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251.
A 47-year-old right-handed man underwent craniotomy for clipping of an aneurism at the trifurcation of the left middle cerebral artery. Subsequently, he suffered a left hemisphere CVA after which his speech and language resembled that of Broca's aphasia with accompanying apraxia of speech. Medical, behavioral, and acoustical data amassed over a period of several months indicated numerous contraindications to traditional diagnoses of Broca's aphasia, apraxia of speech, and dysarthria. Ultimately, it was determined that the patient had a selective impairement of phonation or laryngeal apraxia. This was illustrated dramatically when he was taught to use an electrolarynx which allowed him to bypass his disrupted phonatory system. Speaking with the electrolarynx, the patient communicated normally. Any semblance of Broca's aphasia disappeared. Supralaryngeal articulation was normal; apraxia of speech behaviors were absent. This case report indicates that dissociation of oral and laryngeal gestures due to brain injury is possible. Mechanisms underlying such a dissociation for this case are reviewed. The possibility of discrete center lesions in the frontal motor association area causing different types of apraxia of speech is discussed.  相似文献   
252.
Robert K. Shope 《Erkenntnis》1988,28(3):321-362
A complex theory concerning powers, natures, and causal necessity has emerged from the writings of P. H. Hare, E. H. Madden, and R. Harré. In the course of rebutting objections that other critics have raised to the power account of causation, I correct three of its genuine difficulties: its attempt to analyze power attributions in terms of conditional statements; its characterization of the relation between something's powers and its nature; and its doctrines concerning conceptual necessity. The resulting interpretation of causal modalities is then subsumed under a more general power account of modality, related at a number of points to considerations concerning powers, and further illustrating their philosophical importance.  相似文献   
253.
254.
Memory and awareness in a patient with multiple personality disorder   总被引:1,自引:0,他引:1  
We studied an individual with multiple personality disorder in whom each of several personalities claimed to have no direct awareness of the others and to be unable to consciously remember the experiences of other personalities. A broad selection of implicit and explicit memory tests was used to determine the extent to which one personality had access to knowledge acquired by another and the circumstances in which that knowledge would be expressed. The implicit assessment of memory was a necessary but not sufficient condition for demonstrating interpersonality access. The degree of compartmentalization of knowledge in this patient depended largely on whether the interpretation of presented information was likely to differ across personalities.  相似文献   
255.
Assessment of methods for measuring social support   总被引:2,自引:0,他引:2  
A rapidly expanding literature documents the effects of social support on physical and psychological well-being. Although definitions vary, most include both tangible components (e.g., financial assistance and physical aid) and intangible components (e.g., encouragement and guidance). Social support has been implicated in the mediation of stressful life events, recovery from illness, and increased program adherence. There are many inconsistent findings in the literature, however, and it is difficult to resolve discrepancies because measures of social support vary widely from study to study. To guide in the selection of measurement methods for research and applied work, 23 techniques for assessing social support are reviewed and evaluated. Criteria for favorable evaluation included reliability coefficients greater than .8 and documentation of validity. Correlations between various social support and criterion measures are simulated in order to demonstrate the consequences of choosing a measure with low reliability. Scale developers reported reliability data for 19 of the reviewed measures. Internal consistency coefficients ranged from .31 to .98. Test-retest coefficients ranged from .22 to .96. At least some validity documentation was available for 13 of the scales. Discriminant validity evidence, however, is almost universally absent. Despite psychometric weaknesses and variability among the scales, researchers have several instruments available to them.  相似文献   
256.
The purpose of this investigation was to evaluate carefully smoking-related knowledge and beliefs and their relationships to smoking status in a large, heterogeneous sample of smokers and nonsmokers in two settings: (a) a large, biracial southern city and (b) a small midwestern community. Participants were 611 (198 male, 413 female) adult respondents to a random-dialing telephone survey in Fargo, North Dakota (n = 200), and Memphis, Tennessee (n = 411). Each participant was given the Smoking Attitudes Survey, which assesses generalized health beliefs as well as health-related problems associated with smoking. Participants' knowledge of smoking-associated diseases (e.g., lung cancer) and of diseases not associated with smoking (e.g., kidney stones) was assessed. Stepwise regression analysis of composite knowledge scores revealed four independent predictors of the health consequences of smoking: education, race, smoking status, and income. Smokers, compared to nonsmokers, reported less knowledge related to the health consequences of smoking, were more likely to be male, were less concerned with the health consequences of smoking, and were more concerned about the health consequences of cholesterol. The best predictor of smokers who had never attempted cessation was their greater concern over weight control when compared to smokers with a history of smoking cessation attempts. The results are discussed in terms of smoking prevention and intervention efforts.  相似文献   
257.
The hypothesis that physical exercise provides benefits to individuals under periods of life stress has rarely been subject to empirical verification. This article presents the results of a longitudinal study of stress and well-being in adolescence in which the ability of exercise to buffer stress-induced deteriorations in physical health was examined. In accordance with predictions, prospective analyses revealed that the negative impact of stressful life events on health declined as exercise levels increased. These findings suggest that exercise may be a valuable resource for combating life stress. Discussion centers on possible mediating mechanisms and on the practical implications of the results.  相似文献   
258.
The cynomolgus macaque provides a suitable primate model for studying how psychosocial factors contribute to coronary artery atherogenesis. Important interactions with diet, sex, and behaviorally elicited cardiovascular reactivity are described.  相似文献   
259.
This study examined the independent and joint effects of cigarette smoking and caffeine consumption on blood pressure (BP) and heart rate (HR) reactions to stress in male and female college students. Following an initial physiological baseline, participants received one of four experimental treatments (paced smoking, caffeine, smoking plus caffeine, or neither) and had BP and HR measured before, during, and after two stressful tasks. The results revealed that, compared with the control condition, caffeine ingestion enhanced the magnitude of stress-induced systolic BP and HR reactions. Smoking combined additively with stress, and the joint effect of smoking and caffeine was no greater than either taken alone. Males and females were generally similar in their BP and HR responses to smoking, caffeine, and stress. Inconsistencies with previous research and possible physiological mechanisms underlying the observed effects are discussed.  相似文献   
260.
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