Arm coordination symmetry and breathing effect in front crawl

This study analysed the relationships among arm coordination symmetry, motor laterality and breathing laterality during a 100-m front crawl, as a function of expertise. Ten elite swimmers (G1), 10 mid-level swimmers (G2), and 8 non-expert swimmers (G3) composed three skill groups, which were distinguished by velocity, stroke rate, stroke length, breathing frequency (BF) and the mean number of strokes between two breaths - the stroke breath (SB) - over a 100-m front crawl. Four stroke phases were identified by video analysis (catch, pull, push and recovery) and the index of coordination (IdC) measured the lag time between the propulsive phases of the two arms. The three modes of coordination are catch-up (IdC<0%), opposition (IdC=0%) and superposition (IdC>0%). The IdC was established as the mean of IdC1 and IdC2, which measured the lag time between the propulsive phases of the left and right arms, respectively. The coordination symmetry was analysed by comparing IdC1 and IdC2, and the breathing effect was studied by distinguishing IdC1 (and IdC2) with and without breathing. Motor laterality was determined by an adaptation of the Edinburgh Handedness Inventory. Breathing laterality was determined by a questionnaire and observation during the 100-m trial. Most of the front crawl swimmers showed asymmetric arm coordination, with propulsive discontinuity on one side and propulsive superposition on the other. This asymmetry was most often related to breathing laterality (a preferential breathing side for a unilateral breathing pattern) and motor laterality (arm dominance), with different profiles noted. More than the breathing laterality itself, the breathing actions of the non-expert swimmers amplified their asymmetric coordination on the breathing side. Conversely, the elite swimmers, who had higher and more stable spatial-temporal parameters (velocity and stroke lengths), a high coordination value (IdC) and lower breathing frequency (BF), managed their race better than the less proficient swimmers and their asymmetric arm coordination was not disturbed by breathing actions. By determining the dominant arm and the preferential breathing side, the coach can obtain a swimmer profile that allows both coach and swimmer to better understand and respond to excessive coordination asymmetry.     

The role of anticipation and intention in the learning of effects of self-performed actions

The anticipative learning model for acquiring action-effect relations states that the acquisition of action-effect relations depends on processes that are part of action planning, in particular the anticipation of possible effects. Experiment 1 shows that response planning is indeed crucial for the learning of response effects. In this experiment distractors (tones) were presented either during response preparation or in the time interval between response execution and the presentation of a response effect. Response-effect learning was impaired when the distractors were presented during response preparation. The finding is consistent with the assumption that the distractors impaired the anticipation of potential effects and therefore reduced effect learning. In Experiment 2 all responses had two effects. Participants were instructed to produce one of the effects. Under this condition, response-effect learning was only found for the instructed effect, not for the non-instructed effect. The two experiments thus support the view that response-effect learning is selective and depends on the anticipation of potential effects during response planning. The results are discussed in terms of a model that explains both the learning of response-effect relations and the use of these effects for action control within the same theoretical framework.     

Performance of an unpleasant task: Effects of over- vs under-payment on perception of adequacy of rewards and task attractiveness

Subjects who came to an experiment expecting to receive a moderate amount of money for performing a task were then told, either before or after performing it, that their pay would be higher than, equal to, or less than they had expected. When the actual payment was announced after the task was performed, subjects' evaluations of the task increased with the amount they were paid; however, they estimated a higher rate of pay to be appropriate if they received either more or less than they expected than if they received what they expected. When the actual payment was announced before the task was performed (and before subjects made their decision to perform it), a different pattern emerged. Subjects rated the task more attractive when they were offered either more or less than the expected amount, while their judgments of the appropriateness of the pay offered increased with the amount of the offer. Implications of the results for incentive and dissonance theories as well as self-perception and equity theories are discussed.     

The effect of negative feedback about oneself and cost of information on preferences for information about the source of this feedback

The present paper reports an experiment in which different amounts of negative self-discrepant information were induced and its effects on information seeking were tested. In addition, the monetary cost of the information available was manipulated. Subjects received fictitious intelligence test results that were negatively discrepant from their self-evaluation. They were then given the opportunity to choose among several articles containing information that either derogated intelligence tests (test-disparaging information) or argued for their validity (test-supporting information). The relative preference for test-disparaging over test-supporting information increased with feedback discrepancy up to a point, but then decreased as this discrepancy became more extreme. The relative preference in reading desirability for test-disparaging over test-supporting articles was also higher when the information cost money than when it did not. In addition, the difference between the desire for the two types of information was greater under cost than under no cost conditions, particularly at the extreme levels of feedback discrepancy.     

Philosophy and politics: On Fred Dallmayr's “Critical Encounters”

This is the slightly revised text of a paper given at the annual meetings of the Society for Phenomenology and the Human Sciences held at Duquesne University, Pittsburgh, Pennsylvania, 14 October 1989.     

Natural categorization through multiple feature learning in pigeons

Recently (Troje, Huber, Loidolt, Aust, & Fieder 1999), we found that pigeons discriminated between large sets of photorealistic frontal images of human faces on the basis of sex. This ability was predominantly based on information contained in the visual texture of those images rather than in their configural properties. The pigeons could learn the distinction even when differences of shape and average intensity were completely removed. Here, we proved more specifically the pigeons' flexibility and efficiency to utilize the class-distinguishing information contained in complex natural classes. First, we used principal component as well as discriminant function analysis in order to determine which aspects of the male and female images could support successful categorization. We then conducted various tests involving systematic transformations and reduction of the feature content to examine whether or not the pigeons' categorization behaviour comes under the control of categorylevel feature dimensions-that is, those stimulus aspects that most accurately divide the stimulus classes into the experimenter-defined categories of 'Male' and 'Female'. Enhanced classification ability in the presence of impoverished test faces that varied only along one of the first three principal components provided evidence that the pigeons used these class-distinguishing stimulus aspects as a basis for generalization to new instances.     

The influence of mood on the search for supporting versus conflicting information: dissonance reduction as a means of mood regulation?

Focusing on similarities between the mood regulation approach and dissonance theory, this article addresses the interplay between dissonance and mood by examining how individuals search for information after making a decision while under the influence of positive versus negative mood. Study 1 suggested that negative mood increased the preference for consonant over dissonant information after decisions, whereas positive mood led to a more balanced information search. In Study 2, participants in negative mood rated consonant information as more pleasant and dissonant information as more annoying than participants in positive mood. In addition, the results suggested that mood regulation processes took place. In Study 3, the findings from Study 1 were replicated with a paradigm in which higher stakes were involved.