain if such a meridional effect also exists for peripheral detection tasks because they are affected by optical errors. Knowledge of the quantitative differences in acuity for different grating orientations is crucial for choosing the appropriate stimuli for evaluations of peripheral resolution and detection tasks. We assessed resolution and detection thresholds for different grating orientations in the peripheral visual field. Methods Resolution and detection thresholds were evaluated for gratings of four different orientations in eight different visual field meridians in the 20-deg visual field in white light. Detection measurements in monochromatic light (543 nm; bandwidth, 10 nm) were also performed to evaluate the effects of chromatic aberration on the meridional effect. A combination of trial lenses and adaptive optics system was used to correct the monochromatic lower- and higher-order aberrations. Results For both resolution and detection tasks, gratings parallel to the visual field meridian had better threshold compared with the perpendicular gratings, whereas the two oblique gratings had similar thresholds. The parallel and perpendicular grating acuity differences for resolution and detection tasks were 0.16 logMAR and 0.11 logMAD, respectively. Elimination of chromatic errors did not affect the meridional preference in detection acuity. Conclusions Similar to peripheral resolution, detection also shows a meridional effect that appears to have a neural origin. The threshold difference seen for parallel and perpendicular gratings suggests the use of two oblique gratings as stimuli in alternative forced-choice procedures for peripheral vision evaluation to reduce measurement variation.
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41
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Variations in crowding, saccadic precision, and spatial localization reveal the shared topology of spatial vision. Proc Natl Acad Sci U S A 2017; 114:E3573-E3582. [PMID: 28396415 DOI: 10.1073/pnas.1615504114] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Visual sensitivity varies across the visual field in several characteristic ways. For example, sensitivity declines sharply in peripheral (vs. foveal) vision and is typically worse in the upper (vs. lower) visual field. These variations can affect processes ranging from acuity and crowding (the deleterious effect of clutter on object recognition) to the precision of saccadic eye movements. Here we examine whether these variations can be attributed to a common source within the visual system. We first compared the size of crowding zones with the precision of saccades using an oriented clock target and two adjacent flanker elements. We report that both saccade precision and crowded-target reports vary idiosyncratically across the visual field with a strong correlation across tasks for all participants. Nevertheless, both group-level and trial-by-trial analyses reveal dissociations that exclude a common representation for the two processes. We therefore compared crowding with two measures of spatial localization: Landolt-C gap resolution and three-dot bisection. Here we observe similar idiosyncratic variations with strong interparticipant correlations across tasks despite considerably finer precision. Hierarchical regression analyses further show that variations in spatial precision account for much of the variation in crowding, including the correlation between crowding and saccades. Altogether, we demonstrate that crowding, spatial localization, and saccadic precision show clear dissociations, indicative of independent spatial representations, whilst nonetheless sharing idiosyncratic variations in spatial topology. We propose that these topological idiosyncrasies are established early in the visual system and inherited throughout later stages to affect a range of higher-level representations.
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42
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Masri RA, Percival KA, Koizumi A, Martin PR, Grünert U. Survey of retinal ganglion cell morphology in marmoset. J Comp Neurol 2017; 527:236-258. [PMID: 27997691 DOI: 10.1002/cne.24157] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 11/09/2016] [Accepted: 11/09/2016] [Indexed: 01/05/2023]
Abstract
In primate retina, the midget, parasol, and small bistratified cell populations form the large majority of ganglion cells. In addition, there is a variety of low-density wide-field ganglion cell types that are less well characterized. Here we studied retinal ganglion cells in the common marmoset, Callithrix jacchus, using particle-mediated gene transfer. Ganglion cells were transfected with an expression plasmid for the postsynaptic density 95-green fluorescent protein. The retinas were processed with established immunohistochemical markers for bipolar and/or amacrine cells to determine ganglion cell dendritic stratification. In total over 500 ganglion cells were classified based on their dendritic field size, morphology, and stratification in the inner plexiform layer. Over 17 types were distinguished, including midget, parasol, broad thorny, small bistratified, large bistratified, recursive bistratified, recursive monostratified, narrow thorny, smooth monostratified, large sparse, giant sparse (melanopsin) ganglion cells, and a group that may contain several as yet uncharacterized types. Assuming each characterized type forms a hexagonal mosaic, the midget and parasol cells account for over 80% of all ganglion cells in the central retina but only ∼50% of cells in the peripheral (>2 mm) retina. We conclude that the fovea is dominated by midget and parasol cells, but outside the fovea the ganglion cell diversity in marmoset is likely as great as that reported for nonprimate retinas. Taken together, the ganglion cell types in marmoset retina resemble those described previously in macaque retina with respect to morphology, stratification, and change in proportion across the retina.
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Affiliation(s)
- Rania A Masri
- Save Sight Institute and Department of Clinical Ophthalmology, The University of Sydney, Sydney, New South Wales, Australia
| | - Kumiko A Percival
- Save Sight Institute and Department of Clinical Ophthalmology, The University of Sydney, Sydney, New South Wales, Australia
| | - Amane Koizumi
- National Institutes of Natural Sciences, Tokyo, Japan
| | - Paul R Martin
- Save Sight Institute and Department of Clinical Ophthalmology, The University of Sydney, Sydney, New South Wales, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, New South Wales, Australia.,School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Ulrike Grünert
- Save Sight Institute and Department of Clinical Ophthalmology, The University of Sydney, Sydney, New South Wales, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, New South Wales, Australia.,School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia
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43
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Imaging individual neurons in the retinal ganglion cell layer of the living eye. Proc Natl Acad Sci U S A 2017; 114:586-591. [PMID: 28049835 DOI: 10.1073/pnas.1613445114] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Although imaging of the living retina with adaptive optics scanning light ophthalmoscopy (AOSLO) provides microscopic access to individual cells, such as photoreceptors, retinal pigment epithelial cells, and blood cells in the retinal vasculature, other important cell classes, such as retinal ganglion cells, have proven much more challenging to image. The near transparency of inner retinal cells is advantageous for vision, as light must pass through them to reach the photoreceptors, but it has prevented them from being directly imaged in vivo. Here we show that the individual somas of neurons within the retinal ganglion cell (RGC) layer can be imaged with a modification of confocal AOSLO, in both monkeys and humans. Human images of RGC layer neurons did not match the quality of monkey images for several reasons, including safety concerns that limited the light levels permissible for human imaging. We also show that the same technique applied to the photoreceptor layer can resolve ambiguity about cone survival in age-related macular degeneration. The capability to noninvasively image RGC layer neurons in the living eye may one day allow for a better understanding of diseases, such as glaucoma, and accelerate the development of therapeutic strategies that aim to protect these cells. This method may also prove useful for imaging other structures, such as neurons in the brain.
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44
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Oga T, Okamoto T, Fujita I. Basal Dendrites of Layer-III Pyramidal Neurons do not Scale with Changes in Cortical Magnification Factor in Macaque Primary Visual Cortex. Front Neural Circuits 2016; 10:74. [PMID: 27708563 PMCID: PMC5030257 DOI: 10.3389/fncir.2016.00074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 09/08/2016] [Indexed: 11/13/2022] Open
Abstract
Neurons in the mammalian primary visual cortex (V1) are systematically arranged across the cortical surface according to the location of their receptive fields (RFs), forming a visuotopic (or retinotopic) map. Within this map, the foveal visual field is represented by a large cortical surface area, with increasingly peripheral visual fields gradually occupying smaller cortical areas. Although cellular organization in the retina, such as the spatial distribution of ganglion cells, can partially account for the eccentricity-dependent differences in the size of cortical representation, whether morphological differences exist across V1 neurons representing different eccentricities is unclear. In particular, morphological differences in dendritic field diameter might contribute to the magnified representation of the central visual field. Here, we addressed this question by measuring the basal dendritic arbors of pyramidal neurons of layer-IIIC and adjoining layer III sublayers (in the Hassler's nomenclature) in macaque V1. We labeled layer-III pyramidal neurons at various retinotopic positions in V1 by injecting lightly fixed brain tissue with intracellular dye, and then compared dendritic morphology across regions in the retinotopic map representing 0-20° of eccentricity. The dendritic field area, total dendritic length, number of principal dendrites, branching complexity, spine density and total number of spines were all consistent across different retinotopic regions of V1. These results indicate that dendrites in layer-III pyramidal neurons are relatively homogeneous according to these morphometric parameters irrespective of their locations in this portion of the retinotopic map. The homogeneity of dendritic morphology in these neurons suggests that the emphasis of central visual field representation is not attributable to changes in the basal dendritic arbors of pyramidal neurons in layer III, but is likely the result of successive processes earlier in the retino-geniculo-striate pathway.
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Affiliation(s)
- Tomofumi Oga
- Graduate School of Frontier Biosciences, Osaka UniversitySuita, Osaka, Japan
| | - Tsuguhisa Okamoto
- Graduate School of Frontier Biosciences, Osaka UniversitySuita, Osaka, Japan
| | - Ichiro Fujita
- Graduate School of Frontier Biosciences, Osaka UniversitySuita, Osaka, Japan
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology and Osaka UniversitySuita, Osaka, Japan
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45
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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.
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Affiliation(s)
- Peter H Schiller
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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46
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Rousso DL, Qiao M, Kagan RD, Yamagata M, Palmiter RD, Sanes JR. Two Pairs of ON and OFF Retinal Ganglion Cells Are Defined by Intersectional Patterns of Transcription Factor Expression. Cell Rep 2016; 15:1930-44. [PMID: 27210758 DOI: 10.1016/j.celrep.2016.04.069] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 03/15/2016] [Accepted: 04/20/2016] [Indexed: 11/26/2022] Open
Abstract
Visual information is conveyed to the brain by axons of >30 retinal ganglion cell (RGC) types. Characterization of these types is a prerequisite to understanding visual perception. Here, we identify a family of RGCs that we call F-RGCs on the basis of expression of the transcription factor Foxp2. Intersectional expression of Foxp1 and Brn3 transcription factors divides F-RGCs into four types, comprising two pairs, each composed of closely related cells. One pair, F-mini(ON) and F-mini(OFF), shows robust direction selectivity. They are among the smallest RGCs in the mouse retina. The other pair, F-midi(ON) and F-midi(OFF), is larger and not direction selective. Together, F-RGCs comprise >20% of RGCs in the mouse retina, halving the number that remain to be classified and doubling the number of known direction-selective cells. Co-expression of Foxp and Brn3 genes also marks subsets of RGCs in macaques that could be primate homologs of F-RGCs.
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Affiliation(s)
- David L Rousso
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | - Mu Qiao
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | - Ruth D Kagan
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | - Masahito Yamagata
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | - Richard D Palmiter
- HHMI and Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Joshua R Sanes
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA.
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47
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Denman DJ, Contreras D. On Parallel Streams through the Mouse Dorsal Lateral Geniculate Nucleus. Front Neural Circuits 2016; 10:20. [PMID: 27065811 PMCID: PMC4811935 DOI: 10.3389/fncir.2016.00020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 03/08/2016] [Indexed: 12/12/2022] Open
Abstract
The mouse visual system is an emerging model for the study of cortical and thalamic circuit function. To maximize the usefulness of this model system, it is important to analyze the similarities and differences between the organization of all levels of the murid visual system with other, better studied systems (e.g., non-human primates and the domestic cat). While the understanding of mouse retina and cortex has expanded rapidly, less is known about mouse dorsal lateral geniculate nucleus (dLGN). Here, we study whether parallel processing streams exist in mouse dLGN. We use a battery of stimuli that have been previously shown to successfully distinguish parallel streams in other species: electrical stimulation of the optic chiasm, contrast-reversing stationary gratings at varying spatial phase, drifting sinusoidal gratings, dense noise for receptive field reconstruction, and frozen contrast-modulating noise. As in the optic nerves of domestic cats and non-human primates, we find evidence for multiple conduction velocity groups after optic chiasm stimulation. As in so-called “visual mammals”, we find a subpopulation of mouse dLGN cells showing non-linear spatial summation. However, differences in stimulus selectivity and sensitivity do not provide sufficient basis for identification of clearly distinct classes of relay cells. Nevertheless, consistent with presumptively homologous status of dLGNs of all mammals, there are substantial similarities between response properties of mouse dLGN neurons and those of cats and primates.
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Affiliation(s)
| | - Diego Contreras
- Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
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48
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de Souza CF, Nivison-Smith L, Christie DL, Polkinghorne P, McGhee C, Kalloniatis M, Acosta ML. Macromolecular markers in normal human retina and applications to human retinal disease. Exp Eye Res 2016; 150:135-48. [PMID: 26769220 DOI: 10.1016/j.exer.2016.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 12/23/2015] [Accepted: 01/04/2016] [Indexed: 01/04/2023]
Abstract
Macromolecular cell markers are essential for the classification and characterization of the highly complex and cellularly diverse vertebrate retina. Although a plethora of markers are described in the current literature, the immunoreactivity of these markers in normal human tissue has not been fully determined. This is problematic as they are quintessential to the characterization of morphological changes associated with human retinal disease. This review provides an overview of the macromolecular markers currently available to assess human retinal cell types. We draw on immunohistochemical studies conducted in our laboratories to describe marker immunoreactivity in human retina alongside comparative descriptions in non-human tissues. Considering the growing number of eye banks services offering healthy and diseased human retinal tissue, this review provides a point of reference for future human retina studies and highlights key species specific disease applications of some macromolecular markers.
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Affiliation(s)
- Clairton F de Souza
- School of Optometry and Vision Science, University of Auckland, Auckland, 1023, New Zealand; Department of Ophthalmology, University of Auckland, Auckland, 1023, New Zealand
| | - Lisa Nivison-Smith
- Centre for Eye Health, University of New South Wales, Sydney, 2052, Australia; School of Optometry and Vision Science, University of New South Wales, Sydney, 2052, Australia
| | - David L Christie
- School of Biological Sciences, University of Auckland, Auckland, 1023, New Zealand
| | - Phillip Polkinghorne
- Department of Ophthalmology, University of Auckland, Auckland, 1023, New Zealand; New Zealand National Eye Centre, University of Auckland, Auckland, 1023, New Zealand
| | - Charles McGhee
- Department of Ophthalmology, University of Auckland, Auckland, 1023, New Zealand; New Zealand National Eye Centre, University of Auckland, Auckland, 1023, New Zealand
| | - Michael Kalloniatis
- School of Optometry and Vision Science, University of Auckland, Auckland, 1023, New Zealand; Centre for Eye Health, University of New South Wales, Sydney, 2052, Australia; School of Optometry and Vision Science, University of New South Wales, Sydney, 2052, Australia
| | - Monica L Acosta
- School of Optometry and Vision Science, University of Auckland, Auckland, 1023, New Zealand; New Zealand National Eye Centre, University of Auckland, Auckland, 1023, New Zealand.
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49
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Dhande OS, Stafford BK, Lim JHA, Huberman AD. Contributions of Retinal Ganglion Cells to Subcortical Visual Processing and Behaviors. Annu Rev Vis Sci 2015; 1:291-328. [PMID: 28532372 DOI: 10.1146/annurev-vision-082114-035502] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Every aspect of visual perception and behavior is built from the neural activity of retinal ganglion cells (RGCs), the output neurons of the eye. Here, we review progress toward understanding the many types of RGCs that communicate visual signals to the brain, along with the subcortical brain regions that use those signals to build and respond to representations of the outside world. We emphasize recent progress in the use of mouse genetics, viral circuit tracing, and behavioral psychophysics to define and map the various RGCs and their associated networks. We also address questions about the homology of RGC types in mice and other species including nonhuman primates and humans. Finally, we propose a framework for understanding RGC typology and for highlighting the relationship between RGC type-specific circuitry and the processing stations in the brain that support and give rise to the perception of sight.
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Affiliation(s)
- Onkar S Dhande
- Neurosciences Department, Neurobiology Section in the Division of Biological Sciences, and Department of Ophthalmology, University of California, San Diego, La Jolla, California 92093; ,
| | - Benjamin K Stafford
- Neurosciences Department, Neurobiology Section in the Division of Biological Sciences, and Department of Ophthalmology, University of California, San Diego, La Jolla, California 92093; ,
| | - Jung-Hwan A Lim
- Neurosciences Department, Neurobiology Section in the Division of Biological Sciences, and Department of Ophthalmology, University of California, San Diego, La Jolla, California 92093; ,
| | - Andrew D Huberman
- Neurosciences Department, Neurobiology Section in the Division of Biological Sciences, and Department of Ophthalmology, University of California, San Diego, La Jolla, California 92093; ,
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50
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Masri RA, Percival KA, Koizumi A, Martin PR, Grünert U. Connectivity between the OFF bipolar type DB3a and six types of ganglion cell in the marmoset retina. J Comp Neurol 2015; 524:1839-58. [PMID: 26559914 DOI: 10.1002/cne.23925] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/12/2015] [Accepted: 11/09/2015] [Indexed: 12/31/2022]
Abstract
Parallel visual pathways originate at the first synapse in the retina, where cones make connections with cone bipolar cells that in turn contact ganglion cells. There are more ganglion cell types than bipolar types, suggesting that there must be divergence from bipolar to ganglion cells. Here we analyze the contacts between an OFF bipolar type (DB3a) and six ganglion cell types in the retina of the marmoset monkey (Callithrix jacchus). Ganglion cells were transfected via particle-mediated gene transfer of an expression plasmid for the postsynaptic density 95-green fluorescent protein (PSD95-GFP), and DB3a cells were labeled via immunohistochemistry. Ganglion cell types that fully or partially costratified with DB3a cells included OFF parasol, OFF midget, broad thorny, recursive bistratified, small bistratified, and large bistratified cells. On average, the number of DB3a contacts to parasol cells (18 contacts per axon terminal) is higher than that to other ganglion cell types (between four and seven contacts). We estimate that the DB3a output to OFF parasol cells accounts for at least 30% of the total DB3a output. Furthermore, we found that OFF parasol cells receive approximately 20% of their total bipolar input from DB3a cells, suggesting that other diffuse bipolar types also provide input to OFF parasol cells. We conclude that DB3a cells preferentially contact OFF parasol cells but also provide input to other ganglion cell types.
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Affiliation(s)
- Rania A Masri
- Department of Ophthalmology and Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia
| | - Kumiko A Percival
- Department of Ophthalmology and Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia
| | - Amane Koizumi
- National Institutes of Natural Sciences, Tokyo, Japan
| | - Paul R Martin
- Department of Ophthalmology and Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, New South Wales, 2000, Australia.,School of Medical Sciences, The University of Sydney, Sydney, New South Wales, 2000, Australia
| | - Ulrike Grünert
- Department of Ophthalmology and Save Sight Institute, The University of Sydney, Sydney, New South Wales, 2000, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, New South Wales, 2000, Australia.,School of Medical Sciences, The University of Sydney, Sydney, New South Wales, 2000, Australia
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