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Su C, Mendes-Platt RF, Alonso JM, Swadlow HA, Bereshpolova Y. Retinal direction of motion is reliably transmitted to visual cortex through highly selective thalamocortical connections. Curr Biol 2024:S0960-9822(24)01520-3. [PMID: 39644892 DOI: 10.1016/j.cub.2024.11.013] [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: 06/04/2024] [Revised: 09/27/2024] [Accepted: 11/07/2024] [Indexed: 12/09/2024]
Abstract
Motion perception is crucial to animal survival and effective environmental interactions. In mammals, detection of movement begins in the retina. Directionally selective (DS) retinal ganglion cells were first discovered in the rabbit eye,1 and they have since been found in mouse,2,3 cat,4 and monkey.5,6 These DS retinal neurons contact a small population of neurons in the visual thalamus (dorsal lateral geniculate nucleus [LGN]) that are highly DS.7,8,9,10 The primary visual cortex (V1) also contains DS neurons, but whether directional selectivity in V1 emerges de novo11,12,13 or is inherited from DS thalamic inputs14,15,16 remains unclear. We previously found that LGN-DS neurons generate strong and focal synaptic currents in rabbit V1, similar to those generated by LGN concentric cells.17 Thus, the synaptic drive generated by LGN-DS neurons in V1 is spatially well situated to influence the firing of layer 4 (L4) simple cells, most of which show strong directional selectivity.18 However, two important questions remain: do LGN-DS neurons synaptically target DS simple cells in L4, and, if so, do they contribute to the directional preferences of these V1 DS neurons? We used spike-train cross-correlation analysis of pairs of LGN-DS and L4 simple cells to address these questions. We found that LGN-DS neurons do target L4 DS simple cells and that the targeting is highly selective, largely following a simple set of "connectivity rules." We conclude that this highly selective thalamocortical connectivity of LGN-DS neurons contributes to the sharp directional selectivity of cortical simple cells.
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Affiliation(s)
- Chuyi Su
- Deptartment of Psychological Sciences, University of Connecticut, Storrs, CT 06269, USA
| | | | - Jose-Manuel Alonso
- Deptartment of Psychological Sciences, University of Connecticut, Storrs, CT 06269, USA; Deptartment of Biological and Vision Sciences, SUNY-Optometry, New York, NY 10036, USA
| | - Harvey A Swadlow
- Deptartment of Psychological Sciences, University of Connecticut, Storrs, CT 06269, USA; Deptartment of Biological and Vision Sciences, SUNY-Optometry, New York, NY 10036, USA
| | - Yulia Bereshpolova
- Deptartment of Psychological Sciences, University of Connecticut, Storrs, CT 06269, USA.
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2
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Sun SH, Killian NJ, Pezaris JS. More than expected: extracellular waveforms and functional responses in monkey LGN. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.22.568065. [PMID: 38798485 PMCID: PMC11118448 DOI: 10.1101/2023.11.22.568065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Unlike the exhaustive determination of cell types in the retina, key populations in the lateral geniculate nucleus of the thalamus (LGN) may have been missed. Here, we have begun to characterize the full range of extracellular neuronal responses in the LGN of awake monkeys using multi-electrodes during the presentation of colored noise visual stimuli to identify any previously overlooked signals. Extracellular spike waveforms of single units were classified into seven distinct classes, revealing previously unrecognized diversity: four negative-dominant classes that were narrow or broad, one triphasic class, and two positive-dominant classes. Based on their mapped receptive field (RF), these units were further categorized into either magnocellular (M), parvocellular (P), koniocellular (K), or non-RF (N). We found correlations between spike shape and mapped RF and response characteristics, with negative and narrow spiking waveform units predominantly associated with P and N RFs, and positive waveforms mostly linked to M RFs. Responses from positive waveforms exhibited shorter latencies, larger RF sizes, and were associated with larger eccentricities in the visual field than the other waveform classes. Additionally, N cells, those without an estimated RF, were consistently responsive to the visually presented mapping stimulus at a lower and more sustained rate than units with an RF. These findings suggest that the LGN cell population may be more diverse than previously believed.
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Affiliation(s)
- Shi Hai Sun
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA, USA
- Department of Neurosurgery, Harvard Medical School, Boston, MA, USA
| | - Nathaniel J Killian
- Department of Neurological Surgery, Albert Einstein College of Medicine, Bronx, NY, USA
| | - John S Pezaris
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA, USA
- Department of Neurosurgery, Harvard Medical School, Boston, MA, USA
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Rai BB, Sabeti F, Carle CF, Maddess T. Visual Field Tests: A Narrative Review of Different Perimetric Methods. J Clin Med 2024; 13:2458. [PMID: 38730989 PMCID: PMC11084906 DOI: 10.3390/jcm13092458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/11/2024] [Accepted: 04/16/2024] [Indexed: 05/13/2024] Open
Abstract
Visual field (VF) testing dates back to fifth century B.C. It plays a pivotal role in the diagnosis, management, and prognosis of retinal and neurological diseases. This review summarizes each of the different VF tests and perimetric methods, including the advantages and disadvantages and adherence to the desired standard diagnostic criteria. The review targets beginners and eye care professionals and includes history and evolution, qualitative and quantitative tests, and subjective and objective perimetric methods. VF testing methods have evolved in terms of technique, precision, user-friendliness, and accuracy. Consequently, some earlier perimetric techniques, often still effective, are not used or have been forgotten. Newer technologies may not always be advantageous because of higher costs, and they may not achieve the desired sensitivity and specificity. VF testing is most often used in glaucoma and neurological diseases, but new objective methods that also measure response latencies are emerging for the management of retinal diseases. Given the varied perimetric methods available, clinicians are advised to select appropriate methods to suit their needs and target disease and to decide on applying simple vs. complex tests or between using subjective and objective methods. Newer, rapid, non-contact, objective methods may provide improved patient satisfaction and allow for the testing of children and the infirm.
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Affiliation(s)
- Bhim Bahadur Rai
- John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia; (F.S.); (C.F.C.); (T.M.)
| | - Faran Sabeti
- John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia; (F.S.); (C.F.C.); (T.M.)
- Faculty of Health, School of Optometry, University of Canberra, Canberra, ACT 2601, Australia
| | - Corinne Frances Carle
- John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia; (F.S.); (C.F.C.); (T.M.)
| | - Ted Maddess
- John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia; (F.S.); (C.F.C.); (T.M.)
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Lempel AA, Fitzpatrick D. Developmental alignment of feedforward inputs and recurrent network activity drives increased response selectivity and reliability in primary visual cortex following the onset of visual experience. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.09.547747. [PMID: 37503207 PMCID: PMC10369900 DOI: 10.1101/2023.07.09.547747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Selective and reliable cortical sensory representations depend on synaptic interactions between feedforward inputs, conveying information from lower levels of the sensory pathway, and recurrent networks that reciprocally connect neurons functioning at the same hierarchical level. Here we explore the development of feedforward/recurrent interactions in primary visual cortex of the ferret that is responsible for the representation of orientation, focusing on the feedforward inputs from cortical layer 4 and its relation to the modular recurrent network in layer 2/3 before and after the onset of visual experience. Using simultaneous laminar electrophysiology and calcium imaging we found that in experienced animals, individual layer 4 and layer 2/3 neurons exhibit strongly correlated responses with the modular recurrent network structure in layer 2/3. Prior to experience, layer 2/3 neurons exhibit comparable modular correlation structure, but this correlation structure is missing for individual layer 4 neurons. Further analysis of the receptive field properties of layer 4 neurons in naïve animals revealed that they exhibit very poor orientation tuning compared to layer 2/3 neurons at this age, and this is accompanied by the lack of spatial segregation of ON and OFF subfields, the definitive property of layer 4 simple cells in experienced animals. Analysis of the response dynamics of layer 2/3 neurons with whole-cell patch recordings confirms that individual layer 2/3 neurons in naïve animals receive poorly-selective feedforward input that does not align with the orientation preference of the layer 2/3 responses. Further analysis reveals that the misaligned feedforward input is the underlying cause of reduced selectivity and increased response variability that is evident in the layer 2/3 responses of naïve animals. Altogether, our experiments indicate that the onset of visual experience is accompanied by a critical refinement in the responses of layer 4 neurons and the alignment of feedforward and recurrent networks that increases the selectivity and reliability of the representation of orientation in V1.
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Silson EH, Baker CI, Aleman TS, Maguire AM, Bennett J, Ashtari M. Motion-selective areas V5/MT and MST appear resistant to deterioration in choroideremia. Neuroimage Clin 2023; 38:103384. [PMID: 37023490 PMCID: PMC10119684 DOI: 10.1016/j.nicl.2023.103384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 03/07/2023] [Accepted: 03/20/2023] [Indexed: 04/08/2023]
Abstract
Choroideremia (CHM) is an X-linked recessive form of hereditary retinal degeneration, which preserves only small islands of central retinal tissue. Previously, we demonstrated the relationship between central vision and structure and population receptive fields (pRF) using functional magnetic resonance imaging (fMRI) in untreated CHM subjects. Here, we replicate and extend this work, providing a more in-depth analysis of the visual responses in a cohort of CHM subjects who participated in a retinal gene therapy clinical trial. fMRI was conducted in six CHM subjects and six age-matched healthy controls (HC's) while they viewed drifting contrast pattern stimuli monocularly. A single ∼3-minute fMRI run was collected for each eye. Participants also underwent ophthalmic evaluations of visual acuity and static automatic perimetry (SAP). Consistent with our previous report, a single ∼ 3 min fMRI run accurately characterized ophthalmic evaluations of visual function in most CHM subjects. In-depth analyses of the cortical distribution of pRF responses revealed that the motion-selective regions V5/MT and MST appear resistant to progressive retinal degenerations in CHM subjects. This effect was restricted to V5/MT and MST and was not present in either primary visual cortex (V1), motion-selective V3A or regions within the ventral visual pathway. Motion-selective areas V5/MT and MST appear to be resistant to the continuous detrimental impact of CHM. Such resilience appears selective to these areas and may be mediated by independent retina-V5/MT anatomical connections that bypass V1. We did not observe any significant impact of gene therapy.
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Affiliation(s)
- Edward H Silson
- Section on Learning and Plasticity, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Chris I Baker
- Section on Learning and Plasticity, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Tomas S Aleman
- Center for Advanced Retinal and Ocular Therapeutics (CAROT), University of Pennsylvania, Philadelphia, PA, United States; F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Albert M Maguire
- Center for Advanced Retinal and Ocular Therapeutics (CAROT), University of Pennsylvania, Philadelphia, PA, United States; F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Jean Bennett
- Center for Advanced Retinal and Ocular Therapeutics (CAROT), University of Pennsylvania, Philadelphia, PA, United States; F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Manzar Ashtari
- Center for Advanced Retinal and Ocular Therapeutics (CAROT), University of Pennsylvania, Philadelphia, PA, United States; F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States; Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States.
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6
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EMERY KARAJ, ISHERWOOD ZOEYJ, WEBSTER MICHAELA. Gaining the system: limits to compensating color deficiencies through post-receptoral gain changes. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2023; 40:A16-A25. [PMID: 37132998 PMCID: PMC10157001 DOI: 10.1364/josaa.480035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/14/2022] [Indexed: 05/04/2023]
Abstract
Color percepts of anomalous trichromats are often more similar to normal trichromats than predicted from their receptor spectral sensitivities, suggesting that post-receptoral mechanisms can compensate for chromatic losses. The basis for these adjustments and the extent to which they could discount the deficiency are poorly understood. We modeled the patterns of compensation that might result from increasing the gains in post-receptoral neurons to offset their weakened inputs. Individual neurons and the population responses jointly encode luminance and chromatic signals. As a result, they cannot independently adjust for a change in the chromatic inputs, predicting only partial recovery of the chromatic responses and increased responses to achromatic contrast. These analyses constrain the potential sites and mechanisms of compensation for a color loss and characterize the utility and limits of neural gain changes for calibrating color vision.
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Affiliation(s)
- KARA J. EMERY
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, Reno NV 89557
- Center for Data Science, New York University, New York NY 10011
| | - ZOEY J. ISHERWOOD
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, Reno NV 89557
| | - MICHAEL A. WEBSTER
- Department of Psychology and Graduate Program in Integrative Neuroscience, University of Nevada, Reno, Reno NV 89557
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Santana NNM, Silva EHA, dos Santos SF, Costa MSMO, Nascimento Junior ES, Engelberth RCJG, Cavalcante JS. Retinorecipient areas in the common marmoset ( Callithrix jacchus): An image-forming and non-image forming circuitry. Front Neural Circuits 2023; 17:1088686. [PMID: 36817647 PMCID: PMC9932520 DOI: 10.3389/fncir.2023.1088686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 01/10/2023] [Indexed: 02/05/2023] Open
Abstract
The mammalian retina captures a multitude of diverse features from the external environment and conveys them via the optic nerve to a myriad of retinorecipient nuclei. Understanding how retinal signals act in distinct brain functions is one of the most central and established goals of neuroscience. Using the common marmoset (Callithrix jacchus), a monkey from Northeastern Brazil, as an animal model for parsing how retinal innervation works in the brain, started decades ago due to their marmoset's small bodies, rapid reproduction rate, and brain features. In the course of that research, a large amount of new and sophisticated neuroanatomical techniques was developed and employed to explain retinal connectivity. As a consequence, image and non-image-forming regions, functions, and pathways, as well as retinal cell types were described. Image-forming circuits give rise directly to vision, while the non-image-forming territories support circadian physiological processes, although part of their functional significance is uncertain. Here, we reviewed the current state of knowledge concerning retinal circuitry in marmosets from neuroanatomical investigations. We have also highlighted the aspects of marmoset retinal circuitry that remain obscure, in addition, to identify what further research is needed to better understand the connections and functions of retinorecipient structures.
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Affiliation(s)
- Nelyane Nayara M. Santana
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Eryck H. A. Silva
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Sâmarah F. dos Santos
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Miriam S. M. O. Costa
- Laboratory of Neuroanatomy, Department of Morphology, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Expedito S. Nascimento Junior
- Laboratory of Neuroanatomy, Department of Morphology, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Rovena Clara J. G. Engelberth
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Jeferson S. Cavalcante
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Bioscience Center, Federal University of Rio Grande do Norte, Natal, Brazil,*Correspondence: Jeferson S. Cavalcante,
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8
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Baldicano AK, Nasir-Ahmad S, Novelli M, Lee SCS, Do MTH, Martin PR, Grünert U. Retinal ganglion cells expressing CaM kinase II in human and nonhuman primates. J Comp Neurol 2022; 530:1470-1493. [PMID: 35029299 PMCID: PMC9010361 DOI: 10.1002/cne.25292] [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: 11/30/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 11/07/2022]
Abstract
Immunoreactivity for calcium-/calmodulin-dependent protein kinase II (CaMKII) in the primate dorsal lateral geniculate nucleus (dLGN) has been attributed to geniculocortical relay neurons and has also been suggested to arise from terminals of retinal ganglion cells. Here, we combined immunostaining with single-cell injections to investigate the expression of CaMKII in retinal ganglion cells of three primate species: macaque (Macaca fascicularis, M. nemestrina), human, and marmoset (Callithrix jacchus). We found that in all species, about 2%-10% of the total ganglion cell population expressed CaMKII. In all species, CaMKII was expressed by multiple types of wide-field ganglion cell including large sparse, giant sparse (melanopsin-expressing), broad thorny, and narrow thorny cells. Three other ganglion cells types, namely, inner and outer stratifying maze cells in macaque and tufted cells in marmoset were also found. Double labeling experiments showed that CaMKII-expressing cells included inner and outer stratifying melanopsin cells. Nearly all CaMKII-expressing ganglion cell types identified here are known to project to the koniocellular layers of the dLGN as well as to the superior colliculus. The best characterized koniocellular projecting cell type-the small bistratified (blue ON/yellow OFF) cell-was, however, not CaMKII-positive in any species. Our results indicate that the pattern of CaMKII expression in retinal ganglion cells is largely conserved across different species of primate suggesting a common functional role. But the results also show that CaMKII is not a marker for all koniocellular projecting retinal ganglion cells.
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Affiliation(s)
- Alyssa K Baldicano
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Subha Nasir-Ahmad
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, NSW, 2000, Australia
| | - Mario Novelli
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Sammy C S Lee
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, NSW, 2000, Australia
| | - Michael Tri H Do
- F.M. Kirby Neurobiology Center and Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Paul R Martin
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, NSW, 2000, Australia
| | - Ulrike Grünert
- Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Australian Research Council Centre of Excellence for Integrative Brain Function, The University of Sydney, Sydney, NSW, 2000, Australia
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Kaas JH, Qi HX, Stepniewska I. Escaping the nocturnal bottleneck, and the evolution of the dorsal and ventral streams of visual processing in primates. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210293. [PMID: 34957843 PMCID: PMC8710890 DOI: 10.1098/rstb.2021.0293] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/21/2021] [Indexed: 12/12/2022] Open
Abstract
Early mammals were small and nocturnal. Their visual systems had regressed and they had poor vision. After the extinction of the dinosaurs 66 mya, some but not all escaped the 'nocturnal bottleneck' by recovering high-acuity vision. By contrast, early primates escaped the bottleneck within the age of dinosaurs by having large forward-facing eyes and acute vision while remaining nocturnal. We propose that these primates differed from other mammals by changing the balance between two sources of visual information to cortex. Thus, cortical processing became less dependent on a relay of information from the superior colliculus (SC) to temporal cortex and more dependent on information distributed from primary visual cortex (V1). In addition, the two major classes of visual information from the retina became highly segregated into magnocellular (M cell) projections from V1 to the primate-specific temporal visual area (MT), and parvocellular-dominated projections to the dorsolateral visual area (DL or V4). The greatly expanded P cell inputs from V1 informed the ventral stream of cortical processing involving temporal and frontal cortex. The M cell pathways from V1 and the SC informed the dorsal stream of cortical processing involving MT, surrounding temporal cortex, and parietal-frontal sensorimotor domains. This article is part of the theme issue 'Systems neuroscience through the lens of evolutionary theory'.
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Affiliation(s)
- Jon H. Kaas
- Department of Pshycology, Vanderbilt University, 301 Wilson Hall, 111 21st Ave. S., Nashville, TN 37240, USA
| | - Hui-Xin Qi
- Department of Pshycology, Vanderbilt University, 301 Wilson Hall, 111 21st Ave. S., Nashville, TN 37240, USA
| | - Iwona Stepniewska
- Department of Pshycology, Vanderbilt University, 301 Wilson Hall, 111 21st Ave. S., Nashville, TN 37240, USA
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Ichinose T, Habib S. ON and OFF Signaling Pathways in the Retina and the Visual System. FRONTIERS IN OPHTHALMOLOGY 2022; 2:989002. [PMID: 36926308 PMCID: PMC10016624 DOI: 10.3389/fopht.2022.989002] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Visual processing starts at the retina of the eye, and signals are then transferred primarily to the visual cortex and the tectum. In the retina, multiple neural networks encode different aspects of visual input, such as color and motion. Subsequently, multiple neural streams in parallel convey unique aspects of visual information to cortical and subcortical regions. Bipolar cells, which are the second order neurons of the retina, separate visual signals evoked by light and dark contrasts and encode them to ON and OFF pathways, respectively. The interplay between ON and OFF neural signals is the foundation for visual processing for object contrast which underlies higher order stimulus processing. ON and OFF pathways have been classically thought to signal in a mirror-symmetric manner. However, while these two pathways contribute synergistically to visual perception in some instances, they have pronounced asymmetries suggesting independent operation in other cases. In this review, we summarize the role of the ON-OFF dichotomy in visual signaling, aiming to contribute to the understanding of visual recognition.
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Affiliation(s)
- Tomomi Ichinose
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, USA
- Correspondence: Tomomi Ichinose, MD, PhD,
| | - Samar Habib
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, USA
- Department of Medical Parasitology, Mansoura Faculty of Medicine, Mansoura University, Mansoura, Egypt
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11
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Rapid Analysis of Visual Receptive Fields by Iterative Tomography. eNeuro 2021; 8:ENEURO.0046-21.2021. [PMID: 34799410 PMCID: PMC8658541 DOI: 10.1523/eneuro.0046-21.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 11/02/2021] [Accepted: 11/12/2021] [Indexed: 11/21/2022] Open
Abstract
Many receptive fields in the early visual system show standard (center-surround) structure and can be analyzed using simple drifting patterns and a difference-of-Gaussians (DoG) model, which treats the receptive field as a linear filter of the visual image. But many other receptive fields show nonlinear properties such as selectivity for direction of movement. Such receptive fields are typically studied using discrete stimuli (moving or flashed bars and edges) and are modelled according to the features of the visual image to which they are most sensitive. Here, we harness recent advances in tomographic image analysis to characterize rapidly and simultaneously both the linear and nonlinear components of visual receptive fields. Spiking and intracellular voltage potential responses to briefly flashed bars are analyzed using non-negative matrix factorization (NNMF) and iterative reconstruction tomography (IRT). The method yields high-resolution receptive field maps of individual neurons and neuron ensembles in primate (marmoset, both sexes) lateral geniculate and rodent (mouse, male) retina. We show that the first two IRT components correspond to DoG-equivalent center and surround of standard [magnocellular (M) and parvocellular (P)] receptive fields in primate geniculate. The first two IRT components also reveal the spatiotemporal receptive field structure of nonstandard (on/off-rectifying) receptive fields. In rodent retina we combine NNMF-IRT with patch-clamp recording and dye injection to directly map spatial receptive fields to the underlying anatomy of retinal output neurons. We conclude that NNMF-IRT provides a rapid and flexible framework for study of receptive fields in the early visual system.
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12
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Grünert U, Lee SCS, Kwan WC, Mundinano IC, Bourne JA, Martin PR. Retinal ganglion cells projecting to superior colliculus and pulvinar in marmoset. Brain Struct Funct 2021; 226:2745-2762. [PMID: 34021395 DOI: 10.1007/s00429-021-02295-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/08/2021] [Indexed: 12/29/2022]
Abstract
We determined the retinal ganglion cell types projecting to the medial subdivision of inferior pulvinar (PIm) and the superior colliculus (SC) in the common marmoset monkey, Callithrix jacchus. Adult marmosets received a bidirectional tracer cocktail into the PIm (conjugated to Alexa fluor 488), and the SC (conjugated to Alexa fluor 594) using an MRI-guided approach. One SC injection included the pretectum. The large majority of retrogradely labelled cells were obtained from SC injections, with only a small proportion obtained after PIm injections. Retrogradely labelled cells were injected intracellularly in vitro using lipophilic dyes (DiI, DiO). The SC and PIm both received input from a variety of ganglion cell types. Input to the PIm was dominated by broad thorny (41%), narrow thorny (24%) and large bistratified (25%) ganglion cells. Input to the SC was dominated by parasol (37%), broad thorny (24%) and narrow thorny (17%) cells. Midget ganglion cells (which make up the large majority of primate retinal ganglion cells) and small bistratified (blue-ON/yellow OFF) cells were never observed to project to SC or PIm. Small numbers of other wide-field ganglion cell types were also encountered. Giant sparse (presumed melanopsin-expressing) cells were only seen following the tracer injection which included the pretectum. We note that despite the location of pulvinar complex in dorsal thalamus, and its increased size and functional importance in primate evolution, the retinal projections to pulvinar have more in common with SC projections than they do with projections to the dorsal lateral geniculate nucleus.
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Affiliation(s)
- Ulrike Grünert
- Save Sight Institute, Discipline of Clinical Ophthalmology, Sydney Medical School, The University of Sydney, 8 Macquarie Street, Sydney, NSW, 2000, Australia.
- Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, NSW, 2000, Australia.
| | - Sammy C S Lee
- Save Sight Institute, Discipline of Clinical Ophthalmology, Sydney Medical School, The University of Sydney, 8 Macquarie Street, Sydney, NSW, 2000, Australia
- Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, NSW, 2000, Australia
| | - William C Kwan
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | | | - James A Bourne
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | - Paul R Martin
- Save Sight Institute, Discipline of Clinical Ophthalmology, Sydney Medical School, The University of Sydney, 8 Macquarie Street, Sydney, NSW, 2000, Australia
- Australian Research Council Centre of Excellence for Integrative Brain Function, Sydney Node, The University of Sydney, Sydney, NSW, 2000, Australia
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13
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Solomon SG. Retinal ganglion cells and the magnocellular, parvocellular, and koniocellular subcortical visual pathways from the eye to the brain. HANDBOOK OF CLINICAL NEUROLOGY 2021; 178:31-50. [PMID: 33832683 DOI: 10.1016/b978-0-12-821377-3.00018-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
In primates including humans, most retinal ganglion cells send signals to the lateral geniculate nucleus (LGN) of the thalamus. The anatomical and functional properties of the two major pathways through the LGN, the parvocellular (P) and magnocellular (M) pathways, are now well understood. Neurones in these pathways appear to convey a filtered version of the retinal image to primary visual cortex for further analysis. The properties of the P-pathway suggest it is important for high spatial acuity and red-green color vision, while those of the M-pathway suggest it is important for achromatic visual sensitivity and motion vision. Recent work has sharpened our understanding of how these properties are built in the retina, and described subtle but important nonlinearities that shape the signals that cortex receives. In addition to the P- and M-pathways, other retinal ganglion cells also project to the LGN. These ganglion cells are larger than those in the P- and M-pathways, have different retinal connectivity, and project to distinct regions of the LGN, together forming heterogenous koniocellular (K) pathways. Recent work has started to reveal the properties of these K-pathways, in the retina and in the LGN. The functional properties of K-pathways are more complex than those in the P- and M-pathways, and the K-pathways are likely to have a distinct contribution to vision. They provide a complementary pathway to the primary visual cortex, but can also send signals directly to extrastriate visual cortex. At the level of the LGN, many neurones in the K-pathways seem to integrate retinal with non-retinal inputs, and some may provide an early site of binocular convergence.
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Affiliation(s)
- Samuel G Solomon
- Department of Experimental Psychology, University College London, London, United Kingdom.
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14
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Famiglietti EV. Morphological identification and systematic classification of mammalian retinal ganglion cells. I. Rabbit retinal ganglion cells. J Comp Neurol 2020; 528:3305-3450. [PMID: 32725618 DOI: 10.1002/cne.24998] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 07/21/2020] [Accepted: 07/21/2020] [Indexed: 11/10/2022]
Abstract
Retinal ganglion cells (RGCs) convey visual signals to 50 regions of the brain. For reasons of interest and convenience, they constitute an excellent system for the study of brain structure and function. There is general agreement that, absent a complete "parts list," understanding how the nervous system processes information will remain an elusive goal. Recent studies indicate that there are 30-50 types of ganglion cell in mouse retina, whereas only a few years ago it was still written that mice and the more visually oriented lagomorphs had less than 20 types of RGC. More than 30 years ago, I estimated that rabbits have about 40 types of RGC. The present study indicates that this number is much too low. I have employed the old but powerful method of Golgi-impregnation to rabbit retina, studying the range of component neurons in this already well-studied retinal system. Close quantitative and qualitative analyses of 1,142 RGCs in 26 retinas take into account cell body and dendritic field size, level(s) of dendritic stratification in the retina's inner plexiform layer, and details of dendritic branching. Ninety-one morphologies are recognized. Of these, at least 32 can be correlated with physiologically studied RGCs, dye-injected for morphological analysis. It is unlikely that rabbits have 91 types of RGC, but is argued here that this number lies between 60 and 70. The present study provides a "yardstick" for measuring the output of future molecular studies that may be more definitive in fixing the number of RGC types in rabbit retina.
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Affiliation(s)
- Edward V Famiglietti
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, Rhode Island, USA.,Division of Ophthalmology, Rhode Island Hospital, Providence, Rhode Island, USA
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15
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Turner EC, Gabi M, Liao CC, Kaas JH. The postnatal development of MT, V1, LGN, pulvinar and SC in prosimian galagos (Otolemur garnettii). J Comp Neurol 2020; 528:3075-3094. [PMID: 32067231 PMCID: PMC11495416 DOI: 10.1002/cne.24885] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/11/2020] [Accepted: 02/11/2020] [Indexed: 11/05/2022]
Abstract
Considerable evidence supports the premise that the visual system of primates develops hierarchically, with primary visual cortex developing structurally and functionally first, thereby influencing the subsequent development of higher cortical areas. An apparent exception is the higher order middle temporal visual area (MT), which appears to be histologically distinct near the time of birth in marmosets. Here we used a number of histological and immunohistological markers to evaluate the maturation of cortical and subcortical components of the visual system in galagos ranging from newborns to adults. Galagos are representative of the large strepsirrhine branch of primate evolution, and studies of these primates help identify brain features that are broadly similar across primate taxa. The histological results support the view that MT is functional at or near the time of birth, as is primary visual cortex. Likewise, the superior colliculus, dorsal lateral geniculate nucleus, and the posterior nucleus of the pulvinar are well-developed by birth. Thus, these subcortical structures likely provide visual information directly or indirectly to cortex in newborn galagos. We conclude that MT resembles a primary sensory area by developing early, and that the early development of MT may influence the subsequent development of dorsal stream visual areas.
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Affiliation(s)
- Emily C Turner
- Department of Psychology, Vanderbilt University, Nashville, Tennessee
| | - Mariana Gabi
- Department of Psychology, Vanderbilt University, Nashville, Tennessee
| | - Chia-Chi Liao
- Department of Psychology, Vanderbilt University, Nashville, Tennessee
| | - Jon H Kaas
- Department of Psychology, Vanderbilt University, Nashville, Tennessee
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16
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Liang L, Chen C. Organization, Function, and Development of the Mouse Retinogeniculate Synapse. Annu Rev Vis Sci 2020; 6:261-285. [DOI: 10.1146/annurev-vision-121219-081753] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Visual information is encoded in distinct retinal ganglion cell (RGC) types in the eye tuned to specific features of the visual space. These streams of information project to the visual thalamus, the first station of the image-forming pathway. In the mouse, this connection between RGCs and thalamocortical neurons, the retinogeniculate synapse, has become a powerful experimental model for understanding how circuits in the thalamus are constructed to process these incoming lines of information. Using modern molecular and genetic tools, recent studies have suggested a more complex circuit organization than was previously understood. In this review, we summarize the current understanding of the structural and functional organization of the retinogeniculate synapse in the mouse. We discuss a framework by which a seemingly complex circuit can effectively integrate and parse information to downstream stations of the visual pathway. Finally, we review how activity and visual experience can sculpt this exquisite connectivity.
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Affiliation(s)
- Liang Liang
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, Massachusetts 02115, USA
- Department of Neuroscience, Yale University, New Haven, Connecticut 06520, USA
| | - Chinfei Chen
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, Massachusetts 02115, USA
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17
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Abstract
The physiological response properties of neurons in the visual system are inherited mainly from feedforward inputs. Interestingly, feedback inputs often outnumber feedforward inputs. Although they are numerous, feedback connections are weaker, slower, and considered to be modulatory, in contrast to fast, high-efficacy feedforward connections. Accordingly, the functional role of feedback in visual processing has remained a fundamental mystery in vision science. At the core of this mystery are questions about whether feedback circuits regulate spatial receptive field properties versus temporal responses among target neurons, or whether feedback serves a more global role in arousal or attention. These proposed functions are not mutually exclusive, and there is compelling evidence to support multiple functional roles for feedback. In this review, the role of feedback in vision will be explored mainly from the perspective of corticothalamic feedback. Further generalized principles of feedback applicable to corticocortical connections will also be considered.
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Affiliation(s)
- Farran Briggs
- Departments of Neuroscience and Brain and Cognitive Sciences, Del Monte Institute for Neuroscience, and Center for Visual Science, University of Rochester, Rochester, New York 14642, USA;
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18
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Rima S, Schmid MC. V1-bypassing thalamo-cortical visual circuits in blindsight and developmental dyslexia. CURRENT OPINION IN PHYSIOLOGY 2020; 16:14-20. [PMID: 39649037 PMCID: PMC7617028 DOI: 10.1016/j.cophys.2020.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Vision rests on computations that primarily rely on the parvocellular and magnocellular geniculate relay of retinal signals to V1. Secondary pathways involving superior colliculus, koniocellular lateral geniculate nucleus and pulvinar and their V1-bypassing projections to higher order cortex are known to exist. While they may form an evolutionary old visual system, their contribution to perception and visually guided behaviour remain largely obscure. Recent developments in tract tracing and circuit manipulation technologies provide new insights. Here we discuss how secondary visual pathways mediate residual vision (blindsight) after V1 injury by relaying signals directly into higher order cortical areas. We contrast these findings on blindsight with new studies on dyslexia suggesting that dysfunction of secondary visual pathways might contribute to dyslexic's perceptual difficulties. Emerging from these considerations, secondary visual pathways involving koniocellular LGN may be critical for detection of visual change, whereas pulvinar function appears more linked to visuomotor planning.
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19
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Murphy AJ, Hasse JM, Briggs F. Physiological characterization of a rare subpopulation of doublet-spiking neurons in the ferret lateral geniculate nucleus. J Neurophysiol 2020; 124:432-442. [PMID: 32667229 DOI: 10.1152/jn.00191.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Interest in exploring homologies in the early visual pathways of rodents, carnivores, and primates has recently grown. Retinas of these species contain morphologically and physiologically heterogeneous retinal ganglion cells that form the basis for parallel visual information processing streams. Whether rare retinal ganglion cells with unusual visual response properties in carnivores and primates project to the visual thalamus and drive unusual visual responses among thalamic relay neurons is poorly understood. We surveyed neurophysiological responses among hundreds of lateral geniculate nucleus (LGN) neurons in ferrets and observed a novel subpopulation of LGN neurons displaying doublet-spiking waveforms. Some visual response properties of doublet-spiking LGN neurons, like contrast and temporal frequency tuning, were intermediate to those of X and Y LGN neurons. Interestingly, most doublet-spiking LGN neurons were tuned for orientation and displayed direction selectivity for horizontal motion. Spatiotemporal receptive fields of doublet-spiking neurons were diverse and included center/surround organization, On/Off responses, and elongated separate On and Off subregions. Optogenetic activation of corticogeniculate feedback did not alter the tuning or spatiotemporal receptive fields of doublet-spiking neurons, suggesting that their unusual tuning properties were inherited from retinal inputs. The doublet-spiking LGN neurons were found throughout the depth of LGN recording penetrations. Together these findings suggest that while extremely rare (<2% of recorded LGN neurons), unique subpopulations of LGN neurons in carnivores receive retinal inputs that confer them with nonstandard visual response properties like direction selectivity. These results suggest that neuronal circuits for nonstandard visual computations are common across a variety of species, even though their proportions vary.NEW & NOTEWORTHY Interest in visual system homologies across species has recently increased. Across species, retinas contain diverse retinal ganglion cells including cells with unusual visual response properties. It is unclear whether rare retinal ganglion cells in carnivores project to and drive similarly unique visual responses in the visual thalamus. We discovered a rare subpopulation of thalamic neurons defined by unique spike shape and visual response properties, suggesting that nonstandard visual computations are common to many species.
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Affiliation(s)
- Allison J Murphy
- Neuroscience Graduate Program, University of Rochester, Rochester, New York.,Center for Visual Science, University of Rochester, Rochester, New York
| | - J Michael Hasse
- Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine, Rochester, New York.,Center for Neural Science, New York University, New York, New York
| | - Farran Briggs
- Neuroscience Graduate Program, University of Rochester, Rochester, New York.,Center for Visual Science, University of Rochester, Rochester, New York.,Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine, Rochester, New York.,Department of Neuroscience, University of Rochester School of Medicine, Rochester, New York.,Department of Brain and Cognitive Sciences, University of Rochester, Rochester, New York
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20
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Munn B, Zeater N, Pietersen AN, Solomon SG, Cheong SK, Martin PR, Gong P. Fractal spike dynamics and neuronal coupling in the primate visual system. J Physiol 2020; 598:1551-1571. [DOI: 10.1113/jp278935] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/18/2019] [Indexed: 12/23/2022] Open
Affiliation(s)
- Brandon Munn
- School of Physics University of Sydney Sydney New South Wales 2006 Australia
- Australian Research Council Centre of Excellence for Integrative Brain Function University of Sydney Sydney New South Wales 2006 Australia
| | - Natalie Zeater
- Australian Research Council Centre of Excellence for Integrative Brain Function University of Sydney Sydney New South Wales 2006 Australia
- Save Sight Institute Eye Hospital Campus University of Sydney Sydney New South Wales 2001 Australia
| | - Alexander N. Pietersen
- Australian Research Council Centre of Excellence for Integrative Brain Function University of Sydney Sydney New South Wales 2006 Australia
- Save Sight Institute Eye Hospital Campus University of Sydney Sydney New South Wales 2001 Australia
| | - Samuel G. Solomon
- Discipline of Physiology University of Sydney Sydney New South Wales 2006 Australia
- Department of Experimental Psychology University College London London WC1P 0AH UK
| | - Soon Keen Cheong
- Australian Research Council Centre of Excellence for Integrative Brain Function University of Sydney Sydney New South Wales 2006 Australia
- Save Sight Institute Eye Hospital Campus University of Sydney Sydney New South Wales 2001 Australia
| | - Paul R. Martin
- Australian Research Council Centre of Excellence for Integrative Brain Function University of Sydney Sydney New South Wales 2006 Australia
- Save Sight Institute Eye Hospital Campus University of Sydney Sydney New South Wales 2001 Australia
- Discipline of Physiology University of Sydney Sydney New South Wales 2006 Australia
| | - Pulin Gong
- School of Physics University of Sydney Sydney New South Wales 2006 Australia
- Australian Research Council Centre of Excellence for Integrative Brain Function University of Sydney Sydney New South Wales 2006 Australia
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21
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Zhu D, McEwan A, Eiber C. Microelectrode array electrical impedance tomography for fast functional imaging in the thalamus. Neuroimage 2019; 198:44-52. [PMID: 31108212 DOI: 10.1016/j.neuroimage.2019.05.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/26/2019] [Accepted: 05/09/2019] [Indexed: 10/26/2022] Open
Abstract
Electrical Impedance Tomography (EIT) has the potential to be able to observe functional tomographic images of neural activity in the brain at millisecond time-scales. Prior modelling and experimental work has shown that EIT is capable of imaging impedance changes from neural depolarisation in rat somatosensory cortex. Here, we investigate the feasibility of EIT for imaging impedance changes using a stereotaxically implanted microelectrode array in the thalamus. Microelectrode array EIT was simulated using an anatomically accurate marmoset brain model. Impedance imaging was validated and detectability estimated using physiological noise recorded from the marmoset visual thalamus. The results suggest that visual-input-driven impedance changes in visual subcortical bodies within 300 μm of the implanted array could be reliably reconstructed and localised, comparable to local field potential measurements. Furthermore, we demonstrated that microelectrode array EIT could reconstruct concurrent activity in multiple subcortical bodies simultaneously.
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Affiliation(s)
- Danyi Zhu
- School of Electrical and Information Engineering, The University of Sydney, Camperdown, NSW, Australia
| | - Alistair McEwan
- School of Electrical and Information Engineering, The University of Sydney, Camperdown, NSW, Australia
| | - Calvin Eiber
- Save Sight Institute, The University of Sydney, 8 Macquarie St, Sydney, NSW, Australia; School of Medical Sciences, University of Sydney, Sydney, NSW, Australia; Australian Research Council Centre of Excellence for Integrative Brain Function, Australia.
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