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Di Tullio RW, Wei L, Balasubramanian V. Slow and steady: auditory features for discriminating animal vocalizations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599962. [PMID: 39005308 PMCID: PMC11244870 DOI: 10.1101/2024.06.20.599962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
We propose that listeners can use temporal regularities - spectro-temporal correlations that change smoothly over time - to discriminate animal vocalizations within and between species. To test this idea, we used Slow Feature Analysis (SFA) to find the most temporally regular components of vocalizations from birds (blue jay, house finch, American yellow warbler, and great blue heron), humans (English speakers), and rhesus macaques. We projected vocalizations into the learned feature space and tested intra-class (same speaker/species) and inter-class (different speakers/species) auditory discrimination by a trained classifier. We found that: 1) Vocalization discrimination was excellent (> 95%) in all cases; 2) Performance depended primarily on the ~10 most temporally regular features; 3) Most vocalizations are dominated by ~10 features with high temporal regularity; and 4) These regular features are highly correlated with the most predictable components of animal sounds.
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Affiliation(s)
- Ronald W Di Tullio
- David Rittenhouse Laboratory, Department of Physics and Astronomy, University of Pennsylvania, USA
- Computational Neuroscience Initiative, University of Pennsylvania, USA
| | - Linran Wei
- David Rittenhouse Laboratory, Department of Physics and Astronomy, University of Pennsylkvania, USA
| | - Vijay Balasubramanian
- David Rittenhouse Laboratory, Department of Physics and Astronomy, University of Pennsylvania, USA
- Computational Neuroscience Initiative, University of Pennsylvania, USA
- Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
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2
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Wu N, Zhou B, Agrochao M, Clark DA. Broken time reversal symmetry in visual motion detection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.08.598068. [PMID: 38915608 PMCID: PMC11195140 DOI: 10.1101/2024.06.08.598068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Our intuition suggests that when a movie is played in reverse, our perception of motion in the reversed movie will be perfectly inverted compared to the original. This intuition is also reflected in many classical theoretical and practical models of motion detection. However, here we demonstrate that this symmetry of motion perception upon time reversal is often broken in real visual systems. In this work, we designed a set of visual stimuli to investigate how stimulus symmetries affect time reversal symmetry breaking in the fruit fly Drosophila's well-studied optomotor rotation behavior. We discovered a suite of new stimuli with a wide variety of different properties that can lead to broken time reversal symmetries in fly behavioral responses. We then trained neural network models to predict the velocity of scenes with both natural and artificial contrast distributions. Training with naturalistic contrast distributions yielded models that break time reversal symmetry, even when the training data was time reversal symmetric. We show analytically and numerically that the breaking of time reversal symmetry in the model responses can arise from contrast asymmetry in the training data, but can also arise from other features of the contrast distribution. Furthermore, shallower neural network models can exhibit stronger symmetry breaking than deeper ones, suggesting that less flexible neural networks promote some forms of time reversal symmetry breaking. Overall, these results reveal a surprising feature of biological motion detectors and suggest that it could arise from constrained optimization in natural environments.
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Affiliation(s)
- Nathan Wu
- Yale College, New Haven, CT 06511, USA
| | - Baohua Zhou
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Margarida Agrochao
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Damon A. Clark
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
- Department of Physics, Yale University, New Haven, CT 06511, USA
- Department of Neuroscience, Yale University, New Haven, CT 06511, USA
- Quantitative Biology Institute, Yale University, New Haven, CT 06511, USA
- Wu Tsai Institute, Yale University, New Haven, CT 06511, USA
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3
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Shi Y, Eskew RT. Asymmetries between achromatic increments and decrements: Perceptual scales and discrimination thresholds. J Vis 2024; 24:10. [PMID: 38607638 PMCID: PMC11019583 DOI: 10.1167/jov.24.4.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 02/16/2024] [Indexed: 04/13/2024] Open
Abstract
The perceptual response to achromatic incremental (A+) and decremental (A-) visual stimuli is known to be asymmetrical, due most likely to differences between ON and OFF channels. In the current study, we further investigated this asymmetry psychophysically. In Experiment 1, maximum likelihood difference scaling (MLDS) was used to estimate separately observers' perceptual scales for A+ and A-. In Experiment 2, observers performed two spatial alternative forced choice (2SAFC) pedestal discrimination on multiple pedestal contrast levels, using all combinations of A+ and A- pedestals and tests. Both experiments showed the well-known asymmetry. The perceptual scale curves of A+ follow a modified Naka-Rushton equation, whereas those of A- follow a cubic function. Correspondingly, the discrimination thresholds for the A+ pedestal increased monotonically with pedestal contrast, whereas the thresholds of the A- pedestal first increased as the pedestal contrast increased, then decreased as the contrast became higher. We propose a model that links the results of the two experiments, in which the pedestal discrimination threshold is inversely related to the derivative of the perceptual scale curve. Our findings generally agree with Whittle's previous findings (Whittle, 1986, 1992), which also included strong asymmetry between A+ and A-. We suggest that the perception of achromatic balanced incremental and decremental (bipolar) stimuli, such as gratings or flicker, might be dominated by one polarity due to this asymmetry under some conditions.
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Affiliation(s)
- Yangyi Shi
- Department of Psychology, Northeastern University, Boston, MA, USA
- yangyishi.com
| | - Rhea T Eskew
- Department of Psychology, Northeastern University, Boston, MA, USA
- https://web.northeastern.edu/visionlab/
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4
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Hsiang JC, Shen N, Soto F, Kerschensteiner D. Distributed feature representations of natural stimuli across parallel retinal pathways. Nat Commun 2024; 15:1920. [PMID: 38429280 PMCID: PMC10907388 DOI: 10.1038/s41467-024-46348-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: 08/10/2023] [Accepted: 02/22/2024] [Indexed: 03/03/2024] Open
Abstract
How sensory systems extract salient features from natural environments and organize them across neural pathways is unclear. Combining single-cell and population two-photon calcium imaging in mice, we discover that retinal ON bipolar cells (second-order neurons of the visual system) are divided into two blocks of four types. The two blocks distribute temporal and spatial information encoding, respectively. ON bipolar cell axons co-stratify within each block, but separate laminarly between them (upper block: diverse temporal, uniform spatial tuning; lower block: diverse spatial, uniform temporal tuning). ON bipolar cells extract temporal and spatial features similarly from artificial and naturalistic stimuli. In addition, they differ in sensitivity to coherent motion in naturalistic movies. Motion information is distributed across ON bipolar cells in the upper and the lower blocks, multiplexed with temporal and spatial contrast, independent features of natural scenes. Comparing the responses of different boutons within the same arbor, we find that axons of all ON bipolar cell types function as computational units. Thus, our results provide insights into the visual feature extraction from naturalistic stimuli and reveal how structural and functional organization cooperate to generate parallel ON pathways for temporal and spatial information in the mammalian retina.
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Affiliation(s)
- Jen-Chun Hsiang
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Ning Shen
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Florentina Soto
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Daniel Kerschensteiner
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA.
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, 63110, USA.
- Department of Biomedical Engineering, Washington University School of Medicine, St. Louis, MO, 63110, USA.
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5
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Maehara G, Wang Y, Murakami I. Effects of binocular disparity on binocular luminance combination. J Vis 2024; 24:4. [PMID: 38376853 PMCID: PMC10883336 DOI: 10.1167/jov.24.2.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024] Open
Abstract
This study aimed to examine the effects of binocular disparity on binocular combination of brightness information coming from luminance increments and decrements. The point of subjective equality was determined by asking the observers to judge which stimulus appeared brighter-a bar stimulus with variable disparity or another stimulus with zero disparity. For the bar stimulus, the interocular luminance ratio was varied to trace an equal brightness curve. Binocular disparity had no effect on luminance increments presented on a gray or black background. In contrast, when luminance decrements were presented on a gray background, non-zero disparities elevated points of subjective equality for stimuli with interocular luminance differences. This means that the binocular brightness combination of the two monocular signals shifted from winner-take-all summation toward linear averaging. It has been argued that this effect may be caused by non-zero binocular disparities attenuating interocular suppression, which is deemed to operate normally with zero disparity.
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Affiliation(s)
- Goro Maehara
- Department of Human Science, Kanagawa University, Kanagawa, Japan
| | - Yiqian Wang
- Department of Psychology, The University of Tokyo, Tokyo, Japan
| | - Ikuya Murakami
- Department of Psychology, The University of Tokyo, Tokyo, Japan
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6
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Poudel S, Jin J, Rahimi-Nasrabadi H, Dellostritto S, Dul MW, Viswanathan S, Alonso JM. Contrast Sensitivity of ON and OFF Human Retinal Pathways in Myopia. J Neurosci 2024; 44:e1487232023. [PMID: 38050109 PMCID: PMC10860621 DOI: 10.1523/jneurosci.1487-23.2023] [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: 08/07/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 12/06/2023] Open
Abstract
The human visual cortex processes light and dark stimuli with ON and OFF pathways that are differently modulated by luminance contrast. We have previously demonstrated that ON cortical pathways have higher contrast sensitivity than OFF cortical pathways and the difference increases with luminance range (defined as the maximum minus minimum luminance in the scene). Here, we demonstrate that these ON-OFF cortical differences are already present in the human retina and that retinal responses measured with electroretinography are more affected by reductions in luminance range than cortical responses measured with electroencephalography. Moreover, we show that ON-OFF pathway differences measured with electroretinography become more pronounced in myopia, a visual disorder that elongates the eye and blurs vision at far distance. We find that, as the eye axial length increases across subjects, ON retinal pathways become less responsive, slower in response latency, less sensitive, and less effective and slower at driving pupil constriction. Based on these results, we conclude that myopia is associated with a deficit in ON pathway function that decreases the ability of the retina to process low contrast and regulate retinal illuminance in bright environments.
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Affiliation(s)
- Sabina Poudel
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
| | - Jianzhong Jin
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
| | - Hamed Rahimi-Nasrabadi
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
| | - Stephen Dellostritto
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
| | - Mitchell W Dul
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
| | - Suresh Viswanathan
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
| | - Jose-Manuel Alonso
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, New York 10036
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7
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Chen J, Gish CM, Fransen JW, Salazar-Gatzimas E, Clark DA, Borghuis BG. Direct comparison reveals algorithmic similarities in fly and mouse visual motion detection. iScience 2023; 26:107928. [PMID: 37810236 PMCID: PMC10550730 DOI: 10.1016/j.isci.2023.107928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/07/2023] [Accepted: 09/12/2023] [Indexed: 10/10/2023] Open
Abstract
Evolution has equipped vertebrates and invertebrates with neural circuits that selectively encode visual motion. While similarities in the computations performed by these circuits in mouse and fruit fly have been noted, direct experimental comparisons have been lacking. Because molecular mechanisms and neuronal morphology in the two species are distinct, we directly compared motion encoding in these two species at the algorithmic level, using matched stimuli and focusing on a pair of analogous neurons, the mouse ON starburst amacrine cell (ON SAC) and Drosophila T4 neurons. We find that the cells share similar spatiotemporal receptive field structures, sensitivity to spatiotemporal correlations, and tuning to sinusoidal drifting gratings, but differ in their responses to apparent motion stimuli. Both neuron types showed a response to summed sinusoids that deviates from models for motion processing in these cells, underscoring the similarities in their processing and identifying response features that remain to be explained.
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Affiliation(s)
- Juyue Chen
- Interdepartmental Neurosciences Program, Yale University, New Haven, CT 06511, USA
| | - Caitlin M Gish
- Department of Physics, Yale University, New Haven, CT 06511, USA
| | - James W Fransen
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY 40202, USA
| | | | - Damon A Clark
- Interdepartmental Neurosciences Program, Yale University, New Haven, CT 06511, USA
- Department of Physics, Yale University, New Haven, CT 06511, USA
- Department of Molecular, Cellular, Developmental Biology, Yale University, New Haven, CT 06511, USA
- Department of Neuroscience, Yale University, New Haven, CT 06511, USA
| | - Bart G Borghuis
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY 40202, USA
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Dai W, Wang T, Li Y, Yang Y, Zhang Y, Kang J, Wu Y, Yu H, Xing D. Dynamic Recruitment of the Feedforward and Recurrent Mechanism for Black-White Asymmetry in the Primary Visual Cortex. J Neurosci 2023; 43:5668-5684. [PMID: 37487737 PMCID: PMC10401654 DOI: 10.1523/jneurosci.0168-23.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 07/11/2023] [Accepted: 07/14/2023] [Indexed: 07/26/2023] Open
Abstract
Black and white information is asymmetrically distributed in natural scenes, evokes asymmetric neuronal responses, and causes asymmetric perceptions. Recognizing the universality and essentiality of black-white asymmetry in visual information processing, the neural substrates for black-white asymmetry remain unclear. To disentangle the role of the feedforward and recurrent mechanisms in the generation of cortical black-white asymmetry, we recorded the V1 laminar responses and LGN responses of anesthetized cats of both sexes. In a cortical column, we found that black-white asymmetry starts at the input layer and becomes more pronounced in the output layer. We also found distinct dynamics of black-white asymmetry between the output layer and the input layer. Specifically, black responses dominate in all layers after stimulus onset. After stimulus offset, black and white responses are balanced in the input layer, but black responses still dominate in the output layer. Compared with that in the input layer, the rebound response in the output layer is significantly suppressed. The relative suppression strength evoked by white stimuli is notably stronger and depends on the location within the ON-OFF cortical map. A model with delayed and polarity-selective cortical suppression explains black-white asymmetry in the output layer, within which prominent recurrent connections are identified by Granger causality analysis. In addition to black-white asymmetry in response strength, the interlaminar differences in spatial receptive field varied dynamically. Our findings suggest that the feedforward and recurrent mechanisms are dynamically recruited for the generation of black-white asymmetry in V1.SIGNIFICANCE STATEMENT Black-white asymmetry is universal and essential in visual information processing, yet the neural substrates for cortical black-white asymmetry remain unknown. Leveraging V1 laminar recordings, we provided the first laminar pattern of black-white asymmetry in cat V1 and found distinct dynamics of black-white asymmetry between the output layer and the input layer. Comparing black-white asymmetry across three visual hierarchies, the LGN, V1 input layer, and V1 output layer, we demonstrated that the feedforward and recurrent mechanisms are dynamically recruited for the generation of cortical black-white asymmetry. Our findings not only enhance our understanding of laminar processing within a cortical column but also elucidate how feedforward connections and recurrent connections interact to shape neuronal response properties.
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Affiliation(s)
- Weifeng Dai
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Tian Wang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
- College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yang Li
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Yi Yang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Yange Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Jian Kang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Yujie Wu
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Hongbo Yu
- School of Life Sciences, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200438, China
| | - Dajun Xing
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
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Cai LT, Krishna VS, Hladnik TC, Guilbeault NC, Vijayakumar C, Arunachalam M, Juntti SA, Arrenberg AB, Thiele TR, Cooper EA. Spatiotemporal visual statistics of aquatic environments in the natural habitats of zebrafish. Sci Rep 2023; 13:12028. [PMID: 37491571 PMCID: PMC10368656 DOI: 10.1038/s41598-023-36099-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 05/29/2023] [Indexed: 07/27/2023] Open
Abstract
Animal sensory systems are tightly adapted to the demands of their environment. In the visual domain, research has shown that many species have circuits and systems that exploit statistical regularities in natural visual signals. The zebrafish is a popular model animal in visual neuroscience, but relatively little quantitative data is available about the visual properties of the aquatic habitats where zebrafish reside, as compared to terrestrial environments. Improving our understanding of the visual demands of the aquatic habitats of zebrafish can enhance the insights about sensory neuroscience yielded by this model system. We analyzed a video dataset of zebrafish habitats captured by a stationary camera and compared this dataset to videos of terrestrial scenes in the same geographic area. Our analysis of the spatiotemporal structure in these videos suggests that zebrafish habitats are characterized by low visual contrast and strong motion when compared to terrestrial environments. Similar to terrestrial environments, zebrafish habitats tended to be dominated by dark contrasts, particularly in the lower visual field. We discuss how these properties of the visual environment can inform the study of zebrafish visual behavior and neural processing and, by extension, can inform our understanding of the vertebrate brain.
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Affiliation(s)
- Lanya T Cai
- Herbert Wertheim School of Optometry & Vision Science, University of California, Berkeley, CA, USA
| | - Venkatesh S Krishna
- Department of Biological Sciences, University of Toronto, Scarborough, ON, Canada
| | - Tim C Hladnik
- Werner Reichardt Centre for Integrative Neuroscience, Institute of Neurobiology, University of Tübingen, Tübingen, Germany
- Graduate Training Centre for Neuroscience, University of Tübingen, Tübingen, Germany
| | - Nicholas C Guilbeault
- Department of Biological Sciences, University of Toronto, Scarborough, ON, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Chinnian Vijayakumar
- Department of Zoology, Department of Zoology, St. Andrew's College, Gorakhpur, Uttar Pradesh, India
| | - Muthukumarasamy Arunachalam
- Department of Zoology, School of Biological Sciences, Central University of Kerala, Kasaragod, Kerala, India
- Centre for Inland Fishes and Conservation, St. Andrew's College, Gorakhpur, Uttar Pradesh, India
| | - Scott A Juntti
- Department of Biology, University of Maryland, College Park, MD, USA
| | - Aristides B Arrenberg
- Werner Reichardt Centre for Integrative Neuroscience, Institute of Neurobiology, University of Tübingen, Tübingen, Germany
| | - Tod R Thiele
- Department of Biological Sciences, University of Toronto, Scarborough, ON, Canada.
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada.
| | - Emily A Cooper
- Herbert Wertheim School of Optometry & Vision Science, University of California, Berkeley, CA, USA.
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA.
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10
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Lian Y, Williams S, Alexander AS, Hasselmo ME, Burkitt AN. Learning the Vector Coding of Egocentric Boundary Cells from Visual Data. J Neurosci 2023; 43:5180-5190. [PMID: 37286350 PMCID: PMC10342228 DOI: 10.1523/jneurosci.1071-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 05/25/2023] [Accepted: 05/27/2023] [Indexed: 06/09/2023] Open
Abstract
The use of spatial maps to navigate through the world requires a complex ongoing transformation of egocentric views of the environment into position within the allocentric map. Recent research has discovered neurons in retrosplenial cortex and other structures that could mediate the transformation from egocentric views to allocentric views. These egocentric boundary cells respond to the egocentric direction and distance of barriers relative to an animal's point of view. This egocentric coding based on the visual features of barriers would seem to require complex dynamics of cortical interactions. However, computational models presented here show that egocentric boundary cells can be generated with a remarkably simple synaptic learning rule that forms a sparse representation of visual input as an animal explores the environment. Simulation of this simple sparse synaptic modification generates a population of egocentric boundary cells with distributions of direction and distance coding that strikingly resemble those observed within the retrosplenial cortex. Furthermore, some egocentric boundary cells learnt by the model can still function in new environments without retraining. This provides a framework for understanding the properties of neuronal populations in the retrosplenial cortex that may be essential for interfacing egocentric sensory information with allocentric spatial maps of the world formed by neurons in downstream areas, including the grid cells in entorhinal cortex and place cells in the hippocampus.SIGNIFICANCE STATEMENT The computational model presented here demonstrates that the recently discovered egocentric boundary cells in retrosplenial cortex can be generated with a remarkably simple synaptic learning rule that forms a sparse representation of visual input as an animal explores the environment. Additionally, our model generates a population of egocentric boundary cells with distributions of direction and distance coding that strikingly resemble those observed within the retrosplenial cortex. This transformation between sensory input and egocentric representation in the navigational system could have implications for the way in which egocentric and allocentric representations interface in other brain areas.
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Affiliation(s)
- Yanbo Lian
- Department of Biomedical Engineering, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Simon Williams
- Department of Electrical and Electronic Engineering, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Andrew S Alexander
- Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts 02215
| | - Michael E Hasselmo
- Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts 02215
| | - Anthony N Burkitt
- Department of Biomedical Engineering, University of Melbourne, Melbourne, Victoria 3010, Australia
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11
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Wagner S, Strasser T. Impact of text contrast polarity on the retinal activity in myopes and emmetropes using modified pattern ERG. Sci Rep 2023; 13:11101. [PMID: 37423936 DOI: 10.1038/s41598-023-38192-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 07/05/2023] [Indexed: 07/11/2023] Open
Abstract
Environmental factors favoring myopia development are still being studied and there is accumulating evidence for a significant role of nearwork. Recently, reading standard black-on-white text was found to activate the retinal OFF pathway and induce choroidal thinning, which is associated with myopia onset. Contrarily, reading white-on-black text led to thicker choroids, being protective against myopia. Respective effects on retinal processing are yet unknown. Here, we exploratively assessed the impact of contrast polarity on the retinal activity and possible interactions with eccentricity and refractive error. We recorded pattern electroretinograms in myopic and emmetropic adults while presenting a dead leaves stimulus (DLS), overlaid by masks of different size in ring or circle shape, either filled with uniform gray or text of inverted or standard contrast. In myopes, retinal responses for DLS with standard and inverted contrast were larger when the perifovea was stimulated (6-12 deg), however, including the fovea resulted in smaller amplitudes for inverted contrast than in emmetropes. The retina of emmetropes was more sensitive to inverted contrast than to standard and gray within 12 deg, but most sensitive for gray in the perifovea. This demonstrates that the refractive error influences the sensitivity to text contrast polarity, with a special role of the peripheral retina, which is in line with previous studies about blur sensitivity. Defining whether the differences derive from retinal processing or anatomical features of a myopic eye requires further investigation. Our approach might be a first step to explain how nearwork promotes the eye's elongation.
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Affiliation(s)
- Sandra Wagner
- Institute for Ophthalmic Research, University of Tuebingen, Elfriede-Aulhorn-Str. 7, 72076, Tuebingen, Germany.
| | - Torsten Strasser
- Institute for Ophthalmic Research, University of Tuebingen, Elfriede-Aulhorn-Str. 7, 72076, Tuebingen, Germany
- University Eye Hospital Tuebingen, Elfriede-Aulhorn-Str. 7, 72076, Tuebingen, Germany
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12
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Breher K, Neumann A, Kurth D, Schaeffel F, Wahl S. ON and OFF receptive field processing in the presence of optical scattering. BIOMEDICAL OPTICS EXPRESS 2023; 14:2618-2628. [PMID: 37342711 PMCID: PMC10278613 DOI: 10.1364/boe.489117] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/14/2023] [Accepted: 04/14/2023] [Indexed: 06/23/2023]
Abstract
The balance of ON/OFF pathway activation in the retina plays a role in emmetropization. A new myopia control lens design uses contrast reduction to down-regulate a hypothesized enhanced ON contrast sensitivity in myopes. The study thus examined ON/OFF receptive field processing in myopes and non-myopes and the impact of contrast reduction. A psychophysical approach was used to measure the combined retinal-cortical output in the form of low-level ON and OFF contrast sensitivity with and without contrast reduction in 22 participants. ON responses were lower than OFF responses (ON 1.25 ± 0.03 vs. OFF 1.39 ± 0.03 log(CS); p < 0.0001) and myopes showed generally reduced sensitivities (myopes 1.25 ± 0.05 vs. non-myopes 1.39 ± 0.05 log(CS); p = 0.05). These findings remained unaffected by contrast reduction (p > 0.05). The study suggests that perceptual differences in ON and OFF signal processing between myopes and non-myopes exist but cannot explain how contrast reduction can inhibit myopia development.
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Affiliation(s)
- Katharina Breher
- Carl Zeiss Vision International GmbH, Turnstr. 27, 73430 Aalen, Germany
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany
| | - Antonia Neumann
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany
| | - Dominik Kurth
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany
| | - Frank Schaeffel
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany
- Institute of Molecular and Clinical Ophthalmology Basel, Mittlere Str. 91, 4056 Basel, Switzerland
| | - Siegfried Wahl
- Carl Zeiss Vision International GmbH, Turnstr. 27, 73430 Aalen, Germany
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany
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13
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Gupta D, Młynarski W, Sumser A, Symonova O, Svatoň J, Joesch M. Panoramic visual statistics shape retina-wide organization of receptive fields. Nat Neurosci 2023; 26:606-614. [PMID: 36959418 PMCID: PMC10076217 DOI: 10.1038/s41593-023-01280-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/14/2023] [Indexed: 03/25/2023]
Abstract
Statistics of natural scenes are not uniform-their structure varies dramatically from ground to sky. It remains unknown whether these nonuniformities are reflected in the large-scale organization of the early visual system and what benefits such adaptations would confer. Here, by relying on the efficient coding hypothesis, we predict that changes in the structure of receptive fields across visual space increase the efficiency of sensory coding. Using the mouse (Mus musculus) as a model species, we show that receptive fields of retinal ganglion cells change their shape along the dorsoventral retinal axis, with a marked surround asymmetry at the visual horizon, in agreement with our predictions. Our work demonstrates that, according to principles of efficient coding, the panoramic structure of natural scenes is exploited by the retina across space and cell types.
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Affiliation(s)
- Divyansh Gupta
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Wiktor Młynarski
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Anton Sumser
- Institute of Science and Technology Austria, Klosterneuburg, Austria
- Division of Neuroscience, Faculty of Biology, LMU, Munich, Germany
| | - Olga Symonova
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Jan Svatoň
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Maximilian Joesch
- Institute of Science and Technology Austria, Klosterneuburg, Austria.
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14
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St-Amand D, Baker CL. Model-Based Approach Shows ON Pathway Afferents Elicit a Transient Decrease of V1 Responses. J Neurosci 2023; 43:1920-1932. [PMID: 36759194 PMCID: PMC10027028 DOI: 10.1523/jneurosci.1220-22.2023] [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: 06/21/2022] [Revised: 01/29/2023] [Accepted: 01/30/2023] [Indexed: 02/11/2023] Open
Abstract
Neurons in the primary visual cortex (V1) receive excitation and inhibition from distinct parallel pathways processing lightness (ON) and darkness (OFF). V1 neurons overall respond more strongly to dark than light stimuli, consistent with a preponderance of darker regions in natural images, as well as human psychophysics. However, it has been unclear whether this "dark-dominance" is because of more excitation from the OFF pathway or more inhibition from the ON pathway. To understand the mechanisms behind dark-dominance, we record electrophysiological responses of individual simple-type V1 neurons to natural image stimuli and then train biologically inspired convolutional neural networks to predict the neurons' responses. Analyzing a sample of 71 neurons (in anesthetized, paralyzed cats of either sex) has revealed their responses to be more driven by dark than light stimuli, consistent with previous investigations. We show that this asymmetry is predominantly because of slower inhibition to dark stimuli rather than to stronger excitation from the thalamocortical OFF pathway. Consistent with dark-dominant neurons having faster responses than light-dominant neurons, we find dark-dominance to solely occur in the early latencies of neurons' responses. Neurons that are strongly dark-dominated also tend to be less orientation-selective. This novel approach gives us new insight into the dark-dominance phenomenon and provides an avenue to address new questions about excitatory and inhibitory integration in cortical neurons.SIGNIFICANCE STATEMENT Neurons in the early visual cortex respond on average more strongly to dark than to light stimuli, but the mechanisms behind this bias have been unclear. Here we address this issue by combining single-unit electrophysiology with a novel machine learning model to analyze neurons' responses to natural image stimuli in primary visual cortex. Using these techniques, we find slower inhibition to light than to dark stimuli to be the leading mechanism behind stronger dark responses. This slower inhibition to light might help explain other empirical findings, such as why orientation selectivity is weaker at earlier response latencies. These results demonstrate how imbalances in excitation versus inhibition can give rise to response asymmetries in cortical neuron responses.
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Affiliation(s)
- David St-Amand
- McGill Vision Research Unit, Department of Ophthalmology & Visual Sciences, McGill University, Montreal, Quebec H3G 1A4, Canada
| | - Curtis L Baker
- McGill Vision Research Unit, Department of Ophthalmology & Visual Sciences, McGill University, Montreal, Quebec H3G 1A4, Canada
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15
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Luminance Contrast Shifts Dominance Balance between ON and OFF Pathways in Human Vision. J Neurosci 2023; 43:993-1007. [PMID: 36535768 PMCID: PMC9908321 DOI: 10.1523/jneurosci.1672-22.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/14/2022] [Accepted: 12/10/2022] [Indexed: 12/23/2022] Open
Abstract
Human vision processes light and dark stimuli in visual scenes with separate ON and OFF neuronal pathways. In nature, stimuli lighter or darker than their local surround have different spatial properties and contrast distributions (Ratliff et al., 2010; Cooper and Norcia, 2015; Rahimi-Nasrabadi et al., 2021). Similarly, in human vision, we show that luminance contrast affects the perception of lights and darks differently. At high contrast, human subjects of both sexes locate dark stimuli faster and more accurately than light stimuli, which is consistent with a visual system dominated by the OFF pathway. However, at low contrast, they locate light stimuli faster and more accurately than dark stimuli, which is consistent with a visual system dominated by the ON pathway. Luminance contrast was strongly correlated with multiple ON/OFF dominance ratios estimated from light/dark ratios of performance errors, missed targets, or reaction times (RTs). All correlations could be demonstrated at multiple eccentricities of the central visual field with an ON-OFF perimetry test implemented in a head-mounted visual display. We conclude that high-contrast stimuli are processed faster and more accurately by OFF pathways than ON pathways. However, the OFF dominance shifts toward ON dominance when stimulus contrast decreases, as expected from the higher-contrast sensitivity of ON cortical pathways (Kremkow et al., 2014; Rahimi-Nasrabadi et al., 2021). The results highlight the importance of contrast polarity in visual field measurements and predict a loss of low-contrast vision in humans with ON pathway deficits, as demonstrated in animal models (Sarnaik et al., 2014).SIGNIFICANCE STATEMENT ON and OFF retino-thalamo-cortical pathways respond differently to luminance contrast. In both animal models and humans, low contrasts drive stronger responses from ON pathways, whereas high contrasts drive stronger responses from OFF pathways. We demonstrate that these ON-OFF pathway differences have a correlate in human vision. At low contrast, humans locate light targets faster and more accurately than dark targets but, as contrast increases, dark targets become more visible than light targets. We also demonstrate that contrast is strongly correlated with multiple light/dark ratios of visual performance in central vision. These results provide a link between neuronal physiology and human vision while emphasizing the importance of stimulus polarity in measurements of visual fields and contrast sensitivity.
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16
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Tesileanu T, Piasini E, Balasubramanian V. Efficient processing of natural scenes in visual cortex. Front Cell Neurosci 2022; 16:1006703. [PMID: 36545653 PMCID: PMC9760692 DOI: 10.3389/fncel.2022.1006703] [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: 07/29/2022] [Accepted: 11/17/2022] [Indexed: 12/12/2022] Open
Abstract
Neural circuits in the periphery of the visual, auditory, and olfactory systems are believed to use limited resources efficiently to represent sensory information by adapting to the statistical structure of the natural environment. This "efficient coding" principle has been used to explain many aspects of early visual circuits including the distribution of photoreceptors, the mosaic geometry and center-surround structure of retinal receptive fields, the excess OFF pathways relative to ON pathways, saccade statistics, and the structure of simple cell receptive fields in V1. We know less about the extent to which such adaptations may occur in deeper areas of cortex beyond V1. We thus review recent developments showing that the perception of visual textures, which depends on processing in V2 and beyond in mammals, is adapted in rats and humans to the multi-point statistics of luminance in natural scenes. These results suggest that central circuits in the visual brain are adapted for seeing key aspects of natural scenes. We conclude by discussing how adaptation to natural temporal statistics may aid in learning and representing visual objects, and propose two challenges for the future: (1) explaining the distribution of shape sensitivity in the ventral visual stream from the statistics of object shape in natural images, and (2) explaining cell types of the vertebrate retina in terms of feature detectors that are adapted to the spatio-temporal structures of natural stimuli. We also discuss how new methods based on machine learning may complement the normative, principles-based approach to theoretical neuroscience.
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Affiliation(s)
- Tiberiu Tesileanu
- Center for Computational Neuroscience, Flatiron Institute, New York, NY, United States,*Correspondence: Tiberiu Tesileanu
| | - Eugenio Piasini
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy,Eugenio Piasini
| | - Vijay Balasubramanian
- Department of Physics and Astronomy, David Rittenhouse Laboratory, University of Pennsylvania, Philadelphia, PA, United States,Santa Fe Institute, Santa Fe, NM, United States
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17
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Freedland J, Rieke F. Systematic reduction of the dimensionality of natural scenes allows accurate predictions of retinal ganglion cell spike outputs. Proc Natl Acad Sci U S A 2022; 119:e2121744119. [PMID: 36343230 PMCID: PMC9674269 DOI: 10.1073/pnas.2121744119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 09/23/2022] [Indexed: 11/09/2022] Open
Abstract
The mammalian retina engages a broad array of linear and nonlinear circuit mechanisms to convert natural scenes into retinal ganglion cell (RGC) spike outputs. Although many individual integration mechanisms are well understood, we know less about how multiple mechanisms interact to encode the complex spatial features present in natural inputs. Here, we identified key spatial features in natural scenes that shape encoding by primate parasol RGCs. Our approach identified simplifications in the spatial structure of natural scenes that minimally altered RGC spike responses. We observed that reducing natural movies into 16 linearly integrated regions described ∼80% of the structure of parasol RGC spike responses; this performance depended on the number of regions but not their precise spatial locations. We used simplified stimuli to design high-dimensional metamers that recapitulated responses to naturalistic movies. Finally, we modeled the retinal computations that convert flashed natural images into one-dimensional spike counts.
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Affiliation(s)
- Julian Freedland
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA 98195
| | - Fred Rieke
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195
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18
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Almasi A, Sun SH, Yunzab M, Jung YJ, Meffin H, Ibbotson MR. How Stimulus Statistics Affect the Receptive Fields of Cells in Primary Visual Cortex. J Neurosci 2022; 42:5198-5211. [PMID: 35610048 PMCID: PMC9236288 DOI: 10.1523/jneurosci.0664-21.2022] [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: 03/29/2021] [Revised: 05/08/2022] [Accepted: 05/11/2022] [Indexed: 12/31/2022] Open
Abstract
We studied the changes that neuronal receptive field (RF) models undergo when the statistics of the stimulus are changed from those of white Gaussian noise (WGN) to those of natural scenes (NSs), by fitting the models to multielectrode data recorded from primary visual cortex (V1) of female cats. This allowed the estimation of both a cascade of linear filters on the stimulus, as well as the static nonlinearities that map the output of the filters to the neuronal spike rates. We found that cells respond differently to these two classes of stimuli, with mostly higher spike rates and shorter response latencies to NSs than to WGN. The most striking finding was that NSs resulted in RFs that had additional uncovered filters compared with WGN. This finding was not an artifact of the higher spike rates observed for NSs relative to WGN, but rather was related to a change in coding. Our results reveal a greater extent of nonlinear processing in V1 neurons when stimulated using NSs compared with WGN. Our findings indicate the existence of nonlinear mechanisms that endow V1 neurons with context-dependent transmission of visual information.SIGNIFICANCE STATEMENT This study addresses a fundamental question about the concept of the receptive field (RF): does the encoding of information depend on the context or statistical regularities of the stimulus type? We applied state-of-the-art RF modeling techniques to data collected from multielectrode recordings from cat visual cortex in response to two statistically distinct stimulus types: white Gaussian noise and natural scenes. We find significant differences between the RFs that emerge from our data-driven modeling. Natural scenes result in far more complex RFs that combine multiple features in the visual input. Our findings reveal that different regimes or modes of operation are at work in visual cortical processing depending on the information present in the visual input. The complexity of V1 neural coding appears to be dependent on the complexity of the stimulus. We believe this new finding will have interesting implications for our understanding of the efficient transmission of information in sensory systems, which is an integral assumption of many computational theories (e.g., efficient and predictive coding of sensory processing in the brain).
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Affiliation(s)
- Ali Almasi
- National Vision Research Institute, Carlton, Victoria 3053, Australia
| | - Shi Hai Sun
- National Vision Research Institute, Carlton, Victoria 3053, Australia
| | - Molis Yunzab
- National Vision Research Institute, Carlton, Victoria 3053, Australia
| | - Young Jun Jung
- National Vision Research Institute, Carlton, Victoria 3053, Australia
| | - Hamish Meffin
- Department of Biomedical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michael R Ibbotson
- National Vision Research Institute, Carlton, Victoria 3053, Australia
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
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19
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Abstract
An ultimate goal in retina science is to understand how the neural circuit of the retina processes natural visual scenes. Yet most studies in laboratories have long been performed with simple, artificial visual stimuli such as full-field illumination, spots of light, or gratings. The underlying assumption is that the features of the retina thus identified carry over to the more complex scenario of natural scenes. As the application of corresponding natural settings is becoming more commonplace in experimental investigations, this assumption is being put to the test and opportunities arise to discover processing features that are triggered by specific aspects of natural scenes. Here, we review how natural stimuli have been used to probe, refine, and complement knowledge accumulated under simplified stimuli, and we discuss challenges and opportunities along the way toward a comprehensive understanding of the encoding of natural scenes. Expected final online publication date for the Annual Review of Vision Science, Volume 8 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Dimokratis Karamanlis
- Department of Ophthalmology, University Medical Center Göttingen, Göttingen, Germany.,Bernstein Center for Computational Neuroscience Göttingen, Göttingen, Germany.,International Max Planck Research School for Neurosciences, Göttingen, Germany
| | - Helene Marianne Schreyer
- Department of Ophthalmology, University Medical Center Göttingen, Göttingen, Germany.,Bernstein Center for Computational Neuroscience Göttingen, Göttingen, Germany
| | - Tim Gollisch
- Department of Ophthalmology, University Medical Center Göttingen, Göttingen, Germany.,Bernstein Center for Computational Neuroscience Göttingen, Göttingen, Germany.,Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany
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20
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Gajjar S, Ostrin LA. A systematic review of near work and myopia: measurement, relationships, mechanisms and clinical corollaries. Acta Ophthalmol 2022; 100:376-387. [PMID: 34622560 DOI: 10.1111/aos.15043] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 09/02/2021] [Accepted: 09/22/2021] [Indexed: 12/17/2022]
Abstract
After decades of investigation, the role of near work in myopia remains unresolved, with some studies reporting no relationship and others finding the opposite. This systematic review is intended to summarize classic and recent literature investigating near work and the onset and progression of myopia, potential mechanisms and pertinent clinical recommendations. The impact of electronic device use is considered. PubMed and Medline were used to find peer-reviewed cross-sectional and longitudinal studies related to near work and myopia from 1980 to July 2020 using the PRISMA checklist. Studies were chosen using the Joanna Briggs Institute checklist, with a focus on studies with a sample size greater than 50. Studies were independently evaluated; conclusions were drawn per these evaluations. Numerous cross-sectional studies found increased odds ratio of myopia with increased near work. While early longitudinal studies failed to find this relationship, more recent longitudinal studies have found a relationship between myopia and near work. Rather than daily duration of near work, interest has increased regarding absolute working distance and duration of continuous near viewing. Several reports have found that shorter working distances (<30 cm) and continuous near-work activity (>30 min) are risk factors for myopia onset and progression. Novel objective continuously measuring rangefinding devices have been developed to better address these questions. The literature is conflicting, likely due to the subjective and variable nature in which near work has been quantified and a paucity of longitudinal studies. We conclude that more precise objective measures of near viewing behaviour are necessary to make definitive conclusions regarding the relationship between myopia and near work. Focus should shift to utilizing objective and continuously measuring instruments to quantify near-work behaviours in children, followed longitudinally, to understand the complex factors related to near work. A better understanding of the roles of absolute working distance, temporal properties, viewing breaks and electronic device use on myopia development and progression will aid in the development of evidence-based clinical recommendations for behavioural modifications to prevent and slow myopia.
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Affiliation(s)
- Shail Gajjar
- University of Houston College of Optometry Houston TX USA
| | - Lisa A. Ostrin
- University of Houston College of Optometry Houston TX USA
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21
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Skyberg R, Tanabe S, Chen H, Cang J. Coarse-to-fine processing drives the efficient coding of natural scenes in mouse visual cortex. Cell Rep 2022; 38:110606. [PMID: 35354030 PMCID: PMC9189856 DOI: 10.1016/j.celrep.2022.110606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 01/07/2022] [Accepted: 03/10/2022] [Indexed: 12/01/2022] Open
Abstract
The visual system processes sensory inputs sequentially, perceiving coarse information before fine details. Here we study the neural basis of coarse-to-fine processing and its computational benefits in natural vision. We find that primary visual cortical neurons in awake mice respond to natural scenes in a coarse-to-fine manner, primarily driven by individual neurons rapidly shifting their spatial frequency preference from low to high over a brief response period. This shift transforms the population response in a way that counteracts the statistical regularities of natural scenes, thereby reducing redundancy and generating a more efficient neural representation. The increase in representational efficiency does not occur in either dark-reared or anesthetized mice, which show significantly attenuated coarse-to-fine spatial processing. Collectively, these results illustrate that coarse-to-fine processing is state dependent, develops postnatally via visual experience, and provides a computational advantage by generating more efficient representations of the complex spatial statistics of ethologically relevant natural scenes. Skyberg et al. show that the visual cortex of mice processes natural scenes in a coarse-to-fine manner, driven by individual neuron’s temporal dynamics. These response dynamics, which require visual experience to develop, reduce redundancy in the neural code and lead to more efficient representations of complex visual stimuli.
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Affiliation(s)
- Rolf Skyberg
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, VA 22904, USA
| | - Seiji Tanabe
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, VA 22904, USA
| | - Hui Chen
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, VA 22904, USA
| | - Jianhua Cang
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, VA 22904, USA.
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22
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Hathibelagal AR, Prajapati V, Jayagopi I, Jalali S, Ganeshrao SB. Age-related decline in function of ON and OFF visual pathways. PLoS One 2022; 17:e0261489. [PMID: 35316274 PMCID: PMC8939797 DOI: 10.1371/journal.pone.0261489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/08/2022] [Indexed: 11/18/2022] Open
Abstract
Purpose A simple psychophysical paradigm is available as a digital application in iOS devices such as iPad to measure the function of ON and OFF visual pathways. However, an age-matched normative database is not readily available. The purpose of the study is to evaluate the response of ON and OFF visual pathways as a function of age. Methods 158 normal healthy adults (84 males and 74 females) whose age ranged 18–80 years participated in the study. None of them had any ocular disease (except cataract of grade II or less) and visual acuity of ≤ 20/25. Monocular testing (only one eye) was performed on the ‘EyeSpeed’ application on an iPad at 40cm distance. The targets ranged between 1 to 3 light or dark squares presented randomly in a noise background and participants responded by indicating the number of squares by touching the screen as fast as possible. The main outcome variables are reaction time, accuracy and performance index (1 / speed * accuracy). Results The median reaction time was shorter (Median (IQR): 1.53s (0.49) [dark] Vs 1.76s (0.58) [light], p < 0.001) and accuracy was higher (97.21% (3.30) [dark] Vs 95.15% (5.10) [light], p < 0.001) for dark targets than the light targets. Performance index and reaction time for both target types significantly correlated with age (ρ = -0.41 to -0.43; p < 0.001). Conclusions This normative database will be useful to quantify disease-specific defects. More importantly, the ON pathway function can potentially serve as a surrogate for rod photoreceptor function.
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Affiliation(s)
- Amithavikram R. Hathibelagal
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India
- Prof. Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
- * E-mail:
| | - Vishal Prajapati
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India
- Prof. Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
| | - Indrani Jayagopi
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India
- Prof. Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
| | - Subhadra Jalali
- Srimati Kanuri Santhamma Centre for vitreoretinal diseases, L V Prasad Eye Institute, Hyderabad, India
- Jasti V Ramanamma Children’s Eye Care Centre, L V Prasad Eye Institute, Hyderabad, India
| | - Shonraj Ballae Ganeshrao
- Department of Optometry, Manipal College of Health Professions, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
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23
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Yu Z, Turner MH, Baudin J, Rieke F. Adaptation in cone photoreceptors contributes to an unexpected insensitivity of primate On parasol retinal ganglion cells to spatial structure in natural images. eLife 2022; 11:e70611. [PMID: 35285798 PMCID: PMC8956286 DOI: 10.7554/elife.70611] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 03/13/2022] [Indexed: 02/06/2023] Open
Abstract
Neural circuits are constructed from nonlinear building blocks, and not surprisingly overall circuit behavior is often strongly nonlinear. But neural circuits can also behave near linearly, and some circuits shift from linear to nonlinear behavior depending on stimulus conditions. Such control of nonlinear circuit behavior is fundamental to neural computation. Here, we study a surprising stimulus dependence of the responses of macaque On (but not Off) parasol retinal ganglion cells: these cells respond nonlinearly to spatial structure in some stimuli but near linearly to spatial structure in others, including natural inputs. We show that these differences in the linearity of the integration of spatial inputs can be explained by a shift in the balance of excitatory and inhibitory synaptic inputs that originates at least partially from adaptation in the cone photoreceptors. More generally, this highlights how subtle asymmetries in signaling - here in the cone signals - can qualitatively alter circuit computation.
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Affiliation(s)
- Zhou Yu
- Department of Physiology and Biophysics, University of WashingtonSeattleUnited States
| | - Maxwell H Turner
- Department of Physiology and Biophysics, University of WashingtonSeattleUnited States
| | - Jacob Baudin
- Department of Physiology and Biophysics, University of WashingtonSeattleUnited States
| | - Fred Rieke
- Department of Physiology and Biophysics, University of WashingtonSeattleUnited States
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24
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Ketkar MD, Gür B, Molina-Obando S, Ioannidou M, Martelli C, Silies M. First-order visual interneurons distribute distinct contrast and luminance information across ON and OFF pathways to achieve stable behavior. eLife 2022; 11:74937. [PMID: 35263247 PMCID: PMC8967382 DOI: 10.7554/elife.74937] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 03/03/2022] [Indexed: 11/26/2022] Open
Abstract
The accurate processing of contrast is the basis for all visually guided behaviors. Visual scenes with rapidly changing illumination challenge contrast computation because photoreceptor adaptation is not fast enough to compensate for such changes. Yet, human perception of contrast is stable even when the visual environment is quickly changing, suggesting rapid post receptor luminance gain control. Similarly, in the fruit fly Drosophila, such gain control leads to luminance invariant behavior for moving OFF stimuli. Here, we show that behavioral responses to moving ON stimuli also utilize a luminance gain, and that ON-motion guided behavior depends on inputs from three first-order interneurons L1, L2, and L3. Each of these neurons encodes contrast and luminance differently and distributes information asymmetrically across both ON and OFF contrast-selective pathways. Behavioral responses to both ON and OFF stimuli rely on a luminance-based correction provided by L1 and L3, wherein L1 supports contrast computation linearly, and L3 non-linearly amplifies dim stimuli. Therefore, L1, L2, and L3 are not specific inputs to ON and OFF pathways but the lamina serves as a separate processing layer that distributes distinct luminance and contrast information across ON and OFF pathways to support behavior in varying conditions.
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Affiliation(s)
- Madhura D Ketkar
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Burak Gür
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Sebastian Molina-Obando
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Maria Ioannidou
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Carlotta Martelli
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Marion Silies
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University of Mainz, Mainz, Germany
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25
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Caramellino R, Piasini E, Buccellato A, Carboncino A, Balasubramanian V, Zoccolan D. Rat sensitivity to multipoint statistics is predicted by efficient coding of natural scenes. eLife 2021; 10:e72081. [PMID: 34872633 PMCID: PMC8651284 DOI: 10.7554/elife.72081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 11/18/2021] [Indexed: 01/23/2023] Open
Abstract
Efficient processing of sensory data requires adapting the neuronal encoding strategy to the statistics of natural stimuli. Previously, in Hermundstad et al., 2014, we showed that local multipoint correlation patterns that are most variable in natural images are also the most perceptually salient for human observers, in a way that is compatible with the efficient coding principle. Understanding the neuronal mechanisms underlying such adaptation to image statistics will require performing invasive experiments that are impossible in humans. Therefore, it is important to understand whether a similar phenomenon can be detected in animal species that allow for powerful experimental manipulations, such as rodents. Here we selected four image statistics (from single- to four-point correlations) and trained four groups of rats to discriminate between white noise patterns and binary textures containing variable intensity levels of one of such statistics. We interpreted the resulting psychometric data with an ideal observer model, finding a sharp decrease in sensitivity from two- to four-point correlations and a further decrease from four- to three-point. This ranking fully reproduces the trend we previously observed in humans, thus extending a direct demonstration of efficient coding to a species where neuronal and developmental processes can be interrogated and causally manipulated.
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Affiliation(s)
| | - Eugenio Piasini
- Computational Neuroscience Initiative, University of PennsylvaniaPhiladelphiaUnited States
| | - Andrea Buccellato
- Visual Neuroscience Lab, International School for Advanced StudiesTriesteItaly
| | - Anna Carboncino
- Visual Neuroscience Lab, International School for Advanced StudiesTriesteItaly
| | - Vijay Balasubramanian
- Computational Neuroscience Initiative, University of PennsylvaniaPhiladelphiaUnited States
| | - Davide Zoccolan
- Visual Neuroscience Lab, International School for Advanced StudiesTriesteItaly
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Liu X, Li H, Wang Y, Lei T, Wang J, Spillmann L, Andolina IM, Wang W. From Receptive to Perceptive Fields: Size-Dependent Asymmetries in Both Negative Afterimages and Subcortical On and Off Post-Stimulus Responses. J Neurosci 2021; 41:7813-7830. [PMID: 34326144 PMCID: PMC8445057 DOI: 10.1523/jneurosci.0300-21.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 07/11/2021] [Accepted: 07/13/2021] [Indexed: 11/21/2022] Open
Abstract
Negative afterimages are perceptual phenomena that occur after physical stimuli disappear from sight. Their origin is linked to transient post-stimulus responses of visual neurons. The receptive fields (RFs) of these subcortical ON- and OFF-center neurons exhibit antagonistic interactions between central and surrounding visual space, resulting in selectivity for stimulus polarity and size. These two features are closely intertwined, yet their relationship to negative afterimage perception remains unknown. Here we tested whether size differentially affects the perception of bright and dark negative afterimages in humans of both sexes, and how this correlates with neural mechanisms in subcortical ON and OFF cells. Psychophysically, we found a size-dependent asymmetry whereby dark disks produce stronger and longer-lasting negative afterimages than bright disks of equal contrast at sizes >0.8°. Neurophysiological recordings from retinal and relay cells in female cat dorsal lateral geniculate nucleus showed that subcortical ON cells exhibited stronger sustained post-stimulus responses to dark disks, than OFF cells to bright disks, at sizes >1°. These sizes agree with the emergence of center-surround antagonism, revealing stronger suppression to opposite-polarity stimuli for OFF versus ON cells, particularly in dorsal lateral geniculate nucleus. Using a network-based retino-geniculate model, we confirmed stronger antagonism and temporal transience for OFF-cell post-stimulus rebound responses. A V1 population model demonstrated that both strength and duration asymmetries can be propagated to downstream cortical areas. Our results demonstrate how size-dependent antagonism impacts both the neuronal post-stimulus response and the resulting afterimage percepts, thereby supporting the idea of perceptual RFs reflecting the underlying neuronal RF organization of single cells.SIGNIFICANCE STATEMENT Visual illusions occur when sensory inputs and perceptual outcomes do not match, and provide a valuable tool to understand transformations from neural to perceptual responses. A classic example are negative afterimages that remain visible after a stimulus is removed from view. Such perceptions are linked to responses in early visual neurons, yet the details remain poorly understood. Combining human psychophysics, neurophysiological recordings in cats and retino-thalamo-cortical computational modeling, our study reveals how stimulus size and the receptive-field structure of subcortical ON and OFF cells contributes to the parallel asymmetries between neural and perceptual responses to bright versus dark afterimages. Thus, this work provides a deeper link from the underlying neural mechanisms to the resultant perceptual outcomes.
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Affiliation(s)
- Xu Liu
- Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hui Li
- Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Ye Wang
- State Key Laboratory of Media Convergence and Communication, Neuroscience and Intelligent Media Institute, Communication University of China, Beijing, 100024, China
| | - Tianhao Lei
- Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jijun Wang
- Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Psychotic Disorders, Shanghai, 200030, China
| | - Lothar Spillmann
- Department of Neurology, University of Freiburg, Freiburg, 79085, Germany
| | - Ian Max Andolina
- Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, 200031, China
- Shanghai Center for Brain and Brain-inspired Intelligence Technology, Shanghai, 200031, China
| | - Wei Wang
- Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, 200031, China
- Shanghai Center for Brain and Brain-inspired Intelligence Technology, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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27
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The temporal integration windows for visual mirror symmetry. Vision Res 2021; 188:184-192. [PMID: 34352477 DOI: 10.1016/j.visres.2021.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 04/27/2021] [Accepted: 07/19/2021] [Indexed: 11/18/2022]
Abstract
Symmetry perception in dot patterns is tolerant to temporal delays of up to 60 ms within and between element pairs. However, it is not known how factors effecting symmetry discrimination in static patterns might affect temporal integration in dynamic patterns. One such feature is luminance polarity. Using dynamic stimuli with increasing temporal delay (SOA) between the onset of the first and second element in a symmetric pair, we investigated how four different luminance-polarity conditions affected the temporal integration of symmetric patterns. All four luminance polarity conditions showed similar upper temporal limits of approximately 60 ms. However psychophysical performance over all delay durations showed significantly higher symmetry thresholds for unmatched-polarity patterns at short delays, but also significantly less sensitivity to increasing temporal delay relative to matched-polarity patterns. These varying temporal windows are consistent with the involvement of a fast, sensitive first-order mechanism for matched-polarity patterns, and a slower, more robust second-order mechanism for unmatched-polarity patterns. Temporal integration windows for unmatched-polarity patterns were not consistent with performance expected from attentional mechanisms alone, and instead supports the involvement of second-order mechanisms that combines information from ON and OFF channels.
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28
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Archer DR, Alitto HJ, Usrey WM. Stimulus Contrast Affects Spatial Integration in the Lateral Geniculate Nucleus of Macaque Monkeys. J Neurosci 2021; 41:6246-6256. [PMID: 34103362 PMCID: PMC8287990 DOI: 10.1523/jneurosci.2946-20.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 05/30/2021] [Accepted: 06/02/2021] [Indexed: 11/21/2022] Open
Abstract
Gain-control mechanisms adjust neuronal responses to accommodate the wide range of stimulus conditions in the natural environment. Contrast gain control and extraclassical surround suppression are two manifestations of gain control that govern the responses of neurons in the early visual system. Understanding how these two forms of gain control interact has important implications for the detection and discrimination of stimuli across a range of contrast conditions. Here, we report that stimulus contrast affects spatial integration in the lateral geniculate nucleus of alert macaque monkeys (male and female), whereby neurons exhibit a reduction in the strength of extraclassical surround suppression and an expansion in the preferred stimulus size with low-contrast stimuli compared with high-contrast stimuli. Effects were greater for magnocellular neurons than for parvocellular neurons, indicating stream-specific interactions between stimulus contrast and stimulus size. Within the magnocellular pathway, contrast-dependent effects were comparable for ON-center and OFF-center neurons, despite ON neurons having larger receptive fields, less pronounced surround suppression, and more pronounced contrast gain control than OFF neurons. Together, these findings suggest that the parallel streams delivering visual information from retina to primary visual cortex, serve not only to broaden the range of signals delivered to cortex, but also to provide a substrate for differential interactions between stimulus contrast and stimulus size that may serve to improve stimulus detection and stimulus discrimination under pathway-specific lower and higher contrast conditions, respectively.SIGNIFICANCE STATEMENT Stimulus contrast is a salient feature of visual scenes. Here we examine the influence of stimulus contrast on spatial integration in the lateral geniculate nucleus (LGN). Our results demonstrate that increases in contrast generally increase extraclassical suppression and decrease the size of optimal stimuli, indicating a reduction in the extent of visual space from which LGN neurons integrate signals. Differences between magnocellular and parvocellular neurons are noteworthy and further demonstrate that the feedforward parallel pathways to cortex increase the range of information conveyed for downstream cortical processing, a range broadened by diversity in the ON and OFF pathways. These results have important implications for more complex visual processing that underly the detection and discrimination of stimuli under varying natural conditions.
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Affiliation(s)
- Darlene R Archer
- Center for Neuroscience, University of California, Davis, Davis, California 95616
- SUNY College of Optometry, New York, New York 10036
- Center for Neural Science, New York University, New York, New York 10003
| | - Henry J Alitto
- Center for Neuroscience, University of California, Davis, Davis, California 95616
| | - W Martin Usrey
- Center for Neuroscience, University of California, Davis, Davis, California 95616
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29
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Qiu Y, Zhao Z, Klindt D, Kautzky M, Szatko KP, Schaeffel F, Rifai K, Franke K, Busse L, Euler T. Natural environment statistics in the upper and lower visual field are reflected in mouse retinal specializations. Curr Biol 2021; 31:3233-3247.e6. [PMID: 34107304 DOI: 10.1016/j.cub.2021.05.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 04/06/2021] [Accepted: 05/11/2021] [Indexed: 12/29/2022]
Abstract
Pressures for survival make sensory circuits adapted to a species' natural habitat and its behavioral challenges. Thus, to advance our understanding of the visual system, it is essential to consider an animal's specific visual environment by capturing natural scenes, characterizing their statistical regularities, and using them to probe visual computations. Mice, a prominent visual system model, have salient visual specializations, being dichromatic with enhanced sensitivity to green and UV in the dorsal and ventral retina, respectively. However, the characteristics of their visual environment that likely have driven these adaptations are rarely considered. Here, we built a UV-green-sensitive camera to record footage from mouse habitats. This footage is publicly available as a resource for mouse vision research. We found chromatic contrast to greatly diverge in the upper, but not the lower, visual field. Moreover, training a convolutional autoencoder on upper, but not lower, visual field scenes was sufficient for the emergence of color-opponent filters, suggesting that this environmental difference might have driven superior chromatic opponency in the ventral mouse retina, supporting color discrimination in the upper visual field. Furthermore, the upper visual field was biased toward dark UV contrasts, paralleled by more light-offset-sensitive ganglion cells in the ventral retina. Finally, footage recorded at twilight suggests that UV promotes aerial predator detection. Our findings support that natural scene statistics shaped early visual processing in evolution.
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Affiliation(s)
- Yongrong Qiu
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience (GTC), International Max Planck Research School, University of Tübingen, 72076 Tübingen, Germany
| | - Zhijian Zhao
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany
| | - David Klindt
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience (GTC), International Max Planck Research School, University of Tübingen, 72076 Tübingen, Germany
| | - Magdalena Kautzky
- Division of Neurobiology, Faculty of Biology, LMU Munich, 82152 Planegg-Martinsried, Germany; Graduate School of Systemic Neurosciences (GSN), LMU Munich, 82152 Planegg-Martinsried, Germany
| | - Klaudia P Szatko
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience (GTC), International Max Planck Research School, University of Tübingen, 72076 Tübingen, Germany; Bernstein Centre for Computational Neuroscience, 72076 Tübingen, Germany
| | - Frank Schaeffel
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany
| | - Katharina Rifai
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Carl Zeiss Vision International GmbH, 73430 Aalen, Germany
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; Bernstein Centre for Computational Neuroscience, 72076 Tübingen, Germany
| | - Laura Busse
- Division of Neurobiology, Faculty of Biology, LMU Munich, 82152 Planegg-Martinsried, Germany; Bernstein Centre for Computational Neuroscience, 82152 Planegg-Martinsried, Germany.
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; Bernstein Centre for Computational Neuroscience, 72076 Tübingen, Germany.
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30
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Hsu WMM, Kastner DB, Baccus SA, Sharpee TO. How inhibitory neurons increase information transmission under threshold modulation. Cell Rep 2021; 35:109158. [PMID: 34038717 PMCID: PMC8846953 DOI: 10.1016/j.celrep.2021.109158] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 02/14/2021] [Accepted: 04/29/2021] [Indexed: 11/28/2022] Open
Abstract
Modulation of neuronal thresholds is ubiquitous in the brain. Phenomena such as figure-ground segmentation, motion detection, stimulus anticipation, and shifts in attention all involve changes in a neuron’s threshold based on signals from larger scales than its primary inputs. However, this modulation reduces the accuracy with which neurons can represent their primary inputs, creating a mystery as to why threshold modulation is so widespread in the brain. We find that modulation is less detrimental than other forms of neuronal variability and that its negative effects can be nearly completely eliminated if modulation is applied selectively to sparsely responding neurons in a circuit by inhibitory neurons. We verify these predictions in the retina where we find that inhibitory amacrine cells selectively deliver modulation signals to sparsely responding ganglion cell types. Our findings elucidate the central role that inhibitory neurons play in maximizing information transmission under modulation. Modulation of neuronal thresholds is ubiquitous in the brain but reduces the accuracy of neural signaling. Hsu et al. show that the negative impact of threshold modulation can be almost completely eliminated when modulation is not delivered uniformly to all neurons but only to a subset and via inhibitory neurons.
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Affiliation(s)
- Wei-Mien M Hsu
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA; Department of Physics, University of California, San Diego, La Jolla, CA, USA
| | - David B Kastner
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, School of Medicine, San Francisco, CA, USA; Department of Neurobiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Stephen A Baccus
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Tatyana O Sharpee
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA; Department of Physics, University of California, San Diego, La Jolla, CA, USA.
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31
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Röth K, Shao S, Gjorgjieva J. Efficient population coding depends on stimulus convergence and source of noise. PLoS Comput Biol 2021; 17:e1008897. [PMID: 33901195 PMCID: PMC8075262 DOI: 10.1371/journal.pcbi.1008897] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 03/19/2021] [Indexed: 11/30/2022] Open
Abstract
Sensory organs transmit information to downstream brain circuits using a neural code comprised of spikes from multiple neurons. According to the prominent efficient coding framework, the properties of sensory populations have evolved to encode maximum information about stimuli given biophysical constraints. How information coding depends on the way sensory signals from multiple channels converge downstream is still unknown, especially in the presence of noise which corrupts the signal at different points along the pathway. Here, we calculated the optimal information transfer of a population of nonlinear neurons under two scenarios. First, a lumped-coding channel where the information from different inputs converges to a single channel, thus reducing the number of neurons. Second, an independent-coding channel when different inputs contribute independent information without convergence. In each case, we investigated information loss when the sensory signal was corrupted by two sources of noise. We determined critical noise levels at which the optimal number of distinct thresholds of individual neurons in the population changes. Comparing our system to classical physical systems, these changes correspond to first- or second-order phase transitions for the lumped- or the independent-coding channel, respectively. We relate our theoretical predictions to coding in a population of auditory nerve fibers recorded experimentally, and find signatures of efficient coding. Our results yield important insights into the diverse coding strategies used by neural populations to optimally integrate sensory stimuli in the presence of distinct sources of noise.
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Affiliation(s)
- Kai Röth
- Computation in Neural Circuits Group, Max Planck Institute for Brain Research, Frankfurt, Germany
- School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Shuai Shao
- Computation in Neural Circuits Group, Max Planck Institute for Brain Research, Frankfurt, Germany
- Donders Institute and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Julijana Gjorgjieva
- Computation in Neural Circuits Group, Max Planck Institute for Brain Research, Frankfurt, Germany
- School of Life Sciences, Technical University of Munich, Freising, Germany
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32
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Statistical analysis and optimality of neural systems. Neuron 2021; 109:1227-1241.e5. [DOI: 10.1016/j.neuron.2021.01.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 09/10/2020] [Accepted: 01/19/2021] [Indexed: 11/19/2022]
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33
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Song Z, Zhou Y, Feng J, Juusola M. Multiscale 'whole-cell' models to study neural information processing - New insights from fly photoreceptor studies. J Neurosci Methods 2021; 357:109156. [PMID: 33775669 DOI: 10.1016/j.jneumeth.2021.109156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 03/21/2021] [Accepted: 03/23/2021] [Indexed: 11/26/2022]
Abstract
Understanding a neuron's input-output relationship is a longstanding challenge. Arguably, these signalling dynamics can be better understood if studied at three levels of analysis: computational, algorithmic and implementational (Marr, 1982). But it is difficult to integrate such analyses into a single platform that can realistically simulate neural information processing. Multiscale dynamical "whole-cell" modelling, a recent systems biology approach, makes this possible. Dynamical "whole-cell" models are computational models that aim to account for the integrated function of numerous genes or molecules to behave like virtual cells in silico. However, because constructing such models is laborious, only a couple of examples have emerged since the first one, built for Mycoplasma genitalium bacterium, was reported in 2012. Here, we review dynamic "whole-cell" neuron models for fly photoreceptors and how these have been used to study neural information processing. Specifically, we review how the models have helped uncover the mechanisms and evolutionary rules of quantal light information sampling and integration, which underlie light adaptation and further improve our understanding of insect vision.
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Affiliation(s)
- Zhuoyi Song
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, 200433, China; Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence (Fudan University), Ministry of Education, China; MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200433, China; Zhangjiang Fudan International Innovation Center, Shanghai, China.
| | - Yu Zhou
- School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Preston PR1 2HE, UK
| | - Jianfeng Feng
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, 200433, China; Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence (Fudan University), Ministry of Education, China; MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200433, China; Zhangjiang Fudan International Innovation Center, Shanghai, China
| | - Mikko Juusola
- Department of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK; State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China.
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34
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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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35
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Lian Y, Almasi A, Grayden DB, Kameneva T, Burkitt AN, Meffin H. Learning receptive field properties of complex cells in V1. PLoS Comput Biol 2021; 17:e1007957. [PMID: 33651790 PMCID: PMC7954310 DOI: 10.1371/journal.pcbi.1007957] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 03/12/2021] [Accepted: 02/09/2021] [Indexed: 11/24/2022] Open
Abstract
There are two distinct classes of cells in the primary visual cortex (V1): simple cells and complex cells. One defining feature of complex cells is their spatial phase invariance; they respond strongly to oriented grating stimuli with a preferred orientation but with a wide range of spatial phases. A classical model of complete spatial phase invariance in complex cells is the energy model, in which the responses are the sum of the squared outputs of two linear spatially phase-shifted filters. However, recent experimental studies have shown that complex cells have a diverse range of spatial phase invariance and only a subset can be characterized by the energy model. While several models have been proposed to explain how complex cells could learn to be selective to orientation but invariant to spatial phase, most existing models overlook many biologically important details. We propose a biologically plausible model for complex cells that learns to pool inputs from simple cells based on the presentation of natural scene stimuli. The model is a three-layer network with rate-based neurons that describes the activities of LGN cells (layer 1), V1 simple cells (layer 2), and V1 complex cells (layer 3). The first two layers implement a recently proposed simple cell model that is biologically plausible and accounts for many experimental phenomena. The neural dynamics of the complex cells is modeled as the integration of simple cells inputs along with response normalization. Connections between LGN and simple cells are learned using Hebbian and anti-Hebbian plasticity. Connections between simple and complex cells are learned using a modified version of the Bienenstock, Cooper, and Munro (BCM) rule. Our results demonstrate that the learning rule can describe a diversity of complex cells, similar to those observed experimentally. Many cortical functions originate from the learning ability of the brain. How the properties of cortical cells are learned is vital for understanding how the brain works. There are many models that explain how V1 simple cells can be learned. However, how V1 complex cells are learned still remains unclear. In this paper, we propose a model of learning in complex cells based on the Bienenstock, Cooper, and Munro (BCM) rule. We demonstrate that properties of receptive fields of complex cells can be learned using this biologically plausible learning rule. Quantitative comparisons between the model and experimental data are performed. Results show that model complex cells can account for the diversity of complex cells found in experimental studies. In summary, this study provides a plausible explanation for how complex cells can be learned using biologically plausible plasticity mechanisms. Our findings help us to better understand biological vision processing and provide us with insights into the general signal processing principles that the visual cortex employs to process visual information.
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Affiliation(s)
- Yanbo Lian
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Australia
- * E-mail:
| | - Ali Almasi
- National Vision Research Institute, The Australian College of Optometry, Melbourne, Australia
| | - David B. Grayden
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Australia
| | - Tatiana Kameneva
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Australia
- Faculty of Science, Engineering and Technology, Swinburne University, Melbourne, Australia
| | - Anthony N. Burkitt
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Australia
| | - Hamish Meffin
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Australia
- National Vision Research Institute, The Australian College of Optometry, Melbourne, Australia
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
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36
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Image luminance changes contrast sensitivity in visual cortex. Cell Rep 2021; 34:108692. [PMID: 33535047 PMCID: PMC7886026 DOI: 10.1016/j.celrep.2021.108692] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/16/2020] [Accepted: 01/04/2021] [Indexed: 12/21/2022] Open
Abstract
Accurate measures of contrast sensitivity are important for evaluating visual disease progression and for navigation safety. Previous measures suggested that cortical contrast sensitivity was constant across widely different luminance ranges experienced indoors and outdoors. Against this notion, here, we show that luminance range changes contrast sensitivity in both cat and human cortex, and the changes are different for dark and light stimuli. As luminance range increases, contrast sensitivity increases more within cortical pathways signaling lights than those signaling darks. Conversely, when the luminance range is constant, light-dark differences in contrast sensitivity remain relatively constant even if background luminance changes. We show that a Naka-Rushton function modified to include luminance range and light-dark polarity accurately replicates both the statistics of light-dark features in natural scenes and the cortical responses to multiple combinations of contrast and luminance. We conclude that differences in light-dark contrast increase with luminance range and are largest in bright environments.
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Yedutenko M, Howlett MHC, Kamermans M. High Contrast Allows the Retina to Compute More Than Just Contrast. Front Cell Neurosci 2021; 14:595193. [PMID: 33519381 PMCID: PMC7843368 DOI: 10.3389/fncel.2020.595193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 12/22/2020] [Indexed: 11/29/2022] Open
Abstract
The goal of sensory processing is to represent the environment of an animal. All sensory systems share a similar constraint: they need to encode a wide range of stimulus magnitudes within their narrow neuronal response range. The most efficient way, exploited by even the simplest nervous systems, is to encode relative changes in stimulus magnitude rather than the absolute magnitudes. For instance, the retina encodes contrast, which are the variations of light intensity occurring in time and in space. From this perspective, it is easy to understand why the bright plumage of a moving bird gains a lot of attention, while an octopus remains motionless and mimics its surroundings for concealment. Stronger contrasts simply cause stronger visual signals. However, the gains in retinal performance associated with higher contrast are far more than what can be attributed to just a trivial linear increase in signal strength. Here we discuss how this improvement in performance is reflected throughout different parts of the neural circuitry, within its neural code and how high contrast activates many non-linear mechanisms to unlock several sophisticated retinal computations that are virtually impossible in low contrast conditions.
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Affiliation(s)
- Matthew Yedutenko
- Retinal Signal Processing Lab, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | - Marcus H. C. Howlett
- Retinal Signal Processing Lab, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | - Maarten Kamermans
- Retinal Signal Processing Lab, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
- Department of Biomedical Physics and Biomedical Optics, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, Netherlands
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Kozak A, Wieteska M, Ninghetto M, Szulborski K, Gałecki T, Szaflik J, Burnat K. Motion-Based Acuity Task: Full Visual Field Measurement of Shape and Motion Perception. Transl Vis Sci Technol 2021; 10:9. [PMID: 33505776 PMCID: PMC7794260 DOI: 10.1167/tvst.10.1.9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 11/19/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose Damage of retinal representation of the visual field affects its local features and the spared, unaffected parts. Measurements of visual deficiencies in ophthalmological patients are separated for central (shape) or peripheral (motion and space perception) properties, and acuity tasks rely on stationary stimuli. We explored the benefit of measuring shape and motion perception simultaneously using a new motion-based acuity task. Methods Eight healthy control subjects, three patients with retinitis pigmentosa (RP; tunnel vision), and 2 patients with Stargardt disease (STGD) juvenile macular degeneration were included. To model the peripheral loss, we narrowed the visual field in controls to 10 degrees. Negative and positive contrast of motion signals were tested in random-dot kinematograms (RDKs), where shapes were separated from the background by the motion of dots based on coherence, direction, or velocity. The task was to distinguish a circle from an ellipse. The difficulty of the task increased as ellipse became more circular until reaching the acuity limit. Results High velocity, negative contrast was more difficult for all, and for patients with STGD, it was too difficult to participate. A slower velocity improved acuity for all participants. Conclusions Proposed acuity testing not only allows for the full assessment of vision but also advances the capability of standard testing with the potential to detect spare visual functions. Translational Relevance The motion-based acuity task might be a practical tool for assessing vision loss and revealing undetected, undamaged, or strengthened properties of the injured visual system by standard testing, as suggested here for two patients with STGD and three patients with RP.
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Affiliation(s)
- Anna Kozak
- Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Michał Wieteska
- Institute of Radioelectronics and Multimedia Technology, Warsaw University of Technology, Warsaw, Poland
| | - Marco Ninghetto
- Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Kamil Szulborski
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Tomasz Gałecki
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Jacek Szaflik
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Kalina Burnat
- Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
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Kang JH, Jang YJ, Kim T, Lee BC, Lee SH, Im M. Electric Stimulation Elicits Heterogeneous Responses in ON but Not OFF Retinal Ganglion Cells to Transmit Rich Neural Information. IEEE Trans Neural Syst Rehabil Eng 2021; 29:300-309. [PMID: 33395394 DOI: 10.1109/tnsre.2020.3048973] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Retinal implants electrically stimulate surviving retinal neurons to restore vision in people blinded by outer retinal degeneration. Although the healthy retina is known to transmit a vast amount of visual information to the brain, it has not been studied whether prosthetic vision contains a similar amount of information. Here, we assessed the neural information transmitted by population responses arising in brisk transient (BT) and brisk sustained (BS) subtypes of ON and OFF retinal ganglion cells (RGCs) in the rabbit retina. To correlate the response heterogeneity and the information transmission, we first quantified the cell-to-cell heterogeneity by calculating the spike time tiling coefficient (STTC) across spiking patterns of RGCs in each type. Then, we computed the neural information encoded by the RGC population in a given type. In responses to light stimulation, spiking activities were more heterogeneous in OFF than ON RGCs (STTCAVG = 0.36, 0.45, 0.77 and 0.55 for OFF BT, OFF BS, ON BT, and ON BS, respectively). Interestingly, however, in responses to electric stimulation, both BT and BS subtypes of OFF RGCs showed remarkably homogeneous spiking patterns across cells (STTCAVG = 0.93 and 0.82 for BT and BS, respectively), whereas the two subtypes of ON RGCs showed slightly increased populational heterogeneity compared to light-evoked responses (STTCAVG = 0.71 and 0.63 for BT and BS, respectively). Consequently, the neural information encoded by the electrically-evoked responses of a population of 15 RGCs was substantially lower in the OFF than the ON pathway: OFF BT and BS cells transmit only ~23% and ~53% of the neural information transmitted by their ON counterparts. Together with previously-reported natural spiking activities in ON RGCs, the higher neural information may make ON responses more recognizable, eliciting the biased percepts of bright phosphenes.
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40
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Ahn J, Yoo Y, Goo YS. Spike-triggered Clustering for Retinal Ganglion Cell Classification. Exp Neurobiol 2020; 29:433-452. [PMID: 33321473 PMCID: PMC7788309 DOI: 10.5607/en20029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 11/19/2022] Open
Abstract
Retinal ganglion cells (RGCs), the retina's output neurons, encode visual information through spiking. The RGC receptive field (RF) represents the basic unit of visual information processing in the retina. RFs are commonly estimated using the spike-triggered average (STA), which is the average of the stimulus patterns to which a given RGC is sensitive. Whereas STA, based on the concept of the average, is simple and intuitive, it leaves more complex structures in the RFs undetected. Alternatively, spike-triggered covariance (STC) analysis provides information on second-order RF statistics. However, STC is computationally cumbersome and difficult to interpret. Thus, the objective of this study was to propose and validate a new computational method, called spike-triggered clustering (STCL), specific for multimodal RFs. Specifically, RFs were fit with a Gaussian mixture model, which provides the means and covariances of multiple RF clusters. The proposed method recovered bipolar stimulus patterns in the RFs of ON-OFF cells, while the STA identified only ON and OFF RGCs, and the remaining RGCs were labeled as unknown types. In contrast, our new STCL analysis distinguished ON-OFF RGCs from the ON, OFF, and unknown RGC types classified by STA. Thus, the proposed method enables us to include ON-OFF RGCs prior to retinal information analysis.
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Affiliation(s)
- Jungryul Ahn
- Department of Physiology, Chungbuk National University School of Medicine, Cheongju 28644, Korea
| | - Yongseok Yoo
- Department of Electronics Engineering, Incheon National University, Incheon 22012, Korea
| | - Yong Sook Goo
- Department of Physiology, Chungbuk National University School of Medicine, Cheongju 28644, Korea
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41
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Functional-pathway-dominant contrast adaptation and sensitization in mouse retinal ganglion cells. Cogn Neurodyn 2020; 14:757-767. [PMID: 33101529 DOI: 10.1007/s11571-020-09636-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 09/03/2020] [Accepted: 09/14/2020] [Indexed: 10/23/2022] Open
Abstract
Retinal ganglion cells (RGCs) reduce their light sensitivity during persistent high-contrast stimulation to prevent saturation to strong inputs and improve coding efficiency. This process is known as contrast adaptation. However, contrast adaptation also reduces RGCs' light response to weak inputs. On the other hand, some RGCs undergo contrast sensitization, and these RGCs respond to weak inputs following high contrast stimulation. In the present study, multi-electrode recordings were conducted on isolated mouse retinas under full-field visual stimulation with different contrast levels. Adaptation and sensitization were mainly observed in OFF and ON pathways, respectively. The results of linear-nonlinear analysis and stimulus reconstruction revealed that both the light sensitivity and encoded information were changed in opposite directions in adaptation and sensitization processes. Our work suggests that contrast adaptation and sensitization are two opposite dynamic processes. In mouse retina, OFF RGCs utilize adaptation to increase the discrimination of strong OFF inputs. On the other hand, ON RGCs use sensitization to increase the sensitivity to weak ON inputs. This functional differentiation might be meaningful for the mouse's survival as it lives in environments in which strong OFF stimuli often indicate potential predators while weak ON stimuli are usually related to movement and might be important for predation.
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42
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Norcia AM, Yakovleva A, Hung B, Goldberg JL. Dynamics of Contrast Decrement and Increment Responses in Human Visual Cortex. Transl Vis Sci Technol 2020; 9:6. [PMID: 32953246 PMCID: PMC7476656 DOI: 10.1167/tvst.9.10.6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 08/10/2020] [Indexed: 12/11/2022] Open
Abstract
Purpose The goal of the present experiments was to determine whether electrophysiologic response properties of the ON and OFF visual pathways observed in animal experimental models can be observed in humans. Methods Steady-state visual evoked potentials (SSVEPs) were recorded in response to equivalent magnitude contrast increments and decrements presented within a probe-on-pedestal Westheimer sensitization paradigm. The probes were modulated with sawtooth temporal waveforms at a temporal frequency of 3 or 2.73 Hz. SSVEP response waveforms and response spectra for incremental and decremental stimuli were analyzed as a function of stimulus size and visual field location in 67 healthy adult participants. Results SSVEPs recorded at the scalp differ between contrast decrements and increments of equal Weber contrast: SSVEP responses were larger in amplitude and shorter in latency for contrast decrements than for contrast increments. Both increment and decrement responses were larger for displays that were scaled for cortical magnification. Conclusions In a fashion that parallels results from the early visual system of cats and monkeys, two key properties of ON versus OFF pathways found in single-unit recordings are recapitulated at the population level of activity that can be observed with scalp electrodes, allowing differential assessment of ON and OFF pathway activity in human. Translational Relevance As data from preclinical models of visual pathway dysfunction point to differential damage to subtypes of retinal ganglion cells, this approach may be useful in future work on disease detection and treatment monitoring.
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Affiliation(s)
- Anthony M Norcia
- Department of Psychology, Stanford University, Stanford, CA, USA
| | | | - Bethany Hung
- Johns Hopkins University School of Medicine, Baltimore, MD, USA
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43
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Abstract
At various stages of the visual system, visual responses are modulated by arousal. Here, we find that in mice this modulation operates as early as in the first synapse from the retina and even in retinal axons. To measure retinal activity in the awake, intact brain, we imaged the synaptic boutons of retinal axons in the superior colliculus. Their activity depended not only on vision but also on running speed and pupil size, regardless of retinal illumination. Arousal typically reduced their visual responses and selectivity for direction and orientation. Recordings from retinal axons in the optic tract revealed that arousal modulates the firing of some retinal ganglion cells. Arousal had similar effects postsynaptically in colliculus neurons, independent of activity in the other main source of visual inputs to the colliculus, the primary visual cortex. These results indicate that arousal modulates activity at every stage of the mouse visual system.
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44
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Tesileanu T, Conte MM, Briguglio JJ, Hermundstad AM, Victor JD, Balasubramanian V. Efficient coding of natural scene statistics predicts discrimination thresholds for grayscale textures. eLife 2020; 9:e54347. [PMID: 32744505 PMCID: PMC7494356 DOI: 10.7554/elife.54347] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 07/31/2020] [Indexed: 11/13/2022] Open
Abstract
Previously, in Hermundstad et al., 2014, we showed that when sampling is limiting, the efficient coding principle leads to a 'variance is salience' hypothesis, and that this hypothesis accounts for visual sensitivity to binary image statistics. Here, using extensive new psychophysical data and image analysis, we show that this hypothesis accounts for visual sensitivity to a large set of grayscale image statistics at a striking level of detail, and also identify the limits of the prediction. We define a 66-dimensional space of local grayscale light-intensity correlations, and measure the relevance of each direction to natural scenes. The 'variance is salience' hypothesis predicts that two-point correlations are most salient, and predicts their relative salience. We tested these predictions in a texture-segregation task using un-natural, synthetic textures. As predicted, correlations beyond second order are not salient, and predicted thresholds for over 300 second-order correlations match psychophysical thresholds closely (median fractional error <0.13).
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Affiliation(s)
| | - Mary M Conte
- Feil Family Brain and Mind Institute, Weill Cornell Medical CollegeNew YorkUnited States
| | | | | | - Jonathan D Victor
- Feil Family Brain and Mind Institute, Weill Cornell Medical CollegeNew YorkUnited States
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45
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Robles E, Fields NP, Baier H. The zebrafish visual system transmits dimming information via multiple segregated pathways. J Comp Neurol 2020; 529:539-552. [PMID: 32484919 DOI: 10.1002/cne.24964] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 11/11/2022]
Abstract
Vertebrate retinas contain circuits specialized to encode light level decrements. This information is transmitted to the brain by dimming-sensitive OFF retinal ganglion cells (OFF-RGCs) that respond to light decrements with increased firing. It is known that OFF-RGCs with distinct photosensitivity profiles form parallel visual channels to the vertebrate brain, yet how these channels are processed by first- and higher order brain areas has not been well characterized in any species. To address this question in the larval zebrafish visual system, we examined the visual response properties of a genetically identified population of tectal neurons with a defined axonal projection to a second-order visual area: id2b:gal4-positive torus longitudinalis projection neurons (TLPNs). TLPNs responded consistently to whole-field dimming stimuli and exhibited the strongest responses when dimming was preceded by low light levels. Functional characterization of OFF-RGC terminals in tectum revealed responses that varied in their photosensitivities: (a) low-sensitivity OFF-RGCs that selectively respond to large light decrements, (b) high-sensitivity OFF-RGCs that selectively encode small decrements, and (c) broad sensitivity OFF-RGCs that respond to a wide range of light decrements. Diverse photosensitivity profiles were also observed using pan-neuronal calcium imaging to identify dimming-responsive neurons in both tectum and torus longitudinalis. Together, these data support a model in which parallel OFF channels generated in the retina remain segregated across three stages of visual processing. Segregated OFF channels with different sensitivities may allow specific aspects of dimming-evoked behaviors to be modulated by ambient light levels.
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Affiliation(s)
- Estuardo Robles
- Department of Biological Sciences and Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana, USA
| | - Nicholas P Fields
- Department of Biological Sciences and Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana, USA
| | - Herwig Baier
- Max Planck Institute for Neurobiology, Martinsried, Germany
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46
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Jansen M, Jin J, Li X, Lashgari R, Kremkow J, Bereshpolova Y, Swadlow HA, Zaidi Q, Alonso JM. Cortical Balance Between ON and OFF Visual Responses Is Modulated by the Spatial Properties of the Visual Stimulus. Cereb Cortex 2020; 29:336-355. [PMID: 30321290 PMCID: PMC6294412 DOI: 10.1093/cercor/bhy221] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Indexed: 11/12/2022] Open
Abstract
The primary visual cortex of carnivores and primates is dominated by the OFF visual pathway and responds more strongly to dark than light stimuli. Here, we demonstrate that this cortical OFF dominance is modulated by the size and spatial frequency of the stimulus in awake primates and we uncover a main neuronal mechanism underlying this modulation. We show that large grating patterns with low spatial frequencies drive five times more OFF-dominated than ON-dominated neurons, but this pronounced cortical OFF dominance is strongly reduced when the grating size decreases and the spatial frequency increases, as when the stimulus moves away from the observer. We demonstrate that the reduction in cortical OFF dominance is not caused by a selective reduction of visual responses in OFF-dominated neurons but by a change in the ON/OFF response balance of neurons with diverse receptive field properties that can be ON or OFF dominated, simple, or complex. We conclude that cortical OFF dominance is continuously adjusted by a neuronal mechanism that modulates ON/OFF response balance in multiple cortical neurons when the spatial properties of the visual stimulus change with viewing distance and/or optical blur.
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Affiliation(s)
- Michael Jansen
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA
| | - Jianzhong Jin
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA
| | - Xiaobing Li
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA
| | - Reza Lashgari
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA.,Brain Engineering Research Center, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
| | - Jens Kremkow
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA.,Neuroscience Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Harvey A Swadlow
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA.,Department of Psychology, University of Connecticut, Storrs, CT, USA
| | - Qasim Zaidi
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA
| | - Jose-Manuel Alonso
- Department of Biological and Vision Sciences, Biol. Sci., SUNY College of Optometry, New York, NY, USA.,Department of Psychology, University of Connecticut, Storrs, CT, USA
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47
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Ramamurthy DL, Recanzone GH. Age-related changes in sound onset and offset intensity coding in auditory cortical fields A1 and CL of rhesus macaques. J Neurophysiol 2020; 123:1015-1025. [PMID: 31995426 DOI: 10.1152/jn.00373.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Inhibition plays a key role in shaping sensory processing in the central auditory system and has been implicated in sculpting receptive field properties such as sound intensity coding and also in shaping temporal patterns of neuronal firing such as onset- or offset-evoked responses. There is substantial evidence supporting a decrease in inhibition throughout the ascending auditory pathway in geriatric animals. We therefore examined intensity coding of onset (ON) and offset (OFF) responses in auditory cortex of aged and young monkeys. A large proportion of cells in the primary auditory cortex (A1) and the caudolateral field (CL) displayed nonmonotonic rate-level functions for OFF responses in addition to nonmonotonic coding of ON responses. Aging differentially affected ON and OFF responses; the magnitude of effects was generally greater for ON responses. In addition to higher firing rates, neurons in old monkeys exhibited a significant increase in the proportion of monotonic rate-level functions and had higher best intensities than those in young monkeys. OFF responses in young monkeys displayed a range of intensity coding relationships with ON responses of the same cells, ranging from highly similar to highly dissimilar. Dissimilarity in ON/OFF coding was greater in CL and was reduced with aging, which was largely explained by a preferential decrease in the percentage of cells with nonmonotonic coding of ON and OFF responses. The changes we observed are consistent with previously demonstrated alterations in inhibition in the ascending auditory pathway of primates and could be involved in age-related deficits in the temporal processing of sounds.NEW & NOTEWORTHY Aging has a major impact on intensity coding of neurons in auditory cortex of rhesus macaques. Neural responses to sound onset and offset were affected to different extents, and their rate-level functions became more mutually similar, which could be accounted for by the loss of nonmonotonic intensity coding in geriatric monkeys. These findings were consistent with weakened inhibition in the central auditory system and could contribute to auditory processing deficits in elderly subjects.
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Affiliation(s)
| | - Gregg H Recanzone
- Center for Neuroscience, University of California, Davis, California.,Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California
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48
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Matulis CA, Chen J, Gonzalez-Suarez AD, Behnia R, Clark DA. Heterogeneous Temporal Contrast Adaptation in Drosophila Direction-Selective Circuits. Curr Biol 2020; 30:222-236.e6. [PMID: 31928874 PMCID: PMC7003801 DOI: 10.1016/j.cub.2019.11.077] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/06/2019] [Accepted: 11/26/2019] [Indexed: 11/23/2022]
Abstract
In visual systems, neurons adapt both to the mean light level and to the range of light levels, or the contrast. Contrast adaptation has been studied extensively, but it remains unclear how it is distributed among neurons in connected circuits, and how early adaptation affects subsequent computations. Here, we investigated temporal contrast adaptation in neurons across Drosophila's visual motion circuitry. Several ON-pathway neurons showed strong adaptation to changes in contrast over time. One of these neurons, Mi1, showed almost complete adaptation on fast timescales, and experiments ruled out several potential mechanisms for its adaptive properties. When contrast adaptation reduced the gain in ON-pathway cells, it was accompanied by decreased motion responses in downstream direction-selective cells. Simulations show that contrast adaptation can substantially improve motion estimates in natural scenes. The benefits are larger for ON-pathway adaptation, which helps explain the heterogeneous distribution of contrast adaptation in these circuits.
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Affiliation(s)
- Catherine A Matulis
- Department of Physics, Yale University, 217 Prospect Street, New Haven, CT 06511, USA
| | - Juyue Chen
- Interdepartmental Neuroscience Program, Yale University, 333 Cedar Street, New Haven, CT 06510, USA
| | | | - Rudy Behnia
- Department of Neuroscience, Columbia University, 3227 Broadway, New York, NY 10027, USA
| | - Damon A Clark
- Department of Physics, Yale University, 217 Prospect Street, New Haven, CT 06511, USA; Interdepartmental Neuroscience Program, Yale University, 333 Cedar Street, New Haven, CT 06510, USA; Department of Molecular, Cellular, and Developmental Biology, Yale University, 260 Whitney Avenue, New Haven, CT 06511, USA; Department of Neuroscience, Yale University, 333 Cedar Street, New Haven, CT 06510, USA.
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49
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Wang M, Aleman AC, Schaeffel F. Probing the Potency of Artificial Dynamic ON or OFF Stimuli to Inhibit Myopia Development. Invest Ophthalmol Vis Sci 2019; 60:2599-2611. [PMID: 31219534 DOI: 10.1167/iovs.18-26471] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To determine whether equiluminant artificial dynamic ON or OFF stimuli on a computer screen can induce bidirectional changes in choroidal thickness (ChTh) in both humans and chickens, and whether such changes are associated with bidirectional changes in retinal dopamine release in chickens. Methods Experiment 1: Before and after ON or OFF stimulation for 1 hour, ChTh was measured with optical coherence tomography (OCT). Experiment 2: chicks (n = 14) were raised under ON or OFF stimulation for 3 hours. ChTh was determined by OCT. Experiment 3: chicks were raised for 7 days either under room light (500 lux, n = 11), dynamic ON stimulus (700 lux, n = 15), or dynamic OFF stimulus (700 lux, n = 7). In addition, negative lenses were attached to their right eyes. After experiments 2 and 3, retinal and vitreal dopamine (DA), and its metabolites, were measured by HPLC-electrochemical detection. Results Experiment 1: Dynamic ON stimuli caused thicker choroids (+5.3 ± 2.0 μm), whereas OFF stimuli caused choroidal thinning (-4.7 ± 0.5 μm) (right eye data only, P < 0.001). Experiment 2: After 3 hours, chickens developed thicker choroids with ON stimuli (+37.4 ± 12.4 μm) and thinner choroids with OFF stimuli (-11.3 ± 3.6 μm, difference P < 0.01). Vitreal DA, 3-methoxytyramine, and homovanillic acid levels were elevated after ON stimulation, compared with the OFF (P < 0.05). Experiment 3: After 7 days, chickens with lenses developed more myopia both with ON and OFF stimulation, compared with room light. ON stimulation increased vitreal DA compared with OFF. Conclusions Artificial dynamic ON or OFF stimuli had similar effects on ChTh in humans and chickens, but more work will be necessary to determine whether such stimuli can be used as novel interventions of myopia.
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Affiliation(s)
- Min Wang
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Hunan Province, China.,Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, Germany
| | - Andrea C Aleman
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, Germany
| | - Frank Schaeffel
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, Germany
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50
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Khani A, Mustafar F, Rainer G. Distinct Frequency Specialization for Detecting Dark Transients in Humans and Tree Shrews. Cell Rep 2019; 23:2405-2415. [PMID: 29791851 DOI: 10.1016/j.celrep.2018.04.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 02/23/2018] [Accepted: 04/13/2018] [Indexed: 10/16/2022] Open
Abstract
Despite well-known privileged perception of dark over light stimuli, it is unknown to what extent this dark dominance is maintained when visual transients occur in rapid succession, for example, during perception of moving stimuli. Here, we address this question using dark and light transients presented at different flicker frequencies. Although both human participants and tree shrews exhibited dark dominance for temporally modulated transients, these occurred at different flicker frequencies, namely, at 11 Hz in humans and 40 Hz and higher in tree shrews. Tree shrew V1 neuronal activity confirmed that differences between light and dark flicker were maximal at 40 Hz, corresponding closely to behavioral findings. These findings suggest large differences in flicker perception between humans and tree shrews, which may be related to the lifestyle of these species. A specialization for detecting dark transients at high temporal frequencies may thus be adaptive for tree shrews, which are particularly fast-moving small mammals.
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Affiliation(s)
- Abbas Khani
- Visual Cognition Laboratory, Department of Medicine, University of Fribourg, 1700 Fribourg, Switzerland; Functional Brain Mapping Laboratory, Department of Basic Neurosciences, University of Geneva, 1211 Geneva, Switzerland.
| | - Faiz Mustafar
- Visual Cognition Laboratory, Department of Medicine, University of Fribourg, 1700 Fribourg, Switzerland; Department of Neurosciences, Universiti Sains Malaysia, 16150 Kelantan, Malaysia
| | - Gregor Rainer
- Visual Cognition Laboratory, Department of Medicine, University of Fribourg, 1700 Fribourg, Switzerland.
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