Symmetropy,an entropy-like measure of visual symmetry

A new objective measure of symmetry for single patterns, called symmetropy, is developed on two bases, the two-dimensional discrete Walsh transform of a pattern and the entropy concept in information theory. It is extended to a more general measure, called the symmetropy vector. In order to test the predictive power of the symmetropy vector, multiple regression analyses of judged pattern goodness and of judged pattern complexity were carried out. The analyses show that the symmetropy vector predicts pattern goodness and pattern complexity, as well as the amount of symmetry in a pattern. They also suggest that pattern goodness is a concept based on the holistic properties of a pattern, while pattern complexity (or simplicity) is a concept based on both holistic and partial properties of a pattern.     

3～5岁儿童模式认知能力发展的研究

选取北京市10所幼儿园的249名3～5岁儿童为被试,采用概括抽象程度不同的任务对儿童的模式复制和扩展能力进行个别测查。结果表明:(1)儿童早期模式认知能力发展的年龄主效应显著,性别主效应显著,年龄与性别的交互作用显著。(2)儿童模式复制能力在3 5～4 5岁之间发展较为迅速,模式扩展能力在4～5岁之间发展较为迅速。(3)儿童的模式复制能力无显著性别差异,但女孩的模式扩展能力显著高于男孩。(4)儿童的模式复制能力显著高于模式扩展能力,随着年龄的增长它们之间的差距有减小的趋势。(5)随着年龄的增长,儿童在模式复制和模式扩展任务中所犯错误水平在下降。     

Using several modalities to perceive one temporal pattern

In two experiments, subjects identified temporal patterns. The patterns consisted of eight dichotomous (left-right) elements, e.g. LLRRLRLR, continuously repeated until the subject was able to identify the pattern. In Experiment 1, one pattern was presented either separately in the auditory, tactual, or visual modalities or one pattern was presented simultaneously in two modalities (compatible presentation). In Experiment 2, one pattern was simultaneously presented in two modalities, but the pattern was presented in one modality and the complement of the pattern (the complement of LLRRLRLR is RRLLRLRL) was presented in the second modality. Therefore, opposite spatial elements appeared in each modality (incompatible presentation).

The results indicated that the rate of pattern identification was the same for compatible and incompatible presentation. These methods produce better performance than individual modality presentation at fast presentation rates (2 elements/sec. and faster) although individual modality presentation was better at slower rates. This suggests that when a pattern is presented in two modalities, the pattern in each modality is integrated, not the particular spatial elements in each modality. Furthermore, the rate of pattern identification using individual modalities did not predict the difficulty using pairs of modalities. These results demonstrate the Gestalt nature of pattern perception; the pattern is perceptually salient and the performance of pairs of modalities depends on the inherent properties of the individual modalities.     

Some observations on the perception of Marroquin patterns.

Demonstrations are presented to show that the perception of structure in Marroquin patterns is disrupted if the dots comprising the pattern have opposite contrast polarity, and also if the dots comprising the pattern are separated in stereoscopic depth. It is also demonstrated that the perception of structure in a Marroquin pattern is made possible if the pattern is separated in stereoscopic depth from 'noise' dots, where the pattern structure cannot be perceived in either half of the unfused stereogram. In these respects the perception of Marroquin patterns is similar to the perception of Glass patterns. These findings are thus consistent with the proposal that the perception both of Marroquin and of Glass patterns is based on the construction of virtual lines.     

Documenting and explaining the common AAB pattern in music and humor: establishing and breaking expectations

The AAB pattern consists of two similar events followed by a third dissimilar event. The prevalence of this pattern in the aesthetic domain may be explained as violation of expectation: A minimum of two iterations is required to establish a repetitive pattern; once established, it is most efficient to promptly violate the expected continuance of the pattern to produce the maximal aesthetic effect. We demonstrate the prevalence of this pattern (in comparison to AB or AAAB) in a representative sample of a variety of musical genres and in a representative sample of repetitive genre of jokes. We also provide experimental evidence that the AAB pattern in jokes is maximally effective in producing a humor response in participants.     

Identifying criterion-related patterns of predictor scores using multiple regression

Along with examples involving vocational interests and mathematics achievement, the authors describe a multiple regression based, pattern recognition procedure that can be used to identify a pattern of predictor scores associated with high scores on a criterion variable. This pattern is called the criterion pattern. After the criterion pattern has been identified, a second regression procedure can be used to estimate the proportion of variation attributable to the criterion pattern. Cross-validation can then be used to estimate the variation attributable to a criterion pattern derived from regression weights estimated in another sample. Finally, issues of criterion pattern invariance and interpretation are discussed.     

Binocular rivalry with rotary and radial motions

Binocular rivalry between a radially sectored and a concentrically circular pattern was investigated in three experiments. Motion of the circular pattern was either cyclical expansion and contraction with corresponding changes in spatial frequency (experiment 1), or outward motion with a constant linear velocity (experiment 2). When both patterns were static the circular pattern was visible for longer than the radial one. Motion of either pattern alone resulted in an increase in the predominance duration and the mean period for which the pattern was visible. This is at variance with Levelt's model of rivalry. In the third experiment, rivalry was between a static circular pattern and a radial pattern that could be rotated at different angular velocities. Again it was found that an increase in stimulus strength, as measured by predominance, led to an increase in the mean periods of visibility of the rotating pattern.     

Vibrotactile pattern isolation/integration

Temporal integration has been cited as a major factor in temporal masking. Two experiments were designed to examine the conditions under which temporal integration may aid or hinder the perception of vibrotactile spatial patterns. In Experiment 1, the subject’s task was to discriminate between pairs of patterns. Each pattern was composed of two temporally separated pattern elements. When the task required the subjects to perceive the individual pattern elements, performance improved with temporal isolation—that is, performance improved as the temporal separation between the elements increased. In a second task, when the discrimination could be based on either the overall pattern shape or the pattern elements, temporal integration appeared to improve performance—that is, performance improved as the temporal separation decreased. In Experiment 2, an identification task was used. Several factors appeared to determine whether temporal integration aided or hindered pattern identification. When pattern elements similar to those in Experiment 1 were tested, performance improved with increasing temporal separation (isolation). A single function was fit to the discrimination (isolation) and identification (isolation) results. Whether temporal integration aids or hinders pattern perception appears to depend on pattern shape, the pattern elements, and the nature of the task.     

The Relative Dominance of Schemata in a Manual Tracking Task: Input Patterns,System Dynamics,and Movement Patterns

As subjects repeatedly track the same spatiotemporal pattern, they learn to anticipate the pattern and thereby to reduce their effective time delay. The successive organization of perception hypothesis suggests that subjects progress from an error-nulling mode to a pursuit mode, in which they respond to the estimated instantaneous input pattern, and then to a precognitive mode, in which they rely on memory of the input pattern or movement pattern. We used a transfer of training experiment involving position and rate control systems to distinguish among these strategies by determining the relative dominance of schemata for the input pattern, system dynamics, and movement pattern. Results indicated that subjects relied on a memorized movement pattern, which is characteristic of the precognitive mode. Adaptations of this transfer methodology may be useful in testing other theories that postulate multiple schemata for the control of perceptual-motor behavior.     

Bias in proportion judgments: the cyclical power model

When participants make part-whole proportion judgments, systematic bias is commonly observed. In some studies, small proportions are overestimated and large proportions underestimated; in other studies, the reverse pattern occurs. Sometimes the bias pattern repeats cyclically with a higher frequency (e.g., overestimation of proportions less than .25 and between .5 and .75; underestimation otherwise). To account for the various bias patterns, a cyclical power model was derived from Stevens' power law. The model proposes that the amplitude of the bias pattern is determined by the Stevens exponent, beta (i.e., the stimulus continuum being judged), and that the frequency of the pattern is determined by a choice of intermediate reference points in the stimulus. When beta < 1, an over-then-under pattern is predicted; when beta > 1, the under-then-over pattern is predicted. Two experiments confirming the model's assumptions are described. A mixed-cycle version of the model is also proposed that predicts observed asymmetries in bias patterns when the set of reference points varies across trials.     

The relative dominance of schemata in a manual tracking task: input patterns, system dynamics, and movement patterns

As subjects repeatedly track the same spatiotemporal pattern, they learn to anticipate the pattern and thereby to reduce their effective time delay. The successive organization of perception hypothesis suggests that subjects progress from an error-nulling mode to a pursuit mode, in which they respond to the estimated instantaneous input pattern, and then to a precognitive mode, in which they rely on memory of the input pattern or movement pattern. We used a transfer of training experiment involving position and rate control systems to distinguish among these strategies by determining the relative dominance of schemata for the input pattern, system dynamics, and movement pattern. Results indicated that subjects relied on a memorized movement pattern, which is characteristic of the precognitive mode. Adaptations of this transfer methodology may be useful in testing other theories that postulate multiple schemata for the control of perceptual-motor behavior.     

Intentional switching between patterns of bimanual coordination depends on the intrinsic dynamics of the patterns

Two predictions arising from previous theoretical and empirical work which demonstrated that spontaneous changes of bimanual coordination patterns result from a loss of pattern stability (i.e., a nonequilibrium phase transition) were tested: (a) that the time it takes to intentionally switch from one pattern to another depends on the differential stability of the patterns themselves; and (b) that an intention, defined as an intended behavioral pattern, can change the dynamical characteristics, e.g., the overall stability of the behavioral patterns. Subjects moved both index fingers rhythmically at one of six movement frequencies while performing either an in-phase or antiphase pattern of finger coordination. On cue from an auditory signal, subjects switched from the ongoing pattern to the other pattern. The relative phase of movement between the two fingers was used to characterize the ongoing coordinative pattern. The time taken to switch between patterns, or switching time, and relative phase fluctuations were used to evaluate the modified pattern dynamics resulting from a subject's intention to change patterns. Switching from the in-phase to the antiphase pattern was significantly slower than switching in the opposite direction for all subjects. Both the mean and distribution of switching times in each direction were found to be in agreement with model predictions. movement frequency had little effect on switching time, a finding that is also consistent with the model. Relative phase fluctuations were significantly larger when moving in the antiphase pattern at the highest movement frequencies studied. The results show that, although intentional influences act to modify a coordinative pattern's intrinsic dynamics, the influence of these dynamics on the resulting behavior is always present and is particularly strong at high movement frequencies.     

Effect of practice on the perception of temporal patterns

The effect of practice on the organization and the rate of identification of temporal patterns was investigated. The patterns involved a set of eight dichotomous left-right elements, repeated without interruption until the subject was able to identify the patterns. The patterns were presented in the auditory, tactual, or visual modalities, or in pairs of these modalities. In some conditions, all the pattern elements were presented in one modality; in other conditions, four elements were presented in one modality and the remaining four elements were presented in the second modality.

The results demonstrated that when all pattern elements were presented in one modality, naive subjects organized the sequence into a well-structured pattern; practiced subjects organized the sequence into a pattern beginning at the starting element. These patterns may be poorly-structured. When four pattern elements were presented in each of two modalities, naive subjects organized the elements in each modality separately; practiced subjects disregarded the modality structure and organized the sequence into a well-structured pattern.

These changes in organization suggest a hierarchy of perceptual modes; perception by modality (i.e. by sensations) is least complex, perception by pattern structure is intermediate, and perception by start point is most complex. Changes in the rate of pattern identification confirm this hierarchy. Furthermore, the changes in organization and identification found for highly practiced patterns were also found for novel patterns.     

攻击性初中生的类别转变：潜在转变分析

研究采用潜在转变分析探讨了攻击性初中生的类别转变。276名初中参加了为期一年的短期纵向追踪研究,在一年中分两次报告了自己的攻击行为。用潜在转变模型分析了初二到初三时青少年的攻击类别转变,结果表明初中生有三种攻击模式。研究以潜在转变模型进一步探究了这三种攻击模式的变化,结果发现两种模式具有很强的稳定性,不同模式之间也有一定程度的转变。最后,研究探讨了攻击类别转变的影响因素,结果表明性别与友谊质量可以起到显著作用。针对实际意义,文章最后进行了讨论和总结。     

Aftereffect of induced rotation: number of pattern elements and area of pattern in inducing stimulus

Previous research has suggested that aftereffect of induced rotation can be longer when the number of pattern elements in the inducing stimulus is greater. This was explained by the amount of shearing between pattern elements of inducing and static stimuli. However, the results might also be explained by the greater area occupied by a greater number of pattern elements. The present experiment used three inducing stimuli, in which number of pattern elements and area of pattern were varied independently, to test between these hypotheses. The former was corroborated and the latter refuted.     

Serial pattern complexity: irregularity and hierarchy.

In perception research, various models have been designed for the encoding of, for example, visual patterns, in order to predict the human interpretation of such patterns. Each of these encoding models provides a few coding rules to obtain codes for a pattern, each code expressing regularity and hierarchy in that pattern. Some of these models employ the minimum principle which states that the human interpretation of a pattern is reflected by the simplest code for that pattern, ie the simplest code according to a given complexity metric. In this paper a new complexity metric is proposed. This metric is based on a formal analysis of the concept of regularity. Some conclusions of this analysis are sketched. The new metric does not depend on artifacts of the coding rules. It accounts for the amounts of irregularity and hierarchy as represented in a code of a pattern, such that these two amounts can be added to determine the complexity of a code. An experiment is discussed that shows that the new metric performs significantly better than the metrics used previously. In particular, the new metric predicts more local pattern organizations than the old metrics. This implies that various local pattern organizations do not falsify the minimum principle anymore.     

The aesthetic attractivity of the golden section

Summary It is hypothesized that the presence of a golden section does not in and of itself add to the aesthetic attractivity of a pattern. Only as far as the realization of a golden section entails equivalences between parts of a pattern, will the aesthetic appeal of a pattern be enhanced. An experiment is reported in which this hypothesis is tested and confirmed.     

Privileged directions for subjective contours: horizontal and vertical versus tilted

Subjective contours and brightness enhancement in Ehrenstein-like situations are affected by pattern orientation. If a classic Ehrenstein pattern (with four inducing elements for every gap at intersection points) is observed, a number of anomalous illusory patches usually appear in these gaps, but if the same pattern is observed tilted by 45 degrees the patches disappear and it is possible to see an illusory grid of horizontal and vertical 'streets'. These two perceptual results are mutually exclusive. In a Koffka-cross variant of this pattern, the illusory patches, which are usually square, appear more rounded in the tilted pattern. All these results were confirmed in two experiments by means of a magnitude estimation procedure. It is suggested that the formation of a subjective contour is easier along horizontal and vertical directions and more difficult in an oblique direction, and that this phenomenon, as well as other visual acuity oblique effects, depends in part on the basic functioning of the visual system at the level of sensation.     

Analysis of temporal suppression mechanism in binocular rivalry

A method for analyzing the temporal suppression mechanism in binocular rivalry is described. A test pattern was presented to one eye and a suppressing pattern to the other eye after varying time intervals. The subject was instructed to report the frequency of nonsuppression phases of the test pattern immediately after presentation of the suppressing pattern. Analysis indicated that the test pattern was never suppressed at the 0-msec. stimulus onset asynchrony and the nonsuppression probabilities decreased as the onset asynchrony increased. Moreover, resistivity to contralateral suppression was greater when the test pattern was projected to the dominant eye.