A computational model of selective deficits in first and second-order motion processing.

abstract：:Sensory, cognitive and motor processing can result in changes of the ongoing EEG in form of an event-related desynchronization (ERD) or event-related synchronization (ERS). Both phenomena are time-locked but not phase-locked to the event and they are highly frequency-band specific. The ERD is interpreted as a correlat...

journal_title：Vision research

authors： Pfurtscheller G

更新日期：2001-01-01 00:00:00

abstract：:Perception of short-range motion was studied as a function of adapting luminance and of stimulus contrast in computer simulations and in psychophysical experiments. The stimuli were random dots plotted on an oscilloscope in two sequential frames, separated by an inter-stimulus interval (ISI). Both in the simulations a...

journal_title：Vision research

authors： Dawson M,Di Lollo V

更新日期：1990-01-01 00:00:00

abstract：:We compared a human observer's ability to locate the focus of expansion (FOE) of a radial optic flow field when this flow field was either combined with, or overlapped by, planar motion. With combined stimuli, in which the FOE was displaced in the direction opposite to the planar motion, subjects accurately located th...

journal_title：Vision research

authors： Duffy CJ,Wurtz RH

更新日期：1993-07-01 00:00:00

abstract：:Objects are usually segregated from ground by several visual dimensions. We studied texture segregation in checkerboards defined by gradients in spatial frequency, orientation or both frequency and orientation, using Gabor-filtered noise patterns. Saliency was measured electrophysiologically using the visual evoked po...

journal_title：Vision research

authors： Bach M,Schmitt C,Quenzer T,Meigen T,Fahle M

更新日期：2000-01-01 00:00:00

abstract：:The grasshopper Phlaeoba sp. has ocular filters that are arranged in discrete retinal bands. These filters modify the spectra of some of its photoreceptors, all of which are apparently filled with the same resident photopigment. The receptor response differences produced by the ocular filters provide a potential basis...

journal_title：Vision research

authors： Wasserman GS,Kong KL

更新日期：1982-01-01 00:00:00

abstract：:Vernier thresholds were measured behaviourally in five cats using offsets in gratings of two spatial frequencies and in single lines. Thresholds ranged from 2.2 to 6.7', and no threshold differences were found across stimuli. These results are discussed in relationships with published spatial resolution data and are r...

journal_title：Vision research

authors： Belleville S,Wilkinson F

更新日期：1986-01-01 00:00:00

abstract：:We investigated the interactions between flicker thresholds and luminance pedestals using threshold versus contrast (TvC) and method of constant stimuli paradigms. High amplitude luminance pedestals were found to elevate flicker thresholds, but low amplitude luminance pedestals were unable to reduce flicker thresholds...

journal_title：Vision research

authors： Anderson AJ,Vingrys AJ

更新日期：2000-01-01 00:00:00

abstract：:Flanking lateral masks enhance or weaken the detection of a low-contrast visual target. This effect depends on the target-to-mask distance. An improvement of stimulus detection can also be observed when participants imagine (i.e., retrieve from memory) the previously presented masks. In this double-blind, placebo-cont...

journal_title：Vision research

authors： Kéri S

更新日期：2015-01-01 00:00:00

abstract：:Glass patterns are randomized dot arrays that generate the perception of a global structure. They consist of correlated dot pairs which are generated by geometric transformations. The present study employed behavioral and event-related brain potential (ERP) measures to characterize the underlying neuronal processing w...

journal_title：Vision research

authors： Ohla K,Busch NA,Dahlem MA,Herrmann CS

更新日期：2005-09-01 00:00:00

abstract：:Varying short-range apparent motion (AM) stimulus displacements from 2.7 to 21.6 min it was found that VEP amplitudes varied as a function of the limits for short-range AM described using time-till-breakdown as a behavioural measure of AM strength. This VEP amplitude difference was, however, in the reverse direction t...

journal_title：Vision research

authors： Manning ML,Finlay DC,Fulham WR

更新日期：1991-01-01 00:00:00

abstract：:Two alternative schemes have been proposed for coding the local direction of stimulus motion in the visual image. The "sequence discrimination" scheme (e.g. Barlow H.B. and Levick W. R., J. Physiol., Lond. 178, 477-504, 1965) uses sequential change in stimulus position over time to infer movement direction; the "spati...

journal_title：Vision research

authors： Mather G

更新日期：1984-01-01 00:00:00

abstract：:The topography of visual evoked potentials (VEP) is dependent on occipital lobe morphology. Using magnetic resonance imaging we examine the sulcal pattern (the calcarine and parieto-occipital sulci), and assess the size of the cuneus and the asymmetry of the occipital lobes, computed separately for its ventral and dor...

journal_title：Vision research

authors： Myslobodsky MS,Glicksohn J,Coppola R,Weinberger DR

更新日期：1991-01-01 00:00:00

abstract：:The precision to locate individual features in depth can often be improved by integrating information over space. However, this integration can sometimes be extremely detrimental, as for example in the case of the Westheimer-McKee phenomenon where features are grouped to form an object. We replicate here the known los...

journal_title：Vision research

authors： Mamassian P,Zannoli M

更新日期：2020-09-01 00:00:00

abstract：:We describe and analyze an appearance-based 3-D object recognition system that avoids some of the problems of previous appearance-based schemes. We describe various large-scale performance tests and report good performance for full-sphere/hemisphere recognition of up to 24 complex, curved objects, robustness against c...

journal_title：Vision research

authors： Nelson RC,Selinger A

更新日期：1998-08-01 00:00:00

abstract：:After viewing directional motion, one is likely to perceive a subsequently presented directionally ambiguous motion as being in the same direction as the prior motion. The perceptual bias towards the most recent percept gradually develops as the interval between the prior stimulus and a subsequent test becomes longer....

journal_title：Vision research

authors： Kanai R,Knapen TH,van Ee R,Verstraten FA

更新日期：2007-09-01 00:00:00

abstract：:This paper reports an improved paradigm to measure visible persistence. The stimulus is a pair of lines stroboscopically displayed in successive positions moving in opposite directions. The subjects' judgement of simultaneous appearance of all the presented lines is used to estimate visible persistence. This paradigm ...

journal_title：Vision research

authors： Farrell JE,Pavel M,Sperling G

更新日期：1990-01-01 00:00:00

abstract：:The response latency of horizontal cells in the carp retina was investigated by means of the stimulus-response crosscorrelation using a randomly modulated light of various wavelengths. R/G type cells produced two response components with some difference in latency; short-latency hyperpolarising response to green light...

journal_title：Vision research

authors： Yamada M,Shigematsu Y,Fuwa M

更新日期：1985-01-01 00:00:00

abstract：:In hyperacuity, as in many other tasks, performance improves with practice. To better understand the underlying mechanisms, we measured thresholds of 41 inexperienced observers for the discrimination of vernier displacements. In spite of considerable inter-individual differences, mean thresholds decreased monotonicall...

journal_title：Vision research

authors： Fahle M,Edelman S

更新日期：1993-02-01 00:00:00

abstract：:Random-dot cinematograms comprising many different, spatially intermingled local motion vectors can produce a percept of global coherent motion in a single direction. Thresholds for discriminating the direction of global motion were measured under various conditions. Discrimination thresholds increased with the width ...

journal_title：Vision research

authors： Watamaniuk SN,Sekuler R

更新日期：1992-12-01 00:00:00

abstract：:When each eye is confronted with a dissimilar stimulus, the percept will generally alternate between the two. This phenomenon is known as binocular rivalry. Although binocular rivalry occurs at locations where targets overlap spatially, the area surrounding rivalrous targets can modulate their dominance. Here we show ...

journal_title：Vision research

authors： Paffen CL,te Pas SF,Kanai R,van der Smagt MJ,Verstraten FA

更新日期：2004-01-01 00:00:00

abstract：:The effects of abrupt increases and decreases of light in one part of the retina on sensitivity in an adjacent part of the retina were studied under low scotopic conditions near absolute threshold. The basic finding is that a brief annular surround decreases sensitivity to test spots occurring near the time of its ons...

journal_title：Vision research

authors： Pulos E,Makous W

更新日期：1982-01-01 00:00:00

abstract：:Monocular acuity, binocular acuity, and stereopsis were assessed with preferential-looking techniques in a sample of 114 normal infants aged 0-11 months in order to examine developmental trends in: (1) interocular differences in acuity, (2) test-retest reliability, (3) the relationship between monocular and binocular ...

journal_title：Vision research

authors： Birch EE

更新日期：1985-01-01 00:00:00

abstract：:Spatial cueing of transient attention has recently been shown to reduce temporal sensitivity. We investigated how the size of the sustained attentional focus influences double-pulse resolution (DPR) thresholds mapped across the visual field in a sample of 95 healthy subjects using a 9-fold interleaved adaptive algorit...

journal_title：Vision research

authors： Poggel DA,Treutwein B,Calmanti C,Strasburger H

更新日期：2006-09-01 00:00:00

abstract：:Minimum displacement thresholds were measured using a compound motion stimulus, in which a single bar split into oppositely moving components, having different luminances and absolute displacements. The results fit a simple model in which observers detect the movement of the centroid of the combined luminance pattern ...

journal_title：Vision research

authors： Morgan MJ,Ward RM,Cleary RF

更新日期：1994-03-01 00:00:00

abstract：:Saleh and Bonnet [Fechner Day 98, p. 344] have shown that, upon parafoveal stimulation and up to 6.5 c/deg, reaction time (RT) is a function of grating contrast multiplied by grating period. The present experiments extend these findings to foveal stimulation within a wider spatial-frequency (SF) range and to stimuli o...

journal_title：Vision research

authors： Vassilev A,Mihaylova M,Bonnet C

更新日期：2002-03-01 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

authors： Bex PJ,Simmers AJ,Dakin SC

更新日期：2003-09-01 00:00:00

abstract：:We investigated the effect of adaptation on orientation discrimination using two experienced observers, then replicated the main effects using a total of 50 naïve subjects. Orientation discrimination around vertical improved after adaptation to either horizontal or vertical gratings, but was impaired by adaptation at ...

journal_title：Vision research

authors： Clifford CW,Wyatt AM,Arnold DH,Smith ST,Wenderoth P

更新日期：2001-01-15 00:00:00

abstract：:We designed two extensions of Saslow's well-known gap and overlap conditions that require increased voluntary effort because of the progressive elimination of target onsets and fixation point offsets, and obtained repeatable data obeying simple numerical relations. For each of the five stimulus lighting conditions, sa...

journal_title：Vision research

authors： Kalesnykas RP,Hallett PE

更新日期：2002-03-01 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

authors： Vienot F,Chiron A

更新日期：1992-03-01 00:00:00

abstract：:Behavioral measures of spatial summation in 4- and 11-week old human infants were obtained using the forced-choice preferential looking technique. Infants exhibit complete spatial summation over large areas (4 weeks: 8.9 degrees; 11 weeks: 5.5 degrees), much larger than those of adults tested in the same apparatus (2....

journal_title：Vision research

authors： Hamer RD,Schneck ME

更新日期：1984-01-01 00:00:00