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991.
A modified form of Nathanson and Becker's (1983) Health Belief Model Questionnaire and other measures designed to assess cognitive processing were administered to low-income black adolescent female clients of an inner-city comprehensive health care clinic. The purpose of the study was to explore determinants of sexual activity and contraceptive use. Subjects were classified as not sexually active (n = 50), sexually active/noncontracepting (n = 20), or sexually active/contracepting (n = 72). Not sexually active subjects tended to be younger, more career motivated, to have a father at home, to be more influenced by family values, and to have more conservative attitudes regarding adolescent sexuality than did sexually active subjects. Sexually active/noncontracepting subjects tended to report fewer benefits and more barriers to the use of contraception. Level of cognitive processing did not differ among the three groups, but was at a lower-than-expected level for age. Finally, inconsistent contraceptive use was common to both sexually active groups. 相似文献
992.
993.
Similarity ratings of pairs of lipread consonants were obtained using a 5-point scale. Matrices were constructed showing mean similarity ratings and confusions among stimuli. Both the similarity and the confusion data provide normative data useful for researchers in many areas. Lipread data collected here are compared with similarity ratings of orthographically and auditorily presented consonants collected by Manning (1977). These comparisons provide information about how stimulus similarity both within and between presentation formats may affect information processing of the three types of stimuli. These data are of special interest to researchers studying the visual processing of speech and the effect of format of presentation on recall. 相似文献
994.
995.
996.
U-shaped learning and frequency effects in a multi-layered perceptron: implications for child language acquisition 总被引:6,自引:0,他引:6
A three-layer back-propagation network is used to implement a pattern association task in which four types of mapping are learned. These mappings, which are considered analogous to those which characterize the relationship between the stem and past tense forms of English verbs, include arbitrary mappings, identity mappings, vowel changes, and additions of a suffix. The degree of correspondence between parallel distributed processing (PDP) models which learn mappings of this sort (e.g., Rumelhart & McClelland, 1986, 1987) and children's acquisition of inflectional morphology has recently been at issue in discussions of the applicability of PDP models to the study of human cognition and language (Pinker & Mehler, 1989; Bever, in press). In this paper, we explore the capacity of a network to learn these types of mappings, focusing on three major issues. First, we compare the performance of a single-layered perceptron similar to the one used by Rumelhart and McClelland with a multi-layered perceptron. The results suggest that it is unlikely that a single-layered perceptron is capable of finding an adequate solution to the problem of mapping stems and past tense forms in input configurations that are sufficiently analogous to English. Second, we explore the input conditions which determine learning in these networks. Several factors that characterize linguistic input are investigated: (a) the nature of the mapping performed by the network (arbitrary, suffixation, identity, and vowel change); (b) the competition effects that arise when the task demands simultaneous learning of distinct mapping types; (c) the role of the type and token frequency of verb stems; and (d) the influence of phonological subregularities in the irregular verbs. Each of these factors is shown to have selective consequences on both successful and erroneous performance in the network. Third, we outline several types of systems which could result in U-shaped acquisition, and discuss the ways in which learning in multi-layered networks can be seen to capture several characteristics of U-shaped learning in children. In general, these models provide information about the role of input in determining the kinds of errors that a network will produce, including the conditions under which rule-like behavior and U-shaped learning will and will not emerge. The results from all simulations are discussed in light of behavioral data on children's acquisition of the past tense and the validity of drawing conclusions about the acquisition of language from models of this sort. 相似文献
997.
S Bossert R G Laessle C Meiller M Junker H Ellgring K M Pirke 《Behaviour research and therapy》1991,29(4):337-341
The effects of 19 meals of different caloric content on slides on palatability and hypothetical duration of consumption were investigated in 7 patients with anorexia nervosa, 17 patients with bulimia nervosa at the beginning and after 8 weeks of hospital treatment. Nine healthy females served as controls. At the beginning of treatment, palatability of low caloric food was significantly higher and hypothetical duration of consumption of high caloric food was significantly longer in patients when compared to controls. After 8 weeks, in the patients palatability of low caloric food had decreased. Dislike for high caloric food remained stable in anorexics. 相似文献
998.
What children can tell us about living in danger 总被引:9,自引:0,他引:9
Developmental challenges faced by children growing up in situations of chronic danger linked to community violence and communal conflict are reviewed. The concept of post-traumatic stress disorder is expanded to include situations of chronic and on-going traumatic stress associated with dangerous environments--war zones and inner city neighborhoods plagued by violence and crime. Of particular importance is the impact of chronic stress and danger on the child's world view, the child's social map, and the child's moral development. On the basis of field work in 5 war zones, the article points to the importance of adult-led "processing" of the young child's experience to his or her psychological coping and moral development. Some of the contradictions operating in such environments are explored--for example, that "fanatical" ideology may provide short-term support for adults and children but also may serve to prolong communal conflict, impede the necessary processing of experience, and increase vulnerability in the long run. 相似文献
999.
Correlates of work-home role conflict for dual-earner couples were examined. Respondents (N= 208) were an equal number of married, employed men and women with children. Data were collected in the northeastern U.S.A. through a survey which measured work-home role conflict, family climate, domestic responsibilities, and activities performed during one's free time. LISREL was used to determine if domestic responsibilities mediate the correlation between gender and work-home conflict. A regression analysis was used to determine the relative effects of domestic responsibilities and family climate on work-home conflict. Results indicate that (a) work-home role conflict is negatively related to family climate for men as well as for women, (b) gender differences in role conflict are partially attributable to gender differences in domestic responsibilities, and (c) domestic responsibilities and family climate each correlate significantly with work-home role conflict. Findings suggest that how one works hard (the conditions under which one lives) may be just as important as how hard one works (the number of tasks one performs). 相似文献
1000.
Multiple role juggling and daily mood states in working mothers: an experience sampling study 总被引:2,自引:0,他引:2
K J Williams J Suls G M Alliger S M Learner C K Wan 《The Journal of applied psychology》1991,76(5):664-674
The effects of multiple role juggling (i.e., simultaneously attending to demands of different roles) on daily mood states of employed mothers were examined. Ss completed activity and mood questionnaires 8 times a day for 8 days. Multiple role juggling had immediate negative effects on task enjoyment and mood. However, contrast effects and habituation to role juggling occurred when mood and satisfaction were examined over time. Furthermore, mood states tended to spill over from one episode to the next within a day, but contrast effects were found across days. These results reflect the complex nature of psychological adjustment to multiple role occupancy. 相似文献