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991.
Analysis of two chimpanzees' conversations with their teacher during a tool-use training task demonstrated that chimps use lexigrams, a humanly devised visual symbol system, selectively to encode perceived variability; that is, they generally used their symbols to differentiate alternative possibilities or to represent change or novelty in a situation. In contrast, they tended to leave unsaid what was unchanging, repetitive, or the unique possibility in a situation. Perceived variability influenced not only which symbols were selected but also utterance length: A single dimension of variability in a situation leads to single-lexigram utterances; multiple dimensions are associated with multi-lexigram utterances. This pattern of results indicates that the absence of formal grammatical structure in chimp language does not imply that utterances beyond one word in length are either rote strings or imitations. The chimps' tendency to mention the variable while leaving the constant or redundant unsaid is, moreover, strong support for the position that their use of a humanly devised symbol system is more than a series of conditioned responses.  相似文献   
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Smokers and nonsmokers were compared on three aspects of academic achievement. Although exactly the same percentage of smokers and nonsmokers passed the first-year university examination, smokers obtained significantly higher marks. Similarly, smokers achieved significantly higher marks in their final year examinations in comparison with nonsmokers. Finally, a comparison of the tutorial essay marks of the smokers and nonsmokers again showed that smokers obtained significantly higher marks than nonsmokers. These data are consistent with the idea that ambitious students adopt smoking in the belief that it will help them study and sustain concentration.  相似文献   
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In the literature on cotherapy, little attention has been focused on maximizing the effectiveness of two therapists working in tandem with families and couples. While cotherapists may at times share their ideas and feelings with their clients, and after the therapeutic session exchange views between themselves, generally little interaction occurs between them during the session. In this paper, a case is presented for more active interactions between cotherapists during the session, in order to expedite and facilitate change and growth in their clients. Anecdotal examples are provided to illustrate the approach.  相似文献   
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Kinetic subjective contours   总被引:2,自引:0,他引:2  
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