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Song J, Breitmeyer BG, Brown JM. Further Examination of the Pulsed- and Steady-Pedestal Paradigms under Hypothetical Parvocellular- and Magnocellular-Biased Conditions. Vision (Basel) 2024; 8:28. [PMID: 38804349 PMCID: PMC11130818 DOI: 10.3390/vision8020028] [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: 01/30/2024] [Revised: 04/12/2024] [Accepted: 04/25/2024] [Indexed: 05/29/2024] Open
Abstract
The pulsed- and steady-pedestal paradigms were designed to track increment thresholds (ΔC) as a function of pedestal contrast (C) for the parvocellular (P) and magnocellular (M) systems, respectively. These paradigms produce contrasting results: linear relationships between ΔC and C are observed in the pulsed-pedestal paradigm, indicative of the P system's processing, while the steady-pedestal paradigm reveals nonlinear functions, characteristic of the M system's response. However, we recently found the P model fits better than the M model for both paradigms, using Gabor stimuli biased towards the M or P systems based on their sensitivity to color and spatial frequency. Here, we used two-square pedestals under green vs. red light in the lower-left vs. upper-right visual fields to bias processing towards the M vs. P system, respectively. Based on our previous findings, we predicted the following: (1) steeper ΔC vs. C functions with the pulsed than the steady pedestal due to different task demands; (2) lower ΔCs in the upper-right vs. lower-left quadrant due to its bias towards P-system processing there; (3) no effect of color, since both paradigms track the P-system; and, most importantly (4) contrast gain should not be higher for the steady than for the pulsed pedestal. In general, our predictions were confirmed, replicating our previous findings and providing further evidence questioning the general validity of using the pulsed- and steady-pedestal paradigms to differentiate the P and M systems.
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Affiliation(s)
- Jaeseon Song
- Department of Psychology, University of Georgia, Athens, GA 30602, USA;
| | | | - James M. Brown
- Department of Psychology, University of Georgia, Athens, GA 30602, USA;
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2
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Song J, Breitmeyer BG, Brown JM. Examining Increment thresholds as a function of pedestal contrast under hypothetical parvo- and magnocellular-biased conditions. Atten Percept Psychophys 2024; 86:213-220. [PMID: 38030820 DOI: 10.3758/s13414-023-02819-w] [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] [Accepted: 11/06/2023] [Indexed: 12/01/2023]
Abstract
Theoretically, the pulsed- and steady-pedestal paradigms are thought to track contrast-increment thresholds (ΔC) as a function of pedestal contrast (C) for the parvocellular (P) and magnocellular (M) systems, respectively, yielding linear ΔC versus C functions for the pulsed- and nonlinear functions for the steady-pedestal paradigm. A recent study utilizing these paradigms to isolate the P and M systems reported no evidence of the M system being suppressed by red light, contrary to previous physiological and psychophysical findings. Curious as to why this may have occurred, we examined how ΔC varies with C for the P and M systems using the pulsed- and steady-pedestal paradigms and stimuli biased towards the P or M systems based on their sensitivity to spatial frequency (SF) and color. We found no effect of color and little influence of SF. To explain this lack of color effects, we used a quantitative model of ΔC (as it changes with C) to obtain Csat and contrast-gain values. The contrast-gain values (i) contradicted the hypothesis that the steady-pedestal paradigm tracks the M-system response, and (ii) our obtained Csat values indicated strongly that both pulsed- and steady-pedestal paradigms track primarily the P-system response.
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Affiliation(s)
- Jaeseon Song
- Department of Psychology, University of Georgia, Athens, GA, 30602-3013, USA.
| | - Bruno G Breitmeyer
- Department of Psychology, University of Houston, Houston, TX, 77204-5022, USA
| | - James M Brown
- Department of Psychology, University of Georgia, Athens, GA, 30602-3013, USA
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3
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Archer DR, Alitto HJ, Usrey WM. Stimulus Contrast Affects Spatial Integration in the Lateral Geniculate Nucleus of Macaque Monkeys. J Neurosci 2021; 41:6246-6256. [PMID: 34103362 PMCID: PMC8287990 DOI: 10.1523/jneurosci.2946-20.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 05/30/2021] [Accepted: 06/02/2021] [Indexed: 11/21/2022] Open
Abstract
Gain-control mechanisms adjust neuronal responses to accommodate the wide range of stimulus conditions in the natural environment. Contrast gain control and extraclassical surround suppression are two manifestations of gain control that govern the responses of neurons in the early visual system. Understanding how these two forms of gain control interact has important implications for the detection and discrimination of stimuli across a range of contrast conditions. Here, we report that stimulus contrast affects spatial integration in the lateral geniculate nucleus of alert macaque monkeys (male and female), whereby neurons exhibit a reduction in the strength of extraclassical surround suppression and an expansion in the preferred stimulus size with low-contrast stimuli compared with high-contrast stimuli. Effects were greater for magnocellular neurons than for parvocellular neurons, indicating stream-specific interactions between stimulus contrast and stimulus size. Within the magnocellular pathway, contrast-dependent effects were comparable for ON-center and OFF-center neurons, despite ON neurons having larger receptive fields, less pronounced surround suppression, and more pronounced contrast gain control than OFF neurons. Together, these findings suggest that the parallel streams delivering visual information from retina to primary visual cortex, serve not only to broaden the range of signals delivered to cortex, but also to provide a substrate for differential interactions between stimulus contrast and stimulus size that may serve to improve stimulus detection and stimulus discrimination under pathway-specific lower and higher contrast conditions, respectively.SIGNIFICANCE STATEMENT Stimulus contrast is a salient feature of visual scenes. Here we examine the influence of stimulus contrast on spatial integration in the lateral geniculate nucleus (LGN). Our results demonstrate that increases in contrast generally increase extraclassical suppression and decrease the size of optimal stimuli, indicating a reduction in the extent of visual space from which LGN neurons integrate signals. Differences between magnocellular and parvocellular neurons are noteworthy and further demonstrate that the feedforward parallel pathways to cortex increase the range of information conveyed for downstream cortical processing, a range broadened by diversity in the ON and OFF pathways. These results have important implications for more complex visual processing that underly the detection and discrimination of stimuli under varying natural conditions.
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Affiliation(s)
- Darlene R Archer
- Center for Neuroscience, University of California, Davis, Davis, California 95616
- SUNY College of Optometry, New York, New York 10036
- Center for Neural Science, New York University, New York, New York 10003
| | - Henry J Alitto
- Center for Neuroscience, University of California, Davis, Davis, California 95616
| | - W Martin Usrey
- Center for Neuroscience, University of California, Davis, Davis, California 95616
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4
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Gamal M, Mounier E, Eldawlatly S. On the Extraction of High-Level Visual Features from Lateral Geniculate Nucleus Activity: A Rat Study. Brain Inform 2021. [DOI: 10.1007/978-3-030-86993-9_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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5
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Felgerolle C, Hébert B, Ardourel M, Meyer-Dilhet G, Menuet A, Pinto-Morais K, Bizot JC, Pichon J, Briault S, Perche O. Visual Behavior Impairments as an Aberrant Sensory Processing in the Mouse Model of Fragile X Syndrome. Front Behav Neurosci 2019; 13:228. [PMID: 31680892 PMCID: PMC6797836 DOI: 10.3389/fnbeh.2019.00228] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 09/12/2019] [Indexed: 12/02/2022] Open
Abstract
Fragile X Syndrome (FXS), the most common inherited form of human intellectual disability (ID) associated with autistic-like behaviors, is characterized by dys-sensitivity to sensory stimuli, especially vision. In the absence of Fragile Mental Retardation Protein (FMRP), both retinal and cerebral structures of the visual pathway are impaired, suggesting that perception and integration of visual stimuli are altered. However, behavioral consequences of these defects remain unknown. In this study, we used male Fmr1−/y mice to further define visual disturbances from a behavioral perspective by focusing on three traits characterizing visual modality: perception of depth, contrasts and movements. We performed specific tests (Optomotor Drum, Visual Cliff) to evaluate these visual modalities, their evolution from youth to adulthood, and to assess their involvement in a cognitive task. We show that Fmr1−/y mice exhibit alteration in their visual skills, displaying impaired perspective perception, a drop in their ability to understand a moving contrasted pattern, and a defect in contrasts discrimination. Interestingly, Fmr1−/y phenotypes remain stable over time from adolescence to late adulthood. Besides, we report that color and shape are meaningful for the achievement of a cognitive test involving object recognition. Altogether, these results underline the significance of visual behavior alterations in FXS conditions and relevance of assessing visual skills in neuropsychiatric models before performing behavioral tasks, such as cognitive assessments, that involve visual discrimination.
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Affiliation(s)
- Chloé Felgerolle
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | - Betty Hébert
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | - Maryvonne Ardourel
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | - Géraldine Meyer-Dilhet
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | - Arnaud Menuet
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | - Kimberley Pinto-Morais
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | | | - Jacques Pichon
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France
| | - Sylvain Briault
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France.,Department of Genetics, Regional Hospital, Orléans, France
| | - Olivier Perche
- UMR7355, CNRS, Orléans, France.,Experimental and Molecular Immunology and Neurogenetics, University of Orléans, Orléans, France.,Department of Genetics, Regional Hospital, Orléans, France
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6
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Pregowska A, Casti A, Kaplan E, Wajnryb E, Szczepanski J. Information processing in the LGN: a comparison of neural codes and cell types. BIOLOGICAL CYBERNETICS 2019; 113:453-464. [PMID: 31243531 PMCID: PMC6658673 DOI: 10.1007/s00422-019-00801-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/17/2019] [Indexed: 06/09/2023]
Abstract
To understand how anatomy and physiology allow an organism to perform its function, it is important to know how information that is transmitted by spikes in the brain is received and encoded. A natural question is whether the spike rate alone encodes the information about a stimulus (rate code), or additional information is contained in the temporal pattern of the spikes (temporal code). Here we address this question using data from the cat Lateral Geniculate Nucleus (LGN), which is the visual portion of the thalamus, through which visual information from the retina is communicated to the visual cortex. We analyzed the responses of LGN neurons to spatially homogeneous spots of various sizes with temporally random luminance modulation. We compared the Firing Rate with the Shannon Information Transmission Rate , which quantifies the information contained in the temporal relationships between spikes. We found that the behavior of these two rates can differ quantitatively. This suggests that the energy used for spiking does not translate directly into the information to be transmitted. We also compared Firing Rates with Information Rates for X-ON and X-OFF cells. We found that, for X-ON cells the Firing Rate and Information Rate often behave in a completely different way, while for X-OFF cells these rates are much more highly correlated. Our results suggest that for X-ON cells a more efficient "temporal code" is employed, while for X-OFF cells a straightforward "rate code" is used, which is more reliable and is correlated with energy consumption.
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Affiliation(s)
- Agnieszka Pregowska
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02–106 Warsaw, Poland
| | - Alex Casti
- Department of Mathematics, Gildart-Haase School of Computer Sciences and Engineering, Fairleigh Dickinson University, Teaneck, NY 07666 USA
| | - Ehud Kaplan
- Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- National Institute of Mental Health (NUDZ), Topolova 748, 250 67 Klecany, Czech Republic
- Department of Philosophy of Science, Charles University, Prague, Czech Republic
| | - Eligiusz Wajnryb
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02–106 Warsaw, Poland
| | - Janusz Szczepanski
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02–106 Warsaw, Poland
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7
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The Augmentation of Retinogeniculate Communication during Thalamic Burst Mode. J Neurosci 2019; 39:5697-5710. [PMID: 31109958 DOI: 10.1523/jneurosci.2320-18.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 05/09/2019] [Accepted: 05/10/2019] [Indexed: 11/21/2022] Open
Abstract
Retinal signals are transmitted to cortex via neurons in the lateral geniculate nucleus (LGN), where they are processed in burst or tonic response mode. Burst mode occurs when LGN neurons are sufficiently hyperpolarized for T-type Ca2+ channels to deinactivate, allowing them to open in response to depolarization, which can trigger a high-frequency sequence of Na+-based spikes (i.e., burst). In contrast, T-type channels are inactivated during tonic mode and do not contribute to spiking. Although burst mode is commonly associated with sleep and the disruption of retinogeniculate communication, bursts can also be triggered by visual stimulation, thereby transforming the retinal signals relayed to the cortex. To determine how burst mode affects retinogeniculate communication, we made recordings from monosynaptically connected retinal ganglion cells and LGN neurons in male/female cats during visual stimulation. Our results reveal a robust augmentation of retinal signals within the LGN during burst mode. Specifically, retinal spikes were more effective and often triggered multiple LGN spikes during periods likely to have increased T-type Ca2+ channel activity. Consistent with the biophysical properties of T-type Ca2+ channels, analysis revealed that effect magnitude was correlated with the duration of the preceding thalamic interspike interval and occurred even in the absence of classically defined bursts. Importantly, the augmentation of geniculate responses to retinal input was not associated with a degradation of visual signals. Together, these results indicate a graded nature of response mode and suggest that, under certain conditions, bursts facilitate the transmission of visual information to the cortex by amplifying retinal signals.SIGNIFICANCE STATEMENT The thalamus is the gateway for retinal information traveling to the cortex. The lateral geniculate nucleus, like all thalamic nuclei, has two classically defined categories of spikes-tonic and burst-that differ in their underlying cellular mechanisms. Here we compare retinogeniculate communication during burst and tonic response modes. Our results show that retinogeniculate communication is enhanced during burst mode and visually evoked thalamic bursts, thereby augmenting retinal signals transmitted to cortex. Further, our results demonstrate that the influence of burst mode on retinogeniculate communication is graded and can be measured even in the absence of classically defined thalamic bursts.
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8
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Román Rosón M, Bauer Y, Kotkat AH, Berens P, Euler T, Busse L. Mouse dLGN Receives Functional Input from a Diverse Population of Retinal Ganglion Cells with Limited Convergence. Neuron 2019; 102:462-476.e8. [PMID: 30799020 DOI: 10.1016/j.neuron.2019.01.040] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 11/08/2018] [Accepted: 01/17/2019] [Indexed: 10/27/2022]
Abstract
Mouse vision is based on the parallel output of more than 30 functional types of retinal ganglion cells (RGCs). Little is known about how representations of visual information change between retina and dorsolateral geniculate nucleus (dLGN) of the thalamus, the main relay between retina and cortex. Here, we functionally characterized responses of retrogradely labeled dLGN-projecting RGCs and dLGN neurons to the same set of visual stimuli. We found that many of the previously identified functional RGC types innervate dLGN, which maintained a high degree of functional diversity. Using a linear model to assess functional connectivity between RGC types and dLGN neurons, we found that responses of dLGN neurons could be predicted as linear combination of inputs from on average five RGC types, but only two of those had the strongest functional impact. Thus, mouse dLGN receives functional input from a diverse population of RGC types with limited convergence.
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Affiliation(s)
- Miroslav Román Rosón
- Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Institute for Ophthalmic Research, University Hospital Tübingen, 72076 Tübingen, Germany; Division of Neurobiology, Department Biology II, LMU Munich, 82151 Munich, Germany; Graduate School of Neural & Behavioural Sciences, International Max Planck Research School, University of Tübingen, 72074 Tübingen, Germany
| | - Yannik Bauer
- Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Division of Neurobiology, Department Biology II, LMU Munich, 82151 Munich, Germany; Graduate School of Systemic Neuroscience (GSN), LMU Munich, 82151 Munich, Germany
| | - Ann H Kotkat
- Division of Neurobiology, Department Biology II, LMU Munich, 82151 Munich, Germany; ENB Elite Master of Science Program in Neuroengineering, Technical University of Munich, 80333 Munich, Germany
| | - Philipp Berens
- Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Institute for Ophthalmic Research, University Hospital Tübingen, 72076 Tübingen, Germany; Bernstein Centre for Computational Neuroscience, 72076 Tübingen, Germany.
| | - Thomas Euler
- Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Institute for Ophthalmic Research, University Hospital Tübingen, 72076 Tübingen, Germany; Bernstein Centre for Computational Neuroscience, 72076 Tübingen, Germany.
| | - Laura Busse
- Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Division of Neurobiology, Department Biology II, LMU Munich, 82151 Munich, Germany; Bernstein Centre for Computational Neuroscience, 72076 Tübingen, Germany; Bernstein Centre for Computational Neuroscience, 82151 Munich, Germany.
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9
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Lempel AA, Nielsen KJ. Ferrets as a Model for Higher-Level Visual Motion Processing. Curr Biol 2018; 29:179-191.e5. [PMID: 30595516 DOI: 10.1016/j.cub.2018.11.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/03/2018] [Accepted: 11/05/2018] [Indexed: 10/27/2022]
Abstract
Ferrets are a major developmental animal model due to their early parturition. Here we show for the first time that ferrets could be used to study development of higher-level visual processes previously identified in primates. In primates, complex motion processing involves primary visual cortex (V1), which generates local motion signals, and higher-level visual area MT, which integrates these signals over more global spatial regions. Our data show similar transformations in motion signals between ferret V1 and higher-level visual area PSS, located in the posterior bank of the suprasylvian sulcus. We found that PSS neurons, like MT neurons, were tuned for stimulus motion and showed strong suppression between opposing direction inputs. Most strikingly, PSS, like MT, exhibited robust global motion signals when tested with coherent plaids-the classic test for motion integration across multiple moving elements. These PSS responses were described well by computational models developed for MT. Our findings establish the ferret as a strong animal model for development of higher-level visual processing.
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Affiliation(s)
- Augusto A Lempel
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Kristina J Nielsen
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD 21218, USA.
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10
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Liang L, Fratzl A, Goldey G, Ramesh RN, Sugden AU, Morgan JL, Chen C, Andermann ML. A Fine-Scale Functional Logic to Convergence from Retina to Thalamus. Cell 2018; 173:1343-1355.e24. [PMID: 29856953 DOI: 10.1016/j.cell.2018.04.041] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 01/31/2018] [Accepted: 04/27/2018] [Indexed: 11/26/2022]
Abstract
Numerous well-defined classes of retinal ganglion cells innervate the thalamus to guide image-forming vision, yet the rules governing their convergence and divergence remain unknown. Using two-photon calcium imaging in awake mouse thalamus, we observed a functional arrangement of retinal ganglion cell axonal boutons in which coarse-scale retinotopic ordering gives way to fine-scale organization based on shared preferences for other visual features. Specifically, at the ∼6 μm scale, clusters of boutons from different axons often showed similar preferences for either one or multiple features, including axis and direction of motion, spatial frequency, and changes in luminance. Conversely, individual axons could "de-multiplex" information channels by participating in multiple, functionally distinct bouton clusters. Finally, ultrastructural analyses demonstrated that retinal axonal boutons in a local cluster often target the same dendritic domain. These data suggest that functionally specific convergence and divergence of retinal axons may impart diverse, robust, and often novel feature selectivity to visual thalamus.
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Affiliation(s)
- Liang Liang
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Alex Fratzl
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Laboratory of Synaptic Mechanisms, Brain Mind Institute, School of Life Science, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Glenn Goldey
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Rohan N Ramesh
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
| | - Arthur U Sugden
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Josh L Morgan
- Department of Ophthalmology and Visual Sciences, Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chinfei Chen
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA.
| | - Mark L Andermann
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA.
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11
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Alitto HJ, Rathbun DL, Fisher TG, Alexander PC, Usrey WM. Contrast gain control and retinogeniculate communication. Eur J Neurosci 2018. [PMID: 29520859 DOI: 10.1111/ejn.13904] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Visual information processed in the retina is transmitted to primary visual cortex via relay cells in the lateral geniculate nucleus (LGN) of the dorsal thalamus. Although retinal ganglion cells are the primary source of driving input to LGN neurons, not all retinal spikes are transmitted to the cortex. Here, we investigate the relationship between stimulus contrast and retinogeniculate communication and test the hypothesis that both the time course and strength of retinogeniculate interactions are dynamic and dependent on stimulus contrast. By simultaneously recording the spiking activity of synaptically connected retinal ganglion cells and LGN neurons in the cat, we show that the temporal window for retinogeniculate integration and the effectiveness of individual retinal spikes are inversely proportional to stimulus contrast. This finding provides a mechanistic understanding for the phenomenon of augmented contrast gain control in the LGN-a nonlinear receptive field property of LGN neurons whereby response gain during low-contrast stimulation is enhanced relative to response gain during high-contrast stimulation. In addition, these results support the view that network interactions beyond the retina play an essential role in transforming visual signals en route from retina to cortex.
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Affiliation(s)
- Henry J Alitto
- Center for Neuroscience, University of California, 1544 Newton Court, Davis, CA, 95618, USA.,Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, USA
| | - Daniel L Rathbun
- Center for Neuroscience, University of California, 1544 Newton Court, Davis, CA, 95618, USA.,Institute for Ophthalmology and Center for Integrative Neuroscience, University of Tuebingen, D-72076, Tuebingen, Germany
| | - Tucker G Fisher
- Center for Neuroscience, University of California, 1544 Newton Court, Davis, CA, 95618, USA.,Department of Neurobiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Prescott C Alexander
- Center for Neuroscience, University of California, 1544 Newton Court, Davis, CA, 95618, USA.,Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, USA
| | - W Martin Usrey
- Center for Neuroscience, University of California, 1544 Newton Court, Davis, CA, 95618, USA.,Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, USA
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12
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Monavarfeshani A, Stanton G, Van Name J, Su K, Mills WA, Swilling K, Kerr A, Huebschman NA, Su J, Fox MA. LRRTM1 underlies synaptic convergence in visual thalamus. eLife 2018; 7:e33498. [PMID: 29424692 PMCID: PMC5826289 DOI: 10.7554/elife.33498] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 02/08/2018] [Indexed: 11/13/2022] Open
Abstract
It has long been thought that the mammalian visual system is organized into parallel pathways, with incoming visual signals being parsed in the retina based on feature (e.g. color, contrast and motion) and then transmitted to the brain in unmixed, feature-specific channels. To faithfully convey feature-specific information from retina to cortex, thalamic relay cells must receive inputs from only a small number of functionally similar retinal ganglion cells. However, recent studies challenged this by revealing substantial levels of retinal convergence onto relay cells. Here, we sought to identify mechanisms responsible for the assembly of such convergence. Using an unbiased transcriptomics approach and targeted mutant mice, we discovered a critical role for the synaptic adhesion molecule Leucine Rich Repeat Transmembrane Neuronal 1 (LRRTM1) in the emergence of retinothalamic convergence. Importantly, LRRTM1 mutant mice display impairment in visual behaviors, suggesting a functional role of retinothalamic convergence in vision.
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Affiliation(s)
- Aboozar Monavarfeshani
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
- Department of Biological SciencesVirginia TechBlacksburgUnited States
| | - Gail Stanton
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
- Virginia Tech Carilion School of MedicineRoanokeUnited States
| | - Jonathan Van Name
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
| | - Kaiwen Su
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
| | - William A Mills
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
- Translational Biology, Medicine, and Health Graduate ProgramVirginia TechBlacksburgUnited States
| | - Kenya Swilling
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
| | - Alicia Kerr
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
- Translational Biology, Medicine, and Health Graduate ProgramVirginia TechBlacksburgUnited States
| | | | - Jianmin Su
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
| | - Michael A Fox
- Developmental and Translational Neurobiology CenterVirginia Tech Carilion Research InstituteRoanokeUnited States
- Department of Biological SciencesVirginia TechBlacksburgUnited States
- Virginia Tech Carilion School of MedicineRoanokeUnited States
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Litvina EY, Chen C. Functional Convergence at the Retinogeniculate Synapse. Neuron 2017; 96:330-338.e5. [PMID: 29024658 DOI: 10.1016/j.neuron.2017.09.037] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/01/2017] [Accepted: 09/22/2017] [Indexed: 01/03/2023]
Abstract
Precise connectivity between retinal ganglion cells (RGCs) and thalamocortical (TC) relay neurons is thought to be essential for the transmission of visual information. Consistent with this view, electrophysiological measurements have previously estimated that 1-3 RGCs converge onto a mouse geniculate TC neuron. Recent advances in connectomics and rabies tracing have yielded much higher estimates of retinogeniculate convergence, although not all identified contacts may be functional. Here we use optogenetics and a computational simulation to determine the number of functionally relevant retinogeniculate inputs onto TC neurons in mice. We find an average of ten RGCs converging onto a mature TC neuron, in contrast to >30 inputs before developmental refinement. However, only 30% of retinogeniculate inputs exceed the threshold for dominating postsynaptic activity. These results signify a greater role for the thalamus in visual processing and provide a functional perspective of anatomical connectivity data.
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Affiliation(s)
- Elizabeth Y Litvina
- Department of Neurology, F.M. Kirby Neurobiology Center, Children's Hospital, Boston, 300 Longwood Avenue, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Chinfei Chen
- Department of Neurology, F.M. Kirby Neurobiology Center, Children's Hospital, Boston, 300 Longwood Avenue, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
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Retinal and Nonretinal Contributions to Extraclassical Surround Suppression in the Lateral Geniculate Nucleus. J Neurosci 2017; 37:226-235. [PMID: 28053044 DOI: 10.1523/jneurosci.1577-16.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 10/24/2016] [Accepted: 11/17/2016] [Indexed: 02/07/2023] Open
Abstract
Extraclassical surround suppression is a prominent receptive field property of neurons in the lateral geniculate nucleus (LGN) of the dorsal thalamus, influencing stimulus size tuning, response gain control, and temporal features of visual responses. Despite evidence for the involvement of both retinal and nonretinal circuits in the generation of extraclassical suppression, we lack an understanding of the relative roles played by these pathways and how they interact during visual stimulation. To determine the contribution of retinal and nonretinal mechanisms to extraclassical suppression in the feline, we made simultaneous single-unit recordings from synaptically connected retinal ganglion cells and LGN neurons and measured the influence of stimulus size on the spiking activity of presynaptic and postsynaptic neurons. Results show that extraclassical suppression is significantly stronger for LGN neurons than for their retinal inputs, indicating a role for extraretinal mechanisms. Further analysis revealed that the enhanced suppression can be accounted for by mechanisms that suppress the effectiveness of retinal inputs in evoking LGN spikes. Finally, an examination of the time course for the onset of extraclassical suppression in the LGN and the size-dependent modulation of retinal spike efficacy suggests the early phase of augmented suppression involves local thalamic circuits. Together, these results demonstrate that the LGN is much more than a simple relay for retinal signals to cortex; it also filters retinal spikes dynamically on the basis of stimulus statistics to adjust the gain of visual signals delivered to cortex. SIGNIFICANCE STATEMENT The lateral geniculate nucleus (LGN) is the gateway through which retinal information reaches the cerebral cortex. Within the LGN, neuronal responses are often suppressed by stimuli that extend beyond the classical receptive field. This form of suppression, called extraclassical suppression, serves to adjust the size tuning, response gain, and temporal response properties of neurons. Given the important influence of extraclassical suppression on visual signals delivered to cortex, we performed experiments to determine the circuit mechanisms that contribute to extraclassical suppression in the LGN. Results show that suppression is augmented beyond that provided by direct retinal inputs and delayed, consistent with polysynaptic inhibition. Importantly, these mechanisms influence the effectiveness of incoming retinal signals, thereby filtering the signals ultimately conveyed to cortex.
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Abstract
The thalamocortical (TC) relay neuron of the dorsoLateral Geniculate Nucleus (dLGN) has borne its imprecise label for many decades in spite of strong evidence that its role in visual processing transcends the implied simplicity of the term "relay". The retinogeniculate synapse is the site of communication between a retinal ganglion cell and a TC neuron of the dLGN. Activation of retinal fibers in the optic tract causes reliable, rapid, and robust postsynaptic potentials that drive postsynaptics spikes in a TC neuron. Cortical and subcortical modulatory systems have been known for decades to regulate retinogeniculate transmission. The dynamic properties that the retinogeniculate synapse itself exhibits during and after developmental refinement further enrich the role of the dLGN in the transmission of the retinal signal. Here we consider the structural and functional substrates for retinogeniculate synaptic transmission and plasticity, and reflect on how the complexity of the retinogeniculate synapse imparts a novel dynamic and influential capacity to subcortical processing of visual information.
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Affiliation(s)
- Elizabeth Y Litvina
- Department of Neurology,F.M. Kirby Neurobiology Center,Children's Hospital, Boston,Boston,Massachusetts 02115
| | - Chinfei Chen
- Department of Neurology,F.M. Kirby Neurobiology Center,Children's Hospital, Boston,Boston,Massachusetts 02115
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