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981.
In an attempt to replicate several previous studies, a reversal design was used to assess the effects of publicly posted feedback on vehicle speed reduction. The intervention phases consisted of daily posted feedback that supplied drivers with either accurate or inaccurate information regarding the percentage of vehicles exceeding the speed limit on the road. Results from the two feedback conditions indicated no speed reduction in comparison to baseline levels. These results are discussed in light of previous studies that found strong effects for such feedback. Baseline levels of driver compliance and methodological differences may limit the effectiveness of posted feedback in reducing speeding. 相似文献
982.
José E. García-Albea Susana del Viso José M. Igoa 《Journal of psycholinguistic research》1989,18(1):145-161
From a corpus of 3,530 slips of the tongue in Spanish, a sample of 753 cases of movement errors was analyzed, comprising those tokens that could be unambiguously assigned to the major categories of anticipations, perseverations, exchanges, and shifts. The analysis was performed according to two main criteria: (a) the degree of correspondence between the linguistic elements interacting in an error, and (b) the distance between such elements in terms of the type and number of the intervening linguistic boundaries. The results of this analysis converge with those obtained in English, supporting a model of sentence planning with different levels of representation and processing. Furthermore, Spanish provides a clear case to attest the role of syllabic structure in production processes, the constraints set by word boundaries in sublexical errors, and the contribution of inflectional suffixes to the assignment of grammatical category to the root morphemes. 相似文献
983.
Jos M. F. ten Berge 《Psychometrika》1985,50(1):121-122
The purpose of this note is to show that Van den Wollenberg's method of redundancy analysis is a special case of a simultaneous linear prediction method offered by Fortier. 相似文献
984.
985.
We study some operations that may be defined using the minimum operator in the context of a Heyting algebra. Our motivation
comes from the fact that 1) already known compatible operations, such as the successor by Kuznetsov, the minimum dense by
Smetanich and the operation G by Gabbay may be defined in this way, though almost never explicitly noted in the literature; 2) defining operations in this
way is equivalent, from a logical point of view, to two clauses, one corresponding to an introduction rule and the other to
an elimination rule, thus providing a manageable way to deal with these operations. Our main result is negative: all operations
that arise turn out to be Heyting terms or the mentioned already known operations or operations interdefinable with them.
However, it should be noted that some of the operations that arise may exist even if the known operations do not. We also
study the extension of Priestley duality to Heyting algebras enriched with the new operations. 相似文献
986.
Many proposals from the analysis of social networks focused on the study of scientific collaboration have been made recently. The Small Worlds theory seems to be the most efficient to study the inner features of the scientific community. Those researches have demonstrated that small communities are based on some key individuals who connect some groups which, on the contrary, would be disconnected. One of the disadvantages from the perspective of the analysis of networks is the lack of researches of particular nodes. With the implementation of a pseudocode algorithm of Floyd, we try to avoid this. To study how a small community is formed and, as a research of one case, we observe the invisible college which is formed when connecting the fifteen most productive authors of the Journal of Personality and Social Psychology . 相似文献
987.
Transthyretin influences spatial reference memory 总被引:1,自引:0,他引:1
Sousa JC Marques F Dias-Ferreira E Cerqueira JJ Sousa N Palha JA 《Neurobiology of learning and memory》2007,88(3):381-385
Transthyretin (TTR) is a plasma and cerebrospinal fluid carrier for thyroxine and retinol, described also to sequester the amyloid beta peptide. TTR levels have been described as decreased in the cerebrospinal fluid of patients with Alzheimer's disease. In order to investigate the role of TTR in learning and memory, we studied young adult and old TTR-null 129/Sv mice for cognitive performance. In the absence of TTR, 5-month-old mice display spatial reference memory impairment when compared to age-matched wild-type mice. Interestingly, while aging in wild-type mice is associated with a worsening reference memory performance, TTR-null mice show no further impairment with increasing age. As a result, no significant differences were found in this spatial reference task in old mice. Our data show that the absence of TTR seems to accelerate the poorer cognitive performance normally associated with aging. 相似文献
988.
This study investigated how global and local perceptual processes evolve during childhood according to the meaningfulness of the stimuli. Children had to decide whether visually presented pairs of items were identical or not. Items consisted of global forms made up of local forms. Both global and local forms could represent either objects or nonobjects. In dissimilar pairs, items differed at one level (target level), while the other level included similar forms on both sides (irrelevant level). The results indicate an evolution from local preference at 4 years of age to adult-like global preference at 9 years of age. Moreover, as previously reported in adults, regardless of age, identification impaired performance when the irrelevant level was made of objects and the target level was made of nonobjects (interference). However, in younger children, this interference existed even when objects were present at all levels, suggesting that the strategy used to perform the comparison task also varied according to age. 相似文献
989.
Luis Aguado Teresa Dieguez-Risco Constantino Méndez-Bértolo Miguel A. Pozo José A. Hinojosa 《Cognitive, affective & behavioral neuroscience》2013,13(2):284-296
We studied the effect of facial expression primes on the evaluation of target words through a variant of the affective priming paradigm. In order to make the affective valence of the faces irrelevant to the task, the participants were assigned a double prime–target task in which they were unpredictably asked either to identify the gender of the face or to evaluate whether the word was pleasant or unpleasant. Behavioral and electrophysiological (event-related potential, or ERP) indices of affective priming were analyzed. Temporal and spatial versions of principal components analyses were used to detect and quantify those ERP components associated with affective priming. Although no significant behavioral priming was observed, electrophysiological indices showed a reverse priming effect, in the sense that the amplitude of the N400 was higher in response to congruent than to incongruent negative words. Moreover, a late positive potential (LPP), peaking around 700 ms, was sensitive to affective valence but not to prime–target congruency. This pattern of results is consistent with previous accounts of ERP effects in the affective priming paradigm that have linked the LPP with evaluative priming and the N400 with semantic priming. Our proposed explanation of the N400 priming effects obtained in the present study is based on two assumptions: a double check of affective stimuli in terms of valence and specific emotion content, and the differential specificities of facial expressions of positive and negative emotions. 相似文献
990.
This article begins with a guiding schema of relations among cognitive science, clinical science, and assessment technology. Emphasis is placed on stochastic modeling of cognitive processes. Basic models are adjusted so as to parsimoniously accommodate performance deviations occurring with psychopathology. Modified portions of models indicate functions affected by disorder, whereas portions remaining intact indicate spared functions. Findings from clinical cognitive science are applied to the individual case using Bayesian procedures. Methods are instantiated with respect to cognitive psychopathology of paranoid schizophrenia. The authors address observations and issues arising from this application, including integration of these methods with current assessment practices. 相似文献