Differential reactions of virtual actors and observers to the triggering and interruption of psychological momentum

The present study compared virtual actors’ and observers’ perceptions of positive and negative psychological momentum (PM) and their responses to sudden interruptions of momentum. Participants with experience playing competitive table tennis imagined that they were playing a table tennis game (virtual actors), whereas participants who lacked experience playing competitive table tennis imagined that they were observing a table tennis game (observers). While viewing an audiovisual simulation of a table tennis match, participants were exposed to either an ascending (i.e., positive momentum) or descending (i.e., negative momentum) scoring sequence that was either suddenly interrupted or not interrupted at all. Participants’ PM perceptions were measured at the conclusion of the simulation. Results indicated that observers’ PM perceptions were lower than were virtual actors’ following the negative momentum sequence. More generally, interrupting positive momentum lowered PM perceptions, whereas interrupting negative momentum increased PM perceptions. Implications for the study of PM in sport are discussed.     

Learning conceptual rules: III. Processes contributing to rule difficulty

Eight unique bidimensional conceptual rule forms were compared in a rule learning paradigm. It was predicted that rule difficulty order and error distributions across stimulus class defined by a truth table would be a function of Ss' preexperimental experience predominantly with conjunctive concepts. The hypothesis stated specifically that loci of difficulty with rules derive from: (a) assignment of TT stimuli (those with both relevant attributes) to the negative category; (b) assignment of FF stimuli (those with neither relevant attributes) to the positive category; (c) assignment of TT and FF stimuli to the same category. The main effects of rule and truth table class and the interaction of rule and truth table class were statistically significant. The results confirm all predictions about rule order and error distributions.     

Assessing the Predictive Accuracy of hMLH1 and hMSH2 Mutation Probability Models

Hereditary nonpolyposis colorectal cancer (HNPCC) is characterized by a susceptibility to colorectal and extra-colonic cancers. Several guidelines exist for the identification of families suspected of having HNPCC, however these guidelines lack adequate sensitivity and specificity. In an attempt to improve accuracy for the detection of individuals with HNPCC, the Wijnen pre-test probability model (1998) and Myriad Genetics Laboratory prevalence table (2004) were developed. Here we evaluate the Wijnen model and Myriad table at predicting the presence of a mutation in individuals undergoing genetic testing for HNPCC. Forty-nine patients who had undergone genetic testing for germline mutations in hMLH1 and/or hMSH2 were part of our analysis. Our results revealed that the revised Bethesda guidelines performed with the highest sensitivity for germline mutations (94.4%), however the specificity was low (12.9%). Using a 10.0% mutation probability threshold, the Wijnen model and Myriad table had sensitivities of 55.6 and 60.0%, respectively and specificities of 54.8 and 23.8%, respectively. The Wijnen model and Myriad table were poor predictors of mutation prevalence, which is shown by the areas underneath their corresponding receiver operator characteristic curves (0.616 and 0.400, respectively). The results of this study demonsrate that neither the Wijnen model nor the Myriad table are sensitive or specific enough to be used as the only indication when to offer genetic testing for HNPCC.     

Influencer les jugements de l'adversaire au cours des interactions sportives compétitives : un exemple en tennis de table

This study analysed the masking activity of table tennis players, and any activity attempting to influence opponent's perceptions. We studied the activity of five French table tennis players during national matches in reference to the course of action theory (Theureau, 1992). Matches were videotaped, and the players' verbalizations as they viewed the tapes were collected a posteriori. The data were analysed by 1) transcribing the players' actions and verbalizations, 2) decomposing their activity into elementary units of meaning, and 3) analysing the meaningful structures of the course of action. The results showed that a large part of the table tennis players activity attempts to influence opponent's judgments. This activity aims to 1) modify the opponent's emotional experience, and 2) influence the opponent's perception of adversarial relationship. It is expressed through strokes and behaviors not related to the game. Our results lead to a new perspective of table tennis matches analysis in term of collective activity and “shared context” (Salembier and Zouinar, 2004).     

Alternatives to a table of criterion values in signal detection theory

Gardner, Dalsing, Reyes, and Brake (1984) supplied a table of criterion values (β) related to hit and false-alarm rates in signal detection theory. Other methods of calculatingβ are suggested as more accurate alternatives to using that table. A short computer program is provided to calculate β and the sensitivity indexd’.     

Sharing and Confronting Propositions in Collaborative Inquiry Learning

This study investigates how collaborative knowledge construction within an inquiry learning environment can be assisted with scaffolds that aim to support students' hypothesis generation process. Sixty-six students on a university preparatory track worked collaboratively on a kinematics task. The instructional goal was to develop students' understanding of one-dimensional kinematics. All students completed a proposition test in which they indicated their individual opinions about the truth-value of specific propositions. Subsequently, students were coupled into dyads and assigned to one of three conditions: (a) a shared proposition scratchpad (expression builder), (b) a shared proposition table, and (c) a control condition. Students in the scratchpad condition were given an expression builder consisting of dropdown menus with pre-defined variables and relations. Students in the shared proposition table condition could combine individual opinions about the truth-value of a proposition into one shared proposition table that highlighted differences in opinion. Students in the control condition received no extra support related to propositions. Learning outcomes were assessed using a variety of pre- and posttests. The findings indicate that students supported with the shared proposition table showed significant gains for qualitative knowledge about relations. The number of unique propositions students discussed during the learning session was a significant predictor of learning gains. A more detailed analysis of students' interaction protocols suggests that students differed in their task perceptions, their interaction patterns, and their use of prior knowledge.     

A TABLE OF EXPECTED STRESS VALUES FOR RANDOM RANKINGS IN NONMETRIC MULTIDIMENSIONAL SCALING

The results of applying a nonmetric multidimensional scaling algorithm to sets of pseudo random data are used as the basis for constructing, by means of regression techniques, a table which will assist a user to decide whether empirically obtained data sets are the result of a random process. The table covers the range from 12 to 48 objects (points) for one to five recovered dimensions.     

Additional rules for the transformed up-down method in psychophysics

In a classic paper, Levitt (1971) described an adaptive procedure for estimating points on the psychometric function known as thetransformed up-down method. Levitt discussed the assumptions of the method and presented a brief table with simple rules that converge to a few different points on the psychometric function. Levitt’s original table contains only the simplest rules, and sparsely covers the range of the psychometric function. This paper provides a table with previously unpublished rules which cover the range of the psychometric function at 5% intervals. There is a brief review of the major issues in adaptive testing. Technical issues such as the mean length and logical construction of the new rules are discussed.     

Objective spatial coding by 6.5-month-old infants in a visual dishabituation task

Forty 6.5-month-old infants were tested in a visual dishabituation variation of Bremner and Bryant’s reaching task used to evaluate the spatial representations of infants. In the visual dishabituation version of this task, infants were habituated to a display in which an object held a constant position at a corner of the table. Following habituation, the object was either moved to the opposite table-corner or nothing on the table was changed. Also, the infant either remained in her starting position or she moved to the opposite side of the table. The results show that, following habituation to an object, infants dishabituated to a change in the actual location of an object and not to a change in the egocentric relationship between the infant and the object. We conclude that even in a landmark-free environment (1) 6.5-month-old infants are capable of representing space allocentrically, and (2) they have the ability to update their location during passive movement.     

Orientational manoeuvres in the dark: dissociating allocentric and egocentric influences on spatial memory

Subjects in a darkroom saw an array of five phosphorescent objects on a circular table and, after a short delay, indicated which object had been moved. During the delay the subject, the table or a phosphorescent landmark external to the array was moved (a rotation about the centre of the table) either alone or together. The subject then had to indicate which one of the five objects had been moved. A fully factorial design was used to detect the use of three types of representations of object location: (i) visual snapshots; (ii) egocentric representations updated by self-motion; and (iii) representations relative to the external cue. Improved performance was seen whenever the test array was oriented consistently with any of these stored representations. The influence of representations (i) and (ii) replicates previous work. The influence of representation (iii) is a novel finding which implies that allocentric representations play a role in spatial memory, even over short distances and times. The effect of the external cue was greater when initially experienced as stable. Females out-performed males except when the array was consistent with self-motion but not visual snapshots. These results enable a simple egocentric model of spatial memory to be extended to address large-scale navigation, including the effects of allocentric knowledge, landmark stability and gender.     

Truth table tasks: Irrelevance and cognitive ability

Two types of truth table task are used to examine people's mental representation of conditionals. In two within-participants experiments, participants either receive the same task-type twice (Experiment 1) or are presented successively with both a possibilities task and a truth task (Experiment 2). Experiment 3 examines how people interpret the three-option possibilities task and whether they have a clear understanding of it. The present study aims to examine, for both task-types, how participants' cognitive ability relates to the classification of the truth table cases as irrelevant, and their consistency in doing so. Looking at the answer patterns, participants' cognitive ability influences their classification of the truth table cases: A positive correlation exists between cognitive ability and the number of false-antecedent cases classified as “irrelevant”, both in the possibilities task and the truth task. This favours a suppositional representation of conditionals.     

An alternative for judging confusability of visual letters.

Numerical values for shared distinctive features were derived from Gibson's (1) feature analysis of the 26 uppercase alphabet letters. Due to the lack of agreement among the empirical matrices, it is proposed that this more general table is a useful and practical approach for judging confusability of visual letters for uppercase items. Reaction time data from a Posner-type of letter-matching task support the effectiveness of the table for judging visual confusability among uppercase letters.     

Reaching while walking: Reaching distance costs more than walking distance

Surprisingly little is known about how people plan and control everyday physical actions, such as walking along and picking up objects. In order to explore this topic, we conducted an experiment in which university students were asked to pick up a common object (a child’s beach bucket) that stood on a table several meters from the participant’s start position. The bucket stood either on the left side, in the middle, or on the right side of the table and, depending on instructions, was to be carried to a farther target whose horizontal position was also varied. The questions were which side of the table the participant would walk along when picking up the bucket and which hand the participant would use to pick up and carry the bucket. Participants, most of whom were righthanded, preferred to walk along the left side of the table and to pick up the bucket with the right hand, although they departed from that preference when the reaching distance across the table was uncomfortable or if the target was too far to the right. The data were well fit with a mathematical model that included a right-hand bias and an estimate of functional distance that expressed the cost of reaching over some distance as approximately twice the cost of walking over the same distance.     

Machine short-cuts in the computation of chisquare and the contingency coefficient

Rapid computational routines are presented for calculatingx ² from frequency data in the following cases: (1) test of goodness of fit between an observed and a theoretical distribution; (2) test of independence of distributions displayed in anr ×c table; (3) test of independence of distributions displayed in anr × 2 table. A rapid method of computing the contingency coefficient also follows from the procedure used in the second of these cases.     

Importance of head movements in gaze tracking during table tennis forehand stroke

The purpose of this study was to clarify the properties of gaze and head movements during forehand stroke in table tennis. Collegiate table tennis players (n = 12) conducted forehand strokes toward a ball launched by a skilled experimenter. A total of ten trials were conducted for the experimental task. Horizontal and vertical movements of the ball, gaze, head and eye were analyzed from the image recorded by an eye tracking device. The results showed that participants did not always keep their gaze and head position on the ball throughout the entire ball path. Our results indicate that table tennis players tend to gaze at the ball in the initial ball-tracking phase. Furthermore, there was a significant negative correlation between eye and head position especially in the vertical direction. This result suggests that horizontal VOR is suppressed more than vertical VOR in ball-tracking during table tennis forehand stroke. Finally, multiple regression analysis showed that the effect of head position to gaze position was significantly higher than that of eye position. This result indicates that gaze position during forehand stroke could be associated with head position rather than eye position. Taken together, head movements may play an important role in maintaining the ball in a constant egocentric direction in table tennis forehand stroke.     

One more datum on Rorschach form quality

The central purpose of this work is to examine to what extent Form Quality (FQ) scoring of Rorschach responses, using Exner's (2003) Table A, is the reason for lower FQ to often be found in normative data outside the United States. The Rorschach protocols of 180 Portuguese boys and girls between 6 and 10 years of age were codified with respect to Form Quality in accordance with Exner's table of objects classified as ordinary, unusual, and minus, based on frequencies seen among U.S. adults and on an analogous Portuguese table (Table P) constructed from the protocols of 400 nonpatient children. Mean differences between the various FQ variables of the 2 tables were found to be insignificant. However, use of Janson's (2003) iota coefficient to evaluate agreement between the 2 approaches to scoring on the same protocols revealed that the more striking differences occurred in the FQu variable when agreement was assessed on the basis of each individual response. In view of these results, the authors recognize the possibility of Rorschach normative data to be universally applied, but still consider the possible advantage of each country or culture to build its own FQ table that will permit preservation of its particularities.     

How perception impacts on drawings

In 3 experiments the authors investigate how errors in perception produce errors in drawings. In Experiment 1, when Shepard stimuli were shown as a pair of tables, participants made severe errors in trying to adjust 1 part of the stimulus to match the other. When the table legs were removed, revealing a pair of parallelograms with minimal perspective cues, the illusion was weaker. The authors predicted that participants would err when drawing the table but not the parallelogram stimuli. The results of Experiment 2 support the prediction and establish a direct link between degree of perceptual distortion of the table stimuli and the severity of error in drawing. When drawing only the right-hand part of the figure, participants also erred to a greater degree in drawing the table than the parallelogram (Experiment 3). Collectively, the results suggest that perceptual distortion is linked with errors in drawing the table stimuli.     

Silence and table manners: when environments activate norms

Two studies tested the conditions under which an environment (e.g., library, restaurant) raises the relevance of environment-specific social norms (e.g., being quiet, using table manners). As hypothesized, the relevance of such norms is raised when environments are goal relevant ("I am going there later") and when they are humanized with people or the remnants of their presence (e.g., a glass of wine on a table). Two studies show that goal-relevant environments and humanized environments raise the perceived importance of norms (Study 1) and the intention to conform to norms (Study 2). Interestingly, in both studies, these effects reach beyond norms related to the environments used in the studies.     

长期高策略性技能训练对运动员大脑白质结构的影响：一项DTI研究

目前关于运动员经验优势的脑机制还存在争议, 尤其对于涉及较多认知过程参与的高策略性技能项目运动员, 其大脑白质结构可塑性变化还需进一步探究。研究横向对比了乒乓球运动员和非运动员大脑白质纤维束的弥散张量成像数据。结果发现, 相比于非运动员, 乒乓球运动员在连接背侧和腹侧通路脑区的双侧皮质脊髓束、左侧上纵束、左侧下纵束和双侧额枕下束的各向异性值(FA)更大, 进一步分析发现, 部分腹侧通路白质纤维束FA增加的原因是径向扩散系数(RD)下降。研究结果支持了动作双通路模型。提示经过长期高策略性技能训练, 乒乓球运动员在背侧和腹侧通路上的白质纤维束结构完整性增强。     

One More Datum on Rorschach Form Quality

The central purpose of this work is to examine to what extent Form Quality (FQ) scoring of Rorschach responses, using Exner's (2003) Table A, is the reason for lower FQ to often be found in normative data outside the United States. The Rorschach protocols of 180 Portuguese boys and girls between 6 and 10 years of age were codified with respect to Form Quality in accordance with Exner's table of objects classified as ordinary, unusual, and minus, based on frequencies seen among U.S. adults and on an analogous Portuguese table (Table P) constructed from the protocols of 400 nonpatient children. Mean differences between the various FQ variables of the 2 tables were found to be insignificant. However, use of Janson's (2003) iota coefficient to evaluate agreement between the 2 approaches to scoring on the same protocols revealed that the more striking differences occurred in the FQu variable when agreement was assessed on the basis of each individual response. In view of these results, the authors recognize the possibility of Rorschach normative data to be universally applied, but still consider the possible advantage of each country or culture to build its own FQ table that will permit preservation of its particularities.