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161.
In the clinical literature, thought suppression is considered to play a role in the development of intrusion-related psychiatric syndromes, such as obsessive-compulsive disorder, acute or posttraumatic stress disorder, phobias, and addiction. This assumption goes back to a study by D. M. Wegner, D. J. Schneider, S. R. Carter, and T. L. White (1987) in which participants were asked to suppress thoughts of a white bear, an assignment that proved to be nearly impossible to complete. The present two studies sought to explore the influence of the content of control instructions on intrusion frequency in thought suppression experiments. Notably, during nonsuppression (i.e., control) periods, participants can either be instructed to think about white bears (i.e., expression instruction), or to think of anything including white bears (i.e., liberal instruction). Results indicated that expression instructions resulted in an increased number of target thoughts, while liberal instructions did not. Implications for the interpretation of thought suppression findings are discussed.  相似文献   
162.
Empirical examinations of the hypothesis of dedifferentiation of cognitive abilities in old and very old age (a) do not account for possible retest effects, which consequently may yield biased estimates of age effects, and (b) focus on time-independent relations (e.g., number of latent constructs, correlations between latent or measured variables). The authors applied a structural equation model with statistical control for retest effects to investigate the dynamic relations between a marker of perceptual speed (cross out) and a marker of verbal fluency (category-fruits). Longitudinal data are from 5 waves of the Swiss Interdisciplinary Longitudinal Study on the Oldest Old (N = 377, baseline age range = 79.5- 84.5 years). The authors found that, independently of retest effects, performance on the cross-out task affected changes in performance on the category task while the opposite did not hold true. This analytical technique could be applied to various markers of broad fluid-mechanic and broad crystallized-pragmatic components of cognition.  相似文献   
163.
These recommendations describe the minimum standard criteria for genetic counseling and testing of individuals and families with fragile X syndrome, as well as carriers and potential carriers of a fragile X mutation. The original guidelines (published in 2000) have been revised, replacing a stratified pre- and full mutation model of fragile X syndrome with one based on a continuum of gene effects across the full spectrum of FMR1 CGG trinucleotide repeat expansion. This document reviews the molecular genetics of fragile X syndrome, clinical phenotype (including the spectrum of premature ovarian failure and fragile X-associated tremor-ataxia syndrome), indications for genetic testing and interpretation of results, risks of transmission, family planning options, psychosocial issues, and references for professional and patient resources. These recommendations are the opinions of a multicenter working group of genetic counselors with expertise in fragile X syndrome genetic counseling, and they are based on clinical experience, review of pertinent English language articles, and reports of expert committees. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. The professional judgment of a health care provider, familiar with the facts and circumstances of a specific case, will always supersede these recommendations.  相似文献   
164.
Many studies of task switching have found that a prolonged preparation time reduces switch costs. An alternative manipulation of task preparation is based on sequential task predictability, rather than preparation time. In Experiments 1 and 2 of the present study, participants performed explicitly instructed task sequences (i.e., AABB) and were then transferred to a random sequence. The observed benefit of predictability-based task preparation was not switch specific. In Experiment 3, the participants changed from random to predictable tasks. The observed predictability benefit again was not switch specific. The data thus suggest that task switching does not necessarily require a switch-specific reconfiguration process. Rather, task-specific control processes may be needed in both task switches and repetitions.  相似文献   
165.
Twenty-four detoxified opiate addicts were randomized to an experimental group and a control group to evaluate efficacy of a group cue-exposure treatment to reduce or extinguish classically conditioned responses to drug-related stimuli. Assessment included psychophysiological responses (skin temperature, skin conductance level--SCL--, and heart rate) to a videotape and subjective measures (subjective craving, positive and negative affect) before and after the videotape. The experimental group received a group cue-exposure program to drug-related stimuli that comprised twelve treatment sessions administered three times weekly. The treatment program significantly reduced conditioned responses to drug-related stimuli, as measured by SCL and positive affect.  相似文献   
166.
Over the last years several European patents were opposed for protecting technology violating the morality requirement under Article 53(a) EPC. Attempts have been made by the Appeal Boards of the European Patent Office (EPO), as well as by amendments introduced into the Implementing Regulations of the European Patent Convention (EPC), to address this sensitive patentability requirement more precisely. The most recent hot topic coming up in this context is the patentability of stem cells. It is to be expected that this discussion will still go on in the field of biotechnological inventions for the next several years. An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights and Patents,” held in Warsaw, Poland on 23–24 April, 2004.  相似文献   
167.
Nanotechnology — A new field of ethical inquiry?   总被引:2,自引:0,他引:2  
Parallel to the public discussion on the benefits and risks of nanotechnology, a debate on the ethics of nanotechnology has begun. It has been postulated that a new “nano-ethics” is necessary. In this debate, the — positive as well as negative — visionary and speculative innovations which are brought into connection with nanotechnology stand in the foreground. In this contribution, an attempt is made to discover new ethical aspects of nanotechnology in a more systematic manner than has been the case. It turns out that there are hardly any completely new ethical aspects raised by nanotechnology. It is much rather primarily a case of gradual shifts of emphasis and of relevance in questions which, in principle, are already known and which give reason for ethical discussions on nanotechnology. In a certain manner, structurally novel ethical aspects arise through the important role played by visions in the public discourse. New questions are also posed by the fact that previously separate lines of ethical reflection converge in the field of nanotechnology. The proposal of an independent “nano-ethics”, however, seems exaggerated.  相似文献   
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