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11.
Three commentaries are offered on the following case: George, age 57, is a previously healthy man who recently underwent surgery for removal of a low-grade malignant thymoma. At the time of admission to the hospital, George stressed to the staff that he had long ago signed a "living will," which he renewed immediately after he learned of his cancer diagnosis. At the time of surgery, the tumor was found to extend into his mediastinum; although it was removable, this required revision of part of the sternum and grafting of the vessels feeding the heart chambers. Because of the resultant tissue damage and neuronal hyperactivity, George experienced postoperative episodes of cardiac arrhythmia and bronchospasm. Unanimous medical opinion was that this situation was a temporary problem that would resolve itself as the tissues healed. Until that time, however, it will be difficult to wean him from ventilatory support. When his stay in the intensive care unit became prolonged, George and his family began to insist that his status be changed to "do not resuscitate" and reminded the staff about his longstanding living will. All of this is happening despite the fact that the patient and family seemingly comprehend that although the short-term interventions are invasive, there is a high probability of a successful outcome. George's cancer prognosis is excellent, and, although he may well have an episode of life-threatening arrhythmia, he is likely to respond to resuscitation interventions. Once the immediate postoperative period is over, his potential for a long and productive life with full capacities is excellent. Consider the following questions: (a) Should George's expressed wishes be respected, or should the staff take additional steps to help him survive the postoperative period, even if that means violating his stated wishes? and (b) What steps might the staff follow in sorting through this problem?  相似文献   
12.
A stimulus leads to a cortical response (i.e., evoked potential [EP]) which may be recorded from electrodes attached to the scalp. However, background cortical activity, considered as noise (n), is typically of equal or greater magnitude than the response, which is considered as signal (s). This situation leads to the masking of the presence of the electrocortical signal. Two methods are described which enable the enhancement of the signal with respect to the noise. The first method outlined is time-domain averaging. Its relation to Fourier averaging is also presented. Time averaging can lead to an enhancement of the signal with respect to the noise, known as the signal-to-noise ratio (SNR), by a factor of root N; N being the number of trials recorded. However, latency variability (i.e., jitter) present in the signal leads to a decrement in this maximal potential enhancement. The second technique is an adaptive filter method of averaged cross-correlations, developed by Woody (1967), which deals with the variable latency problem. The development of a latency corrected average developed by McGillem and Aunon (1977) is also presented. The final section describes methods for data handling once the electrocortical signal has been enhanced. It is then necessary to describe the EP quantitatively. Principal Components Analysis (PCA) allows for the quantitative compact representation of the evoked potential waveform. The method also allows for the testing of the effects of explanatory variables on the EP.  相似文献   
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Seventy-five patients admitted to the psychiatric unit of a general hospital were administered a brief neuropsychological screening battery. Discharge diagnoses obtained from the medical records revealed that 20% had brainbased pathology. A discriminant function analysis resulted in a five-variable model (Symbol-Digit Modalities Test, educational level, Psychiatric-Organic subscale of the MMPI, and Shipley Vocabulary and Abstraction scores) which correctly classified 84% of the subjects, with 87% correct identification of the brain-damaged group. A jackknife cross-validation procedure resulted in comparable hit rates.  相似文献   
15.
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   
16.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.  相似文献   
17.
Comparing visual field asymmetries for bilaterally presented words and corresponding line drawings, we found an RVF advantage for words and no visual field asymmetry for line drawings. We suggested that the RVF advantage previously obtained by Young, Bion, and Ellis (Brain and Language, 11, 54–65, 1980) for bilaterally presented line drawings may have resulted from a forced order of report procedure, noting that the RVF advantage was greater on trials on which subjects were forced to report in the nonpreferred right-to-left order. Young and Ellis (Brain and Language, 20, 166–171, 1983) attempt to discredit this claim and maintain their hypothesis that the RVF advantage for line drawings is attributable to better temporary storage of these stimuli by the left than the right hemisphere. In the present article, we present in greater detail our arguments for the effects of forced order of report on the perception of bilaterally presented stimuli and refute Young and Ellis's ibid. criticisms of this proposal.  相似文献   
18.
Children in grades 2–10 (200 of each sex) assigned desirable and undesirable traits to girls or boys. Half the subjects had an additional option of both sexes. Children in all grades assigned more desirable traits to their own sex and more undesirable traits to the opposite sex, in line with Smith (1939). Both sexes became less positive toward their own sex and more positive toward the opposite sex with increasing age. This pattern also had characterized girls in Smith's study, whereas, boys had shown the opposite pattern. Beginning in the sixth grade, girls were more apt than boys to assign desirable traits to their own sex. Availability of the “both sexes” option decreased stereotyping, especially in girls.  相似文献   
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Sutherland and Young (Br. J. Psychol., 113, 2022, 1056) provide a comprehensive and timely overview of recent developments in research on social judgements of faces, emphasizing the utility of data-driven approaches. Here, we expand on this theme, focusing on how data-driven approaches can provide new insights into the physical characteristics in face images that best predict social judgements.  相似文献   
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