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81.
82.
In two experiments, we investigated the factors that influence the perceived similarity of speech sounds at two developmental levels. Kindergartners and second graders were asked to classify nonsense words, which were related by syllable and phoneme correspondences. The results support the existence of a developmental trend toward increased attention to individual phonemic segments. Moreover, one significant factor in determining the perceived similarity of speech sounds appears to be the position of the component correspondences; attention to the beginning of utterances may have developmental priority. An unexpected finding was that the linguistic status of the unit involved in a correspondence (whether it was a syllable or a phoneme) did not seem particularly important. Apparently, the factors which contribute to the perceived similarity of speech sounds in the classification task are not identical to those which underlie performance in explicit segmentation and manipulation tasks, since in the latter sort of task, syllables are more accessible than phonemes for young children. The present task may tap a level of processing that is closer to the one entailed in word recognition and lexical access. 相似文献
83.
Two different concepts of distinguishability are often mixed up in attempts to derive in quantum mechanics the (anti)symmetry of the wave function from indistinguishability of identical particles. Some of these attempts are analyzed and shown to be defective. It is argued that, although identical particles should be considered as observationally indistinguishable in (anti)symmetric states, they may be considered to be conceptually distinguishable. These two notions of (in)distinguishability have quite different physical origins, the former one being related to observations while the latter has to do with the preparation of the system. 相似文献
84.
85.
Peter Reder 《Journal of Family Therapy》1986,8(2):139-152
The term 'multi-agency' family is preferred to 'disorganized' family. Multi-agency family systems present special problems of the relationships (a) within the family, (b) between family and professional network, (c) among members of the professional network and (d) between family, network and treatment centre to whom the family is referred. Pressures on the family and professional workers can create a locked system which prevents natural development of the family or effective problem solving by the workers. A systems approach to such problems is presented which includes consultation to the family/professional network system. 相似文献
86.
Substance P facilitation of memory: effects in an appetitively motivated learning task 总被引:1,自引:0,他引:1
K Schlesinger M A Pelleymounter J van de Kamp D L Bader J M Stewart T N Chase 《Behavioral and neural biology》1986,45(2):230-239
Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals. 相似文献
87.
Peter C. Fishburn 《Synthese》1986,67(2):361-368
Axiomatizations of ordered preference differences typically assume that preferences are ordered. However, the mere assumption that preference differences can be ordered says nothing about whether preferences themselves are ordered. Utility representations for ordered differences without ordered preferences are investigated. 相似文献
88.
Fixation point digits have been widely used in tachistoscopic laterality studies as a simple and convenient means of ensuring unihemispheric projection of stimulus materials to the hemispheres. Previous findings demonstrate that fixation digits do not influence asymmetries in recognition accuracy studies with adult Ss. Present results, comparing four conditions differing in their use of fixation digits, show that in the naming latency paradigm the requirement to remember and report fixation control digits significantly augments RVF superiority. Implications for other latency tasks are discussed. 相似文献
89.
This paper reviews the literature on scapegoating, elaborating on the underlying mechanisms before describing the process of scapegoating as it occurred in a neonatal nurse support group. Illustrative vignettes are used to discuss how scapegoating was used by group members to avoid painful feelings arising from their care of extremely ill infants. Group process is related to the stages of the group's development as feelings were addressed more directly and the need to use scapegoating as a defense decreased. 相似文献
90.
Summary Subjects were shown eight-letter pseudowords tachistoscopically and were asked to report as many letters as possible. The pseudowords, examples of either first- or fourth-order approximation to English, were printed in normal or reversed spelling and were presented in either normal of mirror-imaged letters. Finally subjects were either free to report in any order they wished, or they were instructed to report from left to right or from right to left. With normal letters, the familiarity effect was controlled by the spelling direction, not by the direction of report or the match between direction of report and spelling direction. With mirrored letters, however, order of approximation to English had no effect. The results contradict two existing theories: Mewhort's theory claims that the familiarity of fourth-order materials aids processing at a postcategorical level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and normal spelling. Wolff's theory claims that familiarity aids processing at the feature level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and reversed spelling. 相似文献