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91.
The present study investigated the use of perceptual binding processes in schizophrenic (SC) patients and matched healthy controls, by examining their performance on the recall of symmetrical (vertical, horizontal and diagonal) and asymmetrical patterns varying in length between 2 and 9 items. The results showed that, although SC patients were less accurate than controls in all conditions, both groups recalled symmetrical patterns better than asymmetrical ones. The impairment of SC patients was magnified with supra-span symmetrical arrays, and they were more likely to reproduce symmetrical patterns as asymmetrical, particularly at medium and high length levels. Hierarchical regression analyses further indicated that the between-group differences in the recall of supra-span vertical and horizontal arrays, which require a greater involvement of visual pattern processes, remained significant after removing the variance associated with performance on asymmetrical patterns, which primarily reflects intrafigural spatial processes. It is proposed that schizophrenia may be associated with a specific deficit in the formation and retrieval of the global visual images of studied patterns and in the use of the on-line information about the type of symmetry being tested to guide retrieval processes.  相似文献   
92.
93.
Automated reasoning about uncertain knowledge has many applications. One difficulty when developing such systems is the lack of a completely satisfactory integration of logic and probability. We address this problem directly. Expressive languages like higher-order logic are ideally suited for representing and reasoning about structured knowledge. Uncertain knowledge can be modeled by using graded probabilities rather than binary truth values. The main technical problem studied in this paper is the following: Given a set of sentences, each having some probability of being true, what probability should be ascribed to other (query) sentences? A natural wish-list, among others, is that the probability distribution (i) is consistent with the knowledge base, (ii) allows for a consistent inference procedure and in particular (iii) reduces to deductive logic in the limit of probabilities being 0 and 1, (iv) allows (Bayesian) inductive reasoning and (v) learning in the limit and in particular (vi) allows confirmation of universally quantified hypotheses/sentences. We translate this wish-list into technical requirements for a prior probability and show that probabilities satisfying all our criteria exist. We also give explicit constructions and several general characterizations of probabilities that satisfy some or all of the criteria and various (counter)examples. We also derive necessary and sufficient conditions for extending beliefs about finitely many sentences to suitable probabilities over all sentences, and in particular least dogmatic or least biased ones. We conclude with a brief outlook on how the developed theory might be used and approximated in autonomous reasoning agents. Our theory is a step towards a globally consistent and empirically satisfactory unification of probability and logic.  相似文献   
94.
Grapheme-color synesthetes experience color, not physically present, when viewing symbols. Synesthetes cannot remember learning these associations. Must synesthetic percepts be formed during a sensitive period? Can they form later and be consistent? What determines their nature? We tested grapheme-color synesthete, MC2, before, during and after she studied Hindi abroad. We investigated whether novel graphemes elicited synesthetic percepts, changed with familiarity, and/or benefited from phonemic information. MC2 reported color percepts to novel Devanagari and Hebrew graphemes. MC2 monitored these percepts over 6 months in a Hindi-speaking environment. MC2 and synesthete DN, reported synesthetic percepts for Armenian graphemes, or Cyrillic graphemes + phonemes over time. Synesthetes, not controls, reported color percepts for novel graphemes that gained consistency over time. Phonemic information did not enhance consistency. Thus, synesthetes can form and consolidate percepts to novel graphemes as adults. These percepts may depend on pre-existing grapheme-color relationships but they can flexibly shift with familiarity.  相似文献   
95.
Measures of test emotions other than test anxiety are lacking. In a series of six studies, we developed a multi-scale questionnaire assessing test-related joy, hope, pride, relief, anger, anxiety, shame, and hopelessness (Test Emotions Questionnaire, TEQ). Consisting of subscales measuring affective, cognitive, physiological, and motivational emotion components, the scales can be used to identify both trait and state test emotions, and are available in German- and English-language versions. Using a rational-empirical strategy of test construction, we first developed theoretical models of the component structures, antecedents, and effects of different test emotions. We then conducted two exploratory, qualitative studies on the occurrence and structures of these emotions. Finally, based on theory and our exploratory data, we constructed, analyzed, and revised the scales of the TEQ in four quantitative studies. Findings of correlational and confirmatory factor analysis indicate that the scales are reliable, structurally valid in terms of representing different test emotions and components within emotions, and externally valid in terms of correlating significantly with personality, learning, academic achievement, and perceived health problems. Many of these correlations proved to be stronger for test emotions other than anxiety, implying that test anxiety is neither the only relevant test emotion, nor necessarily the most important one.  相似文献   
96.
The biased competition theory proposes that items matching the contents of visual working memory will automatically have an advantage in the competition for attention. However, evidence for an automatic effect has been mixed, perhaps because the memory-driven attentional bias can be overcome by top-down suppression. To test this hypothesis, the Pd component of the event-related potential waveform was used as a marker of attentional suppression. While observers maintained a colour in working memory, task-irrelevant probe arrays were presented that contained an item matching the colour being held in memory. We found that the memory-matching probe elicited a Pd component, indicating that it was being actively suppressed. This result suggests that sensory inputs matching the information being held in visual working memory are automatically detected and generate an “attend-to-me” signal, but this signal can be overridden by an active suppression mechanism to prevent the actual capture of attention.  相似文献   
97.
Three experiments are reported in which the relationships between task format, item type, and strategy usage were investigated for a two-dimensional relational inference task. Contrary to past findings with linear syllogisms, it was found that parallel presentation (presenting problem statements simultaneously) did not result in any increased use of deduction rule processes compared with serial presentation (presenting problem statements individually). Instead, the results suggested that mental models were used by the majority of subjects, and that multiple models were more likely to be constructed with parallel presentation. It is proposed that, in general, multiple model construction will be more frequent for deduction tasks where the cognitive load is relatively low. Hence, contrary to suggestions by Polk and Newell (1995), reasoning in this way appears to be prevalent and highly robust—where supported by task format—even where the use of this strategy is disadvantageous.  相似文献   
98.
The present study examined the moderating role of job resources, namely, organizational trust, the quality of employees’ relationship with their manager, and the motivating potential of jobs, on the negative relationship between work engagement and voluntary absence. Employee survey results and absence records collected from the Human Resources department of a construction and consultancy organization in the United Kingdom (n = 325) showed that work engagement was negatively related to voluntary absence, as measured by the Bradford Factor. Furthermore, the results showed that organizational trust and the quality of employees’ relationships with their line managers ameliorated the negative effect of relatively low levels of engagement on voluntary absence. Theoretical and practical implications of the findings are discussed.  相似文献   
99.
We identified leaders’ achievement goals and composition of creative input as important factors that can clarify when and why leaders are receptive to, and supportive of, subordinates’ creative input. As hypothesized, in two experimental studies, we found that relative to mastery goal leaders, performance goal leaders were less receptive to subordinates’ voiced creative input. In Study 1, we further showed that image threat appraisal and learning opportunity appraisal mediated this effect. In Study 2, we demonstrated that when merely creative ideas were expressed by the subordinate, performance goal leaders responded like mastery goal leaders. However, as in Study 1, performance goal leaders were less receptive to, and less supportive of, subordinates’ creative input than mastery goal leaders when the composition of subordinates’ creative input included both problem identifications and creative ideas.  相似文献   
100.
ABSTRACT

In this study we addressed the subjective benefits of activity interventions that were designed to improve cognitive fitness in old age. Two hundred and fifty-nine women (aged 70–93 years) were randomized to participate in an exercise or a computer course or a control condition for 6 months. Subjective ratings of the perceived change of cognitive and physical fitness components were captured before, during, after the intervention interval, and at a 10-month follow-up. Positive and negative affect levels and objective cognitive fitness parameters served as possible covariates. Multilevel modeling revealed that the computer group rated memory and concentration as having improved at 4 months and again at 6 months. The exercise group, in contrast, perceived physical capacities as maintained or improved. The characteristics of the activity experience seem to determine the perceived fitness changes. We conclude that actual learning experiences improve one's self-concept of abilities.  相似文献   
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