Duration of Stimulus Presentation and Screening for Perceptual Disabilities

1975 ◽  
Vol 40 (1) ◽  
pp. 49-50 ◽  
Author(s):  
Michael E. Rohr ◽  
Jerry B. Ayers
Keyword(s):  
Special Education ◽  
Motion Picture ◽  
Stimulus Presentation ◽  
Fourth Grade ◽  
Presentation Time ◽  
Total Performance ◽  
Screening Device

This study examined the effects of increasing the stimulus-presentation time of a motion picture test for identifying perceptual disabilities in the performance of Ss in regular first and fourth grade classrooms and on a sample of Ss in special education classes who had been identified as having varying degrees of perceptual deficiencies. The length of stimulus presentation increased the total performance of Ss on the motion picture test but did not add to the value of the instrument as a screening device.

Motion-Picture Screening Device for the Identification of Perceptual Disabilities

1974 ◽  
Vol 39 (1) ◽  
pp. 347-352 ◽  
Author(s):  
Michael E. Rohr ◽  
Jerry B. Ayers
Keyword(s):  
Motion Picture ◽  
Test Scores ◽  
Screening Test ◽  
Fourth Grade ◽  
Minimal Cost ◽  
Perceptual Development ◽  
Group Situation ◽  
Screening Device

The purpose of this study was to determine the validity of the Purdue Motion Picture Screening Test for the identification of perceptual disabilities in 360 rural Appalachian fourth grade children. Results indicated that test scores are related to achievement, and children scoring in the bottom 5% exhibited deficiencies in perceptual development. The test can be easily administered in a group situation at minimal cost.

Evaluation of Two Instrumental Procedures for Use with Embedded-Figures Subtest of Purdue Motion-Picture Screening Test

1976 ◽  
Vol 42 (1) ◽  
pp. 133-134 ◽  
Author(s):  
Jerry B. Ayers ◽  
Michael E. Rohr
Keyword(s):  
Reading Achievement ◽  
Motion Picture ◽  
Test Scores ◽  
Screening Test ◽  
Achievement Test ◽  
Second Grade ◽  
Embedded Figures ◽  
Total Performance ◽  
Materials Used ◽  
Screening Device

The purpose of this study was to determine if modification of the materials used by young Ss in responding affected their performance on a motion picture screening device. Modification of the modes of measuring responses increased the total performance of 24 kindergarten Ss; however, there appeared to be little relationship with standardized reading achievement test scores for first and second grade Ss. The approaches used appeared applicable with kindergarten Ss.

Distortion, Fill and Noise Effects on Pattern Discrimination

1966 ◽  
Vol 8 (2) ◽  
pp. 147-155
Author(s):  
Raymond B. Webster
Keyword(s):  
Intertrial Interval ◽  
Response Times ◽  
Pattern Discrimination ◽  
Stimulus Presentation ◽  
Basic Pattern ◽  
Male And Female ◽  
Noise Effects ◽  
Presentation Time ◽  
Four Levels ◽  
Method Of Constant Stimuli

This study was conducted in order to investigate the effects of distortion, fill and noise effects on pattern discrimination. Patterns were generated from a 10 × 10 matrix on a random basis and were comprised of black filled squares. There were four levels of pattern fill or complexity. Distortion was the random displacement of basic pattern elements while noise was the filling in of additionally selected (on a random basis) pattern elements. One hundred and forty-four male and female undergraduates served as the subjects. Patterns were projected automatically with a stimulus presentation time of 3.0-sec. and a constant intertrial interval of 5.0-sec. The method of constant stimuli was employed. The results indicated that the discrimination of patterns, as generated in this study, were significantly effected by fill, noise, and distortion at the 0.01 level. Interaction effects were significant also at the same level. Response times were also significantly affected as a function of fill and noise.

Special Education Screening System: Group Achievement Test

1988 ◽  
Vol 55 (1) ◽  
pp. 71-75 ◽  
Author(s):  
Brian Stone ◽  
Bert P. Cundick ◽  
Dave Swanson
Keyword(s):  
Special Education ◽  
Elementary Schools ◽  
Achievement Test ◽  
Achievement Testing ◽  
Education Students ◽  
Education Programs ◽  
Stanford Achievement Test ◽  
Special Education Programs ◽  
Screening Device ◽  
Special Education Screening

The purpose of this study was to assess the efficacy of standardized group achievement testing in screening and identifying mildly handicapped students for referral to special education programs. Stanford Achievement Test scores of students already placed in either regular or special education programs in four elementary schools were arranged according to four cutoff points: 20th, 15th, 10th, and 5th percentiles. At the 10th percentile cutoff, 71% of the special education and 97% of the regular education students were correctly identified. These results were cross-validated for students at two other elementary schools. The potential uses of this identification method as a preliminary screening device are discussed—particularly at a lower cutoff point of the 5th percentile.

scholarly journals The rapid synthesis of integral stimuli

2021 ◽  
Author(s):  
Andy Wills ◽  
Charlotte E R Edmunds ◽  
Fraser Milton
Keyword(s):  
Time Pressure ◽  
Stimulus Presentation ◽  
Rapid Synthesis ◽  
Single Dimension ◽  
Combination Theory ◽  
Presentation Time

Integral stimuli (e.g. colours varying in saturation and brightness) are classically considered to be processed holistically (i.e. as undifferentiated stimulus wholes); people analyze such stimuli into their consistent dimensions only with substantial time, effort, training, or instruction (Foard & Kemler Nelson, 1984). In contrast, Combination Theory (Wills et al., 2015) argues that the dimensions of integral stimuli are quickly combined. Through an investigation of the effects of time pressure, we support Combination Theory over the classical holistic-to-analytic account. Specifically, using colored squares varying in saturation and brightness, we demonstrate that the prevalence of single-dimension classification increases as stimulus presentation time is reduced. We conclude that integral stimuli are not slowly analyzed, they are quickly synthesized.

scholarly journals Eye Movement Dynamics Differ between Encoding and Recognition of Faces

Vision ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 9 ◽  
Author(s):  
Joseph M. Arizpe ◽  
Danielle L. Noles ◽  
Jack W. Tsao ◽  
Annie W.-Y. Chan
Keyword(s):  
Eye Movements ◽  
Recognition Performance ◽  
Spatial Dynamics ◽  
Stimulus Presentation ◽  
Study Phase ◽  
Facial Identity ◽  
Movement Dynamics ◽  
Presentation Time ◽  
Optimal Encoding ◽  
Feature Information

Facial recognition is widely thought to involve a holistic perceptual process, and optimal recognition performance can be rapidly achieved within two fixations. However, is facial identity encoding likewise holistic and rapid, and how do gaze dynamics during encoding relate to recognition? While having eye movements tracked, participants completed an encoding (“study”) phase and subsequent recognition (“test”) phase, each divided into blocks of one- or five-second stimulus presentation time conditions to distinguish the influences of experimental phase (encoding/recognition) and stimulus presentation time (short/long). Within the first two fixations, several differences between encoding and recognition were evident in the temporal and spatial dynamics of the eye-movements. Most importantly, in behavior, the long study phase presentation time alone caused improved recognition performance (i.e., longer time at recognition did not improve performance), revealing that encoding is not as rapid as recognition, since longer sequences of eye-movements are functionally required to achieve optimal encoding than to achieve optimal recognition. Together, these results are inconsistent with a scan path replay hypothesis. Rather, feature information seems to have been gradually integrated over many fixations during encoding, enabling recognition that could subsequently occur rapidly and holistically within a small number of fixations.

Indicating the Singular Point in First-Order Optical Flow Fields

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 80-80
Author(s):  
A M L Kappers ◽  
S F Te Pas ◽  
J J Koenderink ◽  
J Dentener
Keyword(s):  
Singular Point ◽  
Flow Field ◽  
Optical Flow ◽  
Stimulus Presentation ◽  
Singular Points ◽  
First Order ◽  
Optical Flow Field ◽  
Visible Part ◽  
Presentation Time ◽  
Random Dot Patterns

We investigated the accuracy with which subjects can indicate the singular point in a first-order optical flow field. This singular point might be important in navigation and orientation. The stimuli were expanding or rotating sparse random-dot patterns consisting of 80 dark dots on a light background. The stimulus window was circular with a diameter of 20 deg arc. The singular point could be at one of 48 different locations. Subjects had to indicate the location of this singular point with a cursor, while fixating in the centre of the stimulus. Presentation time was unlimited, though each dot had a limited lifetime (114 ms) to avoid density cues. Both veridicality and reproducibility for our subjects increased with increasing values of expansion or rotation in a nonlinear way. We did not find any systematic differences between expansion and rotation. When we blocked either the outer rim or the central part of the stimulus, performance remained the same for singular points that were within the visible part of the stimulus. For singular points outside this visible part, the reproducibility also remained the same, but subjects tended to locate the singular points closer to the rim of the visible part of the stimulus.

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