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981.
Bond criticized the base-free measure of change proposed by Tucker, Damarin, and Messick by pointing to an incorrect derivation which is here viewed instead as a correct derivation entailing an inadequately specified tacit assumption. Bond's revision leads to estimates of the correlation between initial position and change which are negatively biased by correlated errors, whereas the original approach, with the tacit assumption properly denoted, leads to unbiased values.  相似文献   
982.
A multi-element baseline design combined with a multiple-baseline design, was used to investigate the effect of availability of materials, prizes for participation, and instruction on the leisure behavior of 14 mentally retarded women in a half-way house. A leisure program was conducted on weekday evenings, during which residents could choose to participate in any of six activities offered: puzzles, card games, clay, painting, weaving, and rug making. It was found that instruction in weaving and rug making significantly increased the percentage of residents participating in these activities, and that following instruction, prizes were not necessary to maintain high levels of participation. In contrast, prizes were more effective than mere availability of materials in maintaining participation in the other activities.  相似文献   
983.
984.
Three subjects were given extensive practice in discriminating syllables which differed in voice onset time. For these subjects, there were two major findings. First, discrimination of speech follows normal psychophysical laws: long-onset-time stimuli require larger differences than shorter ones for comparable discrimination. Second, the shape of the discrimination function for experienced subjects is more like a leaning W than an inverted V, the usual shape for naive subjects. The data support a model of speech perception with both an acoustic and a phonetic component. The phonetic component is best characterized as a prototype matching process, with the prototype including information on the simultaneity of formant onset.  相似文献   
985.
The Rokeach Value Survey was administered to two groups of Chinese students: Those residing in the People's Republic of China (P.R.C.) and those who had emigrated to the United States (U.S.A.). Results indicated that the two groups have very different value hierarchies. The traditional stereotypes, which depict the Chinese as dependent and collectivistic in nature, in contrast to the independent and individualistic Americans, were not confirmed; instead the converse appeared. P.R.C. students assigned greater importance to individualistic values, whereas the U.S.A. group deemed collectivistic values more salient. The dimension of class as a meaningful variable was discussed as a tentative explanation of the results.  相似文献   
986.
Sex-role is a product of interpersonal and intrapersonal cognitive functioning. As a result, parents play an important role in the development of their children's sex-role orientation. The aim of this research was to describe the relationship between the sex-role of adults and those of their parents as measured on the Bem Sex-Role Inventory (Bem, 1974). Inventories were completed by 24 men, 41 women, and their parents. Results show the strongest relationship for gender-consonant sex-roles for mother-daughter and father-son dyads. Findings are discussed in terms of sex-role and modeling theories.  相似文献   
987.
The objective of these experiments was to quantify the pattern of change in arterial blood pressure (BP) during a discriminative aversive classical conditioning paradigm in rat using a new “high resolution” computer analysis. Sprague-Dawley rats (n=5) were restrained in a soft, conical cloth pouch and conditioned using a 6 sec. pulsed tone (CS+) followed by a 0.5 sec. tail shock; a steady tone, never followed by shock, served as a CS-. BP peaked at 16.4±6.5 mm Hg (mean±SD) above control at 1.5±0.1 sec. after onset of CS+. This “first component” (“C1”) also occurred during CS- (12.1±3.8 mm Hg), although the magnitudes of the two were significantly (p<0.05) different. Another group of rats (n=8) was treated identically except the tones were 15 seconds long. The conditional BP response consisted of two components. C1 was reminiscent of that seen using the short tone: for CS+ a peak of 13.6±5.6 mm Hg at 1.5 sec. or, for CS-, of 10.0±4.3 at 1.3 sec. (p<0.05). In CS+ trials BP peaked again (“C2,” 7.4±2.5 mm Hg) at 8.3±1.2 sec. There was no statistically significant C2 for CS- trials, clearly demonstrating discrimination between tones. The unconditional BP response in both groups consisted of two large, closely spaced peaks in BP. Respiration was recorded in 3 additional rats. After shock delivery these subjects often showed a sudden shift between (1) a regular respiratory pattern with moderate chest excursion and (2) apneic episodes interspersed with single, deep breaths. This latter pattern was associated with large, low frequency fluctuations in BP. Continued development of the rat conditioning paradigm is especially warranted because of the ability to record sympathetic nerve activity in intact, awake subjects and the large number of readily available genetic strains, which model human pathological states.  相似文献   
988.
J S Johnson  E L Newport 《Cognition》1991,39(3):215-258
Recent studies have shown clear evidence for critical period effects for both first and second language acquisition on a broad range of learned, language-specific grammatical properties. The present studies ask whether and to what degree critical period effects can also be found for universal properties of language considered to be innate. To address this issue, native Chinese speakers who learned English as a second language were tested on the universal principle subjacency as it applies to wh-question formation in English. Subjects arrived in the U.S.A. between the ages of 4 and 38 years. They were immersed in English for a number of years (a minimum of 5) and were adults at the time of testing. Non-native performance on subjacency was found for subjects of all ages of arrival. Performance declined continuously over age of arrival until adulthood, (r = -.63). When immersion occurred as late as adulthood, performance dropped to levels slightly above chance. In all of the analyses performed, subjacency did not differ from language-specific structures in the degree or manner in which it was affected by maturation. These results suggest that whatever the nature of the endowment that allows humans to learn language, it undergoes a very broad deterioration as learners become increasingly mature.  相似文献   
989.
Developmental changes in memory source monitoring.   总被引:5,自引:0,他引:5  
Previous research suggests that children are more likely than adults to confuse memories of actions they imagined themselves performing with memories of actions they actually performed (Realization Judgments), but are not more likely to confuse memories of actions they had imagined performing with memories of actions they saw another person perform (Reality Monitoring). We approach these findings in terms of a theory about the processes by which people identify the sources of their recollections (Source Monitoring). This approach suggests that children may be more likely than adults to confuse memories from different sources whenever the sources are highly similar to one another. Experiments 1 and 2 tested this hypothesis by manipulating the perceptual and semantic similarity of two sources of information and testing 4- and 6-year-old and adult subjects' recollection of the sources of particular pieces of information. Experiment 3 tested the hypothesis that children are more likely than adults to mistakenly identify memories of things they imagined another person doing as memories of things they witnessed that person doing. The findings indicate that (a) people are more likely to confuse memories from similar than dissimilar sources, (b) source monitoring improves during the preschool and childhood years, and (c) children may be especially vulnerable to the effects of source similarity.  相似文献   
990.
The study investigated the independent and interactive effects of caffeine and expectancy on caffeine-related symptoms. High- and low-caffeine consumers were randomly assigned to either an expectancy or nonexpectancy instructional set and one of four caffeine doses. Subjects were administered the State-Trait Anxiety Inventory, (Spielberger & Gorsuch, 1970) and a Symptom Questionnaire (Christensen, White, Krietsch, & Steele, 1990) prior to and 45 min following consumption of one of the four caffeine doses. An analysis of covariance identified a significant main effect for the State-Trait Anxiety Inventory scores and significant main and interaction effects for four Symptom Questionnaire items. However, when the alpha levels were corrected for the increased probability of Type I error, using the Bonferroni procedure, these effects failed to achieve significance. These results suggest that previous reports of subjective caffeine effects are also suspect because of their failure to control for the increased probability of Type I error.  相似文献   
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