scholarly journals Clinical review of retinotopy

2021 ◽  
pp. bjophthalmol-2021-320563
Author(s):  
Jenny Nij Bijvank ◽  
Lucas Maillette de Buy Wenniger ◽  
Pim de Graaf ◽  
Axel Petzold
Keyword(s):  
Optic Nerve ◽  
Visual System ◽  
Axonal Degeneration ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Anatomical Basis ◽  
Neuroprotective Strategies ◽  
Technical Advances ◽  
Clinical Practise ◽  
Dorsal Lateral Geniculate

Two observations made 29 years apart are the cornerstones of this review on the contributions of Dr Gordon T. Plant to understanding pathology affecting the optic nerve. The first observation laid the anatomical basis in 1990 for the interpretation of optical coherence tomography (OCT) findings in 2009. Retinal OCT offers clinicians detailed in vivo structural imaging of individual retinal layers. This has led to novel observations which were impossible to make using ophthalmoscopy. The technique also helps to re-introduce the anatomically grounded concept of retinotopy to clinical practise. This review employs illustrations of the anatomical basis for retinotopy through detailed translational histological studies and multimodal brain-eye imaging studies. The paths of the prelaminar and postlaminar axons forming the optic nerve and their postsynaptic path from the dorsal lateral geniculate nucleus to the primary visual cortex in humans are described. With the mapped neuroanatomy in mind we use OCT-MRI pairings to discuss the patterns of neurodegeneration in eye and brain that are a consequence of the hard wired retinotopy: anterograde and retrograde axonal degeneration which can, within the visual system, propagate trans-synaptically. The technical advances of OCT and MRI for the first time enable us to trace axonal degeneration through the entire visual system at spectacular resolution. In conclusion, the neuroanatomical insights provided by the combination of OCT and MRI allows us to separate incidental findings from sinister pathology and provides new opportunities to tailor and monitor novel neuroprotective strategies.

scholarly journals Mechanisms of acute axonal degeneration in the optic nerve in vivo

2010 ◽  
Vol 107 (13) ◽  
pp. 6064-6069 ◽  
Author(s):  
J. Knoferle ◽  
J. C. Koch ◽  
T. Ostendorf ◽  
U. Michel ◽  
V. Planchamp ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Axonal Degeneration

Distribution and specificity of S-cone (“blue cone”) signals in subcortical visual pathways

2014 ◽  
Vol 31 (2) ◽  
pp. 177-187 ◽  
Author(s):  
PAUL R. MARTIN ◽  
BARRY B. LEE
Keyword(s):  
Receptive Field ◽  
Visual System ◽  
Lateral Geniculate Nucleus ◽  
Receptive Fields ◽  
Visual Pathways ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Visual Systems ◽  
Dorsal Lateral Geniculate ◽  
Subcortical Visual Pathways ◽  
Marmoset Monkeys

AbstractWe review here the distribution of S-cone signals and properties of S-cone recipient receptive fields in subcortical pathways. Nearly everything we know about S-cone signals in the subcortical visual system comes from the study of visual systems in cats and primates (monkeys); in this review, we concentrate on results from macaque and marmoset monkeys. We discuss segregation of S-cone recipient (blue-on and blue-off) receptive fields in the dorsal lateral geniculate nucleus and describe their receptive field properties. We treat in some detail the question of detecting weak S-cone signals as an introduction for newcomers to the field. Finally, we briefly consider the question on how S-cone signals are distributed among nongeniculate targets.

scholarly journals Loss of Binocular Responses and Reduced Retinal Convergence During the Period of Retinogeniculate Axon Segregation

2006 ◽  
Vol 96 (5) ◽  
pp. 2775-2784 ◽  
Author(s):  
Jokūbas Z̆iburkus ◽  
William Guido
Keyword(s):  
Optic Nerve ◽  
Ganglion Cells ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Retinal Ganglion ◽  
Retinal Projections ◽  
Axon Terminals ◽  
Age Related ◽  
Dorsal Lateral Geniculate ◽  
Anterograde Labeling

In the developing mammalian visual system, axon terminals from the two eyes overlap in the dorsal lateral geniculate nucleus (LGN) but then undergo a period of refinement and segregate to form distinct eye-specific domains. We report on the changes in synaptic transmission that occur in rodent LGN during the period of retinogeniculate axon segregation by using anterograde labeling techniques in conjunction with an in vitro preparation where large segments of each optic nerve are preserved. Anterograde labeling of retinal projections in early postnatal day (P) rats with cholera toxin β subunit indicated an age-related recession in uncrossed retinal projections. Between P2 and P5 uncrossed projections occupied as much as 50% of the LGN and overlapped substantially with crossed projections. Between the first and second postnatal week uncrossed projections receded, so by P14 they assumed an adultlike profile occupying 15–20% of LGN and showed little or no overlap with crossed projections. The postsynaptic responses of LGN cells evoked by the separate stimulation of each optic nerve indicated that before P14, many relay cells were binocularly innervated and received at least four to six inputs from each eye. However, these features of retinogeniculate connectivity were transient and their attrition occurred in concert with a retraction of retinal arbors into nonoverlapping, eye-specific regions. By P18 cells were monocularly innervated and received input from one to three retinal ganglion cells. These results provide a better understanding of the underlying changes in synaptic circuitry that occur during the anatomical segregation of retinal inputs into eye-specific territories.

scholarly journals Visual responses in the dorsal lateral geniculate nucleus at early stages of retinal degeneration in rd1 PDE6β mice

2019 ◽  
Vol 122 (4) ◽  
pp. 1753-1764
Author(s):  
Christopher A. Procyk ◽  
Annette E. Allen ◽  
Franck P. Martial ◽  
Robert J. Lucas
Keyword(s):  
Retinal Degeneration ◽  
Lateral Geniculate Nucleus ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Cone Photoreceptors ◽  
Visual Responses ◽  
Lateral Geniculate ◽  
Lower Amplitude ◽  
Dorsal Lateral Geniculate ◽  
Rod And Cone Photoreceptors

Inherited retinal degenerations encompass a wide range of diseases that result in the death of rod and cone photoreceptors, eventually leading to irreversible blindness. Low vision survives at early stages of degeneration, at which point it could rely on residual populations of rod/cone photoreceptors as well as the inner retinal photoreceptor, melanopsin. To date, the impact of partial retinal degeneration on visual responses in the primary visual thalamus (dorsal lateral geniculate nucleus, dLGN) remains unknown, as does their relative reliance on surviving rod and cone photoreceptors vs. melanopsin. To answer these questions, we recorded visually evoked responses in the dLGN of anesthetized rd1 mice using in vivo electrophysiology at an age (3–5 wk) at which cones are partially degenerate and rods are absent. We found that excitatory (ON) responses to light had lower amplitude and longer latency in rd1 mice compared with age-matched visually intact controls; however, contrast sensitivity and spatial receptive field size were largely unaffected at this early stage of degeneration. Responses were retained when those wavelengths to which melanopsin is most sensitive were depleted, indicating that they were driven primarily by surviving cones. Inhibitory responses appeared absent in the rd1 thalamus, as did light-evoked gamma oscillations in firing. This description of fundamental features of the dLGN visual response at this intermediate stage of retinal degeneration provides a context for emerging attempts to restore vision by introducing ectopic photoreception to the degenerate retina. NEW & NOTEWORTHY This study provides new therapeutically relevant insights to visual responses in the dorsal lateral geniculate nucleus during progressive retinal degeneration. Using in vivo electrophysiology, we demonstrate that visual responses have lower amplitude and longer latency during degeneration, but contrast sensitivity and spatial receptive fields remain unaffected. Such visual responses are driven predominantly by surviving cones rather than melanopsin photoreceptors. The functional integrity of this visual pathway is encouraging for emerging attempts at visual restoration.

Subdivisions of the visual system labeled with the Cat-301 antibody in tree shrews

1994 ◽  
Vol 11 (4) ◽  
pp. 731-741 ◽  
Author(s):  
Neeraj Jain ◽  
Todd M. Preuss ◽  
Jon H. Kaas
Keyword(s):  
Visual System ◽  
Dorsal Lateral Geniculate Nucleus ◽  
M Cell ◽  
Macaque Monkeys ◽  
Tree Shrews ◽  
Area 18 ◽  
Visual Thalamus ◽  
Cortical Areas ◽  
Y Cells ◽  
Dorsal Lateral Geniculate

AbstractThe monoclonal antibody Cat-301 was used to stain neurons and neuropil in the visual thalamus and cortex of tree shrews —small, highly visual mammals that are closely related to primates. Previously, this antibody has been found to label neurons associated with the Y-cell stream of processing in cats and the magnocellular or M-cell stream in macaque monkeys. In tree shrews, the antibody selectively labeled layers 1, 2, 4, and 5 of the dorsal lateral geniculate nucleus, layers that are likely to contain neurons previously classified as Y-cells. Of the two layers that contain W-cells, layer 3 was unlabeled and layer 6 was lightly labeled. In area 17, layer 3c was densely stained, as in cats and macaque monkeys. The external half of layer 5 was also densely stained, in contrast to cats where the internal half of layer 5 is stained and macaques where layer 5 is sparsely stained. Area 18 was characterized by dense, uniform staining of inner layer 3 and outer layer 5, but no pattern of alternating light and dense bands crossed the width of area 18 as in macaques. Dense labeling of these same sublayers occurred in cortical areas TA and TD just lateral to area 18. Area TD may be the homologue of area MT of primates, which also stains densely with Cat-301 in macaques. These results indicate that Cat-301 differentially labels layers and areas in the visual system of tree shrews, and raise intriguing issues of comparison among tree shrews, primates, and cats.

scholarly journals Mechanisms of functional plasticity in subcortical visual areas

2021 ◽  
Author(s):  
Mael Dumenieu ◽  
Beatrice Marqueze-Pouey ◽  
Michael Russier ◽  
Dominique Debanne
Keyword(s):  
Visual System ◽  
Superior Colliculus ◽  
Neuronal Plasticity ◽  
Molecular Mechanisms ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Functional Plasticity ◽  
Cortical Areas ◽  
Visual Areas ◽  
Dorsal Lateral Geniculate ◽  
Activity Dependent

Visual plasticity is classically considered to occur essentially in the primary and secondarycortical areas. Subcortical visual areas such as the dorsal lateral geniculate nucleus (dLGN)or the superior colliculus (SC) have long been held as basic structures responsible for a stableand defined function. In this model, the dLGN was considered as a relay of visual informationtravelling from the retina to cortical areas and the SC as a sensory integrator orienting bodymovements towards visual targets. However, recent findings suggest that both dLGN and SCneurons express functional plasticity, adding unexplored layers of complexity to theirpreviously attributed functions. The existence of neuronal plasticity at the level of visualsubcortical areas redefines our approach of the visual system. The aim of this paper istherefore to review the cellular and molecular mechanisms for activity-dependent plasticity ofsynaptic transmission and of cellular properties in subcortical visual areas.

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