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Optic Nerve Signals in a Neuromorphic Chip I: Outer and Inner Retina Models

K.A. Zaghloul, K. Boahen
2004 IEEE Transactions on Biomedical Engineering  
Thus, this inner retina model realizes temporal frequency adaptation as well as contrast gain control.We present CMOS circuit designs for our retina model in this paper as well.  ...  We present a novel model for the mammalian retina and analyze its behavior. Our outer retina model performs bandpass spatiotemporal filtering.  ...  In this paper, we present a novel model for how the outer and inner retina process visual information, implement this model in silicon, and analyze its behavior.  ... 
doi:10.1109/tbme.2003.821039 pmid:15072220 fatcat:e2t7hhtcgrbtlm6hrbpko4pyya

Optic Nerve Signals in a Neuromorphic Chip II: Testing and Results

K.A. Zaghloul, K. Boahen
2004 IEEE Transactions on Biomedical Engineering  
To model the four main output (ganglion) cell types found in the retina, we morphed outer and inner retina circuits into a 96 x 60-photoreceptor, 3.5 x 3.3 mm 2 , 0.35 μm-CMOS chip.  ...  This chip, which is the first silicon retina to successfully model inner retina circuitry, approaches the spatial density of the retina.  ...  Finally, in Section VI, we demonstrate that our inner retina model realizes contrast gain control and compare the chip's GC responses with our analytical results. Section VII concludes the paper.  ... 
doi:10.1109/tbme.2003.821040 pmid:15072221 fatcat:sddfu3w7ljdabhftwyfs7vfr5m

A silicon retina that reproduces signals in the optic nerve

Kareem A Zaghloul, Kwabena Boahen
2006 Journal of Neural Engineering  
We demonstrate how the responses of our device's ganglion cells compare to those measured from the mammalian retina.  ...  We demonstrate how the responses of our device's ganglion cells compare to those measured from the mammalian retina.  ...  We are grateful to P Sterling and J Demb for discussions about the retinal microcircuits. We are also grateful to P Sterling and J Demb for assistance in preparation of this document.  ... 
doi:10.1088/1741-2560/3/4/002 pmid:17124329 fatcat:v2cqk26tgbeavhwwxpq4hfwswa

Effect of boundaries on the response of a neural network

L. Sirovich, S.E. Brodie, B.W. Knight
1979 Biophysical Journal  
The effect an abrupt boundary has upon the dynamical response of a neural network is investigated. The retina of the Limulus eye is used as a model system for studying this effect.  ...  A theoretical technique is presented for the quantitative prediction of the manner in which this neural network responds in the vicinity of its boundary.  ...  We thank Professor Floyd Ratliff, who directed us to this problem, for his participation and encouragement in this project. This work was supported in part by grants from the U.S.  ... 
doi:10.1016/s0006-3495(79)85191-7 pmid:262559 pmcid:PMC1328648 fatcat:ehmkn47z3ncgnaetitbges5liq

Maximizing contrast resolution in the outer retina of mammals

Mikhail Y. Lipin, Robert G. Smith, W. Rowland Taylor
2010 Biological cybernetics  
We modeled the outer retina as a continuous 2D extension of the discrete 1D model of Yagi et al. (Proc Int Joint Conf Neural Netw 1: 787-789, 1989).  ...  We determined the spatiotemporal impulse response of the model using small-signal analysis, assuming that the stimulus did not perturb the resting state of the feedback system.  ...  Acknowledgments Authors are grateful to Patrick Roberts, Victor Gurfinkel, and Orin Packer for their valuable comments. The study was supported by NEI grants EY017095 and EY016607.  ... 
doi:10.1007/s00422-010-0385-7 pmid:20361204 pmcid:PMC2932674 fatcat:uf4hsc2qkjdjzkirxniylgikxi

Differential Progression of Structural and Functional Alterations in Distinct Retinal Ganglion Cell Types in a Mouse Model of Glaucoma

L. Della Santina, D. M. Inman, C. B. Lupien, P. J. Horner, R. O. L. Wong
2013 Journal of Neuroscience  
Using a microbead injection technique to chronically raise IOP for 15 or 30 d in mice, we identified the early changes in visual response properties of different types of retinal ganglion cells (RGCs)  ...  In contrast, although the light-evoked responses of OFF-sustained RGCs were perturbed, the dendritic arbor of this cell type remained intact.  ...  Our observations lead us to propose a plausible model for the sequence of changes in RGC dendrites in response to IOP elevation.  ... 
doi:10.1523/jneurosci.5461-12.2013 pmid:24174678 pmcid:PMC3812509 fatcat:euuz4klzkvepzhklfizlriepim

Neuroprotection of retinal ganglion cell function and their central nervous system targets

M Vidal-Sanz, P de la Villa, M Avilés-Trigueros, S Mayor-Torroglosa, M Salinas-Navarro, L Alarcón-Martínez, M P Villegas-Pérez
2007 Eye (London. 1987)  
Functionally, this implies a permanent disconnection of the retina from its main retinorecipient target region in the brain.  ...  In animal models, it has been shown how retinal ischaemia induces profound functional and structural alterations of the inner retinal and RGC layers by 3 months.  ...  We thank M Elena Aguilera-Meseguer, Antonio García Avilés, Lidia Coll, Isabel Cánovas, Maribel Soro and José M Bernal-Garro for technical support.  ... 
doi:10.1038/sj.eye.6702888 fatcat:escjss2psvg4vorr7u3xk5qdle

Short-Term Increases in Transient Receptor Potential Vanilloid-1 Mediate Stress-Induced Enhancement of Neuronal Excitation

C. Weitlauf, N. J. Ward, W. S. Lambert, T. N. Sidorova, K. W. Ho, R. M. Sappington, D. J. Calkins
2014 Journal of Neuroscience  
Here we probed the mechanism of the influence of TRPV1 on ganglion cell survival in mouse models of glaucoma.  ...  Progression of neurodegeneration in disease and injury is influenced by the response of individual neurons to stressful stimuli and whether this response includes mechanisms to counter declining function  ...  The increase in TRPV1 was transient, diminishing to levels in saline retina by 5 weeks.  ... 
doi:10.1523/jneurosci.3424-14.2014 pmid:25392504 pmcid:PMC4228139 fatcat:6u2zkgaanzfd5lyrhnsfp2ubpu

Virtual Retina: A biological retina model and simulator, with contrast gain control

Adrien Wohrer, Pierre Kornprobst
2008 Journal of Computational Neuroscience  
The underlying model includes a linear model of filtering in the Outer Plexiform Layer, a shunting feedback at the level of bipolar cells accounting for rapid contrast gain control, and a spike generation  ...  This software will be an evolutionary tool for neuroscientists that need realistic large-scale input spike trains in subsequent treatments, and for educational purposes.  ...  Acknowledgements Many thanks to Thierry Viéville for his enthusiasm, and his involvement in defining the early tracks of this research.  ... 
doi:10.1007/s10827-008-0108-4 pmid:18670870 fatcat:pa5hwvstbvallm6m6xjp4pkm4q

Emulation of retinal cell responses during fixational eye movements

Jun Hasegawa, Tetsuya Yagi
2010 IEICE Electronics Express  
of the retina.  ...  The system developed in the present study can emulate retinal responses to natural scenes during fixational eye movements, and it can be used to realistically and effectively analyze the visual functions  ...  It is worth noting that these emulated results can not be obviously inferred from the analytical deduction made using the retinal models because of the eclectic complexities included in the system.  ... 
doi:10.1587/elex.7.184 fatcat:bnhnyrk66bai7mcv5vkjqzuiky

The nss mutation or lanthanum inhibits light-induced Ca2+ influx into fly photoreceptors

A. Rom-Glas
1992 The Journal of General Physiology  
In the ms mutant in response to intense prolonged light, the receptor potential declines to baseline during light while the Ca 2+ signal is almost abolished, revealing only a short transient reduction  ...  Prolonged dim lights induced a steady reduction in [Ca2+]o during light in the retina of normal Lucilia, while relatively litde change in [Ca2+]o was observed in the retina of the nss mutant.  ...  Feiler for developing the recording program and Dr. R. C. Hardie and Dr. Z. Selinger for critical reading of the manuscript.  ... 
doi:10.1085/jgp.100.5.767 pmid:1335476 pmcid:PMC2229113 fatcat:fbhfoendifdxrit5xmoj7jzve4

Gap junctions with amacrine cells provide a feedback pathway for ganglion cells within the retina

G. T. Kenyon, D. W. Marshak
1998 Proceedings of the Royal Society of London. Biological Sciences  
According to our model, the coupled amacrine cells enhance the responses of parasol cells to luminance contrast by disinhibition.  ...  We also show how a mixed chemical and electrical synapse between two sets of amacrine cells presynaptic to the parasol cells might make the responses of parasol cells more transient and, therefore, more  ...  The authors gratefully acknowledge grant EY 06472 from the National Eye Institute and the University of Texas Collaborative Research Program.  ... 
doi:10.1098/rspb.1998.0379 pmid:9633113 pmcid:PMC1689057 fatcat:o6tew64kjfarhnltyuik3dnck4

Learning the Gestalt Rule of Collinearity from Object Motion

Carsten Prodöhl, Rolf P. Würtz, Christoph von der Malsburg
2003 Neural Computation  
We show that it is crucial for successful learning to use the correlation of the transient responses instead of the sustained ones.  ...  The model uses spatiotemporal retinal filtering, which is very sensitive to changes in the visual input.  ...  These discrete approximations of the retina model are essential because their output is used in the model for the cortical layer.  ... 
doi:10.1162/08997660360675071 pmid:14511516 fatcat:nf6prvdl6bgh7kbv2l5hj7nqi4

Unattended motion-detection system based on the mammalian retina

Jose A. Martin-Pereda, Ana P. Gonzalez-Marcos, Edward M. Carapezza
2004 Unmanned/Unattended Sensors and Sensor Networks  
A simple unit, based in a previous optical logic cell employed in optical computing, is the basis for emulating the different behaviours of the biological neurons.  ...  The configuration adopted responds to the internal structure of the mammalian retina, where just five types of cells arranged in five layers are able to differentiate a large number of characteristics  ...  Ganglion cell G2 responds transiently to retinal illumination, much as the transient amacrine cells do. This type of response is the one adopted in our model.  ... 
doi:10.1117/12.578292 fatcat:hnvcludm3raz3ehc3u2ru3kaqy

Paying Attention with the Latest Technology

Parastoo Hashemi, R. Mark Wightman
2007 Neuron  
Visual information is first received in the retina.  ...  The technique is very powerful in the wealth of chemical information it provides because samples can be investigated for a number of neurotransmitters and neuropeptides with a number of analytical methods  ... 
doi:10.1016/j.neuron.2007.09.022 pmid:17920007 fatcat:itwz5ov3jra65pld3lmqvy3aey
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