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991.
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   
992.
College students ( n = 197) voted to select a beauty queen from among six photographs equivalent in physical attractiveness, as determined by rankings of 35 students from a separate university. Half the photographs bore a desirable first-name and half were assigned an undesirable first-name. As predicted, firstname had a significant effect on physical attraction: Girls with desirable firstnames received 158 votes to 39 for those with undesirable names. These data were discussed in terms of an additive, rather than an interactive, effect, due to the nature of the task. The strength of these findings was related to the study's ecological validity.  相似文献   
993.
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   
994.
995.
Since baseline performance varies with age, diminished interference effects found with increasing age do not provide evidence for a developmental trend in distractibility unless their relationship to baseline performance is known. In the present study, baseline difficulty was varied in two speeded classification experiments to investigate whether interference effects due to irrelevant information could best be characterized by absolute or proportional decrement models. In Experiment 1, first graders, third graders, and adults sorted cards on the basis of square size, both in the presence and absence of extraneous stimulus information. In Experiment 2, first graders and adults sorted cards on the basis of the density of a regular array of dots and two kinds of irrelevant information were used. Robust interference effects were found which declined with age. Manipulating discriminability of the relevant stimulus dimension resulted in large changes in sorting time, but interference effects did not vary with baseline difficulty. These results were interpreted as strongly supporting both an absolute decrement model and a developmental trend in distractibility.  相似文献   
996.
John L. Horn 《Intelligence》1980,4(4):285-317
This article is a summary and integration of results from studies of the organization and development of human abilities. Several kinds of results are interpreted as converging toward support of theories stipulating a hierarchy of intellectual functions. Near the top of this hierarchy, most related to intelligence as this is usually conceived, are the two broad sets of abilities known as fluid intelligence (Gf) and crystallized intelligence (Gc). The major focus of the review is on the decline of Gf through the “vital years of adulthood,” from 20 to 60 years of age. Major conclusions are:1. Sensory detector functions, near the bottom of the hierarchy of intellectual capacities, decline with development through the vital years, but this kind of decline is not responsible for aging decline of the major features of fluid intelligence: keenness of sensory function is not of the sine qua non of mature expressions of human intelligence.2. Memory abilities are somewhat higher in the hierarchy of intellectual functions, and thus are more strongly related to intelligence, than are sensory detectors. With increase in time interval over which retention is required, there is increase in the relationship of memory to Gf and to decline of Gf over the vital years. Accompanying this increase is an increase in the extent to which memory is dependent upon adequacy of organization at the stage of encoding. This, in turn, reflects the adequacy of eduction of relations and correlates, which is an essential feature of Gf.3. To the extent that very short-term memory is implicated in fluid intelligence, and the decline of this, it is intimately related to either a capacity or inclination to maintain close attention under conditions of high demand for attention.4. The speed with which one obtains correct answers to difficult problems is not closely related to the number of correct answers obtained when all subjects attempt all items in fluid intelligence tests, but clerical/perpetual speed, as indicated in tasks of quickly finding a particular symbol among others or tasks of making same/different judgments, is related to aging decline of Gf. As with short-term memory, this form of intellectual speediness appears to be closely related to capacities (or inclinations) for maintaining attention, dividing attention, and holding things in mind while doing other things.5. Crystallized intelligence probably increases over the vital years. This reflects dynamic restructuring of knowledge systems. It appears that there is not only an aging increase in knowledge but also an increase in the accessibility of information, a result being that humans become more creative (in one sense) as age increases through the vital years.6. Results from multivariate cross-sectional studies of intelligence are seen to be consistent with comparable results obtained with other kinds of research strategies.  相似文献   
997.
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   
998.
999.
1000.
Summary Dichotic sequence discrimination was studied by means of a three-alternative forced-choice method. Two of the alternatives (same) consisted of a single pair of dichotic clicks with the stimulus at one ear preceding the stimulus at the other ear by a given temporal separation (e.g., R-t-L). One of the alternatives consisted of a single pair of clicks with the opposite sequence (e.g., L-t-R). The subjects' task was to discriminate between the different and the same dichotic pairs. The results indicate that discrimination is a nonmonotonic function of t, i.e., V- or U-shaped, with high levels at both short and long temporal separations (t=2 and 4 ms and t=64 and 96 ms) and with lower levels of discrimination for intermediate ts. A second experiment was performed to study the effect of continued practice by subjects trained in dichotic sequence discrimination for ts 4 and 64 ms (high discrimination levels) and for t=16 ms (low discrimination level). There was no systematic trend towards improvement over 8 blocks of 50 trials for each t. Discrimination levels of these ts did not differ between Experiments 1 and 2.Dr. Babkoff is spending the 1979–1981 academic year at the Walter Reed Army Institute of Research, Department of Military Medical Psychophysiology, Forest Glen Annex, Building 189, Washington, D.C. 20012, USAThe experiments were conducted at the Bar-Ilan University, Ramat-Gan, Israel. The authors would like to thank the Bar-Ilan Research Committee for making funds available to conduct the experimentsThis material has been reviewed by the Walter Reed Army Institute of Research, and there is no objection to its presentation and/or publication. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense  相似文献   
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