Abstract：
:Recent evidence suggests a double dissociation of size and spacing limit on letter recognition-it is limited by size in the fovea and critical spacing in the normal periphery. Here, we evaluated whether size or spacing limits letter recognition in people with age-related macular degeneration (AMD) who must use their peripheral vision. We measured the size threshold for recognizing lowercase letters presented alone, or flanked by two letters at various center-to-center nominal letter spacings (multiples of letter size) for 11 observers with AMD. For comparison, similar measurements were obtained at 5° and 10° eccentricity in the nasal and lower visual fields in three older adults with normal vision. Single-letter size thresholds were worse for observers with AMD than at comparable retinal locations in the normal periphery. For flanked letters, size threshold improved with larger nominal spacing up to the critical spacing, beyond which size threshold was unaffected by the flankers. Seven AMD observers had a nominal critical spacing between 1.25× and 1.80×, values close to those in the normal fovea, suggesting that their letter recognition is size-limited; two had a nominal critical spacing of 3-4×, values close to those in the normal periphery, implying that their letter recognition is limited by spacing; and another two had a nominal critical spacing of ∼2.3×, implying that their letter recognition is limited by both size and spacing. The wide range of nominal critical spacings observed in our AMD observers may reflect the degree of completeness of their adaptation process to vision loss.
journal_name
Vision Resjournal_title
Vision researchauthors
Chung STdoi
10.1016/j.visres.2014.06.015subject
Has Abstractpub_date
2014-08-01 00:00:00pages
167-76eissn
0042-6989issn
1878-5646pii
S0042-6989(14)00151-5journal_volume
101pub_type
杂志文章相关文献
VISION RESEARCH文献大全abstract：:To describe small scotomas in visual field examinations several statistical models are proposed and applied to the evaluation of angioscotoma in 13 ophthalmologically normal subjects. A special perimetric grid is used where thresholds can be estimated along a line of narrow-spaced test points which crosses the predict...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(98)00294-6
更新日期：1999-05-01 00:00:00
abstract：:The retinae of two species of teleosts, the rippled blenny Istiblennius edentulus and the blue tusk fish Choerodon albigena are examined in wholemount. The retinal topography of Nissl-stained cells within the ganglion cell layer in each species reveals a temporal (4.32 x 10(4) cells per mm2) and a nasal (3.83 x 10(4) ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(89)90089-8
更新日期：1989-01-01 00:00:00
abstract：:The mechanisms underlying the parsing of a spatial distribution of velocity vectors into two adjacent (spatially segregated) or overlapping (transparent) motion surfaces were examined using random dot kinematograms. Parsing might occur using either of two principles. Surfaces might be defined on the basis of similarit...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(00)00013-4
更新日期：2000-01-01 00:00:00
abstract：:We consider how local motion signals are combined to represent the movements of spatially extensive objects. A series of band-pass target dots, whose collective motion defined a moving contour, was positioned within a field of randomly moving noise dots. The visibility of the contours did not depend on the direction o...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(03)00329-8
更新日期：2003-09-01 00:00:00
abstract：:The purpose of this study was to demonstrate the effect of human magnocellular (M)-pathway disruption on global motion perception. Coherence thresholds for global motion direction discrimination in random dot patterns were determined at slow and moderate dot speeds: (1) after adaptation to full-field sinusoidal flicke...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2004.06.003
更新日期：2004-01-01 00:00:00
abstract：:Binocular sensory fusion which was previously thought to have a maximum spatial extent at the fovea of 1 deg is at least 600% larger when stimulated by low spatial frequency (coarse) detail. This upper limit for sensory fusion has a constant phase disparity limit of 90 deg which corresponds to the monocular Rayleigh c...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(84)90207-4
更新日期：1984-01-01 00:00:00
abstract：:In a rapid categorisation task, monkeys and humans had to detect a target (animal or food) in briefly flashed (32 ms) and previously unseen natural images. Removing colour cues had very little effect on average performance. Impairments were restricted to a mild accuracy drop (in some human subjects) and a small reacti...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(00)00083-3
更新日期：2000-01-01 00:00:00
abstract：:If a brief test pulse is presented on a prolonged background pedestal, it is strongly masked if presented at the start of the pedestal, and is only weakly masked if presented 200 ms after the start. This has been suggested to occur due to contrast gain mechanisms that reduce the representation of the pedestal and ther...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(01)00110-9
更新日期：2001-07-01 00:00:00
abstract：:This study compared frequency-of-seeing curves for a line displacement test in glaucoma patients and normals. Probit analysis of the frequency-of-seeing curves provided the motion thresholds and the slopes of the frequency-of-seeing curves, represented by the interquartile range. The thresholds and interquartile range...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(98)00187-4
更新日期：1999-02-01 00:00:00
abstract：:Three normal observers made visual matches from 0.03 to 100 td on a 10 degree central field at 445, 560 and 630 nm, using two different methods: heterochromatic flicker photometry and direct comparison brightness matching. In a relative sensitivity vs illuminance plot, the brightness matches underwent smooth changes, ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(92)90245-e
更新日期：1992-03-01 00:00:00
abstract：:We characterize the dark-adapted photoresponses from mouse cones intact in the isolated retina, their virtually natural environment, by isolating pharmacologically the photoreceptor light responses from the electroretinogram (ERG). Due to the different photoresponse kinetics and sensitivity of rods and cones, the cone...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2007.11.005
更新日期：2008-01-01 00:00:00
abstract：:Two eyes are better than one at detecting a pattern, an advantage termed binocular summation. It is widely believed that binocular summation is mediated by neurons that sum the two eyes' inputs. Here we suggest an alternative model based on a model of binocular interactions proposed by Cohn, Leong & Lasley (Vision Res...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2020.11.007
更新日期：2021-02-01 00:00:00
abstract：:Quite independently of what they represent, some images provoke discomfort, and even headaches and seizures in susceptible individuals. The visual system has adapted to efficiently process the images it typically experiences, and in nature these images are usually scale-invariant. In this work, we sought to characteri...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2014.12.013
更新日期：2015-03-01 00:00:00
abstract：:Motion coherence thresholds decline with an increase in the number of frames in a random dot kinematogram (RDK), indicating that motion information can be integrated across successive frames. We investigated whether such temporal integration would be disrupted by a brief interval (32-600 msec) inserted into a motion s...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(97)00178-8
更新日期：1998-02-01 00:00:00
abstract：:Spatial interactions among orientation-tuned gain control processes are presumed to mediate center-surround contrast-contrast phenomena. In this paper, we assess contributions of gain control processes that pool over orientation. We measured the apparent contrast of a luminance-modulated center disk embedded in variou...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(99)00131-5
更新日期：1999-12-01 00:00:00
abstract：:A Westheimer -like function has been obtained for simple reaction time (RT) to target luminance increments superimposed upon homogeneous background fields. RT to a constant-luminance target progressively increases as the outer diameter of a constant-luminance background is increased up to approximately 6'-8'. Further ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(84)90053-1
更新日期：1984-01-01 00:00:00
abstract：:The widespread nature of diabetes affects all organ systems of an individual including the bone marrow. Long-term damage to the cellular and extracellular components of the bone marrow leads to a rapid decline in the bone marrow-hematopoietic stem/progenitor cells (HS/PCs) compartment. This review will highlight the i...
journal_title：Vision research
pub_type： 杂志文章,评审
doi：10.1016/j.visres.2017.06.016
更新日期：2017-10-01 00:00:00
abstract：:Static visual stimulus presented behind a moving pattern inhibits vection. On the other hand, the same static stimulus facilitates vection if it is located in front of the moving pattern. In this study, the effects of depth, eccentricity and size of the additional static stimulus on inhibition and facilitation of hori...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2006.01.016
更新日期：2006-07-01 00:00:00
abstract：:Two protanopes, two deuteranopes, and two normal subjects named 424 OSA Uniform Color Scales samples using single-word color terms of their choice under three different experimental conditions. When viewing a stimulus field subtending about 4 deg, the performance of the dichromats revealed a substantial ability to dis...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(87)90129-5
更新日期：1987-01-01 00:00:00
abstract：:According to a top-down explanation of subliminal oculomotor capture, only subliminal distractors with a contrast polarity matching that of the searched-for targets should capture attention. For instance, when looking for white targets only subliminal white but not black distractors should capture attention. In contra...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2014.03.014
更新日期：2014-07-01 00:00:00
abstract：:Contrast sensitivity for both vertically and obliquely oriented gratings increased with increases in stimulus area to an asymptotic value. Sensitivity grew more slowly for oblique gratings and reached an asymptotic value at a larger area than for vertical gratings. For equal areas, oblique gratings always yielded poor...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(83)90060-3
更新日期：1983-01-01 00:00:00
abstract：:Microspectrophotometry (MSP) revealed that surprisingly for a "fully marine" species, in summer, photoreceptors of the nearshore scorpaeniform fish known as the masked greenling, Hexagrammos octogrammus, contained exclusively, or presumably, porphyropsin with a small admixture of rhodopsin. As a result of this, the la...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2008.07.004
更新日期：2008-09-01 00:00:00
abstract：:It is now clear, contrary to previous conclusions, that motion may be conveyed by purely chromatic stimuli. The question considered here is how the mechanisms for assessing motion of luminance and chromatic stimuli differ. The dependence on contrast of amplitude thresholds for the perception of oscillatory motion was ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(99)00044-9
更新日期：1999-10-01 00:00:00
abstract：:The role of the perceptual organization of the visual display on eye movement control was examined in two experiments using a task where a two-saccade sequence was directed toward either a single elongated object or three separate shorter objects. In the first experiment, we examined the consequences for the second sa...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2005.11.034
更新日期：2006-07-01 00:00:00
abstract：:The spatial extent of interference from nearby object or contours (the critical spacing of "crowding") has been thoroughly characterized across the visual field, typically using high contrast achromatic stimuli. However, attempts to link this measure with known properties of physiological pathways have been inconclusi...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2016.03.007
更新日期：2016-05-01 00:00:00
abstract：:The present study demonstrates that an object embedded in an array of identical objects can pop-out. Dependent on the stimuli preceding the search display, local (chromatic) adaptation causes an identical object to pop-out because it appears to have a colour (Expt 1) or brightness (Expt 2) that is slightly different f...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(93)90113-b
更新日期：1993-11-01 00:00:00
abstract：:Previous studies have indicated that peripheral resolution for achromatic gratings is sampling limited and directly related to the density of the underlying midget ganglion cell population. Previous studies by the authors have shown that peripheral resolution for blue-cone isolating gratings is also sampling limited, ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(02)00411-x
更新日期：2003-01-01 00:00:00
abstract：:Trout lens external shape and internal refractive index gradient structure were measured and used to construct an optical lens model that predicts by ray tracing the average longitudinal spherical and chromatic aberration, focal length and image quality. The nearly spherical shape of the lens was measured from photogr...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(95)00328-2
更新日期：1996-09-01 00:00:00
abstract：:The longitudinal chromatic aberration (LCA) of the human eye was determined between wavelengths 458 and 633 nm for ten observers by incorporating Argon and Helium-Neon Lasers into a Badal optometer system such that tonic (or "dark focus") resting positions of accommodation could be measured under darkroom conditions. ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(85)90148-8
更新日期：1985-01-01 00:00:00
abstract：:Characterization of the visual system as a linear system has many consequences. One property implied by such a characterization is that signal-to-noise ratio at threshold is constant, so that the contrast energy of a sinusoidal grating at threshold depends on the effective noise passed by the filter used to detect the...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(91)90209-n
更新日期：1991-01-01 00:00:00
