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Maule JJ, Maguire R, Timmis MA, Runswick OR, Wilkins L, Mann DL, Dain SJ, Bosten JM, Allen PM. Difficult at dusk? Illuminating the debate on cricket ball visibility. J Sci Med Sport 2024; 27:408-414. [PMID: 38423830 DOI: 10.1016/j.jsams.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 12/20/2023] [Accepted: 02/09/2024] [Indexed: 03/02/2024]
Abstract
OBJECTIVES Investigate the visibility of new and old red, white and pink cricket balls under lighting and background conditions experienced during a day-night cricket match. DESIGN We modelled the luminance contrast signals available for a typical observer for a ball against backgrounds in a professional cricket ground, at different times of day. METHODS Spectral reflectance (light reflected as a function of wavelength) was derived from laboratory measurements of new and old red, white and pink balls. We also gathered spectral measurements from backgrounds (pitch, grass, sightscreens, crowd, sky) and spectral illuminance during a day-night match (natural afternoon light, through dusk to night under floodlights) from Lord's Cricket Ground (London, UK). The luminance contrast of the ball relative to the background was calculated for each combination of ball, time of day, and background surface. RESULTS Old red and old pink balls may offer little or no contrast against the grass, pitch and crowd. New pink balls can also be of low contrast against the crowd at dusk, as can pink and white balls (of any age) against the sky at dusk. CONCLUSIONS Reports of difficulties with visibility of the pink ball are supported by our data. However, our modelling also shows that difficulties with visibility may also be expected under certain circumstances for red and white balls. The variable conditions in a cricket ground and the changing colour of an ageing ball make maintaining good visibility of the ball a challenge when playing day-night matches.
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Affiliation(s)
| | - Robert Maguire
- Vision and Hearing Sciences Research Centre, Anglia Ruskin University, UK
| | - Matthew A Timmis
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, UK
| | - Oliver R Runswick
- Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Luke Wilkins
- Sport, Performance, and Nutrition (SPAN) Research Group, La Trobe University, Australia
| | - David L Mann
- Department of Human Movement Sciences, Amsterdam Movement Sciences and Institute of Brain and Behaviour Amsterdam, Vrije Universiteit Amsterdam, the Netherlands
| | - Stephen J Dain
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | | | - Peter M Allen
- Vision and Hearing Sciences Research Centre, Anglia Ruskin University, UK
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2
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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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3
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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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5
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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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6
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Tang VTS, Symons RCA, Fourlanos S, Guest D, McKendrick AM. Contrast Increment and Decrement Processing in Individuals With and Without Diabetes. Invest Ophthalmol Vis Sci 2023; 64:26. [PMID: 37083950 PMCID: PMC10132322 DOI: 10.1167/iovs.64.4.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023] Open
Abstract
Purpose Animal models suggest that ON retinal ganglion cells (RGCs) may be more vulnerable to diabetic insult than OFF cells. Using three psychophysical tasks to infer the function of ON and OFF RGCs, we hypothesized that functional responses to contrast increments will be preferentially affected in early diabetes mellitus (DM) compared to contrast decrement responses. Methods Fifty-two people with DM (type 1 or type 2) (mean age = 34.8 years, range = 18-60 years) and 48 age-matched controls (mean age = 35.4 years, range = 18-60 years) participated. Experiment 1 measured contrast sensitivity to increments and decrements at four visual field locations. Experiments 2 and 3 measured visual temporal processing using (i) a response time (RT) task, and (ii) a temporal order judgment task. Mean RT and accuracy were collected for experiment 2, whereas experiment 3 measured temporal thresholds. Results For experiment 1, the DM group showed reduced increment and decrement contrast sensitivity (F (1, 97) = 4.04, P = 0.047) especially for the central location. For experiment 2, those with DM demonstrated slower RT and lower response accuracies to increments and decrements (increments: U = 780, P = 0.01, decrements: U = 749, P = 0.005). For experiment 3, performance was similar between groups (F (1, 91) = 2.52, P = 0.137). Conclusions When assessed cross-sectionally, nonselective functional consequences of retinal neuron damage are present in early DM, particularly for foveal testing. Whether increment-decrement functional indices relate to diabetic retinopathy (DR) progression or poorer visual prognosis in DM requires further study.
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Affiliation(s)
- Vanessa Thien Sze Tang
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
| | - Robert Charles Andrew Symons
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
- Department of Surgery, The University of Melbourne, Parkville, Australia
- Centre for Eye Research Australia, East Melbourne, Australia
- Department of Surgery, Alfred Hospital, Monash University, Australia
| | - Spiros Fourlanos
- Department Diabetes and Endocrinology, Royal Melbourne Hospital, Parkville, Australia
- Department Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, Australia
- Australian Centre for Accelerating Diabetes Innovations, The University of Melbourne, Parkville, Australia
| | - Daryl Guest
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
| | - Allison Maree McKendrick
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
- Division of Optometry, University of Western Australia, Perth, Australia
- Lions Eye Institute, Nedlands, Australia
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7
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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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8
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Ming G, Zhong H, Pei W, Gao X, Wang Y. A new grid stimulus with subtle flicker perception for user-friendly SSVEP-based BCIs. J Neural Eng 2023; 20. [PMID: 36827704 DOI: 10.1088/1741-2552/acbee0] [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: 11/16/2022] [Accepted: 02/24/2023] [Indexed: 02/26/2023]
Abstract
Objective.The traditional uniform flickering stimulation pattern shows strong steady-state visual evoked potential (SSVEP) responses and poor user experience with intense flicker perception. To achieve a balance between performance and comfort in SSVEP-based brain-computer interface (BCI) systems, this study proposed a new grid stimulation pattern with reduced stimulation area and low spatial contrast.Approach.A spatial contrast scanning experiment was conducted first to clarify the relationship between the SSVEP characteristics and the signs and values of spatial contrast. Four stimulation patterns were involved in the experiment: the ON and OFF grid stimulation patterns that separately activated the positive or negative contrast information processing pathways, the ON-OFF grid stimulation pattern that simultaneously activated both pathways, and the uniform flickering stimulation pattern that served as a control group. The contrast-intensity and contrast-user experience curves were obtained for each stimulation pattern. Accordingly, the optimized stimulation schemes with low spatial contrast (the ON-50% grid stimulus, the OFF-50% grid stimulus, and the Flicker-30% stimulus) were applied in a 12-target and a 40-target BCI speller and compared with the traditional uniform flickering stimulus (the Flicker-500% stimulus) in the evaluation of BCI performance and subjective experience.Main results.The OFF-50% grid stimulus showed comparable online performance (12-target, 2 s: 69.87 ± 0.74 vs. 69.76 ± 0.58 bits min-1, 40-target, 4 s: 57.02 ± 2.53 vs. 60.79 ± 1.08 bits min-1) and improved user experience (better comfortable level, weaker flicker perception and higher preference level) compared to the traditional Flicker-500% stimulus in both multi-targets BCI spellers.Significance.Selective activation of the negative contrast information processing pathway using the new OFF-50% grid stimulus evoked robust SSVEP responses. On this basis, high-performance and user-friendly SSVEP-based BCIs have been developed and implemented, which has important theoretical significance and application value in promoting the development of the visual BCI technology.
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Affiliation(s)
- Gege Ming
- State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Hui Zhong
- Jiangsu JITRI Brian Machine Fusion Intelligence Institute, Suzhou 215008, People's Republic of China
| | - Weihua Pei
- State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xiaorong Gao
- Department of Biomedical Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yijun Wang
- State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.,Chinese Institute for Brain Research, Beijing 102206, People's Republic of China
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9
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Hathibelagal AR, Bhutia P, Das M, Babu H, Jalali S, Takkar B, Paremeswarappa DC, Ballae Ganeshrao S. Tablet-based 'ON/OFF' pathway test can distinguish between rod- and cone-dominated diseases. Ophthalmic Physiol Opt 2023; 43:231-238. [PMID: 36416095 DOI: 10.1111/opo.13072] [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: 06/28/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 11/23/2022]
Abstract
INTRODUCTION The photopic ON pathway defect is associated with nocturnal vision loss. However, the measurement of ON function to detect a rod-dominated disease (rods affected more than cones) has not been explored. We evaluated whether the psychophysical evaluation of ON/OFF pathways can be used to distinguish cone-dominated from rod-dominated diseases. METHODS Thirty-seven patients with inherited retinal diseases were tested using the 'EyeSpeed' [iOS application] on an iPad. The test displayed a random number (1-3) of light or dark targets on a black-and-white noise background. Participants responded on a touch screen indicating the correct number of targets displayed. The outcome variables-reaction time, accuracy and performance index (speed [1/reaction time] * accuracy) to both light and dark targets were assessed for diagnostic ability using standard receiver-operating characteristic (ROC) analysis. RESULTS Mean ± standard deviation age and visual acuity for the cone- and rod-dominated groups were 25.15 ± 11.74 years, 0.80 ± 0.25 logMAR and 28.3 ± 14.29 years, 0.48 ± 0.26 logMAR, respectively. The median reaction time to light targets in rod-dominated disease [interquartile range] was 5.28 s [3.17], significantly greater than for patients with cone-dominated disease (2.07 s [0.93]; Mann-Whitney U test, p < 0.001). Amongst all of the outcome variables evaluated, the reaction time to light targets (criterion of ≥2.98 s) exhibited the highest area under the ROC curve (area = 0.89 ± 0.11; p < 0.001), with a sensitivity and specificity of 82.4% and 85% respectively. CONCLUSIONS Reaction time to light targets using the ON/OFF pathway paradigm is a valid marker to differentiate between rod- and cone-dominated retinal dystrophies. ON pathway function measured using a tablet-based test could act as a supplemental test in the diagnosis of challenging photoreceptor-specific inherited retinal diseases.
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Affiliation(s)
- Amithavikram R Hathibelagal
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India.,Professor Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
| | - Phuntsok Bhutia
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India.,Professor Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
| | - Mritunjoy Das
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India.,Professor Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
| | - Helna Babu
- Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, India.,Professor Brien Holden Eye Research Center, L V Prasad Eye Institute, Hyderabad, India
| | - Subhadra Jalali
- Srimati Kanuri Santhamma Centre for Vitreoretinal Diseases, Anant Bajaj Retina Institute, L V Prasad Eye Institute, Hyderabad, India.,Jasti V Ramanamma Children's Eye Care Centre, Child Sight Institute, L V Prasad Eye Institute, Hyderabad, India
| | - Brijesh Takkar
- Srimati Kanuri Santhamma Centre for Vitreoretinal Diseases, Anant Bajaj Retina Institute, L V Prasad Eye Institute, Hyderabad, India.,Indian Health Outcomes, Public Health, and Economics Research (IHOPE) Centre, L V Prasad Eye Institute, Hyderabad, India
| | - Deepika C Paremeswarappa
- Srimati Kanuri Santhamma Centre for Vitreoretinal Diseases, Anant Bajaj Retina Institute, 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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10
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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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11
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Faster Detection of "Darks" than "Brights" by Monkey Superior Colliculus Neurons. J Neurosci 2022; 42:9356-9371. [PMID: 36319117 PMCID: PMC9794369 DOI: 10.1523/jneurosci.1489-22.2022] [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: 08/03/2022] [Revised: 09/28/2022] [Accepted: 10/25/2022] [Indexed: 12/30/2022] Open
Abstract
Visual processing is segregated into ON and OFF channels as early as in the retina, and the superficial (output) layers of the primary visual cortex (V1) are dominated by neurons preferring dark stimuli. However, it is not clear how the timing of neural processing differs between "darks" and "brights" in general, especially in light of psychophysical evidence; it is also equally not clear how subcortical visual pathways that are critical for active orienting represent stimuli of positive (luminance increments) and negative (luminance decrements) contrast polarity. Here, we recorded from all visually-responsive neuron types in the superior colliculus (SC) of two male rhesus macaque monkeys. We presented a disk (0.51° radius) within the response fields (RFs) of neurons, and we varied, across trials, stimulus Weber contrast relative to a gray background. We also varied contrast polarity. There was a large diversity of preferences for darks and brights across the population. However, regardless of individual neural sensitivity, most neurons responded significantly earlier to dark than bright stimuli. This resulted in a dissociation between neural preference and visual response onset latency: a neuron could exhibit a weaker response to a dark stimulus than to a bright stimulus of the same contrast, but it would still have an earlier response to the dark stimulus. Our results highlight an additional candidate visual neural pathway for explaining behavioral differences between the processing of darks and brights, and they demonstrate the importance of temporal aspects in the visual neural code for orienting eye movements.SIGNIFICANCE STATEMENT Objects in our environment, such as birds flying across a bright sky, often project shadows (or images darker than the surround) on our retina. We studied how primate superior colliculus (SC) neurons visually process such dark stimuli. We found that the overall population of SC neurons represented both dark and bright stimuli equally well, as evidenced by a relatively equal distribution of neurons that were either more or less sensitive to darks. However, independent of sensitivity, the great majority of neurons detected dark stimuli earlier than bright stimuli, evidenced by a smaller response latency for the dark stimuli. Thus, SC neural response latency can be dissociated from response sensitivity, and it favors the faster detection of dark image contrasts.
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12
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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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13
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Williams B, Del Rosario J, Muzzu T, Peelman K, Coletta S, Bichler EK, Speed A, Meyer-Baese L, Saleem AB, Haider B. Spatial modulation of dark versus bright stimulus responses in the mouse visual system. Curr Biol 2021; 31:4172-4179.e6. [PMID: 34314675 PMCID: PMC8478832 DOI: 10.1016/j.cub.2021.06.094] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 05/20/2021] [Accepted: 06/30/2021] [Indexed: 01/06/2023]
Abstract
A fundamental task of the visual system is to respond to both increases and decreases of luminance with action potentials (ON and OFF responses1-4). OFF responses are stronger, faster, and more salient than ON responses in primary visual cortex (V1) of both cats5,6 and primates,7,8 but in ferrets9 and mice,10 ON responses can be stronger, weaker,11 or balanced12 in comparison to OFF responses. These discrepancies could arise from differences in species, experimental techniques, or stimulus properties, particularly retinotopic location in the visual field, as has been speculated;9 however, the role of retinotopy for ON/OFF dominance has not been systematically tested across multiple scales of neural activity within species. Here, we measured OFF versus ON responses across large portions of visual space with silicon probe and whole-cell patch-clamp recordings in mouse V1 and lateral geniculate nucleus (LGN). We found that OFF responses dominated in the central visual field, whereas ON and OFF responses were more balanced in the periphery. These findings were consistent across local field potential (LFP), spikes, and subthreshold membrane potential in V1, and were aligned with spatial biases in ON and OFF responses in LGN. Our findings reveal that retinotopy may provide a common organizing principle for spatial modulation of OFF versus ON processing in mammalian visual systems.
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Affiliation(s)
- Brice Williams
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Joseph Del Rosario
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Tomaso Muzzu
- UCL Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, London WC1H 0AP, UK
| | - Kayla Peelman
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Stefano Coletta
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Edyta K Bichler
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Anderson Speed
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Lisa Meyer-Baese
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Aman B Saleem
- UCL Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, London WC1H 0AP, UK
| | - Bilal Haider
- Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA.
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14
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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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15
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Segmenting surface boundaries using luminance cues. Sci Rep 2021; 11:10074. [PMID: 33980899 PMCID: PMC8115076 DOI: 10.1038/s41598-021-89277-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 04/16/2021] [Indexed: 12/02/2022] Open
Abstract
Segmenting scenes into distinct surfaces is a basic visual perception task, and luminance differences between adjacent surfaces often provide an important segmentation cue. However, mean luminance differences between two surfaces may exist without any sharp change in albedo at their boundary, but rather from differences in the proportion of small light and dark areas within each surface, e.g. texture elements, which we refer to as a luminance texture boundary. Here we investigate the performance of human observers segmenting luminance texture boundaries. We demonstrate that a simple model involving a single stage of filtering cannot explain observer performance, unless it incorporates contrast normalization. Performing additional experiments in which observers segment luminance texture boundaries while ignoring super-imposed luminance step boundaries, we demonstrate that the one-stage model, even with contrast normalization, cannot explain performance. We then present a Filter–Rectify–Filter model positing two cascaded stages of filtering, which fits our data well, and explains observers' ability to segment luminance texture boundary stimuli in the presence of interfering luminance step boundaries. We propose that such computations may be useful for boundary segmentation in natural scenes, where shadows often give rise to luminance step edges which do not correspond to surface boundaries.
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16
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Abstract
We investigated the dependence of perceived contrast on cone-opponent stimulus content and its spatial distribution. Participants matched a comparison patch to a light gray standard of fixed contrast. The first experiment determined the point of iso-salience for gratings, Gabors and Gaussians along cardinal directions in cone-opponent color space for two-alternative forced choice (2AFC) and adjustment tasks. No difference was found between adjustment and 2AFC tasks, meaning that adjustment tasks provide a quick and robust way to measure perceived contrast, at least for relatively large suprathreshold stimuli. In line with the differences in contrast energy between Gaussians, Gabors, and gratings, Gaussians required less contrast to achieve equal perceived salience with a standard irrespective of color. More surprisingly, bluish Gaussians were found to have higher salience than yellowish Gaussians at equal levels of contrast. Although perceived contrast of grating and Gabor patterns likely depends on spatial frequency channels that at 1 cycle-per-degree are not too dissimilarly tuned for color and luminance, for Gaussians the contribution of single-opponent neurons would be greater for color than for luminance. In a follow-up experiment, we found that the bluish/yellowish asymmetry decreased as we reduced the proportion of the lowpass non-flat contrast distribution in the stimulus, with minimal asymmetry for the stimulus with a flat contrast distribution (i.e., uniform patch). Combined, this means that differential engagement of spatial frequency channels, single-opponent and double-opponent neurons impacts on perceived contrast of chromatic suprathreshold stimuli. Perceived contrast thus provides a window into neural computations enacted by low-level cone-opponent mechanisms.
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Affiliation(s)
| | - Jasna Martinovic
- School of Psychology, University of Aberdeen, Aberdeen, UK
- Department of Psychology, School of Philosophy, Psychology and Language Sciences, University of Edinburgh, Edinburgh, UK
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17
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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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18
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Malevich T, Buonocore A, Hafed ZM. Dependence of the stimulus-driven microsaccade rate signature in rhesus macaque monkeys on visual stimulus size and polarity. J Neurophysiol 2020; 125:282-295. [PMID: 33427577 DOI: 10.1152/jn.00304.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Microsaccades have a steady rate of occurrence during maintained gaze fixation, which gets transiently modulated by abrupt sensory stimuli. Such modulation, characterized by a rapid reduction in microsaccade frequency followed by a stronger rebound phase of high microsaccade rate, is often described as the microsaccadic rate signature, owing to its stereotyped nature. Here, we investigated the impacts of stimulus polarity (luminance increments or luminance decrements relative to background luminance) and size on the microsaccadic rate signature. We presented brief, behaviorally irrelevant visual flashes consisting of large or small, white or black stimuli over an otherwise gray image background. Both large and small stimuli caused robust early microsaccadic inhibition, but postinhibition microsaccade rate rebound was significantly delayed and weakened for large stimuli when compared with small ones. Critically, small black stimuli were associated with stronger modulations in the microsaccade rate signature than small white stimuli, particularly in the postinhibition rebound phase, and black stimuli also amplified the incidence of early stimulus-directed microsaccades. Our results demonstrate that the microsaccadic rate signature is sensitive to stimulus size and polarity, and they point to dissociable neural mechanisms underlying early microsaccadic inhibition after stimulus onset and later microsaccadic rate rebound at longer times thereafter. These results also demonstrate early access of oculomotor control circuitry to diverse sensory representations, particularly for momentarily inhibiting saccade generation with short latencies.NEW & NOTEWORTHY Microsaccade rate is transiently reduced after sudden stimulus onsets, and then strongly rebounds before returning to baseline. We explored the influence of stimulus polarity (black vs. white) and size on this "rate signature." Large stimuli caused more muted microsaccadic rebound than small ones, and microsaccadic rebound was also differentially affected by black versus white stimuli, particularly with small stimuli. These results suggest dissociated neural mechanisms for microsaccadic inhibition and rebound in the microsaccadic rate signature.
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Affiliation(s)
- Tatiana Malevich
- Werner Reichardt Centre for Integrative Neuroscience, Tuebingen University, Tuebingen, Germany.,Hertie Institute for Clinical Brain Research, Tuebingen University, Tuebingen, Germany.,Graduate School of Neural and Behavioural Sciences, International Max-Planck Research School, Tuebingen University, Tuebingen, Germany
| | - Antimo Buonocore
- Werner Reichardt Centre for Integrative Neuroscience, Tuebingen University, Tuebingen, Germany.,Hertie Institute for Clinical Brain Research, Tuebingen University, Tuebingen, Germany
| | - Ziad M Hafed
- Werner Reichardt Centre for Integrative Neuroscience, Tuebingen University, Tuebingen, Germany.,Hertie Institute for Clinical Brain Research, Tuebingen University, Tuebingen, Germany
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19
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Hwang BW, Schütz AC. Idiosyncratic preferences in transparent motion and binocular rivalry are dissociable. J Vis 2020; 20:3. [PMID: 33156337 PMCID: PMC7671871 DOI: 10.1167/jov.20.12.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Previous studies revealed that there are idiosyncratic preferences to perceive certain motion directions in front during motion transparency depth rivalry (Mamassian & Wallace, 2010; Schütz, 2014). Meanwhile, other studies reported idiosyncratic preferences in binocular rivalry during the onset stage (Carter & Cavanagh, 2007; Stanley, Carter, & Forte, 2011). Here we investigated the relationship of idiosyncratic preferences in transparent motion and binocular rivalry. We presented two dot clouds that were moving in opposite directions. In the transparent motion condition, both dot clouds were presented to both eyes and participants had to report the dot cloud they perceived in front. In the binocular rivalry condition, the dot clouds were presented to different eyes and participants had to report the dominant dot cloud. There were strong idiosyncratic directional preferences in transparent motion and rather weak directional preferences in binocular rivalry. In general, binocular rivalry was dominated by biases in contrast polarity, whereas transparent motion was dominated by biases in motion direction. A circular correlation analysis showed no correlation between directional preferences in transparent motion and binocular rivalry. These findings show that idiosyncratic preferences in a visual feature can be dissociated at different stages of processing.
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Affiliation(s)
- Byung-Woo Hwang
- Allgemeine und Biologische Psychologie, Philipps-Universität Marburg, Marburg, Germany.,
| | - Alexander C Schütz
- Allgemeine und Biologische Psychologie, Philipps-Universität Marburg, Marburg, Germany.,Center for Mind, Brain and Behavior, Philipps-Universität Marburg, Marburg, Germany., https://www.uni-marburg.de/en/fb04/team-schuetz/team/alexander-schutz
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20
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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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21
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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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22
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João CAR, Scanferla L, Jansonius NM. Retinal Contrast Gain Control and Temporal Modulation Sensitivity Across the Visual Field in Glaucoma at Photopic and Mesopic Light Conditions. Invest Ophthalmol Vis Sci 2020; 60:4270-4276. [PMID: 31618763 DOI: 10.1167/iovs.19-27123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Glaucoma affects many aspects of visual performance, including adaptation, and this may depend on ambient luminance. We determine the influence of glaucoma and luminance on temporal aspects of adaptation, specifically on contrast gain control and temporal modulation sensitivity (TMS). Methods This case-control study included 12 glaucoma patients and 25 age-similar controls (50-70 years). Threshold perimetry was performed with a minimized testing grid (fovea and four peripheral locations). Stimuli (Goldmann size III 50 ms increment/decrement) were presented on a time-varying background with sinusoidally-modulated luminance (amplitude 60%; frequency 0-30 Hz; mean background luminance, 1 and 100 cd/m2). TMS (2.5-30 Hz) was measured in the same locations with a sinusoidally-modulated stimulus (Goldmann size IV, 334 ms) on a steady background (1 and 100 cd/m2). Results In healthy subjects, contrast sensitivity decreased with increasing background modulation frequency and increased again at very high frequencies, indicating contrast gain control. Minimum sensitivity was located between 2.5 and 20 Hz, depending on luminance and eccentricity. In glaucoma patients, the same frequency dependency was found (P = 0.12) but with an overall reduced sensitivity (P = 1 × 10-5), independent of luminance (P = 0.20). Decrements differentiated better between glaucoma and healthy subjects than increments (P = 0.004). TMS was reduced in glaucoma (P = 5 × 10-6) across all frequencies and luminance levels, with complete loss for high frequencies at 1 cd/m2. Conclusions Contrast gain control is largely unaffected in glaucoma, suggesting intact amacrine cell function. Perimetry with decrements or a high-frequency stimulus on a low-luminance background seems best to differentiate between glaucoma and healthy subjects.
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Affiliation(s)
- Catarina A R João
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Graduate School of Medical Sciences (Research School of Behavioural and Cognitive Neurosciences), University of Groningen, Groningen, The Netherlands
| | - Lorenzo Scanferla
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Graduate School of Medical Sciences (Research School of Behavioural and Cognitive Neurosciences), University of Groningen, Groningen, The Netherlands
| | - Nomdo M Jansonius
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Graduate School of Medical Sciences (Research School of Behavioural and Cognitive Neurosciences), University of Groningen, Groningen, The Netherlands
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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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Gheorghiu E, Kingdom FAA. Luminance-contrast properties of texture-shape and texture-surround suppression of contour shape. J Vis 2019; 19:4. [PMID: 31613953 DOI: 10.1167/19.12.4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Studies have revealed that textures suppress the processing of the shapes of contours they surround. One manifestation of texture-surround suppression is the reduction in the magnitude of adaptation-induced contour-shape aftereffects when the adaptor contour is surrounded by a texture. Here we utilize this phenomenon to investigate the nature of the first-order inputs to texture-surround suppression of contour shape by examining its selectivity to luminance polarity and the magnitude of luminance contrast. Stimuli were constructed from sinusoidal-shaped strings of either "bright" or "dark" elongated Gaussians. Observers adapted to pairs of contours, and the aftereffect was measured as the shift in the apparent shape frequency of subsequently presented test contours. We found that the suppression of the contour-shape aftereffect by a surround texture made of similar contours was maximal when the adaptor's center and surround contours were of the same polarity, revealing polarity specificity of the surround-suppression effect. We also measured the effect of varying the relative contrasts of the adaptor's center and surround and found that the reduction in the contour-shape aftereffect was determined by the surround-to-center contrast ratio. Finally, we measured the selectivity to luminance polarity of the texture-shape aftereffect itself and found that it was reduced when the adaptors and tests were of opposite luminance polarity. We conclude that texture-surround suppression of contour-shape as well as texture-shape processing itself depend on "on-off" luminance-polarity channel interactions. These selectivities may constitute an important neural substrate underlying efficient figure-ground segregation and image segmentation.
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Affiliation(s)
- Elena Gheorghiu
- Department of Psychology, University of Stirling, Stirling, Scotland, United Kingdom
| | - Frederick A A Kingdom
- Department of Ophthalmology, McGill Vision Research, McGill University, Montreal, QC, Canada
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25
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Amblyopia Affects the ON Visual Pathway More than the OFF. J Neurosci 2019; 39:6276-6290. [PMID: 31189574 PMCID: PMC6687897 DOI: 10.1523/jneurosci.3215-18.2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 06/03/2019] [Accepted: 06/05/2019] [Indexed: 02/03/2023] Open
Abstract
Visual information reaches the cerebral cortex through parallel ON and OFF pathways that signal the presence of light and dark stimuli in visual scenes. We have previously demonstrated that optical blur reduces visual salience more for light than dark stimuli because it removes the high spatial frequencies from the stimulus, and low spatial frequencies drive weaker ON than OFF cortical responses. Therefore, we hypothesized that sustained optical blur during brain development should weaken ON cortical pathways more than OFF, increasing the dominance of darks in visual perception. Here we provide support for this hypothesis in humans with anisometropic amblyopia who suffered sustained optical blur early after birth in one of the eyes. In addition, we show that the dark dominance in visual perception also increases in strabismic amblyopes that have their vision to high spatial frequencies reduced by mechanisms not associated with optical blur. Together, we show that amblyopia increases visual dark dominance by 3-10 times and that the increase in dark dominance is strongly correlated with amblyopia severity. These results can be replicated with a computational model that uses greater luminance/response saturation in ON than OFF pathways and, as a consequence, reduces more ON than OFF cortical responses to stimuli with low spatial frequencies. We conclude that amblyopia affects the ON cortical pathway more than the OFF, a finding that could have implications for future amblyopia treatments.SIGNIFICANCE STATEMENT Amblyopia is a loss of vision that affects 2-5% of children across the world and originates from a deficit in visual cortical circuitry. Current models assume that amblyopia affects similarly ON and OFF visual pathways, which signal light and dark features in visual scenes. Against this current belief, here we demonstrate that amblyopia affects the ON visual pathway more than the OFF, a finding that could have implications for new amblyopia treatments targeted at strengthening a weak ON visual pathway.
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26
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Chubb C, Chiao CC, Ulmer K, Buresch K, Birk MA, Hanlon RT. Dark scene elements strongly influence cuttlefish camouflage responses in visually cluttered environments. Vision Res 2018; 149:86-101. [PMID: 29913248 DOI: 10.1016/j.visres.2018.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 06/03/2018] [Accepted: 06/04/2018] [Indexed: 11/27/2022]
Abstract
This study investigated how cuttlefish (Sepia officinalis) camouflage patterns are influenced by the proportions of different gray-scales present in visually cluttered environments. All experimental substrates comprised spatially random arrays of texture elements (texels) of five gray-scales: Black, Dark gray, Gray, Light gray, and White. The substrates in Experiment 1 were densely packed arrays of square texels that varied over 4 sizes in different conditions. Experiment 2 used substrates in which texels were disks separated on a homogeneous background that was Black, Gray or White in different conditions. In a given condition, the histogram of texel gray-scales was varied across different substrates. For each of 16 cuttlefish pattern response statistics c, the resulting data were used to determine the strength with which variations in the proportions of different gray-scales influenced c. The main finding is that darker-than-average texels (i.e., texels of negative contrast polarity) predominate in controlling cuttlefish pattern responses in the context of cluttered substrates. In Experiment 1, for example, substrates of all four texel-sizes, activation of the cuttlefish "white square" and "white head bar" (two highly salient skin components) is strongly influenced by variations in the proportions of Black and Dark gray (but not Gray, Light gray, or White) texels. It is hypothesized that in the context of high-variance visual input characteristic of cluttered substrates in the cuttlefish natural habitat, elements of negative contrast polarity reliably signal the presence of edges produced by overlapping objects, in the presence of which disruptive pattern responses are likely to achieve effective camouflage.
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Affiliation(s)
- C Chubb
- Department of Cognitive Sciences and Institute for Mathematical Behavioral Sciences, University of California at Irvine, Irvine, CA, USA; Marine Biological Laboratory, Woods Hole, MA, USA.
| | - C-C Chiao
- Department of Life Science and Institute of Systems Neuroscience, National Tsing Hua University, 101, Sec 2, Kuang Fu Road, Hsinchu 30013, Taiwan; Marine Biological Laboratory, Woods Hole, MA, USA
| | - K Ulmer
- Marine Biological Laboratory, Woods Hole, MA, USA
| | - K Buresch
- Marine Biological Laboratory, Woods Hole, MA, USA
| | - M A Birk
- Marine Biological Laboratory, Woods Hole, MA, USA
| | - R T Hanlon
- Marine Biological Laboratory, Woods Hole, MA, USA
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27
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Motion changes response balance between ON and OFF visual pathways. Commun Biol 2018; 1:60. [PMID: 30271942 PMCID: PMC6123681 DOI: 10.1038/s42003-018-0066-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 05/03/2018] [Indexed: 11/09/2022] Open
Abstract
Humans are faster at detecting dark than light stationary stimuli, a temporal difference that originates early in the visual pathway. Here we show that this difference reverses when stimuli move, making detection faster for moving lights than darks. Human subjects judged the direction of moving edges and bars, and made faster and more accurate responses for light than for dark stimuli. This light/dark asymmetry is greatest at low speeds and disappears at high speeds. In parallel experiments, we recorded responses in the cat visual cortex for moving bars and again find that responses are faster for light bars than for dark bars moving at low speeds. We show that differences in the luminance-response function between ON and OFF pathways can reproduce these findings, and may explain why ON pathways are used for slow-motion image stabilization in many species.
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28
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Shinomori K, Panorgias A, Werner JS. Age-related changes in ON and OFF responses to luminance increments and decrements. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2018; 35:B26-B34. [PMID: 29603935 DOI: 10.1364/josaa.35.000b26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/27/2017] [Indexed: 06/08/2023]
Abstract
Impulse response functions for an incremental luminous pulse (ON flash) or a decremental luminous pulse (OFF flash) were derived for twelve young (19-24 years old) and ten old (65-84 years old) observers. Thresholds were measured for two pulses separated by stimulus-onset-asynchronies from 13.3 to 186.7 ms. The pulses had a spatial Gaussian shape and were presented as increments or decrements on a 15 cd/m2 equal-energy white background, having the same chromaticity as the pulse. A spatial four-alternative forced-choice method was combined with a staircase procedure. Retinal illuminance was equated individually by heterochromatic flicker photometry and using a 2.3-mm exit pupil in a Maxwellian-view optical system to reduce the effects of age-related changes and individual variations in lens density and pupil size. Luminance ON- and OFF-impulse response functions calculated from the threshold data revealed significant age-related changes in the response amplitude of both first excitatory and first inhibitory phases. However, there were no significant changes in the time to the first peak or the second peak. These age-related changes in luminance varying ON- and OFF-impulse response functions (IRFs), reflecting putative properties of the magnocellular pathway, are discussed in relation to motion detection and the balance of ON and OFF pathways across the life span.
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29
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Pons C, Mazade R, Jin J, Dul MW, Zaidi Q, Alonso JM. Neuronal mechanisms underlying differences in spatial resolution between darks and lights in human vision. J Vis 2017; 17:5. [PMID: 29196762 PMCID: PMC5713488 DOI: 10.1167/17.14.5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Artists and astronomers noticed centuries ago that humans perceive dark features in an image differently from light ones; however, the neuronal mechanisms underlying these dark/light asymmetries remained unknown. Based on computational modeling of neuronal responses, we have previously proposed that such perceptual dark/light asymmetries originate from a luminance/response saturation within the ON retinal pathway. Consistent with this prediction, here we show that stimulus conditions that increase ON luminance/response saturation (e.g., dark backgrounds) or its effect on light stimuli (e.g., optical blur) impair the perceptual discrimination and salience of light targets more than dark targets in human vision. We also show that, in cat visual cortex, the magnitude of the ON luminance/response saturation remains relatively constant under a wide range of luminance conditions that are common indoors, and only shifts away from the lowest luminance contrasts under low mesopic light. Finally, we show that the ON luminance/response saturation affects visual salience mostly when the high spatial frequencies of the image are reduced by poor illumination or optical blur. Because both low luminance and optical blur are risk factors in myopia, our results suggest a possible neuronal mechanism linking myopia progression with the function of the ON visual pathway.
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Affiliation(s)
- Carmen Pons
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Reece Mazade
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Jianzhong Jin
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Mitchell W Dul
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Qasim Zaidi
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Jose-Manuel Alonso
- Department of Biological and Visual Sciences, State University of New York College of Optometry, New York, NY, USA
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30
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Fat or fiction? Effects of body size, eating pathology, and sex upon the body schema of an undergraduate population. Body Image 2017; 23:135-145. [PMID: 28992582 DOI: 10.1016/j.bodyim.2017.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/24/2017] [Accepted: 09/25/2017] [Indexed: 12/19/2022]
Abstract
Although there is a growing consensus that women with anorexia nervosa have a distorted body schema, the origins of this disturbance remain uncertain. The present investigation examined the effects of body size, eating pathology, and sex upon the body schema of an at-risk, undergraduate population. In Study 1, 98 participants mentally simulated their passage through apertures. When aperture width was manipulated, narrow and broad women over- and under-estimated their spatial requirements for passage, respectively. This relationship was exacerbated by dietary restraint. When aperture height was manipulated, short and tall men over- and under-estimated their spatial requirements for passage, respectively. Study 2 (N=32) replicated the association between women's veridical and internally-represented widths, although no significant effects of eating pathology were observed. Our findings suggest that body schema enlargement is not necessarily pathological, and may be driven by normal perceptual biases and internalised sociocultural body ideals.
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Abstract
Visual textures are a class of stimuli with properties that make them well suited for addressing general questions about visual function at the levels of behavior and neural mechanism. They have structure across multiple spatial scales, they put the focus on the inferential nature of visual processing, and they help bridge the gap between stimuli that are analytically convenient and the complex, naturalistic stimuli that have the greatest biological relevance. Key questions that are well suited for analysis via visual textures include the nature and structure of perceptual spaces, modulation of early visual processing by task, and the transformation of sensory stimuli into patterns of population activity that are relevant to perception.
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Affiliation(s)
- Jonathan D Victor
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065;
| | - Mary M Conte
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065;
| | - Charles F Chubb
- Department of Cognitive Sciences, School of Social Sciences, University of California, Irvine, California 92697
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32
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Asymmetries of Dark and Bright Negative Afterimages Are Paralleled by Subcortical ON and OFF Poststimulus Responses. J Neurosci 2017; 37:1984-1996. [PMID: 28077727 DOI: 10.1523/jneurosci.2021-16.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 12/21/2016] [Accepted: 01/02/2017] [Indexed: 01/01/2023] Open
Abstract
Humans are more sensitive to luminance decrements than increments, as evidenced by lower thresholds and shorter latencies for dark stimuli. This asymmetry is consistent with results of neurophysiological recordings in dorsal lateral geniculate nucleus (dLGN) and primary visual cortex (V1) of cat and monkey. Specifically, V1 population responses demonstrate that darks elicit higher levels of activation than brights, and the latency of OFF responses in dLGN and V1 is shorter than that of ON responses. The removal of a dark or bright disc often generates the perception of a negative afterimage, and here we ask whether there also exist asymmetries for negative afterimages elicited by dark and bright discs. If so, do the poststimulus responses of subcortical ON and OFF cells parallel such afterimage asymmetries? To test these hypotheses, we performed psychophysical experiments in humans and single-cell/S-potential recordings in cat dLGN. Psychophysically, we found that bright afterimages elicited by luminance decrements are stronger and last longer than dark afterimages elicited by luminance increments of equal sizes. Neurophysiologically, we found that ON cells responded to the removal of a dark disc with higher firing rates that were maintained for longer than OFF cells to the removal of a bright disc. The ON and OFF cell asymmetry was most pronounced at long stimulus durations in the dLGN. We conclude that subcortical response strength differences between ON and OFF channels parallel the asymmetries between bright and dark negative afterimages, further supporting a subcortical origin of bright and dark afterimage perception.SIGNIFICANCE STATEMENT Afterimages are physiological aftereffects following stimulation of the eye, the study of which helps us to understand how our visual brain generates visual perception in the absence of physical stimuli. We report, for the first time to our knowledge, asymmetries between bright and dark negative afterimages elicited by luminance decrements and increments, respectively. Bright afterimages are stronger and last longer than dark afterimages. Subcortical neuronal recordings of poststimulus responses of ON and OFF cells reveal similar asymmetries with respect to response strength and duration. Our results suggest that subcortical differences between ON and OFF channels help explain intensity and duration asymmetries between bright and dark afterimages, supporting the notion of a subcortical origin of bright and dark afterimages.
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Koch E, Jin J, Alonso JM, Zaidi Q. Functional implications of orientation maps in primary visual cortex. Nat Commun 2016; 7:13529. [PMID: 27876796 PMCID: PMC5122974 DOI: 10.1038/ncomms13529] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 10/12/2016] [Indexed: 02/02/2023] Open
Abstract
Stimulus orientation in the primary visual cortex of primates and carnivores is mapped as iso-orientation domains radiating from pinwheel centres, where orientation preferences of neighbouring cells change circularly. Whether this orientation map has a function is currently debated, because many mammals, such as rodents, do not have such maps. Here we show that two fundamental properties of visual cortical responses, contrast saturation and cross-orientation suppression, are stronger within cat iso-orientation domains than at pinwheel centres. These differences develop when excitation (not normalization) from neighbouring oriented neurons is applied to different cortical orientation domains and then balanced by inhibition from un-oriented neurons. The functions of the pinwheel mosaic emerge from these local intra-cortical computations: Narrower tuning, greater cross-orientation suppression and higher contrast gain of iso-orientation cells facilitate extraction of object contours from images, whereas broader tuning, greater linearity and less suppression of pinwheel cells generate selectivity for surface patterns and textures. Stimulus orientation in the primary visual cortex of primates and carnivores is mapped into a geometrical mosaic but the functional implications of these maps remain debated. Here the authors reveal an association between the structure of cortical orientation maps in cats, and the functions of local cortical circuits in processing patterns and contours.
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Affiliation(s)
- Erin Koch
- Graduate Center for Vision Research, College of Optometry, State University of New York, 33 West 42nd Street, New York, New York 10036, USA
| | - Jianzhong Jin
- Graduate Center for Vision Research, College of Optometry, State University of New York, 33 West 42nd Street, New York, New York 10036, USA
| | - Jose M Alonso
- Graduate Center for Vision Research, College of Optometry, State University of New York, 33 West 42nd Street, New York, New York 10036, USA
| | - Qasim Zaidi
- Graduate Center for Vision Research, College of Optometry, State University of New York, 33 West 42nd Street, New York, New York 10036, USA
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Georgeson MA, Schofield AJ. Binocular functional architecture for detection of contrast-modulated gratings. Vision Res 2016; 128:68-82. [PMID: 27664349 DOI: 10.1016/j.visres.2016.09.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 09/11/2016] [Accepted: 09/12/2016] [Indexed: 10/20/2022]
Abstract
Combination of signals from the two eyes is the gateway to stereo vision. To gain insight into binocular signal processing, we studied binocular summation for luminance-modulated gratings (L or LM) and contrast-modulated gratings (CM). We measured 2AFC detection thresholds for a signal grating (0.75c/deg, 216ms) shown to one eye, both eyes, or both eyes out-of-phase. For LM and CM, the carrier noise was in both eyes, even when the signal was monocular. Mean binocular thresholds for luminance gratings (L) were 5.4dB better than monocular thresholds - close to perfect linear summation (6dB). For LM and CM the binocular advantage was again 5-6dB, even when the carrier noise was uncorrelated, anti-correlated, or at orthogonal orientations in the two eyes. Binocular combination for CM probably arises from summation of envelope responses, and not from summation of these conflicting carrier patterns. Antiphase signals produced no binocular advantage, but thresholds were about 1-3dB higher than monocular ones. This is not consistent with simple linear summation, which should give complete cancellation and unmeasurably high thresholds. We propose a three-channel model in which noisy monocular responses to the envelope are binocularly combined in a contrast-weighted sum, but also remain separately available to perception via a max operator. Vision selects the largest of the three responses. With in-phase gratings the binocular channel dominates, but antiphase gratings cancel in the binocular channel and the monocular channels mediate detection. The small antiphase disadvantage might be explained by a subtle influence of background responses on binocular and monocular detection.
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Affiliation(s)
- Mark A Georgeson
- School of Life & Health Sciences, Aston University, Birmingham B4 7ET, UK.
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35
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Sensitivity of the avian motion system to light and dark stimuli. Exp Brain Res 2016; 235:401-406. [PMID: 27743012 DOI: 10.1007/s00221-016-4786-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 09/23/2016] [Indexed: 10/20/2022]
Abstract
Global motion perception is important for mobile organisms. In laterally eyed birds, global motion appears to be processed in the entopallium, a neural structure that is part of the tectofugal pathway. Electrophysiological research has shown that motion selective cells in the entopallium are most responsive to small dark moving targets. Here, we investigated whether this bias toward dark targets of entopallial cells is mirrored by perceptual performance in a motion detection task in pigeons. We measured the detection thresholds of pigeons using random dot stimuli that consisted of either black or white dots on a gray background. We found that thresholds were significantly lower when using black dots as opposed to white dots. This heightened sensitivity is also noted in the learning rates of the pigeons. That is, we found that the pigeons learned the detection task significantly faster when the stimuli consisted of black dots. We believe that our results have important implications for the understanding of the functional role of the entopallium and the ON and OFF pathways in the avian motion system.
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36
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Pamir Z, Boyaci H. Context-dependent lightness affects perceived contrast. Vision Res 2016; 124:24-33. [PMID: 27323312 DOI: 10.1016/j.visres.2016.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/08/2016] [Accepted: 06/09/2016] [Indexed: 10/21/2022]
Abstract
Perceived contrast of a grating varies with its background (or mean) luminance: of the two gratings with the same photometric contrast the one on higher luminance background appears to have higher contrast. Does perceived contrast also vary with context-dependent background lightness even when the luminance remains constant? We investigated this question using a stimulus in which two equiluminant patches ("context squares", CSs) appear different in lightness. First we measured the lightness effect in a behavioral experiment. After ensuring that it was present for all participants, we conducted perceived contrast experiments, where participants judged the contrast of rectified incremental and decremental square-wave gratings superimposed on the CSs. For the incremental gratings participants' settings were significantly different for the two CSs. Specifically, perceived contrast was higher when the gratings were placed on the context square that was perceived lighter. In a follow-up experiment we measured perceived contrast of rectified gratings on isolated patches that differed in luminance. The pattern of results of the two experiments was consistent, demonstrating that possibly shared mechanisms underpin the effects of background luminance and context-dependent lightness on perceived contrast.
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Affiliation(s)
- Zahide Pamir
- A.S. Brain Research Center, National Magnetic Resonance Research Center (UMRAM), Neuroscience Graduate Program, Bilkent University, Ankara, Turkey.
| | - Huseyin Boyaci
- A.S. Brain Research Center, National Magnetic Resonance Research Center (UMRAM), Neuroscience Graduate Program, Bilkent University, Ankara, Turkey; Department of Psychology, Bilkent University, Ankara, Turkey; Department of Psychology, JL Gießen University, Gießen, Germany
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37
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Bachy R, Zaidi Q. Properties of lateral interaction in color and brightness induction. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2016; 33:A143-9. [PMID: 26974918 DOI: 10.1364/josaa.33.00a143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In a visual scene, when objects are surrounded by other components, neural mechanisms increase the perceived color and brightness difference between an object and its surround, potentially enhancing an observer's ability to segment objects. Despite almost two centuries of empirical investigations, the nature of induction mechanisms remains elusive. To elucidate the nature of these mechanisms, we introduce a new method for measuring color and brightness induction that allows separate manipulation of lateral interactions and adaptation, and controls for eye-movement-related effects. We use the method to examine the function relating induction magnitude to contrast change in the surround, the symmetry of induction in complementary directions for the three cardinal color axes, and the effect of blur between the test and the surround. On average, brightness induction was more linear than chromatic induction. The induction magnitude was similar for surrounds of complementary colors on average and for many conditions, and when individual observers deviated from symmetry it could be on either side. Edge blur did not change the induction magnitude. For slower presentations, light/dark induction increased to further reduce asymmetry, suggesting that previously found light/dark induction asymmetry is not due to lateral interactions or prolonged adaptation. Lateral interactions underlying induction are thus mostly symmetric for color and brightness axes and involve spatially opponent filters of modest widths, rather than edge extraction.
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Smith GB, Whitney DE, Fitzpatrick D. Modular Representation of Luminance Polarity in the Superficial Layers of Primary Visual Cortex. Neuron 2016; 88:805-18. [PMID: 26590348 DOI: 10.1016/j.neuron.2015.10.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 09/23/2015] [Accepted: 10/06/2015] [Indexed: 10/22/2022]
Abstract
The spatial arrangement of luminance increments (ON) and decrements (OFF) falling on the retina provides a wealth of information used by central visual pathways to construct coherent representations of visual scenes. But how the polarity of luminance change is represented in the activity of cortical circuits remains unclear. Using wide-field epifluorescence and two-photon imaging we demonstrate a robust modular representation of luminance polarity (ON or OFF) in the superficial layers of ferret primary visual cortex. Polarity-specific domains are found with both uniform changes in luminance and single light/dark edges, and include neurons selective for orientation and direction of motion. The integration of orientation and polarity preference is evident in the selectivity and discrimination capabilities of most layer 2/3 neurons. We conclude that polarity selectivity is an integral feature of layer 2/3 neurons, ensuring that the distinction between light and dark stimuli is available for further processing in downstream extrastriate areas.
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Affiliation(s)
- Gordon B Smith
- Department of Functional Architecture and Development of Cerebral Cortex, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - David E Whitney
- Department of Functional Architecture and Development of Cerebral Cortex, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - David Fitzpatrick
- Department of Functional Architecture and Development of Cerebral Cortex, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA.
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Zhao L, Sendek C, Davoodnia V, Lashgari R, Dul MW, Zaidi Q, Alonso JM. Effect of Age and Glaucoma on the Detection of Darks and Lights. Invest Ophthalmol Vis Sci 2015; 56:7000-6. [PMID: 26513506 DOI: 10.1167/iovs.15-16753] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We have shown previously that normal observers detect dark targets faster and more accurately than light targets, when presented in noisy backgrounds. We investigated how these differences in detection time and accuracy are affected by age and ganglion cell pathology associated with glaucoma. METHODS We asked 21 glaucoma patients, 21 age-similar controls, and 5 young control observers to report as fast as possible the number of 1 to 3 light or dark targets. The targets were positioned at random in a binary noise background, within the central 30° of the visual field. RESULTS We replicate previous findings that darks are detected faster and more accurately than lights. We extend these findings by demonstrating that differences in detection of darks and lights are found reliably across different ages and in observers with glaucoma. We show that differences in detection time increase at a rate of approximately 55 msec/dB at early stages of glaucoma and then remain constant at later stages at approximately 800 msec. In normal subjects, differences in detection time increase with age at a rate of approximately 8 msec/y. We also demonstrate that the accuracy to detect lights and darks is significantly correlated with the severity of glaucoma and that the mean detection time is significantly longer for subjects with glaucoma than age-similar controls. CONCLUSIONS We conclude that differences in detection of darks and lights can be demonstrated over a wide range of ages, and asymmetries in dark/light detection increase with age and early stages of glaucoma.
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Affiliation(s)
- Linxi Zhao
- Department of Biological and Visual Sciences State University of New York, College of Optometry, New York, New York, United States
| | - Caroline Sendek
- Department of Biological and Visual Sciences State University of New York, College of Optometry, New York, New York, United States
| | - Vandad Davoodnia
- School of Cognitive Sciences, Institute for Research in Fundamental Sciences, Tehran, Iran
| | - Reza Lashgari
- School of Cognitive Sciences, Institute for Research in Fundamental Sciences, Tehran, Iran
| | - Mitchell W Dul
- Department of Biological and Visual Sciences State University of New York, College of Optometry, New York, New York, United States
| | - Qasim Zaidi
- Department of Biological and Visual Sciences State University of New York, College of Optometry, New York, New York, United States
| | - Jose-Manuel Alonso
- Department of Biological and Visual Sciences State University of New York, College of Optometry, New York, New York, United States
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40
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Jiang Y, Purushothaman G, Casagrande VA. The functional asymmetry of ON and OFF channels in the perception of contrast. J Neurophysiol 2015; 114:2816-29. [PMID: 26334011 DOI: 10.1152/jn.00560.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 09/02/2015] [Indexed: 12/25/2022] Open
Abstract
To fully understand the relationship between perception and single neural responses, one should take into consideration the early stages of sensory processing. Few studies, however, have directly examined the neural underpinning of visual perception in the lateral geniculate nucleus (LGN), only one synapse away from the retina. In this study we recorded from LGN parvocellular (P) ON-center and OFF-center neurons while monkeys either passively viewed or actively detected a full range of contrasts. We found that OFF neurons were more sensitive in detecting negative contrasts than ON neurons were in detecting positive contrasts. Also, OFF neurons had higher spontaneous activities, higher peak response amplitudes, and were more sustained than ON neurons in their contrast responses. Puzzlingly, OFF neurons failed to show any significant correlations with the monkeys' perceptual choices, despite their greater contrast sensitivities. If, however, choice probabilities were calculated from interspike intervals instead of spike counts (thus taking into account the higher firing rates of OFF neurons), OFF neurons but not ON neurons were significantly correlated with behavioral choices. Taken together, these results demonstrate in awake, behaving animals that: 1) the ON and OFF pathways do not simply mirror each other in their functionality but instead carry qualitatively different types of information, and 2) the responses of ON and OFF neurons can be correlated with perceptual choices even in the absence of physical stimuli and interneuronal correlations.
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Affiliation(s)
- Yaoguang Jiang
- Department of Psychology, Vanderbilt University, Nashville, Tennessee
| | - Gopathy Purushothaman
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee; and
| | - Vivien A Casagrande
- Department of Psychology, Vanderbilt University, Nashville, Tennessee; Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee; and Department of Ophthalmology and Visual Sciences, Vanderbilt University, Nashville, Tennessee
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41
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Victor JD, Thengone DJ, Rizvi SM, Conte MM. A perceptual space of local image statistics. Vision Res 2015; 117:117-35. [PMID: 26130606 DOI: 10.1016/j.visres.2015.05.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 05/28/2015] [Accepted: 05/30/2015] [Indexed: 11/17/2022]
Abstract
Local image statistics are important for visual analysis of textures, surfaces, and form. There are many kinds of local statistics, including those that capture luminance distributions, spatial contrast, oriented segments, and corners. While sensitivity to each of these kinds of statistics have been well-studied, much less is known about visual processing when multiple kinds of statistics are relevant, in large part because the dimensionality of the problem is high and different kinds of statistics interact. To approach this problem, we focused on binary images on a square lattice - a reduced set of stimuli which nevertheless taps many kinds of local statistics. In this 10-parameter space, we determined psychophysical thresholds to each kind of statistic (16 observers) and all of their pairwise combinations (4 observers). Sensitivities and isodiscrimination contours were consistent across observers. Isodiscrimination contours were elliptical, implying a quadratic interaction rule, which in turn determined ellipsoidal isodiscrimination surfaces in the full 10-dimensional space, and made predictions for sensitivities to complex combinations of statistics. These predictions, including the prediction of a combination of statistics that was metameric to random, were verified experimentally. Finally, check size had only a mild effect on sensitivities over the range from 2.8 to 14min, but sensitivities to second- and higher-order statistics was substantially lower at 1.4min. In sum, local image statistics form a perceptual space that is highly stereotyped across observers, in which different kinds of statistics interact according to simple rules.
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Affiliation(s)
- Jonathan D Victor
- Brain and Mind Research Institute, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, United States.
| | - Daniel J Thengone
- Brain and Mind Research Institute, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, United States
| | - Syed M Rizvi
- Brain and Mind Research Institute, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, United States
| | - Mary M Conte
- Brain and Mind Research Institute, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, United States
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42
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Predicting cortical dark/bright asymmetries from natural image statistics and early visual transforms. PLoS Comput Biol 2015; 11:e1004268. [PMID: 26020624 PMCID: PMC4447361 DOI: 10.1371/journal.pcbi.1004268] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 03/28/2015] [Indexed: 11/19/2022] Open
Abstract
The nervous system has evolved in an environment with structure and predictability. One of the ubiquitous principles of sensory systems is the creation of circuits that capitalize on this predictability. Previous work has identified predictable non-uniformities in the distributions of basic visual features in natural images that are relevant to the encoding tasks of the visual system. Here, we report that the well-established statistical distributions of visual features -- such as visual contrast, spatial scale, and depth -- differ between bright and dark image components. Following this analysis, we go on to trace how these differences in natural images translate into different patterns of cortical input that arise from the separate bright (ON) and dark (OFF) pathways originating in the retina. We use models of these early visual pathways to transform natural images into statistical patterns of cortical input. The models include the receptive fields and non-linear response properties of the magnocellular (M) and parvocellular (P) pathways, with their ON and OFF pathway divisions. The results indicate that there are regularities in visual cortical input beyond those that have previously been appreciated from the direct analysis of natural images. In particular, several dark/bright asymmetries provide a potential account for recently discovered asymmetries in how the brain processes visual features, such as violations of classic energy-type models. On the basis of our analysis, we expect that the dark/bright dichotomy in natural images plays a key role in the generation of both cortical and perceptual asymmetries. Sensory systems must contend with a tremendous amount of diversity in the natural world. Gaining a detailed description of the natural world’s statistical regularities is a critical part of understanding how the nervous system is adapted to its environment. Here, we report that the well-established statistical distributions of basic visual features—such as visual contrast and spatial scale—diverge when separated into bright and dark components. Operations such as dark/bright segregation are key features of early visual pathways. By modeling these pathways, we demonstrate that the dark and bright visual patterns driving cortical networks are asymmetric across a number of visual features, producing previously unappreciated second-order regularities. The results provide a parsimonious account for recently discovered asymmetries in cortical activity.
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43
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Sato H, Motoyoshi I, Sato T. On-Off asymmetry in the perception of blur. Vision Res 2015; 120:5-10. [PMID: 25817715 DOI: 10.1016/j.visres.2015.03.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 03/09/2015] [Accepted: 03/10/2015] [Indexed: 11/18/2022]
Abstract
Natural images appear blurred when imperfect lens focus reduces contrast energy at higher spatial frequencies. Here, we present evidence that perceived blur also depends on asymmetries between On (positive contrast polarities) and Off (negative contrast polarities) image signals. Psychophysical matching experiments involving natural and artificial stimuli suggest that attenuating Off signals at high spatial frequencies results in increased perceptual blur relative to similar attenuations of On signals. Results support the notion that Off image signals play an important role in blur perception.
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Affiliation(s)
- Hiromi Sato
- Department of Psychology, Graduate School of Humanities and Sociology, The University of Tokyo, Japan; JSPS Research Fellow, Japan.
| | | | - Takao Sato
- Department of Psychology, Graduate School of Humanities and Sociology, The University of Tokyo, Japan
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44
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Wool LE, Komban SJ, Kremkow J, Jansen M, Li X, Alonso JM, Zaidi Q. Salience of unique hues and implications for color theory. J Vis 2015; 15:10. [PMID: 25761328 PMCID: PMC4319534 DOI: 10.1167/15.2.10] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 11/17/2014] [Indexed: 11/24/2022] Open
Abstract
The unique hues--blue, green, yellow, red--form the fundamental dimensions of opponent-color theories, are considered universal across languages, and provide useful mental representations for structuring color percepts. However, there is no neural evidence for them from neurophysiology or low-level psychophysics. Tapping a higher prelinguistic perceptual level, we tested whether unique hues are particularly salient in search tasks. We found no advantage for unique hues over their nonunique complementary colors. However, yellowish targets were detected faster, more accurately, and with fewer saccades than their complementary bluish targets (including unique blue), while reddish-greenish pairs were not significantly different in salience. Similarly, local field potentials in primate V1 exhibited larger amplitudes and shorter latencies for yellowish versus bluish stimuli, whereas this effect was weaker for reddish versus greenish stimuli. Consequently, color salience is affected more by early neural response asymmetries than by any possible mental or neural representation of unique hues.
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Affiliation(s)
- Lauren E. Wool
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
| | - Stanley J. Komban
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
| | - Jens Kremkow
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
| | - Michael Jansen
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
| | - Xiaobing Li
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
| | - Jose-Manuel Alonso
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
| | - Qasim Zaidi
- Graduate Center for Vision Research, State University of New York, New York, NY, USA
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45
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Kaliuzhna M, Prsa M, Gale S, Lee SJ, Blanke O. Learning to integrate contradictory multisensory self-motion cue pairings. J Vis 2015; 15:15.1.10. [PMID: 25589294 DOI: 10.1167/15.1.10] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Humans integrate multisensory information to reduce perceptual uncertainty when perceiving the world and self. Integration fails, however, if a common causality is not attributed to the sensory signals, as would occur in conditions of spatiotemporal discrepancies. In the case of passive self-motion, visual and vestibular cues are integrated according to statistical optimality, yet the extent of cue conflicts that do not compromise this optimality is currently underexplored. Here, we investigate whether human subjects can learn to integrate two arbitrary, but co-occurring, visual and vestibular cues of self-motion. Participants made size comparisons between two successive whole-body rotations using only visual, only vestibular, and both modalities together. The vestibular stimulus provided a yaw self-rotation cue, the visual a roll (Experiment 1) or pitch (Experiment 2) rotation cue. Experimentally measured thresholds in the bimodal condition were compared with theoretical predictions derived from the single-cue thresholds. Our results show that human subjects combine and optimally integrate vestibular and visual information, each signaling self-motion around a different rotation axis (yaw vs. roll and yaw vs. pitch). This finding suggests that the experience of two temporally co-occurring but spatially unrelated self-motion cues leads to inferring a common cause for these two initially unrelated sources of information about self-motion. We discuss our results in terms of specific task demands, cross-modal adaptation, and spatial compatibility. The importance of these results for the understanding of bodily illusions is also discussed.
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Affiliation(s)
- Mariia Kaliuzhna
- Center for Neuroprosthetics, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Mario Prsa
- Center for Neuroprosthetics, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Steven Gale
- Center for Neuroprosthetics, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Stella J Lee
- Center for Neuroprosthetics, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Harvard-MIT Division of Health Sciences and Technology, Harvard Medical School, Cambridge, MA, USA
| | - Olaf Blanke
- Center for Neuroprosthetics, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland Department of Neurology, University Hospital, Geneva, Switzerland
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46
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Pietersen ANJ, Cheong SK, Solomon SG, Tailby C, Martin PR. Temporal response properties of koniocellular (blue-on and blue-off) cells in marmoset lateral geniculate nucleus. J Neurophysiol 2014; 112:1421-38. [DOI: 10.1152/jn.00077.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Visual perception requires integrating signals arriving at different times from parallel visual streams. For example, signals carried on the phasic-magnocellular (MC) pathway reach the cerebral cortex pathways some tens of milliseconds before signals traveling on the tonic-parvocellular (PC) pathway. Visual latencies of cells in the koniocellular (KC) pathway have not been specifically studied in simian primates. Here we compared MC and PC cells to “blue-on” (BON) and “blue-off” (BOF) KC cells; these cells carry visual signals originating in short-wavelength-sensitive (S) cones. We made extracellular recordings in the lateral geniculate nucleus (LGN) of anesthetized marmosets. We found that BON visual latencies are 10–20 ms longer than those of PC or MC cells. A small number of recorded BOF cells ( n = 7) had latencies 10–20 ms longer than those of BON cells. Within all cell groups, latencies of foveal receptive fields (<10° eccentricity) were longer (by 3–8 ms) than latencies of peripheral receptive fields (>10°). Latencies of yellow-off inputs to BON cells lagged the blue-on inputs by up to 30 ms, but no differences in visual latency were seen on comparing marmosets expressing dichromatic (“red-green color-blind”) or trichromatic color vision phenotype. We conclude that S-cone signals leaving the LGN on KC pathways are delayed with respect to signals traveling on PC and MC pathways. Cortical circuits serving color vision must therefore integrate across delays in (red-green) chromatic signals carried by PC cells and (blue-yellow) signals carried by KC cells.
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Affiliation(s)
- A. N. J. Pietersen
- Australian Research Council Centre of Excellence for Integrative Brain Function, University of Sydney, Sydney, Australia
- Save Sight Institute, University of Sydney, Sydney, Australia
| | - S. K. Cheong
- Australian Research Council Centre of Excellence for Integrative Brain Function, University of Sydney, Sydney, Australia
- Save Sight Institute, University of Sydney, Sydney, Australia
| | - S. G. Solomon
- School of Medical Sciences, University of Sydney, Sydney, Australia
- Department of Experimental Psychology, University College London, London, United Kingdom; and
| | - C. Tailby
- School of Medical Sciences, University of Sydney, Sydney, Australia
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia
| | - P. R. Martin
- Australian Research Council Centre of Excellence for Integrative Brain Function, University of Sydney, Sydney, Australia
- Save Sight Institute, University of Sydney, Sydney, Australia
- School of Medical Sciences, University of Sydney, Sydney, Australia
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47
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Schütz AC, Lossin F, Gegenfurtner KR. Dynamic integration of information about salience and value for smooth pursuit eye movements. Vision Res 2014; 113:169-78. [PMID: 25175113 DOI: 10.1016/j.visres.2014.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 08/04/2014] [Accepted: 08/11/2014] [Indexed: 11/29/2022]
Abstract
Eye movement behavior can be determined by bottom-up factors like visual salience and by top-down factors like expected value. These different types of signals have to be combined for the control of eye movements. In this study we investigated how smooth pursuit eye movements integrate salience and value information. Observers were asked to track a random-dot kinematogram containing two coherent motion directions. To manipulate salience, the coherence or the density of one of the motion signals was varied. To manipulate value, observers won or lost money in a separate experiment if they were tracking one or the other motion direction. Our results show that pursuit direction was initially determined only by salience. 300-400 ms after target motion onset, pursuit steered towards the rewarded direction and the salience effects disappeared. The time course of this effect depended crucially on the difficulty to segment the two signal directions. These results indicate that salience determines early pursuit responses in the same way as saccades with short latencies. Value information is processed slower and dominates pursuit after several 100 ms.
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Affiliation(s)
- Alexander C Schütz
- Abteilung Allgemeine Psychologie, Justus-Liebig-Universität, Otto-Behaghel-Str. 10F, 35394 Giessen, Germany.
| | - Felix Lossin
- Abteilung Allgemeine Psychologie, Justus-Liebig-Universität, Otto-Behaghel-Str. 10F, 35394 Giessen, Germany
| | - Karl R Gegenfurtner
- Abteilung Allgemeine Psychologie, Justus-Liebig-Universität, Otto-Behaghel-Str. 10F, 35394 Giessen, Germany
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48
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Khakhalin AS, Koren D, Gu J, Xu H, Aizenman CD. Excitation and inhibition in recurrent networks mediate collision avoidance in Xenopus tadpoles. Eur J Neurosci 2014; 40:2948-62. [PMID: 24995793 DOI: 10.1111/ejn.12664] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 04/23/2014] [Accepted: 05/28/2014] [Indexed: 01/24/2023]
Abstract
Information processing in the vertebrate brain is thought to be mediated through distributed neural networks, but it is still unclear how sensory stimuli are encoded and detected by these networks, and what role synaptic inhibition plays in this process. Here we used a collision avoidance behavior in Xenopus tadpoles as a model for stimulus discrimination and recognition. We showed that the visual system of the tadpole is selective for behaviorally relevant looming stimuli, and that the detection of these stimuli first occurs in the optic tectum. By comparing visually guided behavior, optic nerve recordings, excitatory and inhibitory synaptic currents, and the spike output of tectal neurons, we showed that collision detection in the tadpole relies on the emergent properties of distributed recurrent networks within the tectum. We found that synaptic inhibition was temporally correlated with excitation, and did not actively sculpt stimulus selectivity, but rather it regulated the amount of integration between direct inputs from the retina and recurrent inputs from the tectum. Both pharmacological suppression and enhancement of synaptic inhibition disrupted emergent selectivity for looming stimuli. Taken together these findings suggested that, by regulating the amount of network activity, inhibition plays a critical role in maintaining selective sensitivity to behaviorally-relevant visual stimuli.
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Affiliation(s)
- Arseny S Khakhalin
- Department of Neuroscience, Brown University, Box G-LN, Providence, RI, 02912, USA
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49
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Silva AE, Chubb C. The 3-dimensional, 4-channel model of human visual sensitivity to grayscale scrambles. Vision Res 2014; 101:94-107. [PMID: 24932891 DOI: 10.1016/j.visres.2014.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 05/12/2014] [Accepted: 06/02/2014] [Indexed: 11/18/2022]
Abstract
Previous research supports the claim that human vision has three dimensions of sensitivity to grayscale scrambles (textures composed of randomly scrambled mixtures of different grayscales). However, the preattentive mechanisms (called here "field-capture channels") that confer this sensitivity remain obscure. The current experiments sought to characterize the specific field-capture channels that confer this sensitivity using a task in which the participant is required to detect the location of a small patch of one type of grayscale scramble in an extended background of another type. Analysis of the results supports the existence of four field-capture channels: (1) the (previously characterized) "blackshot" channel, sharply tuned to the blackest grayscales; (2) a (previously unknown) "gray-tuned" field-capture channel whose sensitivity is zero for black rising sharply to maximum sensitivity for grayscales slightly darker than mid-gray then decreasing to half-height for brighter grayscales; (3) an "up-ramped" channel whose sensitivity is zero for black, increases linearly with increasing grayscale reaching a maximum near white; (4) a (complementary) "down-ramped" channel whose sensitivity is maximal for black, decreases linearly reaching a minimum near white. The sensitivity functions of field-capture channels (3) and (4) are linearly dependent; thus, these four field-capture channels collectively confer sensitivity to a 3-dimensional space of histogram variations.
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Affiliation(s)
| | - Charles Chubb
- Department of Cognitive Sciences, UC Irvine, Irvine, CA 92697-5100, United States.
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50
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Komban SJ, Kremkow J, Jin J, Wang Y, Lashgari R, Li X, Zaidi Q, Alonso JM. Neuronal and perceptual differences in the temporal processing of darks and lights. Neuron 2014; 82:224-34. [PMID: 24698277 PMCID: PMC3980847 DOI: 10.1016/j.neuron.2014.02.020] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2014] [Indexed: 11/20/2022]
Abstract
Visual information is mediated by two major thalamic pathways that signal light decrements (OFF) and increments (ON) in visual scenes, the OFF pathway being faster than the ON. Here, we demonstrate that this OFF temporal advantage is transferred to visual cortex and has a correlate in human perception. OFF-dominated cortical neurons in cats responded ∼3 ms faster to visual stimuli than ON-dominated cortical neurons, and dark-mediated suppression in ON-dominated neurons peaked ∼14 ms faster than light-mediated suppression in OFF-dominated neurons. Consistent with the neuronal differences, human observers were 6-14 ms faster at detecting darks than lights and better at discriminating dark than light flickers. Neuronal and perceptual differences both vanished if backgrounds were biased toward darks. Our results suggest that the cortical OFF pathway is faster than the ON pathway at increasing and suppressing visual responses, and these differences have parallels in the human visual perception of lights and darks.
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Affiliation(s)
- Stanley Jose Komban
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA
| | - Jens Kremkow
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA
| | - Jianzhong Jin
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA
| | - Yushi Wang
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA
| | - Reza Lashgari
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA; School of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran, Iran
| | - Xiaobing Li
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA
| | - Qasim Zaidi
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA
| | - Jose-Manuel Alonso
- Graduate Center for Vision Research, SUNY College of Optometry, New York, NY, 10036, USA.
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