Retinal ganglion cell coding in simulated active vision

2005 ◽  
Vol 22 (6) ◽  
pp. 789-806 ◽  
Author(s):  
FRANKLIN R. AMTHOR ◽  
JOHN S. TOOTLE ◽  
TIMOTHY J. GAWNE
Keyword(s):  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Retinal Image ◽  
Cell Function ◽  
Ganglion Cells ◽  
Active Vision ◽  
Global Changes ◽  
Retinal Ganglion ◽  
Luminance Change ◽  
Mean Luminance

The image on the retina is almost never static. Eye, head, and body movements, and externally generated motion create rapid and continual changes in the retinal image (“active vision”). Virtually all vision in animals such as primates, which make saccades as often as 3–4 times/s, is based on information that must be derived from the first few hundred milliseconds after sudden, global changes in the retinal image. These changes may be accompanied by large changes in area mean luminance, as well as higher order image contrast statistics. This study investigated how retinal ganglion cell responses, whose response properties have been typically studied and defined in a stable stimulus regime, are affected by sudden changes in mean luminance that are characteristic of active vision. Specifically, the steady-state responses of retinal ganglion cells to static or moving square-wave grating stimuli were recorded in an isolated, superfused rabbit eyecup preparation and compared to responses after saccade-like changes in luminance. The manner of coding after luminance changes was different for different ganglion cell classes; both suppression and enhancement of responses to patterns following luminance changes were found. Brisk-transient Off cells unambiguously signaled the darkening of the overall image, but were also modulated by the subsequently appearing grating stimulus. Several types of On-center cell behavior were observed, ranging from strong suppression of the subsequent response by luminance changes, to strong enhancement. Overall, most ganglion cells distinguished static patterns after a luminance change via differences in their spike discharges nearly as well as before, although there were clear asymmetries between the On and Off pathways. Changes in mean luminance in some ganglion cells, such as On–Off directionally selective ganglion cells, could create large phase shifts in the response to patterned, moving stimuli, although these stimuli were still detected immediately after luminance changes. The results of this study show that the image dynamics of active vision may be a fundamental challenge for the visual system because of strong effects on retinal ganglion cell function. However, rapid extraction of unambiguous information after luminance changes appears to be encoded in differences in the spike discharges in different retinal ganglion cell classes. Asymmetries among ganglion cell classes in sensitivity to luminance changes may provide a basis by which some provide the “context” for interpreting the firing of others.

scholarly journals Clinical electrophysiology of the optic nerve and retinal ganglion cells

Eye ◽  
2021 ◽  
Author(s):  
Oliver R. Marmoy ◽  
Suresh Viswanathan
Keyword(s):  
Optic Nerve ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Retinal Ganglion Cell ◽  
Cell Function ◽  
Ganglion Cells ◽  
Pattern Electroretinogram ◽  
Photopic Negative Response ◽  
Clinical Electrophysiology ◽  
Retinal Ganglion

AbstractClinical electrophysiological assessment of optic nerve and retinal ganglion cell function can be performed using the Pattern Electroretinogram (PERG), Visual Evoked Potential (VEP) and the Photopic Negative Response (PhNR) amongst other more specialised techniques. In this review, we describe these electrophysiological techniques and their application in diseases affecting the optic nerve and retinal ganglion cells with the exception of glaucoma. The disease groups discussed include hereditary, compressive, toxic/nutritional, traumatic, vascular, inflammatory and intracranial causes for optic nerve or retinal ganglion cell dysfunction. The benefits of objective, electrophysiological measurement of the retinal ganglion cells and optic nerve are discussed, as are their applications in clinical diagnosis of disease, determining prognosis, monitoring progression and response to novel therapies.

scholarly journals Nicotinamide provides neuroprotection in glaucoma by protecting against mitochondrial and metabolic dysfunction

2020 ◽  
Author(s):  
James R Tribble ◽  
Amin Otmani ◽  
Shanshan Sun ◽  
Sevannah A Ellis ◽  
Gloria Cimaglia ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Neurodegenerative Disease ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Retinal Ganglion Cell ◽  
Cell Function ◽  
Ganglion Cells ◽  
Neuroprotective Effect ◽  
Retinal Ganglion ◽  
Neuroprotective Therapy

AbstractNicotinamide adenine dinucleotide (NAD) is a REDOX cofactor and metabolite essential for neuronal survival. Glaucoma is a common neurodegenerative disease in which neuronal levels of NAD decline. Repleting NAD via dietary supplementation of nicotinamide (a precursor to NAD) is effective in preventing retinal ganglion cell neurodegeneration in mouse models. Supporting this, short-term oral nicotinamide treatment in human glaucoma patients provides a recovery of retinal ganglion cell function implying a protection of visual function. Despite this, the mechanism of neuroprotection and full effects of nicotinamide on retinal ganglion cells is unclear. Glaucoma is a complex neurodegenerative disease in which a mix of healthy, stressed, and degenerating retinal ganglion cells co-exist, and in which retinal ganglion cells display compartmentalized degeneration across their visual trajectory. Therefore, we assess the effects of nicotinamide on retinal ganglion cells in normal physiological conditions and across a range of glaucoma relevant insults. We confirm neuroprotection afforded by nicotinamide in rodent models which represent isolated ocular hypertensive, axon degenerative, and mitochondrial degenerative insults. We define a small molecular weight metabolome for the retina, optic nerve, and superior colliculus which demonstrates that ocular hypertension induces widespread metabolic disruption that can be prevented by nicotinamide. Nicotinamide provides these neuroprotective effects by increasing oxidative phosphorylation, buffering and preventing metabolic stress, and increasing mitochondrial size and motility whilst simultaneously dampening action potential firing frequency. These data support continued determination of the utility of long-term NAM treatment as a neuroprotective therapy for human glaucoma.One Sentence SummaryThe NAD precursor nicotinamide has a potent neuroprotective effect in the retina and optic nerve, targeting neuronal function, metabolism, and mitochondrial function.

scholarly journals Dynamic Expression of HDAC3 in db/db Mouse RGCs and Its Relationship with Apoptosis and Autophagy

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Yuhong Fu ◽  
Ying Wang ◽  
Xinyuan Gao ◽  
Huiyao Li ◽  
Yue Yuan
Keyword(s):  
Diabetic Retinopathy ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Retinal Ganglion Cell ◽  
Ganglion Cells ◽  
Control Group ◽  
Diabetic Patients ◽  
Retinal Ganglion ◽  
Glucose Levels ◽  
Dynamic Expression

Background. Diabetic retinopathy (DR) is a severe complication of diabetes mellitus. DR is considered as a neurovascular disease. Retinal ganglion cell (RGC) loss plays an important role in the vision function disorder of diabetic patients. Histone deacetylase3 (HDAC3) is closely related to injury repair and nerve regeneration. The correlation between HDAC3 and retinal ganglion cells in diabetic retinopathy is still unclear yet. Methods. To investigate the chronological sequence of the abnormalities of retinal ganglion cells in diabetic retinopathy, we choose 15 male db/db mice (aged 8 weeks, 12 weeks, 16 weeks, 18 weeks, and 25 weeks; each group had 3 mice) as diabetic groups and 3 male db/m mice (aged 8 weeks) as the control group. In this study, we examined the morphological and immunohistochemical changes of HDAC3, Caspase3, and LC3B in a sequential manner by characterizing the process of retinal ganglion cell variation. Results. Blood glucose levels and body weights of db/db mice were significantly higher than that of the control group, P<0.01. Compared with the control group, the number of retinal ganglion cells decreased with the duration of disease increasing. HDAC3 expression gradually increased in RGCs of db/db mice. Caspase3 expression gradually accelerated in RGCs of db/db mice. LC3B expression dynamically changed in RGCs of db/db mice. HDAC3 was positively correlated with Caspase3 expression (r=0.7424), P<0.01. HDAC3 was positively correlated with LC3B expression (r=0.7336), P<0.01. Discussion. We clarified the dynamic expression changes of HDAC3, Caspase3, and LC3B in retinal ganglion cells of db/db mice. Our results suggest the HDAC3 expression has a positive correlation with apoptosis and autophagy.

scholarly journals HE3286 Reduces Axonal Loss and Preserves Retinal Ganglion Cell Function in Experimental Optic Neuritis

2014 ◽  
Vol 55 (9) ◽  
pp. 5744 ◽  
Author(s):  
Reas S. Khan ◽  
Kimberly Dine ◽  
Esteban Luna ◽  
Clarence Ahlem ◽  
Kenneth S. Shindler
Keyword(s):  
Optic Neuritis ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Cell Function ◽  
Axonal Loss ◽  
Retinal Ganglion ◽  
Retinal Ganglion Cell Function

scholarly journals Neuroprotection of retinal ganglion cells by the sigma-1 receptor agonist pridopidine in models of experimental glaucoma

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Michal Geva ◽  
Noga Gershoni-Emek ◽  
Luana Naia ◽  
Philip Ly ◽  
Sandra Mota ◽  
...  
Keyword(s):  
Ganglion Cell ◽  
Retinal Degeneration ◽  
Retinal Ganglion Cells ◽  
Retinal Ganglion Cell ◽  
Ganglion Cells ◽  
Neuroprotective Effect ◽  
Retinal Ganglion ◽  
Cell Degeneration ◽  
Sigma 1 Receptor ◽  
Sigma 1

AbstractOptic neuropathies such as glaucoma are characterized by retinal ganglion cell (RGC) degeneration and death. The sigma-1 receptor (S1R) is an attractive target for treating optic neuropathies as it is highly expressed in RGCs, and its absence causes retinal degeneration. Activation of the S1R exerts neuroprotective effects in models of retinal degeneration. Pridopidine is a highly selective and potent S1R agonist in clinical development. We show that pridopidine exerts neuroprotection of retinal ganglion cells in two different rat models of glaucoma. Pridopidine strongly binds melanin, which is highly expressed in the retina. This feature of pridopidine has implications to its ocular distribution, bioavailability, and effective dose. Mitochondria dysfunction is a key contributor to retinal ganglion cell degeneration. Pridopidine rescues mitochondrial function via activation of the S1R, providing support for the potential mechanism driving its neuroprotective effect in retinal ganglion cells.

scholarly journals Bicycronic construct for optogenetic prosthesis of ganglion cell receptive field of degenerated retina

2019 ◽  
Vol 486 (2) ◽  
pp. 258-261
Author(s):  
L. E. Petrovskaya ◽  
M. V. Roshchin ◽  
G. R. Smirnova ◽  
D. E. Kolotova ◽  
P. M. Balaban ◽  
...  
Keyword(s):  
Receptive Field ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Distinctive Feature ◽  
Action Potentials ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Light Stimulation ◽  
Genetic Construct ◽  
Stimulation Of

For the purpose of optogenetic prosthetics of the receptive field of the retinal ganglion cell, we have created a bicistronic genetic construct that carries genes of excitatory (channelorhodopsin2) and inhibitory (anionic channelorhodopsin) rhodopsins. A distinctive feature of this construct is the combination of two genes into one construct with the mutant IRES inserted between them, which ensures precise ratio of the expression levels of the first and second gene in each transfected cell. It was found that the illumination of the central part of transfected neuron with light with a wavelength of 470 nm causes the generation of action potentials in the cell. At the same time, light stimulation of the periphery of the neuron causes cessation of the generation of action potentials. Thus, we were able to simulate the ON-OFF interaction of the receptive field of the retinal ganglion cell using optogenetic methods. Theoretically, this construction can be used for optogenetic prosthetics of degenerative retina in case of its delivery to ganglion cells using lentiviral vectors.

All Brn3 genes can promote retinal ganglion cell differentiation in the chick

Development ◽  
2000 ◽  
Vol 127 (15) ◽  
pp. 3237-3247 ◽  
Author(s):  
W. Liu ◽  
S.L. Khare ◽  
X. Liang ◽  
M.A. Peters ◽  
X. Liu ◽  
...  
Keyword(s):  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Ganglion Cells ◽  
Cell Development ◽  
Large Set ◽  
Retinal Ganglion ◽  
Pou Domain ◽  
Temporal Expression Pattern ◽  
Cell Genesis

Targeted gene disruption studies in the mouse have demonstrated crucial roles for the Brn3 POU domain transcription factor genes, Brn3a, Brn3b, Brn3c (now called Pou4f1, Pou4f2, Pou4f3, respectively) in sensorineural development and survival. During mouse retinogenesis, the Brn3b gene is expressed in a large set of postmitotic ganglion cell precursors and is required for their early and terminal differentiation. In contrast, the Brn3a and Brn3c genes, which are expressed later in ganglion cells, appear to be dispensable for ganglion cell development. To understand the mechanism that causes the functional differences of Brn3 genes in retinal development, we employed a gain-of-function approach in the chick embryo. We find that Brn3b(l) and Brn3b(s), the two isoforms encoded by the Brn3b gene, as well as Brn3a and Brn3c all have similar DNA-binding and transactivating activities. We further find that the POU domain is minimally required for these activities. Consequently, we show that all these Brn3 proteins have a similar ability to promote development of ganglion cells when ectopically expressed in retinal progenitors. During chick retinogenesis, cBrn3c instead of cBrn3b exhibits a spatial and temporal expression pattern characteristic of ganglion cell genesis and its misexpression can also increase ganglion cell production. Based on these data, we propose that all Brn3 factors are capable of promoting retinal ganglion cell development, and that this potential may be limited by the order of expression in vivo.

scholarly journals Midget retinal ganglion cell dendritic and mitochondrial degeneration is an early feature of human glaucoma

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
James R Tribble ◽  
Asta Vasalauskaite ◽  
Tony Redmond ◽  
Robert D Young ◽  
Shoaib Hassan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Animal Models ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Retinal Ganglion Cell ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Face Scanning ◽  
Block Face ◽  
Scanning Electron

Abstract Glaucoma is characterized by the progressive dysfunction and loss of retinal ganglion cells. However, the earliest degenerative events that occur in human glaucoma are relatively unknown. Work in animal models has demonstrated that retinal ganglion cell dendrites remodel and atrophy prior to the loss of the cell soma. Whether this occurs in human glaucoma has yet to be elucidated. Serial block face scanning electron microscopy is well established as a method to determine neuronal connectivity at high resolution but so far has only been performed in normal retina from animal models. To assess the structure–function relationship of early human glaucomatous neurodegeneration, regions of inner retina assessed to have none-to-moderate loss of retinal ganglion cell number were processed using serial block face scanning electron microscopy (n = 4 normal retinas, n = 4 glaucoma retinas). This allowed detailed 3D reconstruction of retinal ganglion cells and their intracellular components at a nanometre scale. In our datasets, retinal ganglion cell dendrites degenerate early in human glaucoma, with remodelling and redistribution of the mitochondria. We assessed the relationship between visual sensitivity and retinal ganglion cell density and discovered that this only partially conformed to predicted models of structure–function relationships, which may be affected by these early neurodegenerative changes. In this study, human glaucomatous retinal ganglion cells demonstrate compartmentalized degenerative changes as observed in animal models. Importantly, in these models, many of these changes have been demonstrated to be reversible, increasing the likelihood of translation to viable therapies for human glaucoma.

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