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941.
Frederick V. Malmstrom Robert J. Randle John S. Bendix Robert J. Weber 《Attention, perception & psychophysics》1980,28(5):440-448
Concurrent mental activity seems to be a significant, nonvisual factor affecting the human accommodation response. Two experiments were conducted to determine the direction and magnitude of this accommodation response. Experiment 1 employed a concurrent, written backwards counting task. Experiment 2 employed a concurrent, mental imagery task of “thinking near” and “thinking far.” In both experiments, the concurrent secondary task effected a cumulative accommodative shift toward the visual far point of from .25 to .75 diopter away from a near (3.0 diopter) target. This accommodative shift was observed only in the presence of a stimulus field and not in open-loop (analogous to empty-field) conditions. In addition, a long-term instability in the open-loop method of obtaining the dark focus was observed. Similarities between this accommodative shift and the pupillary response are noted. The accommodation response is discussed in relationship to both an attention-sharing and an involuntary autonomic response model. 相似文献
942.
The variable that affect motor programming time may be studied by changing the nature of the response and measuring the subsequent changes in reaction time (RT). One notion of motor programming suggests that aiming responses with reduced target size and/or increased target amplitude require more "complex" motor programs that require longer RTs. In a series of five experiments which movement time (MT) was experimentally varied target size neither influences RT when the movement amplitude was 2 or 30 cm nor when the target sizes differed by as much as a factor of 16:1. Increasing the movement amplitude from 15 to 30 cm also had no influence on RT. Movement time, however, did affect RT, with 200-msec movements having longer RTs than 120-msec movements. Target size and movement amplitude did not appear to be factors that influence programming time or program complexity. 相似文献
943.
Klapp ST 《Journal of motor behavior》1980,12(2):169-171
The difference between the Henry "memory-drum" theory and our version is that ours includes, an additional assumption that, after programming has occurred, the resultant representation can be stored in short-term memory. Otherwise, the essential ideas are the same in the two theories. Implications of the presently available data for the distinction between the theories are discussed. Regardless of how one evaluates our added assumption, it is clear that the essential insight of the Henry theory has fared very well in the 20 years since the theory first appeared in print. 相似文献
944.
John L. Barger 《The Journal of value inquiry》1980,14(2):77-91
Conclusion The above arguments have not conclusively demonstrated the existence of value; nor have they sought to. Rather, they have focused primarily on value-language itself: what it is, what it means, and how men use it. In value-judgements, men intend to speak about reality, and not merely to manifest their feelings to influence others. The conceptual character of value-words gives them a formal objectivity lacking in mere manifestations of feeling; the meaning of value-words contains a claim to objectivity arising from the ontological claim to objectivity of value itself.These facts demonstrate conclusively that value-language differs essentially from emotive manifestations of feeling. Therefore, and in contradiction to both Ayer and Stevenson, even the most abstract of value-words can be used to form legitimate, conceptually meaningful value-judgements. As judgements, value-judgements can be true or false, not because of any factual content, but specifically as conceptually meaningful, pure value-judgements.I have deliberately restricted these investigations to consideration of language, without seriously arguing the ontology of value itself. Thereby, I have met the emotivists on their own ground. Even without demonstrating the existence of value, I have shown their analysis of value-language to be flawed. Further, I have identified a unique claim to objectivity in value-language which argues strongly in favor of the real existence of value as its ultimate foundation.For the simplest, most obvious explanation of this claim to objectivity is that it refers to value, which actually exists. That proof is logically the next step in my argument. A good place to begin would be a more careful, detailed analysis of the structure of human responses such as admiration, love, enthusiasm, etc., seeking to determine what they ontologically presuppose.
Proof of the real existence of value would demonstrate the ontological grounds for the claim to objectivity of value-language. It would show that value-language is rooted in the real world, speaking of reality as it is. This would be the last, and most important sense in which value-language is meaningful and objective.
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945.
946.
Conclusion The systems approach to niche presented herein stands as an example of the unifying potential of mathematical system theory when applied to concepts and principles of ecology. Beginning with subjective concepts from the naturalistic tradition, the niche was framed in the formalism of general system theory. So modeled, it appeared as a restriction of a more general construct, the environ. Both niches and environs are implementable in the context of ecosystem models, and with the growing ability of ecologists to construct such models, system theoretic niches and environs both should serve in the future to clarify old problems of ecology, and make it possible to raise new classes of problems. The nature of niches, always difficult conceptually for the ecologist, may now give way to further development, both theoretical and empirical. 相似文献
947.
John E. Harris 《Memory & cognition》1980,8(1):31-38
In two interview studies subjects were asked what memory aids they used and how often. In particular, the reported frequencies of use of external aids such as shopping lists and memos were compared with those of internal aids that have been investigated by psychologists, such as the method of loci. Subjects in the first study were 15 male and 15 female university students, and in the second, a group of 30 adult women, most of whom were housewives. In both studies the aids reported to be used most were external ones. However, it is pointed out that the most commonly used methods of remembering must be internal, although these are not usually considered to be aids. Some difficulties that arise in the assessment of memory in interview and questionnaire studies are discussed. 相似文献
948.
949.
Relationships between gender choices and both movement patterns and social behavior were studied in first- and second-grade boys. Three-child, structured play groups were each composed of a boy whose mother saw him as high masculine in play preference on the Games Inventory, one seen as average, and one low masculine. Behaviors rated from videotapes included gender presentation variables, (e.g., leg separation), indicators of dominance and personal comfort (e.g.,range of movements), and indicators of social skill and peer response (e.g., interaction initiations). The low masculine boys were found to be the most feminine in their gender presentation, least dominant and aggressive, and the least socially successful of the boys. The greatest difference was between the low and the high masculine boys. The average masculine boys' scores were generally intermediate,but more similar to the low masculine boys on some variables and more similar to the high masculine boys on others. These conclusions apply to a group interaction play task, but not to an initial noninteractive play task. A secondary study in which girls played with low and average masculine boys is also reported. Here it was found that low masculine boys were generally intermediate between average boys and girls on gender presentation and dominance variables, but lowest of the groups on social interaction variables.
The authors appreciate the comments of Peter Bentler and Spencer Thompson on a draft of this paper, the assistance of Laura McCain in running subjects and scoring tapes, and the expertise of Shu-Yeng Wong for computer programming. 相似文献
950.