Showing papers in "Vision Research in 1988"

TL;DR: It was found that the posterior nodal distance was increased in eyes which were treated with negative lenses compared to those treated with positive lenses, and this effect occurs independently in both eyes and it is not due to changes in corneal curvature.

TL;DR: In this article, eye movement data were analyzed to identify factors that influence the location of a reader's initial eye fixation on a word, and the locations of initial fixations on words can be accounted for on the basis of five principles of perceptuo-oculomotor control.

TL;DR: In the present experiments three different motion discrimination tasks were studied using a random dot pattern as stimulus: velocity discrimination, direction discrimination and discrimination of opposite directions, indicating that the pooling requirements are task dependent.

TL;DR: Analysis of how aging affects spatial contrast sensitivity at low light levels and whether senile miosis underlies any observed sensitivity loss indicated that older adults' loss in contrast sensitivity not only increased with increasing spatial frequency, but also became more pronounced with decreases in luminance level.

TL;DR: A model of foveal cone sampling that shows how these moiré patterns depend on the spatial frequency and orientation of an interference fringe imaged on a triangular lattice of cones is described.

TL;DR: A simple model for adaptation is proposed to account for the findings which is based on a shift in the semi-saturation constant of the detector's contrast-response function and acts to linearize the underlying mechanism's response in the region near the prevailing contrast level.

TL;DR: Although the color adaptation effects appear slightly less selective than those for luminance, the results suggest similar spatial processing of color and luminance contrast patterns by early stages of the human visual system.

TL;DR: An examination of infant neuroanatomical data suggests that three major factors are involved in the development of these mechanisms, which are developed into a quantitative model which is shown to provide a coherent interpretation of many of the psychophysical data on infant vision.

TL;DR: A mathematical model was developed to predict an observer's sensitivity to small changes in motion direction based on two assumptions: (1) the computed velocity signal is obtained from the intersection of constraint lines defined by local velocity components, and (2) local Velocity components are contaminated by noise.

TL;DR: There exists a class of two-dimensional figures (including cumulative gaussian waveforms) whose contours have a limited range of orientations and these figures can appear as highly nonrigid if they undergo pure translation in the image plane.

TL;DR: Evidence from six experiments shows that stimulus manipulations which reduce direct effects have little or no effect on indirect effects and vice versa, suggesting that the two effects have different determinants.

TL;DR: It is proposed that stereo information is effectively integrated only where the surface exhibits curvature features or edge discontinuities, i.e. where the second spatial derivatives of disparity are nonzero.

TL;DR: Two mechanisms of brightness perception, brightness induction by local contrast and assimilation, were examined for a variety of visual stimuli to compare the relative strength of the two effects using stimuli which permit them to be studied separately.

TL;DR: Comparison threshold measurements with the same set of stimuli confirmed earlier reports that the meridional anisotropy for contrast detection increases with test spatial frequency.

TL;DR: A chicken genomic library was screened with a bovine opsin cDNA probe as discussed by the authors, which revealed that this DNA fragment contains the complete chicken opsin gene and the position of four introns and amino acid sequences at all putative cytoplasmic loops in chicken and mammals.

TL;DR: Microspectrophotometric measurements of visual pigments have been obtained for a large sample of New World monkeys of the species Callithrix and it appears that polymorphisms of cone pigments may be widespread among neotropical primates.

TL;DR: No difference was found between acceleration and deceleration ringing dynamics, except for decelerations to 0 +/- 2 deg/sec, suggesting that around zero velocity, the central nervous system switches off pursuit and adopts fixation, which supports the idea that fixation and pursuit represent different neurological systems.

TL;DR: Results indicate that changing size is stimulating accommodation directly and vergence secondarily through an AC/A crosslink.

TL;DR: The data are explained by the hypothesis that the passage of a retinal locus by a moving target image is experienced faster when the image moves foveopetally, regardless of whether the passage is caused by real target movement or by ocular pursuit.

TL;DR: The data are consistent with the view that refractive properties of the chick eye are dependent upon the clarity of the visual image and modulation of these features occurs after hatching.

TL;DR: The term sensation luminance is proposed when light measures are made which depend on individual observer's spectral sensitivity, and when sensation Luminance is used to calculate retinal illuminance the term sensation trolands is proposed.

TL;DR: The psychophysical results show a close correlation to the cortical organization as revealed by autoradiography, and the naso-temporal asymmetry in the periphery of the visual field is much more pronounced for hyperacuity than for spatial resolution.

TL;DR: This result provides the first direct evidence that a nonhuman perceives subjective contours, and is likely to be the most important in the history of research on this topic.

TL;DR: The variation in sphero-cylindrical refractive error with position in the human eye pupil is derived from the wavefront error of two subjects and the modulation transfer function is calculated for 1, 2 and 3 mm pupils decentred 1 and 2 mm nasally and temporally.

TL;DR: The distributions of durations of fixations from infants and free-viewing adults are shown to be basically exponential for different stimulus conditions and it is shown that mean duration decreases when stimulus size increases.

TL;DR: The kinematics of centrifugal and centripetal saccadic eye movements were quantified in human subjects and indicate that initial eye position must be considered before comparing saccades based on their kinematic properties.

TL;DR: The human visual system is capable of assigning a single location tag to an entire Gaussian modulated patch of sinusoidal grating and the accuracy with which the relative position of such a Gabor patch can be determined in a constant fraction of its spatial extent.

TL;DR: In experiments using a bistable apparent motion stimulus, it was found that perceived motion is a stimulus for anticipatory slow eye movements, which can explain previously noted differences between these predictive movements and the predictive component of smooth pursuit.

TL;DR: In this paper, the authors investigated the interaction between size and orientation-specific mechanisms in the human visual system using a sequential adaptation technique and found the existence of inhibitory interactions between neural mechanisms tuned to the size and orientations of retinal images.

TL;DR: The separate functions for the conditions of inducing letters of high and low figural similarity with TS were coinciding, thus pointing to the nonspecific nature of the obtained effect within the given spatial constraints.