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851.
Cortical electroencephalographic (EEG) changes induced by ethanol (4.3 and 1.4 g/kg, ip), pentobarbital (50 and 16 mg/kg), and nicotine (1.0 g/kg) were examined in long-sleep (LS) and short-sleep (SS) mice that were genetically selected for differential sleep times induced by a hypnotic dosage of ethanol. Ethanol (4.3 g/kg) caused EEG changes that paralleled the behavioral differences, whereas no differences between selected lines were observed following the activating dose (1.4 g/kg). Data support the notion that the known difference in ethanol sleep times is due not to greater SS sensitivity to ethanol activation but rather to greater LS sensitivity to ethanol hypnosis. No differences between selected lines were observed following 50 mg/kg pentobarbital, which again parallels previous behavioral data. The SS mice were more responsive to pentobarbital activation (16 mg/kg). Nicotine more severely reduced EEG power and heart rate in LS mice; a continuous iv infusion of nicotine elicited a distinct pattern of behavioral stereotypy for each selected line, with more profound motor and reflex depression in LS mice. The lines do not differ in rate of nicotine metabolism, hence they must differ in central nervous system sensitivity to nicotine. Thus, lines of mice selectively bred for differential sensitivity to ethanol also display marked differences in electrophysiological and behavioral responses to nicotine.  相似文献   
852.
Institutional breakfast-serving procedures were manipulated to assess what effect changes in that aspect of the environment would have on requests for food. During baseline, six severely retarded children were required to pick up their food trays and return to their seats. The first manipulation, delaying the giving of the food tray for 15 seconds, served as a cue to evoke meal requests by three of the six children. Two of the remaining three required a model of an appropriate meal request (i.e., “Tray, please.”) at the end of the 15-second delay before they began requesting their meals. To evoke meal requests from the sixth child, an intensive training procedure, consisting of massed trials of delay and modeling, was required. Three different probes were administered to assess generalization across the people serving the meals, across mealtimes, and across both people and mealtimes. Typically, generalized responding in these new situations could be prompted by use of the 15-second delay procedure. Functional aspects of the delay procedure and its potential usefulness for evoking speech and facilitating generalization are discussed.  相似文献   
853.
Accurate classification of new exemplars in an abstraction paradigm may be due to their similarity to old exemplars rather than to abstract category (or prototype) knowledge. In the present study, subjects received initial training on a two-category problem before being transferred to a task in which half of the exemplar-response pairs had their responses reversed while the remaining half of the pairs were unchanged. When transfer occurred with no delay and involved old exemplars, more errors occurred for changed than for unchanged pairs. This result implies the use of exemplar-specific rather than abstract category knowledge. However, when transfer was delayed by 24 or 72 h, errors occurred equally often for changed and unchanged pairs. This result suggests that exemplar-specific knowledge is no longer used. Since subjects were still able to accurately classify exemplars prior to the transfer task at these delays, some form of abstract category knowledge is implicated.  相似文献   
854.
Advanced undergraduate science majors attempted for approximately 10h each to discover the laws governing a dynamic system. The system included 27 fixed objects, some of which influenced the direction of a moving particle. At a given time, any one screen of a nine-screen matrix could be observed on a plasma display screen. Confirmatory strategies were the rule, even though half the subjects had been carefully instructed in strong inference. Falsification was counterproductive for some subjects. It seems that a firm base of inductive generalizations, supported by confirmatory research, is a prerequisite to useful implementation of a falsification strategy.  相似文献   
855.
The incidence of stuttering has always been reported to be higher in males than in females. Possible causes of the unequal sex ratio include various ascertainment biases, incomplete reporting, social role differences, X-linked inheritance, or a combination of environmental and genetic elements. Each of these factors has been examined against data collected in the large family study of stuttering, and all but one have been eliminated. Only the gene-environment interaction hypothesis can be supported by the data. Statistical analysis confirms that the sex effect in stuttering is real and supports a threshold model for the sex difference. We conclude that the possibility of differences between males and females must be considered in any etiological research in stuttering.  相似文献   
856.
Black English and Standard English grammatical sentences were presented to 122 Black and White second graders in a modified cloze task. Both race and social class differences were sampled from within a single primary school, and both Black and White experimenters were utilized. No effects due to social class were found. Black subjects did better on Black English sentences than White subjects and showed fewer errors in the direction of Standard English syntax. An analysis of hit rates and false alarm rates suggested that Black subjects were more likely to emit Black English responses than White subjects but that both groups possessed equivalent sensitivity to grammatical differences. The results are not consistent with a deficit account of Black subjects' performance or with an explanation based on different dialect systems. Rather, it appears that Black and White children may differ only in their willingness to utilize specific response systems and may possess equal comprehension abilities in both dialect systems.This research was supported in part by funds made available to Bowling Green State University by NSF Institutional Grant No. GU-3619. Some of the findings were reported at the 83rd Annual Convention of the American Psychological Association, Chicago, 1975.  相似文献   
857.
Questions concerning the relationship between self-rated adjustment and the Bem Sex-Role Inventory (BSRI) were examined in two studies. In Study I, whether sex-typing was defined by Bem's original t-test criterion or the newer median-split criterion, superior adjustment was associated with androgynous vs. traditional typing only among women, not men. Also in conflict with the androgyny position, adjustment differences among sex-types were accounted for by differences in masculinity, not in femininity or androgyny per se. The greater contribution of masculinity vs. femininity to self-rated adjustment may be exaggerated because BSRI femininity includes items which do not load on a unidimensional femininity factor. In Study II, inspection of these unrelated items suggested that they reduce the desirability of BSRI femininity, thereby reducing its relationship to adjustment. Comparisons between standard BSRI scoring and an alternative based on unidimensional subscales revealed that the alternative femininity subscale was judged to be more desirable, and it reduced the degree of difference between masculinity and femininity in their relationships to adjustment. Superior adjustment, however, was again associated with androgynous vs. traditional sex-typing only among women, and adjustment differences among sex-types were again accounted for by differences in masculinity.The authors acknowledge the assistance of the following persons who helped in the administration, scoring, or preparation of questionnaire materials: Jill Jamison, Eric Isberg, Kay Peter, Steve Zalinger, Walter Davis, James Ball, Mark Jensen, and Heidi Sanft. Correspondence should addressed to Dr. Louise Silvern, Psychology Department, University of Colorado, Boulder, Colorado 80309.  相似文献   
858.
L. Ann Geise 《Sex roles》1979,5(1):51-62
One hundred and sixty nonfiction articles and features from Ladies' Home Journal and Redbook were systematically selected and examined for their projections of the female role between 1955 and 1976. Changes found in both magazines, and particularly in Redbook, which directs itself toward younger women, paralleled a number of important societal changes. Attitudes toward female employment were found to have undergone changes during this period, as presented in magazine selections. At the same time, however, a rejection of traditional sex roles appeared decidedly less popular than a flexible consideration of nontraditional alternatives. The image of women as narrow creatures, interested only in home and family, was not supported even during the earlier years in this sample.  相似文献   
859.
Three experiments are reported which investigate the effects of attentional factors on learning set performance of children. Number of varying irrelevant dimensions, trials per problem, and age were examined. The first experiment tests with 6- and 8-year-old-children the effects of one as opposed to two varying irrelevant dimensions. An interaction between age and dimensions showed younger children to be differentially affected by the treatment conditions, two varying irrelevant dimensions being more difficult than one. There was no difference between treatments for the older children, nor between older and younger subjects receiving one varying irrelevant dimension. In the second experiment, 6- and 8-year-olds were examined on two varying irrelevant dimension problems, receiving either 4 or 12 trials per problem. Amount of exposure within-problems, affected performance with 12 trials per problem resulting in superior performance at both age levels. A third experiment tested 6-, 8-, and 10-year-old-children using one and two varying irrelevant dimension problems with 4 and 12 trials per problem. Results confirmed the finding that learning set acquisition is influenced by irrelevant dimensions and within-problems exposure, with these effects interacting with age and amount of training. These findings support the utility of applications of an attentional analysis to the learning set performance of normal children.  相似文献   
860.
Two experiments were completed allowing albino rats to choose between signaled and unsignaled reward conditions. These experiments examined the effects on preference of (1) response dependent versus response-independent reward and, (2) food pellets versus chocolate milk as the reward. All subjects preferred the signaled condition over the unsignaled condition, whether exposed to response-dependent, or to response-independent delivery of rewards. Preference was controlled most effectively by presenting both the signal itself and the correlated stimulus identifying the signaled condition. The signal presented alone (Extinction 3) controlled preference more effectively than did the stimulus correlated with the signaled condition (Extinction 2). The second experiment showed that the quality of the reinforcer (pellets and chocolate milk) did not affect preference for signaled reward since all subjects preferred the signaled condition at levels comparable to those observed in Experiment 1, with food pellets. These results, along with others, argue against species differences, response-dependency, and reinforcer quality as variables affecting the direction of preference.  相似文献   
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