Light Microscopy Study of the Retina of the Yellow-Legged Gull, Larus Michahellis, and the Relationship between Environment and Behaviour

2018 ◽  
Vol 11 (4) ◽  
pp. 231-237 ◽  
Author(s):  
M.N. Vidal ◽  
Y. Segovia ◽  
N. Victory ◽  
A. Navarro-Sempere ◽  
M. García
Keyword(s):  
Light Microscopy ◽  
Visual Processing ◽  
Ganglion Cells ◽  
Morphological Characteristics ◽  
Amacrine Cells ◽  
Microscopy Study ◽  
Oil Droplets ◽  
Good Ability ◽  
Area Centralis ◽  
Larus Michahellis

The morphology of the retina of the adult Yellow-legged Gull, Larus michahellis, was examined in transverse sections under light microscopy in order to study the retinal adaptations to their specific photic environment that determines their behaviour. We identified rods, single cones and unequal double cones. Although it is a duplex retina, cones are preponderant and coloured oil droplets are present in their inner segments. As several colours in oil droplets are observed, it seems reasonable to conclude that several types of cones are present. Moreover, more cones per unit area are found in the central regions of the retina than in peripheral regions. A probable area centralis is observed. In the inner nuclear layer, two types of horizontal cells, and bipolar and amacrine cells can be recognised. Also, ganglion cells, characterised by prominent nuclei and nucleoli, vary in size and abundance among different regions in the retina. Comparisons are made with the retinae of other marine birds. The morphological characteristics of this retina indicate that Larus michahellis possesses: a good ability to discriminate colour; complex visual processing in the inner retina in order to mediate contrast and motion perception; and an elevated acuity in areas of high ganglion cell density.

The Structure of the Retina of the Eurasian Eagle-Owl and its Relation to Lifestyle

2017 ◽  
Vol 10 (1) ◽  
pp. 36-44 ◽  
Author(s):  
Belén Alix ◽  
Yolanda Segovia ◽  
Magdalena García
Keyword(s):  
Visual Processing ◽  
Ganglion Cells ◽  
Pigment Epithelium ◽  
Morphological Characteristics ◽  
Amacrine Cells ◽  
Light Sensitivity ◽  
Inner Nuclear Layer ◽  
Eagle Owl ◽  
The Relationship ◽  
Epithelium Cells

The retinal layers of birds are the same as those of other vertebrates; however, some variations exist in morphology, areas of visual acuity, and retinal vascularisation. Moreover, as a result of the relationship between environment, visual perception and behaviour, some variations are observed between diurnal and nocturnal birds. In this study, we have investigated the retina of the Eurasian Eagle-owl ( Bubo bubo hispanicus) by optical microscopy. The results indicate that the retina has features of both nocturnal and diurnal birds. The pigment epithelium cells have long prolongations filled with melanin granules. The rod is the dominant photoreceptor, but simple cones are abundant. Yellow and colourless oil droplets and paraboloid are present in the inner segment of cones. In the inner nuclear layer, the cell bodies of horizontal cells can easily be recognised by a large and pale cytoplasm. Bipolar cell perikarya are identified by their dark nuclei and the round and narrow cytoplasm. Amacrine cells, located in the inner border of the inner nuclear layer, have a round perikarya and lightly stained nuclei. Müller cells bodies, also located in this region, have an irregular shape. Finally, ganglion cells which are characterised by the prominent nuclei and nucleoli vary in size and abundance depending on different regions in the retina. The morphological characteristics of this retina indicate that B. b. hispanicus have a high light sensitivity, the capacity to discriminate colour, a complex visual processing in the inner retina in order to mediate contrast and motion and, possibly, an elevated acuity in areas of high photoreceptor and ganglion cell density.

A role for 5HT3 receptors in visual processing in the mammalian retina

1993 ◽  
Vol 10 (3) ◽  
pp. 511-522 ◽  
Author(s):  
William J. Brunken ◽  
Xiao-Tao Jin
Keyword(s):  
Visual Processing ◽  
Ganglion Cells ◽  
Cell Activity ◽  
Phosphatidyl Inositol ◽  
Amacrine Cells ◽  
Bipolar Cells ◽  
Reciprocal Effect ◽  
Mammalian Retina ◽  
Messenger System

AbstractWe investigated the role of 5HT3 receptors in the mammalian retina using electrophysiological techniques to monitor ganglion cell activity. Activation of 5HT3 receptors with the selective agonist 1-phenylbiguanide (PBG) increased the ON responses of ON-center ganglion cells, while decreasing the OFF responses of OFF-center cells. The application of a selective 5HT3 antagonist had a reciprocal effect, namely it reduced the center response in ON-center cells and concomitantly increased the center responses in OFF-center cells. Since putative serotoninergic amacrine cells in the retina are connected specifically to the rod bipolar cell, these agents most likely affect the rod bipolar terminal. These data, together with previous studies, suggest that both 5HT2 and 5HT3 receptors mediate an excitatory influence which serves to facilitate the output from rod bipolar cells, the former via a phosphatidyl inositol second-messenger system, and the latter via a direction channel.

scholarly journals A unique and evolutionarily conserved retinal interneuron relays rod and cone input to the inner plexiform layer

2020 ◽  
Author(s):  
Brent K. Young ◽  
Charu Ramakrishnan ◽  
Tushar Ganjawala ◽  
Yumei Li ◽  
Sangbae Kim ◽  
...  
Keyword(s):  
Visual Processing ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Building Blocks ◽  
Visual Signals ◽  
Inner Plexiform Layer ◽  
Inhibitory Neurotransmitter ◽  
Molecular Features ◽  
Evolutionarily Conserved

AbstractNeurons in the CNS are distinguished from each other by their morphology, the types of the neurotransmitter they release, their synaptic connections, and their genetic profiles. While attempting to characterize the retinal bipolar cell (BC) input to retinal ganglion cells (RGCs), we discovered a previously undescribed type of interneuron in mice and primates. This interneuron shares some morphological, physiological, and molecular features with traditional BCs, such as having dendrites that ramify in the outer plexiform layer (OPL) and axons that ramify in the inner plexiform layer (IPL) to relay visual signals from photoreceptors to inner retinal neurons. It also shares some features with amacrine cells, particularly Aii amacrine cells, such as their axonal morphology and possibly the release of the inhibitory neurotransmitter glycine, along with the expression of some amacrine cell specific markers. Thus, we unveil an unrecognized type of interneuron, which may play unique roles in vision.Significance StatementCell types are the building blocks upon which neural circuitry is based. In the retina, it is widely believed that all neuronal types have been identified. We describe a cell type, which we call the Campana cell, that does not fit into the conventional neuronal retina categories but is evolutionarily conserved. Unlike retinal bipolar cells, the Campana cell receives synaptic input from both rods and cones, has broad axonal ramifications, and may release an inhibitory neurotransmitter. Unlike retinal amacrine cells, the Campana cell receives direct photoreceptor input has bipolar-like ribbon synapses. With this discovery, we open the possibility for new forms of visual processing in the retina.

Amacrine cell-mediated input to bipolar cells: Variations on a common mechanistic theme

2012 ◽  
Vol 29 (1) ◽  
pp. 41-49 ◽  
Author(s):  
WILLIAM N. GRIMES
Keyword(s):  
Visual Processing ◽  
Amacrine Cell ◽  
Ganglion Cells ◽  
Amacrine Cells ◽  
Negative Influence ◽  
Bipolar Cells ◽  
Single Class ◽  
Anatomy And Physiology ◽  
Functional Context ◽  
The Brain

AbstractFeedback is a ubiquitous feature of neural circuits in the mammalian central nervous system (CNS). Analogous to pure electronic circuits, neuronal feedback provides either a positive or negative influence on the output of upstream components/neurons. Although the particulars (i.e., connectivity, physiological encoding/processing/signaling) of circuits in higher areas of the brain are often unclear, the inner retina proves an excellent model for studying both the anatomy and physiology of feedback circuits within the functional context of visual processing. Inner retinal feedback to bipolar cells is almost entirely mediated by a single class of interneurons, the amacrine cells. Although this might sound like a simple circuit arrangement with an equally simple function, anatomical, molecular, and functional evidence suggest that amacrine cells represent an extremely diverse class of CNS interneurons that contribute to a variety of retinal processes. In this review, I classify the amacrine cells according to their anatomical output synapses and target cell(s) (i.e., bipolar cells, ganglion cells, and/or amacrine cells) and discuss specifically our current understandings of amacrine cell-mediated feedback and output to bipolar cells on the synaptic, cellular, and circuit levels, while drawing connections to visual processing.

The harp seal, Pagophilus groenlandicus (Erxleben, 1777). VI. Structure of retina

1970 ◽  
Vol 48 (2) ◽  
pp. 367-370 ◽  
Author(s):  
A. R. Nagy ◽  
K. Ronald
Keyword(s):  
Ganglion Cells ◽  
Outer Nuclear Layer ◽  
Horizontal Cell ◽  
Single Layer ◽  
Amacrine Cells ◽  
Visual Sensitivity ◽  
Harp Seal ◽  
Pagophilus Groenlandicus ◽  
Area Centralis ◽  
Cell Processes

The retina of the harp seal (Pagophilus groenlandicus) was studied by means of the light microscope. Ganglion cells occupy a single layer. Thinly dispersed throughout this layer are giant ganglion cells. There is no area centralis. The inner nuclear layer consists of large horizontal cell processes with bipolar and amacrine cells between the horizontal cell processes. The outer nuclear layer is the thickest of all retinal layers. Its density is constant in the central and peripheral areas of the retina, similar to that found in the inner nuclear and ganglion layers. Only rod photoreceptors were found; therefore it is presumed that seals have no color vision. The tapetum covers an extensive area and is 32–34 cellular layers thick centrally, diminishing in thickness peripherally. The combination of tapetum and rod receptors makes possible excellent visual sensitivity to dim light.

scholarly journals A high frequency resonance in the responses of retinal ganglion cells to rapidly modulated stimuli: A computer model

2006 ◽  
Vol 23 (5) ◽  
pp. 779-794 ◽  
Author(s):  
J.A. MILLER ◽  
K.S. DENNING ◽  
J.S. GEORGE ◽  
D.W. MARSHAK ◽  
G.T. KENYON
Keyword(s):  
Computer Model ◽  
Visual Processing ◽  
High Frequency ◽  
Transfer Functions ◽  
Ganglion Cells ◽  
Amacrine Cells ◽  
Visual Signals ◽  
Phase Advance ◽  
Frequency Resonance ◽  
High Frequency Resonance

Brisk Y-type ganglion cells in the cat retina exhibit a high frequency resonance (HFR) in their responses to large, rapidly modulated stimuli. We used a computer model to test whether negative feedback mediated by axon-bearing amacrine cells onto ganglion cells could account for the experimentally observed properties of HFRs. Temporal modulation transfer functions (tMTFs) recorded from model ganglion cells exhibited HFR peaks whose amplitude, width, and locations were qualitatively consistent with experimental data. Moreover, the wide spatial distribution of axon-mediated feedback accounted for the observed increase in HFR amplitude with stimulus size. Model phase plots were qualitatively similar to those recorded from Y ganglion cells, including an anomalous phase advance that in our model coincided with the amplification of low-order harmonics that overlapped the HFR peak. When axon-mediated feedback in the model was directed primarily to bipolar cells, whose synaptic output was graded, or else when the model was replaced with a simple cascade of linear filters, it was possible to produce large HFR peaks but the region of anomalous phase advance was always eliminated, suggesting the critical involvement of strongly non-linear feedback loops. To investigate whether HFRs might contribute to visual processing, we simulated high frequency ocular tremor by rapidly modulating a naturalistic image. Visual signals riding on top of the imposed jitter conveyed an enhanced representation of large objects. We conclude that by amplifying responses to ocular tremor, HFRs may selectively enhance the processing of large image features.

scholarly journals Intrinsic properties and functional circuitry of the AII amacrine cell

2012 ◽  
Vol 29 (1) ◽  
pp. 51-60 ◽  
Author(s):  
JONATHAN B. DEMB ◽  
JOSHUA H. SINGER
Keyword(s):  
Visual Processing ◽  
Amacrine Cell ◽  
Ganglion Cells ◽  
Amacrine Cells ◽  
Cell Types ◽  
Bipolar Cells ◽  
Retinal Neuron ◽  
Motion Sensitivity ◽  
Network Properties ◽  
Aii Amacrine

AbstractAmacrine cells represent the most diverse class of retinal neuron, comprising dozens of distinct cell types. Each type exhibits a unique morphology and generates specific visual computations through its synapses with a subset of excitatory interneurons (bipolar cells), other amacrine cells, and output neurons (ganglion cells). Here, we review the intrinsic and network properties that underlie the function of the most common amacrine cell in the mammalian retina, the AII amacrine cell. The AII connects rod and cone photoreceptor pathways, forming an essential link in the circuit for rod-mediated (scotopic) vision. As such, the AII has become known as the rod–amacrine cell. We, however, now understand that AII function extends to cone-mediated (photopic) vision, and AII function in scotopic and photopic conditions utilizes the same underlying circuit: AIIs are electrically coupled to each other and to the terminals of some types of ON cone bipolar cells. The direction of signal flow, however, varies with illumination. Under photopic conditions, the AII network constitutes a crossover inhibition pathway that allows ON signals to inhibit OFF ganglion cells and contributes to motion sensitivity in certain ganglion cell types. We discuss how the AII’s combination of intrinsic and network properties accounts for its unique role in visual processing.

scholarly journals A retinal circuit for the suppressed-by-contrast receptive field of a polyaxonal amacrine cell

2020 ◽  
Vol 117 (17) ◽  
pp. 9577-9583 ◽  
Author(s):  
Yu Jia ◽  
Seunghoon Lee ◽  
Yehong Zhuo ◽  
Z. Jimmy Zhou
Keyword(s):  
Receptive Field ◽  
Visual Processing ◽  
Amacrine Cell ◽  
Ganglion Cells ◽  
Critical Role ◽  
Receptive Fields ◽  
Amacrine Cells ◽  
Large Field ◽  
Wide Field ◽  
Small Field

Amacrine cells are a diverse population of interneurons in the retina that play a critical role in extracting complex features of the visual world and shaping the receptive fields of retinal output neurons (ganglion cells). While much of the computational power of amacrine cells is believed to arise from the immense mutual interactions among amacrine cells themselves, the intricate circuitry and functions of amacrine–amacrine interactions are poorly understood in general. Here we report a specific interamacrine pathway from a small-field, glutamate–glycine dual-transmitter amacrine cell (vGluT3) to a wide-field polyaxonal amacrine cell (PAS4/5). Distal tips of vGluT3 cell dendrites made selective glycinergic (but not glutamatergic) synapses onto PAS4/5 dendrites to provide a center-inhibitory, surround-disinhibitory drive that helps PAS4/5 cells build a suppressed-by-contrast (sbc) receptive field, which is a unique and fundamental trigger feature previously found only in a small population of ganglion cells. The finding of this trigger feature in a circuit upstream to ganglion cells suggests that the sbc form of visual computation occurs more widely in the retina than previously believed and shapes visual processing in multiple downstream circuits in multiple ways. We also identified two different subpopulations of PAS4/5 cells based on their differential connectivity with vGluT3 cells and their distinct receptive-field and luminance-encoding characteristics. Moreover, our results revealed a form of crosstalk between small-field and large-field amacrine cell circuits, which provides a mechanism for feature-specific local (<150 µm) control of global (>1 mm) retinal activity.

scholarly journals Sophisticated Temporal Pattern Recognition in Retinal Ganglion Cells

2008 ◽  
Vol 99 (4) ◽  
pp. 1787-1798 ◽  
Author(s):  
Greg Schwartz ◽  
Michael J. Berry
Keyword(s):  
Pattern Recognition ◽  
Retinal Ganglion Cells ◽  
Visual Processing ◽  
Temporal Pattern ◽  
Ganglion Cells ◽  
Amacrine Cells ◽  
Ambystoma Tigrinum ◽  
Time Interval ◽  
Retinal Ganglion ◽  
Temporal Pattern Recognition

Pattern recognition is one of the most important tasks of the visual system, and uncovering the neural mechanisms underlying recognition phenomena has been a focus of researchers for decades. Surprisingly, at the earliest stages of vision, the retina is capable of highly sophisticated temporal pattern recognition. We stimulated the retina of tiger salamander ( Ambystoma tigrinum) with periodic dark flash sequences and found that retinal ganglion cells had a wide variety of different responses to a periodic flash sequence with many firing when a flash was omitted. The timing of the omitted stimulus response (OSR) depended on the period, with individual cells tracking the stimulus period down to increments of 5 ms. When flashes occurred earlier than expected, cells updated their expectation of the next flash time by as much as 50 ms. When flashes occurred later than expected, cells fired an OSR and reset their temporal expectation to the average time interval between flashes. Using pharmacology to investigate the retinal circuitry involved, we found that inhibitory transmission from amacrine cells was not required, but on bipolar cells were required. The results suggest a mechanism in which the intrinsic resonance of on bipolars leads to the OSR in ganglion cells. We discuss the implications of retinal pattern recognition on the neural code of the retina and visual processing in general.

scholarly journals An extracellular biochemical screen reveals that FLRTs and Unc5s mediate neuronal subtype recognition in the retina

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Jasper J Visser ◽  
Yolanda Cheng ◽  
Steven C Perry ◽  
Andrew Benjamin Chastain ◽  
Bayan Parsa ◽  
...  
Keyword(s):  
Visual Processing ◽  
Ganglion Cells ◽  
Expression Patterns ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Extracellular Proteins ◽  
Mouse Retina ◽  
Inner Plexiform Layer ◽  
Starburst Amacrine Cells

In the inner plexiform layer (IPL) of the mouse retina, ~70 neuronal subtypes organize their neurites into an intricate laminar structure that underlies visual processing. To find recognition proteins involved in lamination, we utilized microarray data from 13 subtypes to identify differentially-expressed extracellular proteins and performed a high-throughput biochemical screen. We identified ~50 previously-unknown receptor-ligand pairs, including new interactions among members of the FLRT and Unc5 families. These proteins show laminar-restricted IPL localization and induce attraction and/or repulsion of retinal neurites in culture, placing them in an ideal position to mediate laminar targeting. Consistent with a repulsive role in arbor lamination, we observed complementary expression patterns for one interaction pair, FLRT2-Unc5C, in vivo. Starburst amacrine cells and their synaptic partners, ON-OFF direction-selective ganglion cells, express FLRT2 and are repelled by Unc5C. These data suggest a single molecular mechanism may have been co-opted by synaptic partners to ensure joint laminar restriction.

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