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161.
Eight crows were taught to discriminate overlapping pairs of visual stimuli (A+ B-, B+ C-, C+ D-, and D+ E-). For 4 birds, the stimuli were colored cards with a circle of the same color on the reverse side whose diameter decreased from A to E (ordered feedback group). These circles were made available for comparison to potentially help the crows order the stimuli along a physical dimension. For the other 4 birds, the circles corresponding to the colored cards had the same diameter (constant feedback group). In later testing, a novel choice pair (BD) was presented. Reinforcement history involving stimuli B and D was controlled so that the reinforcement/nonreinforcement ratios for the latter would be greater than for the former. If, during the BD test, the crows chose between stimuli according to these reinforcement/nonreinforcement ratios, then they should prefer D; if they chose according to the diameter of the feedback stimuli, then they should prefer B. In the ordered feedback group, the crows strongly preferred B over D; in the constant feedback group, the crows' choice did not differ significantly from chance. These results, plus simulations using associative models, suggest that the orderability of the postchoice feedback stimuli is important for crows' transitive responding.  相似文献   
162.
A series of three experiments examined children's sensitivity to probabilistic phonotactic structure as reflected in the relative frequencies with which speech sounds occur and co-occur in American English. Children, ages 212 and 312 years, participated in a nonword repetition task that examined their sensitivity to the frequency of individual phonetic segments and to the frequency of combinations of segments. After partialling out ease of articulation and lexical variables, both groups of children repeated higher phonotactic frequency nonwords more accurately than they did low phonotactic frequency nonwords, suggesting sensitivity to phoneme frequency. In addition, sensitivity to individual phonetic segments increased with age. Finally, older children, but not younger children, were sensitive to the frequency of larger (diphone) units. These results suggest not only that young children are sensitive to fine-grained acoustic-phonetic information in the developing lexicon but also that sensitivity to all aspects of the sound structure increases over development. Implications for the acoustic nature of both developing and mature lexical representations are discussed.  相似文献   
163.
164.
McKinley NM 《Body image》2004,1(2):213-219
Fat women who endorsed fat acceptance (N=128) were recruited from Radiance Magazine. Relationships between objectified body consciousness (OBC), body esteem, and psychological well-being for the mostly European American sample were similar to those found in other samples. OBC was independently related to body esteem when weight dissatisfaction was controlled. Those who endorsed the need for social change in attitudes towards fat people had higher body esteem and self-acceptance, and lower body shame, than those who endorsed personal acceptance of body size only.  相似文献   
165.
Psychological, psychophysical and physiological research indicates that people switch between two covert attention states, local and global attention, while visually exploring complex scenes. The focus in the local attention state is on specific aspects and details of the scene, and on examining its content with greater visual detail. The focus in the global attention state is on exploring the informative and perceptually salient areas of the scene, and possibly on integrating the information contained therein. The existence of these two visual attention states, their relative prevalence and sequence in time has remained empirically untested to date. To fill this gap, we develop a psychometric model of visual covert attention that extends recent work on hidden Markov models, and we test it using eye-movement data. The model aims to describe the observed time series of saccades typically collected in eye-movement research by assuming a latent Markov process, indicative of the brain switching between global and local covert attention. We allow subjects to be in either state while exploring a stimulus visually, and to switch between them an arbitrary number of times. We relax the no-memory-property of the Markov chain. The model that we develop is estimated with MCMC methodology and calibrated on eye-movement data collected in a study of consumers' attention to print advertisements in magazines.We thank Dominique Claessens of Verify International for making the data available to us.  相似文献   
166.
Although much social science research has been conducted within American Indian and Alaska Native (AIAN) communities, relatively little research has been conducted by or for those communities. We describe an approach that facilitates the active involvement of AIAN communities in the research process, from conceptualizing the issues to be investigated to developing a research design, and from collecting, analyzing, and interpreting the data to disseminating the results. The Tribal Participatory Research (TPR) approach is consistent with recent developments in psychology that emphasize the inclusion of community members and the social construction of knowledge. We describe the foundations of the approach and present specific mechanisms that can be employed in collaborations between researchers and AIAN communities. We conclude with a discussion of the implications of the use of TPR regarding project timelines and budgets, interpretation of the data, and ultimately the relationships between tribes and researchers.  相似文献   
167.
In 1877 Thomas Barlow, a London physician, published a remarkable case of functional recovery of speech following brain damage. It involved a 10-year-old boy who had lost his speech, regained it, and lost it again before he died from a disorder that affected his heart and produced embolisms that subsequently affected other organs, including his brain. Examination of the boy's brain revealed two focal regions of softening; one that affected Broca's area and the left facial-motor area, and another, which occurred weeks later, in the homologous regions of the right hemisphere. Although Barlow was most concerned with motor deficits, others at the turn of the century began to cite this case as strong evidence that the corresponding region of the right hemisphere can take over speech functions for Broca's area on the left. Whether this case really provides good support for functional takeover or vicariation theory is critically evaluated in the light of contemporary research, including PET scan studies involving damage to Broca's speech region.  相似文献   
168.
Different types of syntactic information (word category, grammatical gender) are processed at different times during word recognition. However, it is an open issue which brain systems support these processes. In the present event-related fMRI study, subjects performed either a syntactic gender decision task on German nouns (GEN), a word category decision task (WC, nouns vs. prepositions), or a physical baseline task (BASE). Reaction times in WC were faster than in GEN, supporting earlier electrophysiological results. Relative to BASE, both syntactic tasks activated the inferior tip of BA 44. In addition, BA 45 showed activation in GEN, whereas BA 47 was activated in WC. The imaging data indicate that the inferior portion of BA 44 together with type-specific prefrontal areas supports both initial word category related and later syntactic processes.  相似文献   
169.
《圣迹图》版本初探   总被引:1,自引:0,他引:1  
多年来 ,研究孔子的专书中涉及《圣迹图》版本研究的几乎没有 ,且为之介绍的专文也难得一见。《圣迹图》有绘本、石刻本、木刻本三种类型 ,乃为画家及刻梓者出自以垂永久之思 ,以求望图而知所考据 ,入室如见其人之感受。从中国版画史的角度来看 ,《圣迹图》中孔子形象 ,为后人运用想像力 ,揣摩当时的情景 ,选取孔子生平事迹中最为人所津津乐道的难忘情节创造出来的。本文就传世的各种版本及内容作一些考证及探讨。  相似文献   
170.
This paper forms an introduction to this issue, the contents of which arose directly or indirectly from a conference in May 2001 on Corruption of scientific integrity? — The commercialisation of academic science. The introduction, in recent decades, of business culture and values into universities and research institutions is incompatible with the openness which scientific and all academic pursuit traditionally require. It has given rise to a web of problems over intellectual property and conflict of interest which has even led to corporate sponsors’ suppressing unfavourable results of clinical trials, to the detriment of patients’ health. Although there are those who see the norms of science developing to recognise the importance of instrumental science aiming at specific goals and of knowledge judged by its value in a context of application, none justifies the covert manipulation of results by vested interest.Public awareness of these problems is growing and creating a climate of opinion where they may be addressed. We suggest a way forward by the introduction of nationally and internationally-accepted guidelines for industrial collaboration which contain proper protections of the core purposes of universities and of the independence of their research. Some codes suggested for this purpose are discussed. We note that some universities are moving to adopt such codes of conduct, but argue the need for strong support from the government through its funding bodies.  相似文献   
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