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961.
Aging and temporal discrimination of brief auditory intervals 总被引:1,自引:0,他引:1
Summary In a duration-discrimination experiment, young adults (mean age = 25.1), middle-aged adults (mean age = 45.5), and older adults (mean age = 64.6) were presented with two very brief auditorily marked intervals per trial, and their task was to decide which of the two was longer in duration. An adaptive psychophysical procedure was used to determine difference thresholds in relation to a constant standard interval of 50 ms. It was found that duration-discrimination performance was unaffected by age; all three age groups yielded a difference threshold of approximately 17 ms. It was concluded that the ability to discriminate durations of very brief auditory intervals appears to be based on an underlying timing mechanism that does not slow down with advancing adult age. 相似文献
962.
Social learning theory suggests that parents and peers influence adolescent drinking directly by providing social reinforcement and models for imitation, and indirectly by first influencing various expectations adolescents form about drinking. In this study, longitudinal data were used to investigate several mediators that could account for the relationships between adolescent beer drinking and parent and peer drinking behaviors and attitudes. The results show that peer drinking indirectly influences adolescent drinking by shaping adolescents' norms on drinking, drinking preferences, and expected consequences of drinking related to friends and problem behavior, whereas parental alcohol use and peer attitude toward alcohol largely directly influence adolescent beer drinking. The results suggest that influence is in large part direct or indirect depending on the source of the influence. In addition, different types of mediators may account for different relationships. 相似文献
963.
Perspective-taking is central to much social interaction, but the processes by which it is accomplished are poorly understood. The current study examines accuracy and bias in one type of perspective-taking: inferences about what others know. Twenty-two New York City landmarks were presented in three conditions: Picture Only, Picture-+ Name and Name Only. Subjects estimated the proportion of short- and long-term New York City residents who could identify each landmark from its picture. They also rated their subjective recognition of the stimuli. Subjects in all three conditions were good at estimating stimulus identifiability, but their estimates were biased in the direction of their own knowledge. Estimates of the difference in identifications by short-and long-term residents were relatively inaccurate, probably because the two groups differed less than anticipated. For most but not all subjects, subjective feelings of recognition were significantly correlated with estimates of identifiability. We conclude that perceptions of the distribution of knowledge are socially shared. 相似文献
964.
The sociocultural model of disordered eating proposed by Boskind-White and White (1986) predicts that women with disordered eating will be high in feminine characteristics, while that of Steiner-Adair (1986) predicts they will ascribe to high levels of masculine traits in their ideal woman and perceive a greater discrepancy between their actual and ideal masculine characteristics. To test these predictions 149 women completed questionnaire assessing sex role characteristics and eating attitudes. Positive correlations were found between measures of disordered eating and the extent to which women believed they possessed negative feminine characteristics. There was a greater discrepancy between self and ideal masculine positive scores in subjects with greater eating disturbances. Aspects of sociocultural models of disordered eating receive support from the data. 相似文献
965.
Braithwaite SS 《The Journal of clinical ethics》1991,2(2):97-103
The anticruelty policy is a best-interests test for treatment plans including decisions to forgo life-sustaining therapy for certain incompetent patients. In connection with specific proposed therapy, the policy requires no reference to the patient's unknowable values, subjective experiences, or quality of life. The decision to undertake a treatment plan derives from the caregiver's knowledge of burdens and benefits of that treatment when used in caring for the competent or for those incompetents capable of growth or repair. The caregiver should weigh the potentially cruel effects of treatment against the likelihood of reducing suffering or encumbrance with the treatment. The terms "burden" and "benefit," in fact, are replaced by the terms "cruelty" and "beneficence," as the relevant opposing outcomes that must be weighed. Thus, the anticruelty policy shifts our scrutiny from experiences of the patient that we cannot evaluate to the proposed actions of the competent decision makers and caregivers. Notably, it is a protreatment policy when the goals of medicine are attainable; and it is an anticruelty policy when they are not. The policy does evaluate the world of the patient to the extent that it requires a judgment based upon external appearances about patient pleasure or happiness in living. It presumes to universalize larger societal values about cruelty, beneficence, compassionate concern for the helpless, and certain rights of individuals. And it presumes to universalize on the patient's behalf specific medical values about hopeless injury, timely death, the goals of medicine, and cruelty, which should remain open to societal discussion and revision. The presented definition of hopeless injury does not require brain death, coma, or persistent vegetative state. Specifically, the policy holds that death is timely for a patient with hopeless injury, and that prevention of death for such patients is not a goal of medicine but a cruelty. 相似文献
966.
967.
The present study examines gender differences in children's encoding of gender-connotation from words. The release from proactive interference method was used to measure gender-connotation encoding. Forty-eight third-grade children attending a public elementary school serving a predominantly White middle-socioeconomic-status community participated and were presented with stimulus words in print. The design of the study can be characterized as a two (gender) by two (condition: control vs. experimental) by four (trials) factorial. Results revealed reliable proactive interference buildup and release for gender-connotation for girls, but not for boys. This new finding, taken together with extant research, demonstrates that while both boys and girls have the ability to encode gender-connotation from aurally presented words, the spontaneous activation of gender-connotation attributes with print is not guaranteed for boys. 相似文献
968.
969.
Theoretical Medicine and Bioethics - 相似文献
970.