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171.
Immortality     
In December, the President's Council on Bioethics released Beyond Therapy: Biotechnology and the Pursuit of Happiness. Here, Lustig discusses the six-part report that provides a balanced but critical assessment of actual and prospective developments in biotechnology and seeks to anchor its discussion in shared moral and metaphysical concerns--the nature of human nature, and the social and political implications of unfettered choices in altering the human prospect through biotechnology.  相似文献   
172.
In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive-compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive-compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders.  相似文献   
173.
The association of college attendance with alcohol use and alcohol use disorders was examined in a population-based young adult female twin sample identified from a systematic search of birth records. College-attending women consumed a larger overall volume of alcohol than did their non-college-attending peers, but they were not more likely to be diagnosed with an alcohol use disorder. Significant associations between college attendance and alcohol involvement were probed using 3 different complementary research designs: multivariate cross-sectional analyses, longitudinal analyses of the precollege and college years, and cotwin-control analyses of twin pairs discordant for attending college. Although demographic and lifestyle characteristics accounted for most or all of the association between college attendance and alcohol involvement, there was 1 aspect of drinking behavior, occasionally consuming large quantities of alcohol, that remained significantly associated with college attendance even after controlling for these characteristics or for genetic and family background factors. These results are consistent with the conclusion that some aspect of the college experience may be an important environmental risk factor for this pattern of drinking among young adults.  相似文献   
174.
The authors examined the core characteristics, component processes, antecedents, and function of state inspiration. In Studies 1 and 2, inspiration was contrasted with baseline experience and activated positive affect (PA) using a vivid recall methodology. Results supported the tripartite conceptualization of inspiration. Confirmatory factor analysis indicated that inspiration may be decomposed into separate processes related to being inspired "by" and being inspired "to." Study 3 found that daily inspiration is triggered by illumination among individuals high in receptive engagement, whereas activated PA is triggered by reward salience among individuals high in approach temperament. Approach temperament was also implicated in being inspired "to." Inspiration and activated PA appear to serve different functions: transmission and acquisition, respectively.  相似文献   
175.
Catatonia, long viewed as a motor disorder, may be better understood as a fear response, akin to the animal defense strategy tonic immobility (after G. G. Gallup & J. D. Maser, 1977). This proposal, consistent with K. L. Kahlbaum's (1874/1973) original conception, is based on similarities between catatonia and tonic immobility ("death feint") as well as evidence that catatonia is associated with anxiety and agitated depression and responds dramatically to benzodiazepines. It is argued that catatonia originally derived from ancestral encounters with carnivores whose predatory instincts were triggered by movement but is now inappropriately expressed in very different modern threat situations. Found in a wide range of psychiatric and serious medical conditions, catatonia may represent a common "end state" response to feelings of imminent doom and can serve as a template to understand other psychiatric disorders.  相似文献   
176.
A semantic differential scale was administered to 208 school children when they were in the second, fourth, sixth, eighth, tenth, and twelfth grades. Their perceptions towards two concepts were measured, Education (going to school) and Work (having a job). Each semantic differential scale had 15 adjective pairs and reflected the three underlying factors of Evaluative, Potency, and Activity. Because the study was conducted for 10 years (ages seven to 18), the changing cognitive developmental stages of the children were expected to influence factor analytic and reliability results. Confirmatory factor analysis, which forced the data into three factors, did not clearly identify the expected three factors, although more items loaded on the three factors with age. An exploratory factor analysis identified a trend across grades from six to four factors over time. Reliability also improved across age groups. Caution should be exercised when using the semantic differential with young children in investigations of abstract concepts.  相似文献   
177.
Cortical reorganization in poststroke aphasia is not well understood. Few studies have investigated neural mechanisms underlying language recovery in severe aphasia patients, who are typically viewed as having a poor prognosis for language recovery. Although test-retest reliability is routinely demonstrated during collection of language data in single-subject aphasia research, this is rarely examined in fMRI studies investigating the underlying neural mechanisms in aphasia recovery. The purpose of this study was to acquire fMRI test-retest data examining semantic decisions both within and between two aphasia patients. Functional MRI was utilized to image individuals with chronic, moderate-severe nonfluent aphasia during nonverbal, yes/no button-box semantic judgments of iconic sentences presented in the Computer-assisted Visual Communication (C-ViC) program. We investigated the critical issue of intra-subject reliability by exploring similarities and differences in regions of activation during participants' performance of identical tasks twice on the same day. Each participant demonstrated high intra-subject reliability, with response decrements typical of task familiarity. Differences between participants included greater left hemisphere perilesional activation in the individual with better response to C-ViC training. This study provides fMRI reliability in chronic nonfluent aphasia, and adds to evidence supporting differences in individual cortical reorganization in aphasia recovery.  相似文献   
178.
At the centenary of Spearman's seminal 1904 article, his general intelligence hypothesis remains one of the most influential in psychology. Less well known is the article's other hypothesis that there is "a correspondence between what may provisionally be called 'General Discrimination' and 'General Intelligence' which works out with great approximation to one or absoluteness" (Spearman, 1904, p. 284). Studies that do not find high correlations between psychometric intelligence and single sensory discrimination tests do not falsify this hypothesis. This study is the first directly to address Spearman's general intelligence-general sensory discrimination hypothesis. It attempts to replicate his findings with a similar sample of schoolchildren. In a well-fitting structural equation model of the data, general intelligence and general discrimination correlated .92. In a reanalysis of data published byActon and Schroeder (2001), general intelligence and general sensory ability correlated .68 in men and women. One hundred years after its conception, Spearman's other hypothesis achieves some confirmation. The association between general intelligence and general sensory ability remains to be replicated and explained.  相似文献   
179.
Following F. Zaal and R. J. Bootsma (1995), the authors studied whether the decelerative phase of a reaching movement could be modeled as a constant tau-dot strategy resulting in a soft collision with the object. Specifically, they investigated whether that strategy is sustained over different viewing conditions. Participants (N = 11) were required to reach for 15- and 50-mm objects at 2 different distances under 3 conditions in which visual availability of the immediate environment and of the reaching hand were varied. Tau-dot estimates and goodness-of-fit were highly similar across the 3 conditions. Only within-participant variability of tau-dot estimates was increased when environmental cues were removed. That finding suggests that the motor system uses a tau-dot strategy involving the intermodal (i.e., visual, proprioceptive, or both) specification of information to regulate the decelerative phase of reaching under restricted viewing conditions. The authors provide recommendations for improving the derivation of tau;(x) estimates and stress the need for further research on how time-to-contact information is used in the regulation of the dynamics of actions such as reaching.  相似文献   
180.
A very powerful form of preoedipal guilt stems from a sense of having damaged the life-giving parent with one's most basic needs. A related phenomenon is the child's sense that another subjectivity has deliberately chosen to give and sustain the child's life. This experience gives rise to a compelling mixture of awe, reverence, and obligation, a sense of guilt about being born, of debt concerning the gift of life. This sense of guilt and debt are part of every child's development. Depending on how conflicts surrounding them are negotiated, the child can come to feel either an appetite for living or a crushing sense of selfishness and unworthiness. Such forms of guilt and debt may lead not only to masochism generally, but to a particularly pernicious form of negative therapeutic reaction that can sabotage psychoanalytic work. A patient may feel, for instance, that a successful psychoanalysis is a selfish indulgence and an immoral betrayal of a sacred duty to rescue his or her parents from their misery. Guilt about being born and the sense of debt concerning the gift of life are linked to various developmental, psychodynamic, interpersonal, and cultural phenomena.  相似文献   
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