Search results for "Visual Perception"

Responses to eccentric rotation in two space-bound subjects

1993

Two subjects were rotated eccentrically in the manner described previously. In contrast to a normal control group, settings of a luminous line to the subjective vertical were almost unrelated to the gravitoinertial vector before, and totally so shortly after, space flight. Only 3 days postflight did a clear relation to the gravitoinertial vector re-establish itself in the one subject who actually flew. The correspondence became normal 5 days after the flight. Since there were no clinical abnormalities evident in the subjects, it is suggested that both subjects suppressed their vestibular information, presumably as an effect of vestibular deconditioning training before the flight. In additio…

<title>The perception of isoluminant coloured stimuli of amblyopic eye and defocused eye</title>

2008

In routine eye examination the visual acuity usually is determined using standard charts with black letters on a white background, however contrast and colour are important characteristics of visual perception. The purpose of research was to study the perception of isoluminant coloured stimuli in the cases of true and simulated amlyopia. We estimated difference in visual acuity with isoluminant coloured stimuli comparing to that for high contrast black-white stimuli for true amblyopia and simulated amblyopia. Tests were generated on computer screen. Visual acuity was detected using different charts in two ways: standard achromatic stimuli (black symbols on a white background) and isoluminan…

Processing of audiovisual associations in the human brain: dependency on expectations and rule complexity

2012

In order to respond to environmental changes appropriately, the human brain must not only be able to detect environmental changes but also to form expectations of forthcoming events. The events in the external environment often have a number of multisensory features such as pitch and form. For integrated percepts of objects and events, crossmodal processing, and crossmodally induced expectations of forthcoming events are needed. The aim of the present study was to determine whether the expectations created by visual stimuli can modulate the deviance detection in the auditory modality, as reflected by auditory event-related potentials (ERPs). Additionally, it was studied whether the complexi…

Evaluating the Effect of Stimuli Color and Frequency on SSVEP

2020

Brain&ndash

Chromostereopsis in "virtual reality" adapters with electrically tuneable liquid lens oculars

2016

Chromostereopsis can be sight and feel in “Virtual Reality” adapters, that induces the appearance of color dependant depth sense and, finally, combines this sense with the source conceived depth scenario. Present studies are devoted to investigation the induced chromastereopsis when using adapted “Virtual Reality” frame together with mobile devices as smartphones. We did observation of composite visual stimuli presented on the high spatial resolution screen of the mobile phone placed inside a portable “Virtual Reality” adapter. Separated for the left and right eyes stimuli consisted of two areas: a) identical for both eyes color chromostereopsis part, and b) additional conventional color ne…

Naming People Ignoring Semantics in a Patient with Left Frontal Damage

1999

Studies about proper name anomia generally assume that persons' names are harder to recall than other semantic information one knows about them and that name retrieval is not possible without biographical knowledge. We describe a patient, SB, who, after a left frontal haemorrhage, was unable to recall any biographical information about people she could name. Moreover, she had a normal score in an Object Picture Naming Test, but gave confabulatory answers in a Semantic Questionnaire involving the same items. The role of frontal function in producing this pattern of impairment is discussed, together with the possible existence of a direct route from visual perception to proper name retrieval.

Can Applications Designed to Evaluate Visual Function Be Used in Different iPads?

2018

SIGNIFICANCE: Apple devices could be suitable for vision tests, provided that the test has been correctly adapted to the device, after considering the spatial and colorimetric characterization of the screen. PURPOSE: The majority of vision applications has not been developed by vision or colorimetry experts and suffers from conceptual and design errors that may lead average users to an erroneous assessment of their visual capabilities. The reliability of vision tests depends on the accurate generation of the necessary visual stimuli in a particular device. Our aim was to ascertain whether a given color test, designed for a colorimetrically characterized device, might be used in another simi…

2016

Processing natural scenes requires the visual system to integrate local features into global object descriptions. To achieve coherent representations, the human brain uses statistical dependencies to guide weighting of local feature conjunctions. Pairwise interactions among feature detectors in early visual areas may form the early substrate of these local feature bindings. To investigate local interaction structures in visual cortex, we combined psychophysical experiments with computational modeling and natural scene analysis. We first measured contrast thresholds for 2x2 grating patch arrangements (plaids), which differed in spatial frequency composition (low, high or mixed), number of gr…

AcouMotion – An Interactive Sonification System for Acoustic Motion Control

2006

This paper introduces AcouMotion as a new hard-/software system for combining human body motion, tangible interfaces and sonification to a closed-loop human computer interface that allows non-visual motor control by using sonification (non-speech auditory displays) as major feedback channel. AcouMotion's main components are (i) a sensor device for measuring motion parameters (ii) a computer simulation to represent the dynamical evolution of a model world, and (iii) a sonification engine which generates an auditory representation of objects and any interactions in the model world. The intended applications of AcouMotion range from new kinds of sport games that can be played without visual di…

Perceptual Processing and the Comprehension of Relational Information in Dynamic Diagrams

2018

International audience; To date, research on the processing involved in comprehending and learning from animated diagrams has accorded a minor role only to perceptual operations in general and peripheral processing in particular. For those aspects where the role of perception is acknowledged, it is foveal rather than peripheral processing that is regarded as the main player. In this paper, we use the results from additional finer grained analysis of data collected in a recent empirical study to suggest that information from a viewer’s peripheral field can play a much more central role in animation processing than has previously been recognized. It appears that if the dynamic information com…