scholarly journals Scintillating Grid Illusion Without the Grid

i-Perception ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 204166952094441
Author(s):  
Toyomi Matsuno
Keyword(s):  
Stimulus Pattern ◽  
Peripheral Vision ◽  
Grid Pattern ◽  
Essential Component ◽  
Contour Shape ◽  
Spatial Alignment ◽  
Black Spots

The scintillating grid illusion is a phenomenon where illusory black spots are perceived on white patches located at the intersections of a grid pattern. In this study, I report that the illusory spots as observed in the illusion are perceived with a stimulus pattern without grid bars. In two experiments, I investigated the perceptual properties of the scintillating illusion without grid bars. I found that the strength of the illusion depends on the contour shape of the patch components as in the scintillating grid illusion, while neither the density nor spatial alignment largely affect the illusory percepts. These findings undermine the previous theories on the mechanism of the scintillating grid illusion, as it was assumed that the grid bars are the essential component to induce the illusion. The results suggest that the illusory spots of the scintillating grid illusion could be induced by the limited processing of the patch stimuli in the peripheral vision and that the grid could play a supplementary role by enhancing the effect by further interfering with the processing.

The Graph-Paper Effect: Subjective Stereoscopic Patterns Induced by Moving Gratings

Perception ◽  
1980 ◽  
Vol 9 (5) ◽  
pp. 503-522 ◽  
Author(s):  
Mark A Georgeson
Keyword(s):  
Stimulus Pattern ◽  
Second Harmonic ◽  
Previous Model ◽  
Movement Direction ◽  
Phase Lag ◽  
Grid Pattern ◽  
Graph Paper ◽  
Smooth Tracking ◽  
Phase Preference

Smooth tracking across an oblique grid pattern produced hallucinations of vertical and/or horizontal striations which moved with the eyes. The effect was produced by single or multiple gratings, monocularly or binocularly, but in the latter case it appeared to lie stereoscopically in the plane of fixation. Gratings containing thin lines or sawtooth edges of moderate contrast were particularly effective stimuli but sine or square waves were not. The subjective stripes had an apparent edge polarity which was opposite to that of the inducing edges or, with thin inducing lines, was determined by the lines' polarity and movement direction. Conventional explanations (eg strobe, afterimage, or moiré effects) can be ruled out. Neither the present effect nor the ‘pincushion-grid illusion’ are due to the presence of spurious Fourier components in the stimulus pattern. An extension of a previous model, involving disinhibitory interaction between movement and pattern channels, accounts for many aspects of this elaborate phenomenon. The detailed dependence of polarity on spatial waveform and movement direction implies: (i) the spatial second harmonic is a necessary component, (ii) the generating mechanism is approximately linear and has 90° phase preference, and (iii) there is a movement-induced phase lag of about 45° in the response to the second harmonic.

Redundancy Gain in Discrimination of Colored Lights: Effects of Complexity and Eccentricity

1998 ◽  
Vol 86 (2) ◽  
pp. 691-697
Author(s):  
Yoshiaki Nakajima ◽  
Satoru Kawamura
Keyword(s):  
Visual Angle ◽  
Stimulus Pattern ◽  
Peripheral Vision ◽  
Redundancy Gain ◽  
Low Complexity ◽  
Complex Stimulus ◽  
High Complexity ◽  
Redundant Target Effect ◽  
Target Effect ◽  
Colored Lights

The present study investigated the redundancy gain in discrimination of colored lights. Subjects were requested to discriminate a target from 34 nontarget lights differing from the target in luminance, hue, or both, and RTs were recorded. Experimental variables were the complexity of stimulus pattern and the eccentricity of the target in visual angle. The 35 lights were arranged regularly on an imaginary grid in the low-complexity condition and were arranged randomly in the high-complexity condition. The eccentricity of target was varied from 0° to 16°. Only when the stimulus pattern was highly complex and eccentricity was large, the combination of luminance and hue made the subject's discrimination faster than when luminance or hue individually operated as a cue for discrimination. That is, a redundant target effect was found only for a highly complex stimulus pattern and in peripheral vision.

Domain Formation in Synthetic Quartz

1971 ◽  
Vol 29 ◽  
pp. 156-157
Author(s):  
Joseph J. Comer
Keyword(s):  
Electron Beam ◽  
Room Temperature ◽  
Domain Formation ◽  
Synthetic Quartz ◽  
Transmission Electron ◽  
Black Spots ◽  
Diffraction Mode ◽  
Domain Boundaries ◽  
Kikuchi Lines ◽  
Straight Lines

Domains visible by transmission electron microscopy, believed to be Dauphiné inversion twins, were found in some specimens of synthetic quartz heated to 680°C and cooled to room temperature. With the electron beam close to parallel to the [0001] direction the domain boundaries appeared as straight lines normal to <100> and <410> or <510> directions. In the selected area diffraction mode, a shift of the Kikuchi lines was observed when the electron beam was made to traverse the specimen across a boundary. This shift indicates a change in orientation which accounts for the visibility of the domain by diffraction contrast when the specimen is tilted. Upon exposure to a 100 KV electron beam with a flux of 5x 1018 electrons/cm2sec the boundaries are rapidly decorated by radiation damage centers appearing as black spots. Similar crystallographio boundaries were sometimes found in unannealed (0001) quartz damaged by electrons.

FT-IR microspectroscopic analysis of diseased white matter brain tissues

1995 ◽  
Vol 53 ◽  
pp. 968-969
Author(s):  
Steven M. Le Vine ◽  
David L. Wetzel
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Twitcher Mouse ◽  
Grid Pattern ◽  
Marked Contrast ◽  
Spatially Resolved ◽  
Ft Ir ◽  
Ir Microspectroscopy ◽  
Chemical Evidence

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.

Roll axis tracking improvement resulting from peripheral vision motion cues

1976 ◽  
Author(s):  
Thomas E. Moriarty ◽  
Andrew M. Junker ◽  
Don R. Price
Keyword(s):  
Peripheral Vision ◽  
Motion Cues ◽  
Roll Axis

Research of Information Presenting Method Based on Characteristics of Peripheral Vision

2013 ◽  
Vol 133 (1) ◽  
pp. 2-7 ◽  
Author(s):  
Kensuke Tobitani ◽  
Kunihito Kato ◽  
Kazuhiko Yamamoto
Keyword(s):  
Peripheral Vision

CRITICAL STUDY ON DATABASE AND PROMINENT PROGRAMMES

2013 ◽  
Vol 4 (1) ◽  
pp. 44-47
Author(s):  
Dr. Vinod Kumar ◽  
Gagandeep Raheja ◽  
Sukhpreet Singh
Keyword(s):  
Human Brain ◽  
Everyday Life ◽  
Modern Society ◽  
Database Systems ◽  
Simple Device ◽  
Critical Study ◽  
Essential Component ◽  
The People

The people who work with computers, the programmers, analysts, and operators who seem to live by rules of their own and seldom leave their own environment, tend to be very cynical towards the stories of electronic brains. This attitude will appear hardly surprising when one eventually learns that the computer is a very simple device and is as far removed from an electronic brain as a bicycle from a spaceship. Programmers in particular are the people most aware that computers are no substitute for the human brain; in fact, the preparation of work to be run on a computer can be one of the most mind-bending exercises encountered in everyday life. Databases and database systems have become an essential component of everyday life in modern society. In the course of a day, most of us encounter several activities that involve some interaction with a database. So in this paper we will talk about how to manage the different type of data involved in any form in the database.

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