scholarly journals Early development of eye and retina in lanternfish larvae

2007 ◽  
Vol 24 (3) ◽  
pp. 423-436 ◽  
Author(s):  
A. BOZZANO ◽  
P.M. PANKHURST ◽  
A. SABATÉS
Keyword(s):  
Visual Field ◽  
Surface Waters ◽  
Depth Distribution ◽  
Gradual Increase ◽  
Adult Life ◽  
Morphological Characteristics ◽  
Rod Photoreceptors ◽  
Scotopic Sensitivity ◽  
Concurrent Development ◽  
Binocular Visual Field

The morphological characteristics of the eyes and the retinae of lanternfish larvae ofLampanyctus crocodilus,Benthosema glaciale, andMyctophum punctatumwere analyzed in pre-flexion, flexion, and post-flexion stages. Pre-flexion larvae ofL. crocodilus, the species with the shallowest depth distribution, had spherical eyes located antero-laterally on a strongly laterally-compressed head, suggesting a forward binocular visual field.B. glacialeandM. punctatumlarvae live deeper in the water column and had eyes elongated in the dorsal-ventral plane. The eyes ofB. glacialewere prominent, projecting slightly outward from a laterally-compressed head, suggesting a strongly laterally-directed visual field.M. punctaumhad stalked elongated eyes projecting from a dorso-ventrally flattened head. The eyes can be freely rotated allowing lateral, anterior and dorsally-directed vision. A prominent choroidal gland was situated beneath the ventral portion of the eye inM. punctatumandB. glaciale, while a smaller gland was present in the dorsal and ventral portions of the eye ofL. crocodilus. In pre-flexion stage larvae, the retina of all three species was differentiated with numerous rod photoreceptors in the peripheral retinal areas and fewer cone photoreceptors mainly distributed in the central retina. This distribution suggests concomitant enhancement of scotopic sensitivity in the vertical visual plane and improved photopic acuity in the lateral and forward visual directions. The concurrent development of cones and rods, as observed in the pre-flexion stage of myctophid larvae, is consistent with meeting the special demands of visual planktivory in sub-surface waters. During larval development a gradual increase of ROS length was also accompanied by a progressive loss of cones that were almost totally absent in post-flexion larvae. This can be interpreted as an adaptive response to an impending deep mesopelagic adult life.

scholarly journals Estimating the Binocular Visual Field of Glaucoma Patients With an Adjustment for Ocular Dominance

2016 ◽  
Vol 57 (7) ◽  
pp. 3276 ◽  
Author(s):  
Masato Matsuura ◽  
Kazunori Hirasawa ◽  
Mieko Yanagisawa ◽  
Hiroyo Hirasawa ◽  
Hiroshi Murata ◽  
...  
Keyword(s):  
Visual Field ◽  
Ocular Dominance ◽  
Binocular Visual Field

Use of a Modified Binocular Visual Field to Assess Cyclodiplopia

Ophthalmology ◽  
1987 ◽  
Vol 94 (3) ◽  
pp. 231-234 ◽  
Author(s):  
C. Gail Summers ◽  
Jane D. Lavoie ◽  
Robert D. Letson
Keyword(s):  
Visual Field ◽  
Binocular Visual Field

Gender differences in cognition and perception may affect equine performance

2004 ◽  
Vol 32 ◽  
pp. 203-205
Author(s):  
J Murphy ◽  
T Waldmann ◽  
S Arkins
Keyword(s):  
Gender Differences ◽  
Visual Field ◽  
Depth Perception ◽  
Laboratory Animals ◽  
Small Laboratory ◽  
Diverse Range ◽  
3 Dimensional ◽  
General Preference ◽  
Show Jumping ◽  
Binocular Visual Field

Horses and their owners participate in an increasingly diverse range of equestrian pursuits including such activities as racing, show-jumping, endurance riding, carriage driving, dressage, hunting, pony club games, polo and leisure trekking. The majority of owners and riders within the disciplines of equitation appear to have a general preference toward using male horses as the chosen competition animal. Although not exclusively so, stallions and geldings are quite often physically bigger and stronger than fillies and mares and may enjoy some athletic advantage as a result. However, it is known from studies involving humans and small laboratory animals (mice and rats) that some gender differences in cognitive function may also affect performance where tasks involve 3-dimensional objects and elements of depth perception (Morris, Garrud, Rawlins, and O’ Keefe, 1982). The horse has laterally placed eyes (Budiansky, 1997 and Figure 1) and therefore a stereoscopic (binocular) visual field of approximately 65-70°.

Patterns of Binocular Visual Field Loss Derived from Large-Scale Patient Data from Glaucoma Clinics

Ophthalmology ◽  
2015 ◽  
Vol 122 (12) ◽  
pp. 2399-2406 ◽  
Author(s):  
Sen Hu ◽  
Nicholas D. Smith ◽  
Luke J. Saunders ◽  
David P. Crabb
Keyword(s):  
Visual Field ◽  
Large Scale ◽  
Visual Field Loss ◽  
Patient Data ◽  
Binocular Visual Field

scholarly journals Analysis of Binocular Visual Field Area on Blowout Fracture.

2000 ◽  
Vol 28 ◽  
pp. 199-203
Author(s):  
Chigusa Ohno ◽  
Kaoru Takano ◽  
Chizuko Tanaka ◽  
Masako Satou ◽  
Makoto Inatomi ◽  
...  
Keyword(s):  
Visual Field ◽  
Blowout Fracture ◽  
Field Area ◽  
Binocular Visual Field

scholarly journals Siphonophores from surface waters of the Colombian Pacific Ocean

2018 ◽  
Vol 99 (1) ◽  
pp. 67-80 ◽  
Author(s):  
Julian Uribe-Palomino ◽  
Raúl López ◽  
Mark J. Gibbons ◽  
Felipe Gusmão ◽  
Anthony J. Richardson
Keyword(s):  
Pacific Ocean ◽  
Surface Waters ◽  
Depth Distribution ◽  
Fish Larvae ◽  
Salinity Gradient ◽  
Abundant Species ◽  
Salinity Range ◽  
Fish Eggs ◽  
Positive Correlations ◽  
Colombian Pacific

Siphonophores are colonial hydrozoans that feed on zooplankton including fish larvae, and occur throughout the world's oceans from surface waters to ocean depths. Here we describe the composition of hyponeustonic siphonophores (0–3 m depth) from the tropical Colombian Pacific Ocean based on 131 plankton samples collected between June–October from 2001–2004. Samples were dominated by species of Calycophorae, with only three species of Physonectae identified, consistent with their deeper depth distribution. Muggiaea atlantica, Chelophyes contorta, Diphyes dispar, and Eudoxoides mitra were the most common of the 21 species identified. We found moderate structuring of the siphonophore community by the salinity gradient from inshore to offshore, and greater richness during the night because of diel vertical migration. Temperature did not play a significant role in structuring siphonophore communities, perhaps because of the narrow temperature range observed (3.5 °C). We extend the known temperature and salinity range of several species, including M. atlantica up to temperatures of 28.6 °C and salinities down to 24.7. Interestingly, only polygastric stages of M. atlantica were found, suggesting the reproductive stage of M. atlantica in tropical waters might be found in deeper waters. Chelophyes appendiculata was rare in our study and C. contorta was common, providing evidence they have a potential allopatric relationship, with C. contorta replacing C. appendiculata in warm water. Finally, we found siphonophore abundance was positively related to the abundance of copepods and fish eggs, with the top 13 most abundant species all having positive correlations, suggesting siphonophore abundances are tightly controlled by their food.

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