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https://www.readbyqxmd.com/read/27185662/-electronic-eikonometer-measurement-tests-displayed-on-stereoscopic-screen
#1
C Bourdy, Y James
We propose the presentation on a stereoscopic screen of the electronic eikonometer tests intended for analysis and measurement of perceptual effects of binocular disparity. These tests, so-called "built-in magnification tests" are constructed according to the same principle as those of preceding eikonometers (disparity variation parameters being included in each test presentation, which allows, for test observation and measurements during the examination, the removing of any intermediate optical system). The images of these tests are presented separately to each eye, according to active or passive stereoscopic screen technology: (1) Ogle Spatial Test to measure aniseikonia; (2) Fixation Disparity test: binocular nonius; (3) retinal correspondence test evaluated by nonius horopter; (4) stereoscopic test using Julesz' random-dot stereograms (RDS)...
May 2016: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/26784710/myopia-control-with-bifocal-contact-lenses-a-randomized-clinical-trial
#2
RANDOMIZED CONTROLLED TRIAL
Thomas A Aller, Maria Liu, Christine F Wildsoet
PURPOSE: Most studies have reported only minimal reductions in myopia progression with bifocal or progressive multifocal spectacles, although somewhat larger, although mostly still clinically insignificant, effects have been reported in children with nearpoint esophoria and/or accommodative dysfunctions. The CONTROL study was a 1-year, prospective, randomized, clinical trial of bifocal contact lenses for control of myopia in children with eso fixation disparities at near. METHODS: Eighty-six myopic subjects, aged 8 to 18 years, were enrolled in the study after passing the screening examination...
April 2016: Optometry and Vision Science: Official Publication of the American Academy of Optometry
https://www.readbyqxmd.com/read/26562925/monocular-versus-binocular-calibrations-in-evaluating-fixation-disparity-with-a-video-based-eye-tracker
#3
Aiga Švede, Elīna Treija, Wolfgang Jaschinski, Gunta Krūmiņa
When measuring fixation disparity (an oculomotor vergence error), the question arises as to whether a monocular or binocular calibration is more precise and physiologically more appropriate. In monocular calibrations, a single eye fixates on a calibration target that is taken as having been projected onto the center of the fovea; the corresponding vergence state represents the heterophoria (the resting vergence position), which has no effect on the calibration procedure. In binocular calibrations, a vergence error may be present and may affect the subsequent measurement of the fixation disparity during binocular recordings...
2015: Perception
https://www.readbyqxmd.com/read/26327075/vergence-accommodation-and-apparent-viewing-distance-in-the-perception-of-depth-from-motion-parallax
#4
Mark Nawrot, Brian Connelly, Keith Stroyan
For fixed binocular disparity (BD), the relationship between viewing distance and relative depth is well known, the distance-square law. Similarly, perceived depth from motion parallax (MP) varies with viewing distance. Here, depth of a non-fixated object (d) varies with distance to the point of fixation (f), the retinal image velocity of the object (dθ), and velocity of the pursuit eye movement required to maintain fixation (dα). The relationship, termed the motion/pursuit ratio, is: d = dθ/dα * f . Here we investigated how the cues of vergence and accommodation contribute to apparent viewing distance in MP by assessing perceived depth magnitude...
2015: Journal of Vision
https://www.readbyqxmd.com/read/26326518/decision-related-activity-in-v2-for-a-fine-disparity-discrimination-task
#5
Stéphane Clery, Bruce Cumming, Hendrikje Nienborg
The stereoscopic depth of a target can be evaluated relative to the fixation plane (absolute disparity) or relative to a background (relative disparity). Fine disparity discrimination is thought to rely on relative disparity judgments (Prince et al., 2000). V2 neurons are the first in the visual processing hierarchy to show selectivity for relative disparity (Thomas et al., 2002), and have previously been found to have decision-related activity for coarse disparity discrimination tasks (Nienborg and Cumming, 2006, 2009)...
2015: Journal of Vision
https://www.readbyqxmd.com/read/26326484/cues-for-accommodation-and-vergence-in-infancy-and-early-childhood
#6
T Rowan Candy, Erin Babinsky, Tawna Roberts, Vivian Manh, Eric Seemiller, Yifei Wu, Don Lyon
PURPOSE: Focused binocular fixation on a target relies on a combination of accommodation and vergence oculomotor responses. These require recalibration during early development, as a result of changes in refractive error and increases in inter-pupillary distance (IPD). This study tracked the roles of blur and disparity cues in these motor responses during this period. METHODS: 103 infants were followed from 3 months until 3 years of age. Their accommodation and vergence responses to a movie with naturalistic spatial amplitude spectra were recorded simultaneously using eccentric photorefraction and Purkinje image tracking (PowerRefractor, MCS)...
2015: Journal of Vision
https://www.readbyqxmd.com/read/26325931/mapping-eye-movements-in-3d-preferential-fixation-of-surface-curvature-minima-during-object-recognition-in-stereo-viewing
#7
Charles Leek, Stephen Johnston, Filipe Cristino
The recognition of 3D object shape is a fundamental issue in vision science. Although our knowledge has advanced considerably, most prior studies have been restricted to 2D stimulus presentation that ignores stereo disparity. In previous work we have shown how analyses of eye movement patterns can be used to elucidate the kinds of shape information that support the recognition of multi-part 3D objects (e.g., Davitt et al. , JEP: HPP, 2014, 40, 451-456). Here we extend that work using a novel technique for the 3D mapping, and analyses, of eye movement patterns under conditions of stereo viewing...
2015: Journal of Vision
https://www.readbyqxmd.com/read/26311782/computation-of-object-size-in-visual-cortical-area-v4-as-a-neural-basis-for-size-constancy
#8
Shingo Tanaka, Ichiro Fujita
UNLABELLED: Even when we view an object from different distances, so that the size of its projection onto the retina varies, we perceive its size to be relatively unchanged. In this perceptual phenomenon known as size constancy, the brain uses both distance and retinal image size to estimate the size of an object. Given that binocular disparity, the small positional difference between the retinal images in the two eyes, is a powerful visual cue for distance, we examined how it affects neuronal tuning to retinal image size in visual cortical area V4 of macaque monkeys...
August 26, 2015: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/26289634/is-pelvic-incidence-a-constant-as-everyone-knows-changes-of-pelvic-incidence-in-surgically-corrected-adult-sagittal-deformity
#9
Jung-Hee Lee, Ki-Ho Na, Jin-Hyok Kim, Ho-Yeon Jeong, Dong-Gune Chang
PURPOSE: Previous investigations have recognized the critical role of pelvic parameters in the setting of a fixed sagittal deformity. Pelvic incidence (PI) is a constant, as everyone knows. However, PI might change reciprocally because of increased shear force on the sacroiliac joint, following surgical correction of fixed lumbar lordosis (LL). The disparity in PI after surgery according to the surgical method, and its impact on final follow-up, has not been reported. This study was undertaken to analyze the disparity of PI before and after surgery, and to evaluate its impact on final sagittal alignment in surgically corrected lordosis when there is immediate postoperative normal alignment following correction of adult sagittal deformity...
August 20, 2015: European Spine Journal
https://www.readbyqxmd.com/read/26176876/crouzon-syndrome-relationship-of-eye-movements-to-pattern-strabismus
#10
Avery H Weiss, John P Kelly, Richard A Hopper, James O Phillips
PURPOSE: To characterize conjugate eye movements in Crouzon syndrome (CS) patients with and without strabismus. METHODS: Smooth pursuit, saccades, horizontal optokinetic nystagmus (OKN), and horizontal vestibulo-ocular reflex (VOR) were recorded using binocular video-oculography (VOG) in 10 children with CS (5 orthotropic, 5 strabismic) and 12 age-matched controls. Hess-Lancaster plots were generated from Orbit 1.8 using rectus muscle pulley locations from computed tomography imaging...
July 2015: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/26174232/the-combined-use-of-unilateral-pedicle-screw-and-contralateral-facet-joint-screw-fixation-in-transforaminal-lumbar-interbody-fusion
#11
RANDOMIZED CONTROLLED TRIAL
Yuanwu Cao, Zixian Chen, Chun Jiang, Shengcheng Wan, Xiaoxing Jiang, Zhenzhou Feng
PURPOSE: This paper is to evaluate the efficacy and safety of transforaminal lumbar interbody fusion (TLIF) using unilateral pedicle screws along with contralateral translaminar facet joint screw (UPS+TFS) fixation in comparison with the method using bilateral pedicle screws fixation (BPS) in degenerative lumbar diseases. METHODS: Forty patients with single-level lumbar diseases were divided into two groups randomly. One group was treated by TLIF with BPS fixation while the other group was treated by the new technique with UPS+TFS fixation...
November 2015: European Spine Journal
https://www.readbyqxmd.com/read/26170675/the-reduction-of-volume-and-fiber-bundle-connections-in-the-hippocampus-of-egr3-transgenic-schizophrenia-rats
#12
Ensen Ma, Tianbin Song, Hui Zhang, Jie Lu, Liwen Wang, Qichao Zhao, Runcai Guo, Miao Li, Guolin Ma, Guangming Lu, Kefeng Li
BACKGROUND AND OBJECTIVE: There is a growing consensus that schizophrenia is ultimately caused by abnormal communication between spatially disparate brain structures. White matter fasciculi represent the primary infrastructure for long distance communication in the brain. In this study, we aimed to investigate the white matter connection in schizophrenia susceptible brain regions of early growth response factor 3 (EGR3) expressing rats. METHODS: A rat model of schizophrenia was created by the transfection of the EGR3 gene into rat hippocampus...
2015: Neuropsychiatric Disease and Treatment
https://www.readbyqxmd.com/read/26091221/acute-operative-management-of-humeral-shaft-fractures-analysis-of-the-national-trauma-data-bank
#13
Paul E Matuszewski, Tae Won Kim, Andre N Gay, Samir Mehta
Advances in surgical techniques have increased the role of early surgical intervention for isolated diaphyseal humerus fractures. The goal of this study was to investigate the following: (1) the current trend of operative treatment; (2) factors that affect surgical treatment; and (3) the effect of surgical fixation on length of stay, complication rates, and hospital disposition. The National Trauma Data Bank from 2004 to 2006 was analyzed. All patients with multiple injuries that included closed humeral shaft fractures and all patients with isolated humeral shaft fractures were included...
June 2015: Orthopedics
https://www.readbyqxmd.com/read/25929779/socioeconomic-factors-are-associated-with-trends-in-treatment-of-pediatric-femoral-shaft-fractures-and-subsequent-implant-removal-in-new-york-state
#14
Emily Dodwell, James Wright, Roger Widmann, Flo Edobor-Osula, Ting-Jung Pan, Stephen Lyman
BACKGROUND: Disparities exist in access to outpatient pediatric orthopaedic care. The purpose of this study was to assess whether disparities also exist in elective pediatric orthopaedic surgical procedures such as implant removal, and to determine which demographic and socioeconomic factors may be associated with differences in treatment. METHODS: Children aged 7 to 18 inclusive who sustained femoral shaft fractures between the years 1997 and 2010 were identified in the New York State SPARCS database...
July 2016: Journal of Pediatric Orthopedics
https://www.readbyqxmd.com/read/25926470/functional-architecture-for-disparity-in-macaque-inferior-temporal-cortex-and-its-relationship-to-the-architecture-for-faces-color-scenes-and-visual-field
#15
Bram-Ernst Verhoef, Kaitlin S Bohon, Bevil R Conway
Binocular disparity is a powerful depth cue for object perception. The computations for object vision culminate in inferior temporal cortex (IT), but the functional organization for disparity in IT is unknown. Here we addressed this question by measuring fMRI responses in alert monkeys to stimuli that appeared in front of (near), behind (far), or at the fixation plane. We discovered three regions that showed preferential responses for near and far stimuli, relative to zero-disparity stimuli at the fixation plane...
April 29, 2015: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/25896581/-whiplash-and-oculomotor-disorders-the-pet-peeve-of-the-experts%C3%A2
#16
C Speeg-Schatz, S Gottenkiene, J S Raul, A Sauer
Whiplash is a lay term combining all the complications of a cervical sprain or distortion associated with an extension. It may lead to cervical or back pain, but patients may also complain about functional visual impairment. These visual complaints: fixation disparity, heterophoria or convergence insufficiency, are frequently neglected and difficult to quantitate and treat. Establishing the relationship between the indirect cervical trauma and the visual signs may be challenging for the medical-legal expert and must include consideration of the previous oculomotor status of the patient...
May 2015: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/25891121/accommodation-and-pupil-responses-to-random-dot-stereograms
#17
Rajaraman Suryakumar, Robert Allison
We investigated the dynamics of accommodative and pupillary responses to random-dot stereograms presented in crossed and uncrossed disparity in six visually normal young adult subjects (mean age=25.8±3.1 years). Accommodation and pupil measures were monitored monocularly with a custom built photorefraction system while subjects fixated at the center of a random-dot stereogram. On each trial, the stereogram initially depicted a flat plane and then changed to depict a sinusoidal corrugation in depth while fixation remained constant...
January 2016: Journal of Optometry
https://www.readbyqxmd.com/read/25876848/the-uptake-and-excretion-of-partially-oxidized-sulfur-expands-the-repertoire-of-energy-resources-metabolized-by-hydrothermal-vent-symbioses
#18
R A Beinart, A Gartman, J G Sanders, G W Luther, P R Girguis
Symbiotic associations between animals and chemoautotrophic bacteria crowd around hydrothermal vents. In these associations, symbiotic bacteria use chemical reductants from venting fluid for the energy to support autotrophy, providing primary nutrition for the host. At vents along the Eastern Lau Spreading Center, the partially oxidized sulfur compounds (POSCs) thiosulfate and polysulfide have been detected in and around animal communities but away from venting fluid. The use of POSCs for autotrophy, as an alternative to the chemical substrates in venting fluid, could mitigate competition in these communities...
May 7, 2015: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/25875685/perceptual-motor-computational-model-of-anomalous-binocular-correspondence
#19
Clifton Schor
PURPOSE: A head-centric disparity model of anomalous binocular correspondence (ABC) in strabismus provides a framework that captures several associated perceptual-motor characteristics that are unexplained by the retino-centric model (anomalous retinal correspondence) of Von Graefe and Burian. The head-centric model elaborates on the anomalous-projection model of Verhoeff and Brock, originally described by Wells, late in the 18th century, which proposes that three-dimensional space perception is based on information obtained separately from the two eyes in ABC, without binocular retinal correspondence...
May 2015: Optometry and Vision Science: Official Publication of the American Academy of Optometry
https://www.readbyqxmd.com/read/25839421/a-comparative-analysis-of-vertical-and-horizontal-fixation-disparity-in-sentence-reading
#20
S Jainta, H I Blythe, M Nikolova, M O Jones, S P Liversedge
Humans have two, frontally placed eyes and during reading oculomotor and sensory processes are needed to combine the two inputs into a unified percept of the text. Generally, slight vergence errors, i.e., fixation disparities, occur but do not cause double vision since disparate retinal inputs fall into Panum's fusional area, that is, a range of disparity wherein sensory fusion of the two retinal images is achieved. In this study, we report benchmark data with respect to the mean magnitude and range of vertical compared to horizontal fixation disparities for natural reading...
May 2015: Vision Research
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