scholarly journals Bilateral Symmetry Strengthens the Perceptual Salience of Figure against Ground

Symmetry ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 225 ◽  
Author(s):  
Birgitta Dresp-Langley
Keyword(s):  
Response Times ◽  
Random Order ◽  
Bilateral Symmetry ◽  
Choice Response ◽  
Local Contrast ◽  
Contrast Polarity ◽  
Perceptual Salience ◽  
Quantitative Measurements ◽  
Choice Response Time ◽  
Axis Of Symmetry

Although symmetry has been discussed in terms of a major law of perceptual organization since the early conceptual efforts of the Gestalt school (Wertheimer, Metzger, Koffka and others), the first quantitative measurements testing for effects of symmetry on processes of Gestalt formation have seen the day only recently. In this study, a psychophysical rating study and a “foreground”-“background” choice response time experiment were run with human observers to test for effects of bilateral symmetry on the perceived strength of figure-ground in triangular Kanizsa configurations. Displays with and without bilateral symmetry, identical physically-specified-to-total contour ratio, and constant local contrast intensity within and across conditions, but variable local contrast polarity and variable orientation in the plane, were presented in a random order to human observers. Configurations with bilateral symmetry produced significantly stronger figure-ground percepts reflected by greater subjective magnitudes and consistently higher percentages of “foreground” judgments accompanied by significantly shorter response times. These effects of symmetry depend neither on the orientation of the axis of symmetry, nor on the contrast polarity of the physical inducers. It is concluded that bilateral symmetry, irrespective of orientation, significantly contributes to the, largely sign-invariant, visual mechanisms of figure-ground segregation that determine the salience of figure-ground in perceptually ambiguous configurations.

scholarly journals Double Responding: A New Constraint for Models of Speeded Decision Making

2019 ◽  
Author(s):  
Nathan J. Evans ◽  
Gilles Dutilh ◽  
Eric-Jan Wagenmakers ◽  
Han van der Maas
Keyword(s):  
Decision Making ◽  
Decision Process ◽  
Response Times ◽  
Decision Making Process ◽  
Choice Response ◽  
Evidence Accumulation ◽  
Choice Response Time ◽  
Response Time Distributions ◽  
High Level ◽  
Feed Forward Inhibition

Evidence accumulation models (EAMs) have become the dominant models of speeded decision making, which are able to decompose choices and response times into cognitive parameters that drive the decision process. Several models within the EAM framework contain fundamentally different ideas of how the decision making process operates, though previous assessments have found that these models display a high level of mimicry, which has hindered the ability of researchers to contrast these different theoretical viewpoints. Our study introduces a neglected phenomenon that we term “double responding”, which can help to further constrain these models. We show that double responding produces several interesting benchmarks, and that the predictions of different EAMs can be distinguished in standard experiment paradigms when they are constrained to account for the choice response time distributions and double responding behaviour in unison. Our findings suggest that lateral inhibition (e.g., the leaky-competing accumulator) provides models with a universal ability to make accurate predictions for these data, and that only models containing feed-forward inhibition (e.g., the diffusion model) provide poor predictions for these data regardless of the assumptions underlying how double responses are triggered. We believe that our study provides an important step forward in further constraining models of speeded decision making, though additional research on double responding is required before broad conclusions are made about which models provide the best explanation of the underlying decision-making process.

Effect of Educational Kinesiology upon Simple Response Times and Choice Response Times

1991 ◽  
Vol 73 (3) ◽  
pp. 1011-1015 ◽  
Author(s):  
Josie M. Sifft ◽  
G. C. K. Khalsa
Keyword(s):  
Response Times ◽  
Choice Task ◽  
Group Differences ◽  
Control Group ◽  
Choice Response ◽  
Simple Task ◽  
Brain Gym ◽  
Choice Response Time ◽  
Educational Kinesiology ◽  
Movement Group

The purpose of this study was to determine whether Educational Kinesiology® integration movements or repatterning in conjunction with the integration movements affect the response times of college students to a visual stimulus. Ten men and ten women were randomly assigned to each of the three conditions: control, Edu-K movement, or repatterned Edu-K movements. Each subject was pretested on simple and choice response-time tasks. Following the pretest, subjects in the control group sat quietly for 10 minutes. The movement group utilized seven Brain Gym® activities. Subjects in the repatterned group experienced Dennison's Laterality Repatterning prior to doing the same Brain Gym activities. All subjects were then retested to assess changes in performance using 30 trials of each task. Statistical analyses indicated significant differences in improvement between the groups on the 4-choice task, with the repatterned group showing greater change than the Edu-K movement-only group, who in turn showed greater improvement than the control group. The groups improved by 6%, 31/2%, and 1%, respectively. No group differences were significant on the simple task, although a similar trend was indicated. Men responded faster than women on both tasks; however, the amount of improvement was similar for both.

Accuracy versus choice response time in sound localization

1996 ◽  
Vol 49 (4) ◽  
pp. 405-417 ◽  
Author(s):  
Sharon M. Abel ◽  
P.Joy Banerjee
Keyword(s):  
Response Time ◽  
Sound Localization ◽  
Choice Response ◽  
Choice Response Time

1.2 Method of constant stimuli (Method of frequency) By the Method of Frequency the stimulus range is selected in discrete intervals so that the frequency of positive answers is distributed over the range between 1% and 99%. In general, the frequency of positive res­ ponses either for an individual or for a group, is cumulatively normally distributed over a geometric intensity continuum. The absolute odor thre­ shold can then be defined as the effective dose corresponding to an arbi­ trarily selected frequency of positive responses, ordinarily 50% : ED^: Effective dose at the 50% level. 3.1.3 Signal detection The Signal Detection principle is a determination of the relation­ ship between hits and false alarms. In determining signal detectability, a stimulus or a few stimuli are presented in random order, alternating with noise. Since sensory impressions resulting frcm the presentation of stimulus versus noise are assumed to be normally distributed over the same intensity continuum and to have the same dispersion, the index of detectability d' for p (hits) minus p (false) indicates the extent to which the two distributions overlap. 3.2 Indication of response 3.2.1 "Yes" or "no" response In the classical evaluation yes-no answers are dependent on the sub­ jects1 honesty and motivation among other factors. However, yes-no ans­ wers may be evaluated if they are presented a sufficiently large number of times alternating with blanks. 3.2.2 forced choice technique One method of controlling response perseveration and otter antici­ pation factors is to use a forced choice response indication based on two or more response categories. In the measurement of odors the panelist has to report the temporal position of positive stimuli in a series of randan blanks. If the concentration is below the threshold, the test sub­ jects will guess. As the odorant concentration will increase, the rela­ tive cumulative frequency for identification of the correct sample will be greater. In order to determine the relative odor recognition a cor­ rection must be made. 3.3 Size of stimulus intervals 3.3.1 Concentration intervals In selecting the stimulus continuum in threshold determination, the relation between just noticeable difference in relation to the intensity of stimuli is of interest. In accordance with Weber's law this quotient is assumed to be a constant. Therefore it would appear best to determine absolute thresholds on an intensity continuum in the form of a gecxnetric progression. 3.2.2 Time intervals Because of adaptation processes the exposure time until reaching a decision should be limited. Also the interval between two stimuli must be observed.

1986 ◽  
pp. 71-71
Keyword(s):  
Signal Detection ◽  
Effective Dose ◽  
Random Order ◽  
Stimulus Range ◽  
Forced Choice ◽  
Just Noticeable Difference ◽  
False Alarms ◽  
Choice Response ◽  
Temporal Position ◽  
Normally Distributed

scholarly journals Combining Visual Contrast Information with Sound Can Produce Faster Decisions

2019 ◽  
Author(s):  
Birgitta Dresp-Langley ◽  
Marie Monfouga
Keyword(s):  
Response Times ◽  
Luminance Contrast ◽  
Forced Choice ◽  
Sound Frequency ◽  
Choice Response ◽  
Relative Depth ◽  
Probability Summation ◽  
Visual Contrast ◽  
Contrast Information ◽  
The Right

Pieron's and Chocholle’s seminal psychophysical work predicts that human response time to information relative to visual contrast and/or sound frequency decreases when contrast intensity or sound frequency increases. The goal of this study is to bring to the fore the ability of individuals to use visual contrast intensity and sound frequency in combination for faster perceptual decisions of relative depth (“nearer”) in planar (2D) object configurations on the basis of physical variations in luminance contrast. Computer controlled images with two abstract patterns of varying contrast intensity, one on the left and one on the right, preceded or not by a pure tone of varying frequency, were shown to healthy young humans in controlled experimental sequences. Their task (two-alternative forced-choice) was to decide as quickly as possible which of two patterns, the left or the right one, in a given image appeared to “stand out as if it were nearer” in terms of apparent (subjective) visual depth. The results show that the combinations of varying relative visual contrast with sounds of varying frequency exploited here produced an additive effect on choice response times in terms of facilitation, where a stronger visual contrast combined with a higher sound frequency produced shorter forced-choice response times. This new effect is predicted by cross-modal audio-visual probability summation.

scholarly journals Hierarchical diffusion models for two-choice response times.

2011 ◽  
Vol 16 (1) ◽  
pp. 44-62 ◽  
Author(s):  
Joachim Vandekerckhove ◽  
Francis Tuerlinckx ◽  
Michael D. Lee
Keyword(s):  
Response Times ◽  
Diffusion Models ◽  
Choice Response ◽  
Hierarchical Diffusion
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