Overrepresentation of the central visual field in the superior colliculus of the pigmented and albino ferret

1996 ◽  
Vol 13 (4) ◽  
pp. 627-638 ◽  
Author(s):  
C. Quevedo ◽  
K.-P. Hoffmann ◽  
R. Husemann ◽  
C. Distler
Keyword(s):  
Visual Field ◽  
Superior Colliculus ◽  
Ganglion Cell ◽  
Cell Density ◽  
Visual Space ◽  
Peripheral Retina ◽  
Magnification Factor ◽  
Central Visual Field ◽  
Visual Streak ◽  
Area Centralis

AbstractWe have examined the retinotopy in the superior colliculus of pigmented and albino ferrets using both anatomical and electrophysiological methods. While the distribution of contralaterally projecting retinotectal ganglion cells is characterized by the presence of an area centralis superimposed on a visual streak in both strains, the ipsilateral projection from temporal hemiretina is strongly reduced in albinos. In spite of the significantly altered retinotectal projection pattern, the collicular visual field map in the albino ferret reveals the same characteristics as in the pigmented animal with a strongly enlarged representation of the center of visual space. An areal comparison between retinotectal ganglion cell distribution and collicular areal magnification shows that the increase in areal magnification factor between the periphery and the representation of the central visual hemifield exceeds the corresponding increase in retinal ganglion cell density between peripheral retina and area centralis by a factor of three in pigmented and a factor of four in albino ferrets. The areal magnification factor of the representation of the retinal visual streak does not exceed the increase in retinotectal ganglion cell density. Thus, our results suggest that the representation of visual space in the superior colliculus of albino and pigmented ferrets does not simply follow the retinotectal ganglion cell density, but that there is an enhanced representation of the frontal central visual field. The possibility is discussed that the collicular visual field map may be determined either by both retinotectal and corticotectal projections or by the colliculus' intrinsic structure.

The retinal ganglion cell distribution and the representation of the visual field in area 17 of the owl monkey, Aotus trivirgatus

1993 ◽  
Vol 10 (5) ◽  
pp. 887-897 ◽  
Author(s):  
L. C. L. Silveira ◽  
V. H. Perry ◽  
E. S. Yamada
Keyword(s):  
Visual Cortex ◽  
Visual Field ◽  
Ganglion Cell ◽  
Cell Density ◽  
Ganglion Cells ◽  
Amacrine Cells ◽  
Temporal Region ◽  
Cell Distribution ◽  
Area 17 ◽  
Displaced Amacrine Cells

AbstractThe distribution of ganglion cells and displaced amacrine cells was determined in whole-mounted Aotus retinae. In contrast to diurnal simians, Aotus has only a rudimentary fovea. Ganglion cell density decreases towards the periphery at approximately the same rate along all meridians, but is 1.2–1.8 times higher in the nasal periphery when compared to temporal region at the same eccentricities. The total number of ganglion cells varied from 421,500 to 508,700. Ganglion cell density peaked at 15,000/mm2 at 0.25 mm dorsal to the fovea. The displaced amacrine cells have a shallow density gradient, their peak density in the central region is about 1500–2000/mm2 and their total number varied from 315,900 to 482,800. Comparison between ganglion cell density and areal cortical magnification factor for the primary visual cortex, area 17, shows that there is not a simple proportional representation of the ganglion cell distribution. There is an overrepresentation of the central 10 deg of the visual field in the visual cortex. The present results for Aotus and the results of a similar analysis of data from other primates indicate that the overrepresentation of the central visual field is a general feature of the visual system of primates.

The morphology and topographic distribution of substance- P-like immunoreactive amacrine cells in the cat retina

1989 ◽  
Vol 237 (1289) ◽  
pp. 471-488 ◽  
Keyword(s):  
Substance P ◽  
Ganglion Cell ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Maximum Density ◽  
Peripheral Retina ◽  
Inner Plexiform Layer ◽  
Cat Retina ◽  
Area Centralis ◽  
Topographic Distribution

In cat retinal wholemounts, substance-P-like immunoreactivity (SP-IR) was localized in a distinct population of amacrines whose cell bodies were normally placed in the ganglion cell layer. Although displaced amacrines accounted for 80-95% of the SP-IR amacrines in peripheral retina, this proportion decreased considerably within the area centralis, accounting for 50-80% of the labelled cells at maximum density. The SP-IR cells in both the inner nuclear and ganglion cell layers gave rise to well-defined varicose dendrites of uniform appearance that stratified around 60% depth (S3/S4) of the inner plexiform layer. In addition, sparse fine dendrites in stratum 1 (S1) could sometimes be traced to inner nuclear cells and occasionally to displaced amacrines. The combined SP-IR cell density ranged from less than 50 cells mm -2 in the far periphery to more than 500 cells mm -2 in the area centralis; the maximum density showed little individual variation despite wide differences in the proportion of displaced cells. The 39000 SP-IR amacrines in a mapped retina had a triangular topographic distribution, with intermediate isodensity lines extending vertically in superior retina and horizontally along both arms of the visual streak. Colocalization experiments established that all SP-IR cells in cat retina showed GABA-like immunoreactivity, and that the SP-IR amacrines were quite distinct from the cholinergic amacrines identified by choline acetyltransferase immunohistochemistry.

Cortical magnification factor and the ganglion cell density of the primate retina

Nature ◽  
1989 ◽  
Vol 341 (6243) ◽  
pp. 643-646 ◽  
Author(s):  
Heinz Wässle ◽  
Ulrike Grünert ◽  
Jürgen Röhrenbeck ◽  
Brian B. Boycott
Keyword(s):  
Ganglion Cell ◽  
Cell Density ◽  
Magnification Factor ◽  
Cortical Magnification ◽  
Cortical Magnification Factor

Topographic analysis of the ganglion cell layer in the retina of the four-eyed fish Anableps anableps

2006 ◽  
Vol 23 (6) ◽  
pp. 879-886 ◽  
Author(s):  
FRANCISCO GILBERTO OLIVEIRA ◽  
JOÃO PAULO COIMBRA ◽  
ELIZABETH SUMI YAMADA ◽  
LUCIANO FOGAÇA DE ASSIS MONTAG ◽  
FRANCYLLENA L. NASCIMENTO ◽  
...  
Keyword(s):  
Visual Field ◽  
Ganglion Cell ◽  
Ganglion Cell Layer ◽  
Ganglion Cells ◽  
Cell Layer ◽  
Behavioral Strategies ◽  
Topographic Analysis ◽  
Contour Maps ◽  
Visual Streak ◽  
Peak Cell Density

Fish of the genus Anableps (Anablepidae, Cyprinodontiformes) have eyes that are adapted for simultaneous aerial and aquatic vision. In this study we investigate some of the corresponding retinal specializations of the adult Anableps anableps eye using retinal transverse sections and wholemounts. The linear dimensions of the retina were found to be asymmetric with a greater representation of the dorsal compared to the ventral visual field. The total number of neurons in the ganglion cell layer of the ventral hemiretina was on average 3.6 times greater than the values obtained in the dorsal hemiretina. Isodensity contour maps revealed a prominent horizontal visual streak in the ventral hemiretina with an average peak cell density of 18,286 cells/mm2. A second less-well-developed horizontal visual streak was also observed in the dorsal hemiretina. A sub-population of large cells with soma areas between 74 and 188 μm2 was identified and found to be distributed evenly across both hemiretinas. Together, these results show that the sampling gain of the ventral retina is significantly greater than the dorsal segment, that retinal specializations important for mediating acute vision are present in the parts of the visual field immediately above and below the surface of the water, and that visual functions related with the large ganglion cells require more even sampling across the visual field. The relevance of these retinal specializations to the feeding and other behavioral strategies adopted by Anableps is discussed.

scholarly journals Linkage between retinal ganglion cell density and the nonuniform spatial integration across the visual field

2019 ◽  
Vol 116 (9) ◽  
pp. 3827-3836 ◽  
Author(s):  
MiYoung Kwon ◽  
Rong Liu
Keyword(s):  
Object Recognition ◽  
Visual Field ◽  
Ganglion Cell ◽  
Cell Density ◽  
Visual Information ◽  
Computational Models ◽  
Target Location ◽  
Fixed Number ◽  
Retinal Ganglion ◽  
Spatial Integration

The ability to integrate visual information over space is a fundamental component of human pattern vision. Regardless of whether it is for detecting luminance contrast or for recognizing objects in a cluttered scene, the position of the target in the visual field governs the size of a window within which visual information is integrated. Here we analyze the relationship between the topographic distribution of ganglion cell density and the nonuniform spatial integration across the visual field. The extent of spatial integration for luminance detection (Ricco’s area) and object recognition (crowding zone) are measured at various target locations. The number of retinal ganglion cells (RGCs) underlying Ricco’s area or crowding zone is estimated by computing the product of Ricco’s area (or crowding zone) and RGC density for a given target location. We find a quantitative agreement between the behavioral data and the RGC density: The variation in the sampling density of RGCs across the human retina is closely matched to the variation in the extent of spatial integration required for either luminance detection or object recognition. Our empirical data combined with the simulation results of computational models suggest that a fixed number of RGCs subserves spatial integration of visual input, independent of the visual-field location.

Distribution and size of ganglion cells in the retinae of large Amazon rodents

1989 ◽  
Vol 2 (3) ◽  
pp. 221-235 ◽  
Author(s):  
L. C. L. Silveira ◽  
C. W. Picanço-Diniz ◽  
E. Oswaldo-Cruz
Keyword(s):  
Ganglion Cell ◽  
Cell Size ◽  
Cell Density ◽  
Ganglion Cells ◽  
Cell Number ◽  
Retinal Ganglion ◽  
Size Spectra ◽  
Topographical Distribution ◽  
Visual Streak ◽  
Soma Size

AbstractThe topographical distribution of density and soma size of the retinal ganglion cells were studied in three species of hystricomorph rodents. Flat-mounted retinae were stained by the Nissl method and the ganglion cells counted on a matrix covering the whole retinae. Soma size was determined for samples at different retinal regions. The agouti, a diurnal rodent, shows a well-developed visual streak, reaching a peak density of 6250 ganglion cells/mm2. The total number of ganglion cells ranged from 477, 427–548, 205 in eight retinae. The ganglion-cell-size histogram of the visual streak region exhibits a marked shift towards smaller values when compared to retinal periphery. Upper and lower regions differ in both cell density and cell size. The crepuscular capybara shows a less-developed visual streak with a peak ganglion cell density of 2250/mm2. The shift towards small-sized cells in the visual streak is less marked. Total ganglion cell population is 368,840. In the nocturnal paca, the upper half of the fundus oculi includes a tapetum lucidum. The retina of this species shows the least-developed visual streak of this group, with the lowest peak ganglion cell density reaching 925/mm2. The total ganglion cell number (230,804) is also smaller than in the two other species. Soma-size spectra of this species are characterized by the presence, in the lower hemi-retina, of very large perikarya comparable in size to the cat's alpha ganglion cells.

Relative Localization of Auditory and Visual Events Presented in Peripheral Visual Field

2014 ◽  
Vol 27 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Ryota Miyauchi ◽  
Dea-Gee Kang ◽  
Yukio Iwaya ◽  
Yôiti Suzuki
Keyword(s):  
Visual Field ◽  
Spatial Information ◽  
Visual Space ◽  
Peripheral Visual Field ◽  
Central Visual Field ◽  
Relative Localization ◽  
Visual Events ◽  
Pointing Task ◽  
Flashing Light ◽  
The Brain

The brain apparently remaps the perceived locations of simultaneous auditory and visual events into a unified audio-visual space to integrate and/or compare multisensory inputs. However, there is little qualitative or quantitative data on how simultaneous auditory and visual events are located in the peripheral visual field (i.e., outside a few degrees of the fovea). We presented a sound burst and a flashing light simultaneously not only in the central visual field but also in the peripheral visual field and measured the relative perceived locations of the sound and flash. The results revealed that the sound and flash were perceptually located at the same location when the sound was presented at a 5° periphery of the flash, even when the participants’ eyes were fixed. Measurements of the unisensory locations of each sound and flash in a pointing task demonstrated that the perceived location of the sound shifted toward the front, while the perceived location of the flash shifted toward the periphery. As a result, the discrepancy between the perceptual location of the sound and the flash was around 4°. This suggests that the brain maps the unisensory locations of auditory and visual events into a unified audio-visual space, enabling it to generate unisensory spatial information about the events.

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