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981.
A feed delivery system for the study of choice behavior in cows is described. Supportive data are provided for six dairy cows exposed to two-alternative, concurrent variable-interval schedules.  相似文献   
982.
Twenty subjects judged the average lightness and darkness of paired Munsell gray papers according to magnitude estimation and category rating instructions. The data from category rating were approximately consistent with an averaging model but those from magnitude estimation were not. An analysis in terms of a two-stage model suggested that category ratings and magnitude estimates of each attribute were produced on the basis of the same composition rule, but implicated different output transformations. In judging darkness, subjects appeared to have reversed the scales employed in judging lightness, by a linear transformation in the case of category rating and by a reciprocal transformation in the case of magnitude estimation. However, differences between the input parameters obtained from judgments of lightness and darkness suggested that the scales of these attributes constructed from judgments of average magnitude may be biased.  相似文献   
983.
984.
The Problem of Fusion in the Lesbian Relationship   总被引:1,自引:0,他引:1  
This paper is an attempt to outline a set of hypotheses about the kinds of issues that intensify the problem of fusion in committed lesbian partnerships. We consider also why the likelihood is so great of fusion occurring as a response to stresses both internal and external to the relationship. We have chosen to address the problem from a systems perspective because we feel that the most productive clinical interventions for lesbian couples depend upon an awareness of the problems inherent in the couple's attempt to define the rules of their relationship within the context of a larger system in which no rules relating to them exist. We shall outline our basic conceptual approach to the problem, offer case examples of a "fused" lesbian couple, and discuss implications for treatment.  相似文献   
985.
Feedback and feedback plus points toward a course grade were applied to the attentional behaviors (defined as the ability to identify the semantic base of text passages) of 30 undergraduate students participating in a reading comprehension development program. Correct underlining was increased, extraneous underlining was decreased, and postreading comprehension test scores improved as a result of the procedures. Scores on a standardized test of reading comprehension also increased significantly.  相似文献   
986.
An energy conservation contest among four groups of apartments (44 to 70 units each) in a University of Colorado family housing complex was conducted February-April, 1977. The winning group in each of six 2-week contests won $80 to use however it determined. The program produced a drop of about 10% in use of natural gas during the first contest; energy savings were smaller but still statistically significant throughout the first 8 weeks. Over a 12-week period, savings averaged 6.6%. Some changes in energy-using behaviors were reported by residents surveyed at the contest's end; however, knowledge of contest results by residents was minimal. The results are compared to those of other contest and rebate programs, the practical problems of costs exceeding savings and inaccurate estimates of energy savings are discussed, and implications for future research are suggested.  相似文献   
987.
Two groups of 11- to 12-year-old educable mentally retarded children, equated on the basis of a free recall pretest, were given a series of lists for free recall. Approximately half the subjects were trained in the use of a strategy designed to induce deeper level semantic encoding and the discovery of categorical relationships and half constituted a “no-training” control group with standard free recall instructions. The subjects received either related or unrelated lists during the training phase and related or unrelated lists during two post-tests, immediately following and 1 week after training. There was evidence not only that the semantic strategy was maintained over the 1-week delay, but that it also generalized to word lists unlike those used during training. The degree of generalization was greater for those subjects receiving related lists during training.  相似文献   
988.
989.
Attention and saccadic eye movements   总被引:3,自引:0,他引:3  
Four threshold detection experiments addressed three issues concerning the relationship between movements of spatial attention and saccadic eye movements: (a) the time course of attention shifts wit saccades, (b) the response of the two systems to changes in stimulus parameters, and (c) the relationship of attention to saccadic suppression. These issues bear on the more general question of the degree of independence between the saccadic and attentional movement systems. The results of these experiments support the contention that the mechanisms that shift attention are separate from those that control saccadic eye movements. Relevant events in the visual field periphery, however, will trigger both a saccade and attention shift. The attentional response to such events does not appear to be under subjects' control. The implication of these results for theories of saccadic suppression is discussed.  相似文献   
990.
Left-ear superiority for perception of dichotically presented musical chords was seen in musicians at all levels of competence. However, a hypothesis that dominance would be greater in the more professional musicians was not confirmed. Whereas many of the professionals did have the largest left-ear preferences, about half had strong right-ear superiorities instead. On the average, therefore, there was no ear dominance for the two most professional groups, although the other groups had the expected left-ear dominance. Furthermore, ear differences for the professional groups were distributed only in the categories of weak to strong left- and weak to strong right-ear preferences, whereas ear differences for the other groups included also the central categories of no or little ear preference. The better musician groups were also more strongly affected by an auditory illusion in which right-ear dominance occurred when subjects reported the ear receiving the high chord, whereas left-ear dominance was seen when they reported the ear receiving the low chord (for the same dichotic pair). That is, ear dominance was dependent on instructions, switching in the same subject from left to right ear when the task changed from reporting the location of the low to reporting the location of the high chord, respectively. However, ear dominance and switching were only partially present in nonmusicians and were weak in amateurs. It may be that ear dominance for chord recognition is influenced by specialized cognitive development in musicians, on the one hand, and by noncognitive neurophysiological factors on the other.  相似文献   
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