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951.
Four pigeons were trained on a multiple variable-interval 30-s extinction schedule with various pairs of spoken English words presented as the discriminative stimuli. The birds typically produced discrimination indices of 70% to 90% accuracy. Discrimination accuracy was improved by shortening the interval between auditory stimulus presentations, and by increasing the number of syllables in the words.  相似文献   
952.
This paper is a general survey of ethical issues related to the artificial heart. It begins by looking at the history of funding of the artificial heart program through the National Institute of Health in 1965. Attention is paid to the problem of the lack of planning related to social, ethical, economic, and legal implications. The paper then deals with three areas of ethical concerns. They are those issues relating to the experimental versus therapeutic benefits, the cost, and public involvement with a private interest.  相似文献   
953.
The Separation-Individuation Test of Adolescence   总被引:3,自引:0,他引:3  
The procedures undergone to establish the validity of the Separation- Individuation Test of Adolescence (SITA) are described. The test consists of six scales designed to measure key dimensions of adolescent separation-individuation. Each scale was subjected to three stages of validation: theoretical-substantive, internal-structural, and external-criterion. The results of data with 305 adolescents are reported. Although particular modifications from the original form are planned, appreciative levels of validity were established for the SITA's various scales.  相似文献   
954.
In this study, we investigated the factorial structure of the Manifest Anxiety Scale (MAS) among American, counseling graduate students (N = 227). The MAS was administered across transsituational and transtemporal conditions. The following four factors were yielded following orthogonal rotation: General Worries, Physiological Correlates of Anxiety, Distractibility, and Embarrassment. These four factors, however, explained less than one quarter of the common variance extracted. Following a comparison with previous factor analytic studies of the MAS, we discuss factors possibly contributing to the discrepant findings, with particular attention to the MAS's item content and psychometric properties and the nature of the population used.  相似文献   
955.
Recent work on orientation perception and memory in infants suggest that oblique stimulus orientations are treated as members of a category. The two studies in this report support this hypothesis and extend previous findings by demonstrating that this category includes obliques on either side of vertical even when infants are previously exposed to obliques on only one side.  相似文献   
956.
Predictions of physical symptomatology by daily life events and by major life events were compared, replicating and expanding work reported by DeLongis, Coyne, Dakof, Folkman, & Lazarus (1982). Analyses of daily, prospective data collected on 79 married men for 90 days demonstrated that daily, undesirable events were better predictors of symptom frequencies than either past, major life events or daily, desirable events. These results, similar to those found by DeLongis et al. (1982), were further explored by examining "healthy" subjects versus subjects with prior medical conditions. Undesirable daily events were a much stronger predictor of physical symptoms in the healthy group than in the prior medical conditions group.  相似文献   
957.
This study investigates the extent to which learning disabled readers' atypical encoding relates to their deficiencies in semantic memory. Inferences related to ability group performance were based on the assumption that encoding involves the matching of incoming information against a featural representation of that information in semantic memory. To this end, learning disabled and nondisabled readers in two age groups were compared on dichotic listening recall tasks that included orienting and nonorienting instructions. Orienting instructions directed children's attention toward semantic, phonemic, or structural word features. Dependent measures were lateralization, free recall, retrieval organization, and selective attention. The efficiency of allocating attentional resources was inferred from correlations between central and incidental recall. Primary results included the following: Disabled and nondisabled readers' ear asymmetry differences were dependent upon age, orienting instructions, and type of word list; disabled readers' recall and organization scores were lower than skilled readers'; however, both ability groups benefitted from orienting instructions compared to nonorienting instructions; during orienting instructions, disabled readers were less able than skilled readers to divide their attention between target and nontarget word features, especially during interhemispheric processing conditions; and the relative efficiency of allocating attentional resources differed qualitatively between the two ability groups. The results suggest that ability group variations reflect the structure of the memory trace in interaction with ear presentation and encoding processes. It is inferred that disabled readers' inferior memory traces reflect the quantity and internal coherence of information stored in semantic memory as well as the means by which such information is accessed.  相似文献   
958.
959.
960.
We investigated the control judgments of Type A and B actors and observers after five tasks in which actual response-outcome contingency and success were varied systematically. Results indicated that, overall, actors provided higher control judgments than did observers, and both actual contingency and success influenced judged control. Type A and B actors did not differ in their self-perceptions of control but observers judged the Type A actors to have exerted more control than the Type B actors, primarily on positive contingency tasks. These findings suggest that Type As, because of their more active, dynamic style, may be credited by observers with more control or competence than is warranted. By contrast, the more relaxed style of the Type B may lead to lower than warranted evaluations of control or competence. Lastly, Type As were found to learn the contingencies better than Type Bs with important implications for the actual exercise of control.  相似文献   
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