scholarly journals Monkeys use the rod-dense retinal region rather than the fovea to visually fixate small targets in scotopic vision

2018 ◽  
Author(s):  
Oleg Spivak ◽  
Peter Thier ◽  
Shabtai Barash
Keyword(s):  
Dark Adaptation ◽  
Scotopic Vision ◽  
Photopic Vision ◽  
Dark Background ◽  
Retinal Region ◽  
Dim Light ◽  
Small Targets ◽  
Visual Conditions

AbstractMonkeys appear to visually fixate targets in scotopic conditions. The function fixations fulfill in photopic vision, keeping the target’s image on the fovea, is nullified in scotopic vision, because the fovea, with its cones, is desensitized in dim light. Here we followed the hypothesis that a previously described retinal region, the locus of maximal rod density, functionally replaces the fovea; we found that with dark background, most of the fixations direct the fovea above the target, so that the target’s image appears to fall on the line connecting the fovea with the locus of maximal rod density. There is considerable trial-by-trial variation in the fixation positions along this line. On the whole, the closer the visual conditions are to full scotopic, the higher is this gaze upshift, indicating the closer does the target fall to the locus of maximal rod density. Mesopic background induces low mean upshift. Full (45-min) dark adaptation was essential to achieving high upshift values. There is no analogous photopic effect – 45-min ‘bright adaptation’ did not shift the locus of photopic fixation.

Study on the equivalent luminance of luminous fibers in photopic vision and scotopic vision

2017 ◽  
Vol 88 (10) ◽  
pp. 1157-1163 ◽  
Author(s):  
Yanhong Yan ◽  
Chengxia Liu ◽  
Xiaojun Ding
Keyword(s):  
Experimental Data ◽  
Rare Earth ◽  
Melt Spinning ◽  
Emission Spectra ◽  
Scotopic Vision ◽  
Photopic Vision ◽  
Earth Material ◽  
Long Afterglow ◽  
Polyamide Fiber ◽  
Spinning Process

Colored luminous fibers were prepared by a melt spinning process, adding colored pigments and long afterglow rare earth material into polyamide fiber. The colored luminous fibers had a variety of colors in photopic vision, and emitted colored light in mesopic vision and scotopic vision. Based on the experimental data of the emission spectra and the test luminance of the luminous fibers, the effect of the emissive colors of the luminous fibers on the equivalent luminance at different vision states was analyzed. The results showed that the effect of the emissive colors of white, red, yellow, and green luminous fibers on the equivalent luminance was not obvious in photopic and scotopic vision, but that of blue luminous fiber was obvious in photopic vision but not in scotopic vision.

scholarly journals Time-course of adaptations for electroretinography and pupillography

2021 ◽  
Vol 9 (4) ◽  
Author(s):  
Ken Asakawa
Keyword(s):  
Dark Adaptation ◽  
Time Course ◽  
Light Adaptation ◽  
Light Condition ◽  
Pupillary Response ◽  
Implicit Time ◽  
Scotopic Vision ◽  
Adaptation Time ◽  
Practical Applications ◽  
Rod Response

Cones are primarily involved in photopic vision and light adaptation. Rods are responsible for scotopic vision and dark adaptation. The typical time-courses of light and dark adaptations have been known for century. However, information regarding the minimal adaptation time for electroretinography (ERG) and pupillography would be helpful for practical applications and clinical efficiency. Therefore, we investigated the relationship between adaptation time and the parameters of ERG and pupillography. Forty-six eyes of 23 healthy women (mean age, 21.7 years) were enrolled. ERG and pupillography were tested for right and left eyes, respectively. ERG with a skin electrode was used to determine amplitude (µV) and implicit time (msec) by the records of rod-, flash-, cone-, and flicker-responses with white light (0.01–30 cd·s/m2). Infrared pupillography was used to record the pupillary response to 1-sec stimulation of red light (100 cd/m2). Cone- and flicker- (rod-, flash-, and pupil) responses were recorded after light (dark) adaptation at 1, 5, 10, 15, and 20 min. Amplitude was significantly different between 1 min and ≥5 or ≥10 min after adaptation in b-wave of cone- or rod-response, respectively. Implicit time differed significantly between 1 min and ≥5 min after adaptation with b-wave of cone- and rod-response. There were significant differences between 1 min and ≥10 or ≥5 min after dark adaptation in parameter of minimum pupil diameter or constriction rate, respectively. Consequently, light-adapted ERGs can be recorded, even in 5 min of light adaptation time without special light condition, whereas dark-adapted ERGs and pupillary response results can be obtained in 10 min or longer of dark adaptation time in complete darkness.

scholarly journals Dim-Light Sensitivity of Cells in the Awake Cat's Lateral Geniculate and Medial Interlaminar Nuclei: A Correlation With Behavior

2009 ◽  
Vol 102 (2) ◽  
pp. 841-852 ◽  
Author(s):  
Incheol Kang ◽  
Joseph G. Malpeli
Keyword(s):  
Temporal Frequency ◽  
Light Sensitivity ◽  
Scotopic Vision ◽  
Lateral Geniculate ◽  
Cell Class ◽  
Behavioral Sensitivity ◽  
Dim Light ◽  
Y Cells ◽  
Dorsal Lateral Geniculate ◽  
Contrast Thresholds

Contrast thresholds of cells in the dorsal lateral geniculate (LGNd) and medial interlaminar (MIN) nuclei of awake cats were measured for scotopic and mesopic vision with drifting sine gratings (1/8, 2, and 4 cycles/deg [cpd]; 4-Hz temporal frequency). Thresholds for mean firing rate (F0) and temporally modulated responses (F1) were derived with receiver-operating-characteristic analyses and compared with behavioral measures recently reported by Kang and colleagues. Behavioral sensitivity was predicted by the neural responses of the most sensitive combinations of cell class and response mode: Y-cell F1 responses for 1/8 cpd, X-cell F1 responses for 2 cpd, and Y-cell F0 responses for 4 cpd. All previous estimates of neural scotopic increment thresholds in animal models fell between Weber's law (proportional to retinal illuminance) and the deVries–Rose law (proportional to the square root of illuminance). However, psychophysical experiments suggest that under appropriate conditions human scotopic vision follows the deVries–Rose law. If behavioral sensitivity is assumed to be determined by the most sensitive class of cells, this discrepancy is resolved. Under scotopic conditions, off-center Y cells were the most sensitive and these followed the deVries–Rose law fairly closely. MIN Y cells were, on average, 0.25 log units more sensitive than LGNd Y cells under scotopic conditions, supporting a previous proposal that the MIN is a specialization of the carnivore for dim-light vision. We conclude that both physiologically and behaviorally, cat and human scotopic vision are fundamentally similar, including adherence to the deVries–Rose law for detection of Gabor functions.

scholarly journals Avian Binocularity and Adaptation to Nocturnal Environments: Genomic Insights from a Highly Derived Visual Phenotype

2019 ◽  
Vol 11 (8) ◽  
pp. 2244-2255 ◽  
Author(s):  
Rui Borges ◽  
João Fonseca ◽  
Cidália Gomes ◽  
Warren E Johnson ◽  
Stephen J O’Brien ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Eye Development ◽  
Positive Association ◽  
Barn Owl ◽  
Integrative Approach ◽  
Tyto Alba ◽  
Relaxed Selection ◽  
Scotopic Vision ◽  
Genomic Changes ◽  
Photopic Vision

Abstract Typical avian eyes are phenotypically engineered for photopic vision (daylight). In contrast, the highly derived eyes of the barn owl (Tyto alba) are adapted for scotopic vision (dim light). The dramatic modifications distinguishing barn owl eyes from other birds include: 1) shifts in frontal orientation to improve binocularity, 2) rod-dominated retina, and 3) enlarged corneas and lenses. Some of these features parallel mammalian eye patterns, which are hypothesized to have initially evolved in nocturnal environments. Here, we used an integrative approach combining phylogenomics and functional phenotypes of 211 eye-development genes across 48 avian genomes representing most avian orders, including the stem lineage of the scotopic-adapted barn owl. Overall, we identified 25 eye-development genes that coevolved under intensified or relaxed selection in the retina, lens, cornea, and optic nerves of the barn owl. The agtpbp1 gene, which is associated with the survival of photoreceptor populations, was pseudogenized in the barn owl genome. Our results further revealed that barn owl retinal genes responsible for the maintenance, proliferation, and differentiation of photoreceptors experienced an evolutionary relaxation. Signatures of relaxed selection were also observed in the lens and cornea morphology-associated genes, suggesting that adaptive evolution in these structures was essentially structural. Four eye-development genes (ephb1, phactr4, prph2, and rs1) evolved in positive association with the orbit convergence in birds and under relaxed selection in the barn owl lineage, likely contributing to an increased reliance on binocular vision in the barn owl. Moreover, we found evidence of coevolutionary interactions among genes that are expressed in the retina, lens, and optic nerve, suggesting synergetic adaptive events. Our study disentangles the genomic changes governing the binocularity and low-light perception adaptations of barn owls to nocturnal environments while revealing the molecular mechanisms contributing to the shift from the typical avian photopic vision to the more-novel scotopic-adapted eye.

scholarly journals The quantitative analysis of the photochemical bleaching of visual purple solutions in monochromatic light

1936 ◽  
Vol 156 (887) ◽  
pp. 158-170 ◽  
Keyword(s):  
Quantitative Analysis ◽  
Experimental Error ◽  
Wave Length ◽  
Monochromatic Light ◽  
Scotopic Vision ◽  
Monomolecular Reaction ◽  
The Subject ◽  
Dim Light ◽  
Kinetics Of ◽  
Adsorption Curve

In 1851 Muller noticed that under certain condition the rods of the frog's retina were coloured red. In 1876 Boll found that the retina bleached on exposure to light. This bleaching is now known to be due to the decolouration of a light sensitive pigment, visual purple or rhodopsin. It is generally accepted that this pigment place an important part in scotopic vision, i. e ., vision in dim light. Visual purple can be extracted from dark-adapted retinae by a number of reagents, including solutions of the salts and digitonin. The solutions of the pigments so obtained have been the subject of several spectrophotometric investigations. Trendelenburg in 1904 determined the adsorption curve of rabbits visual purple (maximum 507 mμ .) and also the relative efficiencies of different wave-lengths in bleaching the solutions. He established the similarity between the relative efficiencies and the human scotopic luminosity curve, as determined by him, for the same source of light. The adsorption curve has been determined by a number of other observers who find the maximum of adsorption of visual purple to be at about 500 for mammals, amphibia, etc., and at a variable wave-length for fish. Recently Hecht has studied the bleaching of visual purple solutions in white light. He showed that weak solutions bleach according to the Kinetics of a monomolecular reaction, the velocity constant being proportional to the intensity of the bleaching light and independent of the temperature within experimental error. In the present work the bleaching of visual purple in monochromatic light has been studied and, by means of absolute determinations of the light intensity, it has been found possible to apply fundamental photochemical principles to this reaction.

scholarly journals THE DARK ADAPTATION OF THE HUMAN EYE

1920 ◽  
Vol 2 (5) ◽  
pp. 499-517 ◽  
Author(s):  
Selig Hecht
Keyword(s):  
Dark Adaptation ◽  
Photochemical Reaction ◽  
Quantitative Data ◽  
Dark Reaction ◽  
Human Eye ◽  
Visual Threshold ◽  
Bimolecular Chemical Reaction ◽  
Dim Light ◽  
Visual Reception ◽  
Photosensitive Substance

During the dark adaptation of the human eye, its visual threshold decreases to a small fraction of its original value in the light. An analysis of the quantitative data describing this adaptation shows that it follows the course of a bimolecular chemical reaction. On the basis of these findings it is suggested that visual reception in dim light is conditioned by a reversible photochemical reaction involving a photosensitive substance and its two products of decomposition. Accordingly, dark adaptation depends on the course of the "dark" reaction during which the two products of decomposition reunite to synthesize the original photosensitive substance.

scholarly journals THE COURSE OF ROD DARK ADAPTATION AS INFLUENCED BY THE INTENSITY AND DURATION OF PRE-ADAPTATION TO LIGHT

1941 ◽  
Vol 24 (6) ◽  
pp. 735-751 ◽  
Author(s):  
Charles Haig
Keyword(s):  
Dark Adaptation ◽  
Light Adaptation ◽  
Prolonged Exposure ◽  
Bright Light ◽  
Time Axis ◽  
Reciprocity Law ◽  
Wide Range ◽  
Dim Light ◽  
The Right

An increase in the degree of light adaptation causes a decrease in the slope of the subsequent rod dark adaptation function and a displacement of the function to the right on the time axis. Over a wide range, these changes occur to the same extent whether the increase in the degree of light adaptation is produced by raising the intensity or by prolonging the exposure. Within these limits, the Bunsen-Roscoe reciprocity law applies to the intensity and duration of pre-exposure. Over a still wider range, dark adaptation has the same course following brief exposure to a bright light as it has following prolonged exposure to a dim light, provided the degree of light adaptation is the same in both instances (as indicated by identical initial dark adaptation thresholds).

scholarly journals Contrast Sensitivity of Cats and Humans in Scotopic and Mesopic Conditions

2009 ◽  
Vol 102 (2) ◽  
pp. 831-840 ◽  
Author(s):  
Incheol Kang ◽  
Rachel E. Reem ◽  
Amy L. Kaczmarowski ◽  
Joseph G. Malpeli
Keyword(s):  
Contrast Sensitivity ◽  
Temporal Frequency ◽  
Companion Paper ◽  
Behavioral Data ◽  
Scotopic Vision ◽  
Visual Systems ◽  
Spatial Frequencies ◽  
Dim Light ◽  
The Right ◽  
Central Fixation

Human contrast sensitivity in low scotopic conditions is regulated according to the deVries–Rose law. Previous cat behavioral data, as well as cat and mice electrophysiological data, have not confirmed this relationship. To resolve this discrepancy at the behavioral level, we compared sensitivity in dim light for cats and humans in parallel experiments using the same visual stimuli and similar behavioral paradigms. Both species had to detect Gabor functions (SD = 1.5°, spatial frequencies from 0 to 4 cpd, temporal frequency 4 Hz) presented 8° to the right or left of a central fixation point over an 8 log-unit range of adaptation levels spanning scotopic vision and extending well into the mesopic range. Cats had 0.74 log unit greater absolute sensitivity than that of humans for spatial frequencies ≤1/8 cpd. Cats had better contrast sensitivity overall for spatial frequencies <1/2 cpd, whereas humans were more sensitive for spatial frequencies above this. However, most of the cat's sensitivity advantage for low spatial frequencies could be accounted for by the greater light-concentrating abilities of its optics. Contrast sensitivity to 4 cpd was poor or absent in the scotopic range for both species. For both, scotopic increment thresholds were proportional to the square root of retinal illuminance, in accordance with the deVries–Rose law. Overall, cat and human visual systems appear to operate under very similar constraints for rod vision, including the regulation of contrast sensitivity across adaptation levels. A companion paper compares sensitivity of neurons in the lateral geniculate nucleus to these behavioral data.

The Importance of Vision in Agonistic Communication of the Crayfish Orconectes Rusticus. I: an Analysis of Bout Dynamics

Behaviour ◽  
1987 ◽  
Vol 103 (1-3) ◽  
pp. 83-107 ◽  
Author(s):  
Colleen Ann Bruski ◽  
D.W. Dunham
Keyword(s):  
Dark Adaptation ◽  
Compound Eye ◽  
Video Recording ◽  
Visual Sensitivity ◽  
Orconectes Rusticus ◽  
Energy Investment ◽  
Light Levels ◽  
Dim Light ◽  
Time And Energy ◽  
Visual Light

Abstract1. The importance of vision for efficient agonistic communication was investigated in the rusty crayfish, Orconectes rusticus, a species active both day and night. Agonistic bout dynamics were analyzed from isosexual pairs of males and females interacting under moderate (350 lux) and dim (11 lux) light levels, and in complete darkness (using infra-red video recording). Under dim light we determined the effect of visual light and dark adaptation on communication. 2. As light diminished, bouts became less frequent, but longer, and the crayfish invested more time and performed more acts when resolving bouts. Thus, communication efficiency was clearly lower in the dark than under moderate light, for both sexes. Males performed more acts than females overall, and were generally more aggressive than females. 3. The frequency of visually-mediated behaviours (e.g. Lunge, Follow) decreased in the absence oflight, while tactile behaviours (e.g. Antenna Tap, Chela Strike, Push) were performed more frequently. Males especially performed more highly aggressive tactile behaviours in the dark. It was shown that some behaviours previously considered to be visually mediated (e.g. Meral Spread) are also tactually or proprioceptively mediated, and some behaviours assumed to be tactually mediated (e.g. antennal movements) are probably also visually mediated. 4. Under dim light, crayfish with light-adapted eyes resolve bouts more efficiently in terms of time and energy investment than do dark-adapted animals. This is consistent with the effects of pigment migrations during dark adaptation in the crayfish superposition compound eye, which enhance visual sensitivity, but decrease acuity. We suggest that dark adaptation diminishes a crayfishes ability to deal with the subtleties of visual communication, but may well enhance its ability to detect predators.

The tapetum lucidum of gars (Lepisosteidae) and its role as a reflector

1974 ◽  
Vol 52 (12) ◽  
pp. 1523-1530 ◽  
Author(s):  
Richard T. Wang ◽  
J. A. Colin Nicol
Keyword(s):  
Optical Density ◽  
Light Absorption ◽  
Visual Pigment ◽  
Retinal Pigment ◽  
Scotopic Vision ◽  
Underwater Light ◽  
Tapetum Lucidum ◽  
Dim Light ◽  
Lake Waters

Eyes of four species of gars were studied, namely, alligator (Lepisosteus spatula Lacépède), spotted (L. oculatus (Winchell)), shortnose (L. platostomus Rafinesque), and longnqse (L. osseus (L.)). The retina is duplex, a yellow tapetum lucidum is present, rods and retinal pigment move, and the tapetum is uncovered in dim light. The visual pigment is a porphyropsin, λmax 523, and the optical density of the pigment in the retina is 0.22. Transmission through the retina is low at short wavelengths and rises steeply above 460 nm. Reflectance from the tapetum is diminished in the blue, and rises progressively at longer wavelengths to reach a maximum (70%) at about 650 nm. Underwater illumination was measured in waters where gars occur. In lake waters maximal transmissivity occurred at 375 nm and the transmission per meter ranged from 76 to 62%. In rivers and bays, transmission was maximal at long wavelengths, ≥600 nm, and the transmission per meter ranged from 37% to 0.001%; these waters sometimes were stained, and were fairly turbid to very muddy. The yellow tapetum is an efficient reflector of underwater light, the greater part of the energy of which occurs at long wavelengths. It is calculated that the tapetum increases light absorption in the retina by 30%. In muddy rivers inhabited by gars, scotopic vision involving the tapetum probably operates during the daytime at depths of 2 m or less.

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