Active confocal imaging for visual prostheses.

abstract：:This study investigated the ability of human observers to discriminate the direction of laterally-moving cyclopean stimuli, in order to assess some of the properties of stereoscopic mechanisms that mediate the perception of cyclopean motion (motion existing at levels of binocular integration). The stimuli were moving ...

journal_title：Vision research

authors： Patterson R,Ricker C,McGary J,Rose D

更新日期：1992-01-01 00:00:00

abstract：:Dynamic random-dot stereograms (RDS) were used to study cortical neuronal mechanisms related to visual persistence in nine subjects. Electric brain potential components evoked by stereoscopic stimuli were compared to those evoked by conventional checkerboard stimuli with contrast borders. In a pattern-onset/offset pre...

journal_title：Vision research

authors： Skrandies W

更新日期：1987-01-01 00:00:00

abstract：:A number of experiments were conducted to investigate the interaction of the ON and OFF pathways in the processing of global-motion signals. The stimulus employed was a variant of that used by Newsome and Pare [(1988) Journal of Neuroscience, 8, 2201-2211] in which a small subset of dots move in a common (global-motio...

journal_title：Vision research

authors： Edwards M,Badcock DR

更新日期：1994-11-01 00:00:00

abstract：:In the classic double-step paradigm, subjects are required to make a saccade to a visual target that is briefly presented at one location and then shifted to a new location before the subject has responded. The saccades in this situation are "reflexive" in that they are made in response to the appearance of the target...

journal_title：Vision research

authors： Sheliga BM,Brown VJ,Miles FA

更新日期：2002-07-01 00:00:00

abstract：:We examined the ability of observers to determine the vertical alignment of three Gabor patches (cosine gratings tapered in X and Y by Gaussians) when the grating within the middle patch was moving right or left. The comparison patches were flickered in counterphase, as was the test patch in a control condition. In al...

journal_title：Vision research

authors： De Valois RL,De Valois KK

更新日期：1991-01-01 00:00:00

abstract：:This paper describes evidence for spatial aliasing in human motion perception. For a certain range of spatial frequencies, interference fringes drifting across the extrafoveal retina resemble two-dimensional spatial noise drifting in the opposite direction. For retinal locations within 10 deg of the fovea, the perceiv...

journal_title：Vision research

authors： Coletta NJ,Williams DR,Tiana CL

更新日期：1990-01-01 00:00:00

abstract：:We have measured corneal and total astigmatism on 161 eyes of 90 normal infants and young children aged 2 months to 5 years using the techniques of photorefraction and photokeratometry. Both the mean corneal and mean total astigmatism were found to decrease with increasing age. We found large and significant correlati...

journal_title：Vision research

authors： Howland HC,Sayles N

更新日期：1985-01-01 00:00:00

abstract：:Human subjects perceive two crossing bars, one in front of the other, when shown a cross with disparity added to its horizontal limbs, and they also perceive neon-color spreading when shown a stereoscopic Redies-Spillmann figure. It has thus been hypothesized that the human visual system follows the principle of gener...

journal_title：Vision research

authors： Uka T,Tanaka H,Kato M,Fujita I

更新日期：1999-07-01 00:00:00

abstract：:Age-related macular degeneration (AMD) is characterized by a central vision loss. Here, we investigated the ability of AMD patients to process the spatial frequency content of scenes in their residual vision, depending of the luminance contrast level. AMD patients and normally-sighted elderly participants (controls) p...

journal_title：Vision research

authors： Peyrin C,Ramanoël S,Roux-Sibilon A,Chokron S,Hera R

更新日期：2017-01-01 00:00:00

abstract：:Although the blind spot encodes no visual information, one never perceives an odd blob or blank there, but sees a complete scene of the world even when viewing monocularly. This phenomenon called "filling-in" might be related to mechanisms essential to surface perception, but the neural representation has still been u...

journal_title：Vision research

authors： Murakami I

更新日期：1995-04-01 00:00:00

abstract：:In Experiment 1 we investigated the independent and combined effects of horizontal OKN of stationary edges and occlusion of the central retina. For a display 60 degrees wide moving at 30 degrees/sec a symmetrically placed pair of vertical nonoccluding bars suppressed OKN when near the center of the display but had no ...

journal_title：Vision research

authors： Murasugi CM,Howard IP,Ohmi M

更新日期：1986-01-01 00:00:00

abstract：:The change in sensitivity across some stimulus dimension which follows adaptation to a particular stimulus can reveal a great deal about the tuning characteristics of underlying sensory/perceptual mechanisms. In this study, a psychophysical adaptation paradigm was employed to characterize the disparity tuning of perce...

journal_title：Vision research

authors： Stevenson SB,Cormack LK,Schor CM,Tyler CW

更新日期：1992-09-01 00:00:00

abstract：:Which visual channel detects high spatial frequencies during careful fixation? Color vision models based on psychophysical data contradict electrophysiological results. According to electrophysiology, the channel which mediates foveal acuity originates in the small, tonic color-opponent r-g units of the X-cell pathway...

journal_title：Vision research

authors： Ingling CR Jr,Martinez-Uriegas E

更新日期：1983-01-01 00:00:00

abstract：:The activity of neurones in cat striate cortex in response to laterally moving sinusoidal gratings has been examined. The effect of prolonged visual stimulation with a high contrast moving grating stimulus of optimal orientation and spatial frequency was investigated in terms of the changes wrought in the relationship...

journal_title：Vision research

authors： Dean AF

更新日期：1983-01-01 00:00:00

abstract：:To study the L- and M-cone pathways and their interactions in patients with cone and cone-rod dystrophies, ERG responses were measured to stimuli which modulated exclusively the L- or the M-cones, or the two simultaneously. The L- and M-cone driven ERG amplitudes were considerably reduced in the patients. The mean pha...

journal_title：Vision research

authors： Scholl HP,Kremers J

更新日期：2003-10-01 00:00:00

abstract：UNLABELLED:Taurine transporter knockout mice show severe retinal degeneration at an early age. The study was designed to determine whether degeneration also takes place in the absence of light. Mice were maintained up to 6 weeks of age in cyclic lighting or in total darkness. Degeneration took place in both groups, but...

journal_title：Vision research

authors： Rascher K,Servos G,Berthold G,Hartwig HG,Warskulat U,Heller-Stilb B,Häussinger D

更新日期：2004-01-01 00:00:00

abstract：:The contrast of a two-dimensional compound grating consisting of 2, 3 or 4 components with the same spatial frequency but different orientations was matched to the contrast of a simple cosine grating. At all spatial frequencies and contrast levels studied the stimuli which matched in apparent contrast had nearly equal...

journal_title：Vision research

authors： Tiippana K,Näsänen R,Rovamo J

更新日期：1994-05-01 00:00:00

abstract：:Observers viewed 200 msec presentations of gratings containing first (0.5 c/deg) and third (1.5 c/deg) harmonic components. The phase of the third harmonic and the absolute position of the grating on the screen varied randomly from trial to trial. Classification of the phase relation (0, 90, 180 or 270 deg was 99% per...

journal_title：Vision research

authors： Georgeson MA,Turner RS

更新日期：1984-01-01 00:00:00

abstract：:We measured increment thresholds up to 5 degrees eccentricity using a 10' dia flash viewed against 10(4) td of 572-nm background. We found two distinct sensitivity profiles, one with flash wavelengths 410-470 nm and another with 520-580 nm. Spectral sensitivity plots indicate blue-sensitive cones and green-sensitive c...

journal_title：Vision research

authors： Castańo JA,Sperling HG

更新日期：1982-01-01 00:00:00

abstract：:When two sinusoidal gratings of the same orientation and similar spatial frequency are summed, the resulting pattern has a periodic spatial variation or beat in contrast. Although the pattern contains no luminance modulation component at the beat frequency, it behaves in some respects as if it did: human observers for...

journal_title：Vision research

authors： Badcock DR,Derrington AM

更新日期：1989-01-01 00:00:00

abstract：:It has been known for some time that visual acuity in amblyopia is higher for single letters than for letters in a row (termed crowding). Early work showed that this could not be accounted for on the basis of the destructive interaction of adjacent contours (termed contour interaction), which was shown to be, in resol...

journal_title：Vision research

authors： Hess RF,Dakin SC,Tewfik M,Brown B

更新日期：2001-08-01 00:00:00

abstract：:Using a variety of measures it has been shown that processing time increases with increasing spatial frequency. Long and Sakitt (1981) [Vision Res. 21, 1387-1393] investigated duration of visible persistence as a function of both spatial frequency and number of cycles present. They concluded that number of cycles and ...

journal_title：Vision research

authors： Lovegrove WJ,Meyer GE

更新日期：1984-01-01 00:00:00

abstract：:This paper discusses a number of points that arise in the visual interpretation of optic flow fields. Particular attention is given to the case in which a flow field is visually ambiguous, and the paper concludes with a detailed description of the case of the moving plane. ...

journal_title：Vision research

authors： Longuet-Higgins HC

更新日期：1986-01-01 00:00:00

abstract：:We investigated the manner in which the outputs of the three postreceptoral mechanisms (red-green, blue-yellow and luminance) combine to determine contrast threshold. We used a subthreshold summation paradigm to test whether the combination of the postreceptoral mechanism outputs could be described by a probability su...

journal_title：Vision research

authors： Mullen KT,Sankeralli MJ

更新日期：1999-02-01 00:00:00

abstract：:During free viewing visual search, observers often refixate the same locations several times before and after target detection is reported with a button press. We analyzed the rate of microsaccades in the sequence of refixations made during visual search and found two important components. One related to the visual co...

journal_title：Vision research

authors： Privitera CM,Carney T,Klein S,Aguilar M

更新日期：2014-02-01 00:00:00

abstract：:Mach bands are illusory bright and dark bands seen where a luminance plateau meets a ramp, as in half-shadows or penumbras. A tremendous amount of work has been devoted to studying the psychophysics and the potential underlying neural circuitry concerning this phenomenon. A number of theoretical models also have been ...

journal_title：Vision research

authors： Pessoa L

更新日期：1996-10-01 00:00:00

abstract：:Electrophysiological studies have established that lead exposure produces selective rod deficits. The present electroretinographic (ERG) and correlated calcium experiments examined whether low-level or moderate-level developmental lead exposure (peak blood lead of 19 and 59 micrograms/dl, respectively) altered dark ad...

journal_title：Vision research

authors： Fox DA,Katz LM

更新日期：1992-02-01 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

authors： Vergilino-Perez D,Findlay JM

更新日期：2006-07-01 00:00:00

abstract：:A long-wavelength background can affect the appearance of an increment of light superimposed upon it in two ways. It can change the visual system's sensitivity to the increment, and it can change the appearance of the increment by directly adding redness to it. Through selective retinal-image stabilization, we evoked ...

journal_title：Vision research

authors： Nerger JL,Piantanida TP,Larimer J

更新日期：1993-01-01 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

authors： Theeuwes J,Lucassen MP

更新日期：1993-11-01 00:00:00