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951.
The statistical and structural characteristics of 13 matrices of random numbers in which both the cells and the entries were randomly chosen are discussed. Each matrix was explored considering row means, standard deviations, and correlations as well as column means, standard deviations, and correlations. A study concerning the sequential arrangement of digits was performed by finding out in tables of random numbers how many times the values 0 to 9 are followed by any other digit. Analyses indicate clear factor structures when factor analyzing correlations of rows and of columns and when examining sequential arrangements, concluding that for a given set of digits it is possible to assert both randomness and nonrandomness depending on how the data are examined.  相似文献   
952.
By showing that transitions may be obviated by recruiting degrees of freedom in the coupled pendulum paradigm, the authors reveal a novel mechanism for coordinative flexibility. In Experiment 1, participants swung pairs of unconstrained pendulums in 2 planes of motion (sagittal and frontal) at 8 movement frequencies starting from either an in-phase or antiphase mode. Few transitions were observed. Measures of spatial trajectory showed recruitment effects tied to the stability of the initial coordinative pattern. When the motion of the pendulums was physically restricted to a single plane in Experiment 2, transitions were more common, indicating that recruitment delays--or even eliminates--transitions. Such recruitment complements transitions as a source of coordinative flexibility and is incorporated in a simple extension of the Haken-Kelso-Bunz (1985) model.  相似文献   
953.
Spasmophilia is a relatively unknown condition characterized by perturbations of the neuromuscular system. We hypothesized that spasmophilia may negatively affect neuromotor functions in subtle ways. Three tests including tremor, rapid pointing movements, and alternating movements were quantified in a group of subjects with spasmophilia symptoms (SS) (n = 10) and a healthy control group (n = 10). Most of the characteristics used to evaluate motor functions in these three tests revealed no significant differences between the two groups except for two characteristics in alternating movements and two characteristics in rapid pointing movements. In terms of variances, a dissociation between voluntary movements and involuntary movements was observed for the two groups. Control subjects had significantly higher variances in involuntary movements such as tremor, while subjects with SS had significantly higher variances in voluntary movements such as alternating and rapid pointing movements. A significant increase in asymmetry in hand laterality was also noted for some characteristics in subjects with SS.  相似文献   
954.
Faces are one of the most salient classes of stimuli involved in social communication. Three experiments compared face-recognition abilities in chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta). In the face-matching task, the chimpanzees matched identical photographs of conspecifics' faces on Trial 1, and the rhesus monkeys did the same after 4 generalization trials. In the individual-recognition task, the chimpanzees matched 2 different photographs of the same individual after 2 trials, and the rhesus monkeys generalized in fewer than 6 trials. The feature-masking task showed that the eyes were the most important cue for individual recognition. Thus, chimpanzees and rhesus monkeys are able to use facial cues to discriminate unfamiliar conspecifics. Although the rhesus monkeys required many trials to learn the tasks, this is not evidence that faces are not as important social stimuli for them as for the chimpanzees.  相似文献   
955.
956.
The paper introduces a new model of argumentation, the Mixed Game Model, that no longer separates rule-governed competence from actual performance but starts from human beings and their ability of competence-in-performance. Human beings are able to orientate themselves in ever-changing surroundings and to negotiate diverging views in argumentative action games. Argumentation is thus described as a mixed game played by human beings according to principles of probability. These principles include constitutive, regulative and executive principles. Constitutive Principles focus on the basic components of the game, that is, action, dialogue, and coherence as the interplay of different communicative means. Regulative Principles mediate between correlated human abilities and interests. Executive Principles guide the sequencing of action according to cognitive strategies. The mixed game no longer rests on pre-established harmony but describes performance as a non-equilibrial process of negotiation that mediates between order and disorder and is based on the integration of various parameters such as rationality, reason, persuasion and emotion. How the model works is exemplified by an analysis of part of a debate in the European Parliament.  相似文献   
957.
Cognitive scientists were not quick to embrace the functional neuroimaging technologies that emerged during the late 20th century. In this new century, cognitive scientists continue to question, not unreasonably, the relevance of functional neuroimaging investigations that fail to address questions of interest to cognitive science. However, some ultra-cognitive scientists assert that these experiments can never be of relevance to the study of cognition. Their reasoning reflects an adherence to a functionalist philosophy that arbitrarily and purposefully distinguishes mental information-processing systems from brain or brain-like operations. This article addresses whether data from properly conducted functional neuroimaging studies can inform and subsequently constrain the assumptions of theoretical cognitive models. The article commences with a focus upon the functionalist philosophy espoused by the ultra-cognitive scientists, contrasting it with the materialist philosophy that motivates both cognitive neuroimaging investigations and connectionist modelling of cognitive systems. Connectionism and cognitive neuroimaging share many features, including an emphasis on unified cognitive and neural models of systems that combine localist and distributed representations. The utility of designing cognitive neuroimaging studies to test (primarily) connectionist models of cognitive phenomena is illustrated using data from functional magnetic resonance imaging (fMRI) investigations of language production and episodic memory.  相似文献   
958.
Pharmacotherapy follow-up (PTF) is the professional practice in which the pharmacist takes charge of the needs of the patients related to their drugs. OBJECTIVE: To validate a questionnaire to measure the ASE psychosocial determinants (attitude, social influence, self-efficacy) of PTF and the Prochaska & DiClemente's stage of change in Spanish community pharmacists. METHOD: Postal survey to 482 Asturian community pharmacists (test and retest). Validity was estimated in 134 pharmacists answering the test. Stability was estimated in 85 pharmacists answering the test and retest. Exploratory factorial analysis was used to investigate construct validity and produced 4 factors and 104 items. Those factors had high reliability (Cronbach's a between 0,87 and 0,96). DISCRIMINANT VALIDITY: Pharmacists in extreme stages of change showed significant differences of attitude, motivation and self-efficacy. Repeatability was good and the questionnaire appears valid and reliable.  相似文献   
959.
Effect of manipulating the risetime of an acoustic stimulus on two protective reflexes: cardiac defense and motor startle. The risetime is a parametric characteristic of the eliciting stimulus frequently used to differentiate among psychophysiological reflexes. The aim of the present study was to examine the effect of manipulating the risetime of an acoustic stimulus on two protective reflexes: cardiac defense and motor startle. 100 participants underwent a psychophysiological reactivity test to five presentations of an intense acoustic stimulus (105 dB white noise) under one of five risetime conditions: 0, 24, 48, 96, and 240 ms. Total energy of the stimulus was controlled by increasing the base duration of the stimulus (1000 ms) by one third of the risetime. Results showed that risetime significantly affected motor startle but not cardiac defense. Startle amplitude decreased linearly with increasing risetime after 24 ms. On the other hand, repetition of the stimulus significantly affected cardiac defense but not motor startle. These results question the traditional differentiation between startle and defense based on risetime.  相似文献   
960.
A purported replication by P. G. Roma, A. Silberberg, A. M. Ruggiero, and S. J. Suomi of the authors' previous study claims to contradict their finding that capuchin monkeys (Cebus apella) refuse to exchange with an experimenter if their partner receives a superior reward. Roma et al. used no exchange task, however, or any other task. Roma et al. offered frustration as explanation of their findings, yet failed to statistically prove that the effect of frustration is stronger than that of inequity. They also misrepresented the dependent measure of the authors' study. Reanalysis of the authors' own data indicated no role of frustration, that is, no effect of previous experience with a superior reward. The authors conclude that Roma et al.'s study is not a replication and does not disprove the authors' findings.  相似文献   
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