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61.
Past studies have not assessed the prevalence of emotional disturbances in Holocaust survivors seeking medical treatment in a family practice environment. The present study examined the prevalence of lifetime (the presence of symptomatology at any time) and current posttraumatic stress disorder (PTSD) symptoms, general anxiety, and depression in Holocaust survivors seeking medical treatment in a primary care setting. 20 of the 27 Holocaust survivors in our sample received a current diagnosis of PTSD and reported significant symptoms of depression and general anxiety. Although 74% of the survivors were currently diagnosed with PTSD, participants in this study had reported an overall decline in reexperiencing, hyperarousal, and overall PTSD symptoms but exhibited increased avoidance and numbing symptoms throughout the lifespan. These preliminary results suggest that removing avoidance as a defense mechanism during the course of psychotherapy may leave these survivors without an adequate way for coping with their trauma, subsequently increasing their vulnerability to psychopathology. Implications for psychological interventions are provided.  相似文献   
62.
Developmental-behavioral initiation of evolutionary change   总被引:4,自引:0,他引:4  
The traditional approach to evolutionary psychology relies entirely on natural selection as the cause of the evolution of adaptations. Exclusive reliance on natural selection overlooks the fact that changes in development are a necessary prerequisite for evolutionary change. These developmental changes provide the material for natural selection to work on. In the neo-Darwinian scenario, the mechanisms of evolution are mutation or genetic recombination, selection, migration, and eventual reproductive isolation. In the spirit of evolutionary pluralism, the author describes a different 3-stage scenario in which migration (the invasion of new niches or habitats) may occur without mutation or genetic recombination and selection first initiating a change in genes or gene frequencies.  相似文献   
63.
64.
Nonspatial attentional shifts between audition and vision   总被引:2,自引:0,他引:2  
This study investigated nonspatial shifts of attention between visual and auditory modalities. The authors provide evidence that the modality of a stimulus (S1) affected the processing of a subsequent stimulus (S2) depending on whether they shared the same modality. For both vision and audition, the onset of S1 summoned attention exogenously to its modality, causing a delay in processing S2 in a different modality. That undermines the notion that auditory stimuli have a stronger and more automatic alerting effect than visual stimuli (M. I. Posner, M. J. Nissen, & R. M. Klein, 1976). The results are consistent with other recent studies showing cross-modal attentional limitation. The authors suggest that such cross-modal limitation can be produced by simply presenting S1 and S2 in different modalities and that central processing mechanisms are also, at least partially, modality dependent.  相似文献   
65.
Two forms of thinking about the future are distinguished: expectations versus fantasies. Positive expectations (judging a desired future as likely) predicted high effort and successful performance, but the reverse was true for positive fantasies (experiencing one's thoughts and mental images about a desired future positively). Participants were graduates looking for a job (Study 1), students with a crush on a peer of the opposite sex (Study 2), undergraduates anticipating an exam (Study 3), and patients undergoing hip-replacement surgery (Study 4). Effort and performance were measured weeks or months (up to 2 years) after expectations and fantasies had been assessed. Implications for the self-regulation of effort and performance are discussed.  相似文献   
66.
The authors investigated (a). whether the specificity of practice hypothesis is mediated by the importance of visual afferent information for the control of manual aiming movements and (b). how movement planning and online correction processes to the movement initial impulse are affected by the withdrawal of visual information in transfer. In acquisition, participants (N = 40) aimed at targets of different sizes in a full-vision or in a target-only condition before being transferred to a target-only condition without knowledge of results. The results supported the hypothesis that learning is specific to the source or sources of afferent information that are more likely to ensure optimal performance. The results also suggested that individuals will not always use visual afferent information more extensively when aiming at a small rather than at a large target. Instead, in a temporally constrained task, the relative efficiency of visually based corrections appears to mediate how exclusively an individual will rely on online visual afferent information for movement control. Finally, the detailed kinematic analysis performed in the present study clearly indicated that online modifications to the movement primary impulse are possible, arguing for a continuous or pseudo-continuous control of relatively slow aiming movements on the basis of visual afferent input.  相似文献   
67.
We analyzed detection asymmetry, using openand closed squares as target and contextelements. It was found that varying density, regularity, and target eccentricity not only can modulate the amount of asymmetry, but also can produce a reversal in the direction of the asymmetry. The results suggest that the different stimuli are processed with different grains of analysis,consisting of in some cases, single elements and their properties and, in other cases, larger units of the stimulus array and more globalproperties. A detection task that can utilize the properties that are available with a given grain of analysis would show an advantage over a task for which the given grain of analysis is not as favorable, resulting indetection asymmetry in one direction or another.  相似文献   
68.
This study tested and refined a framework that proposes a mechanism for retrieving alternative causes and disabling conditions (Cummins, 1995) during reasoning. Experiment 1 examined the relation between different factors affecting retrieval. The test revealed high correlations between the number of possible alternative causes or disabling conditions and their strength of association and plausibility. Experiment 2 explored the hypothesis that due to a more extended search process, conditional inferences would last longer when many alternative causes or disabling conditions were available. Affirmation of the consequent (AC) and modus ponens (MP) latencies showed the hypothesized pattern. Denial of the antecedent (DA) and modus tollens (MT) inferences did not show latency effects. The experiment also identified an effect of the number of disabling conditions on AC and DA acceptance. Experiment 3 measured efficiency of disabler retrieval by a limited time, disabler generation task. As predicted, better disabler retrieval was related to lower acceptance of the MP and MT inferences.  相似文献   
69.
In a recent issue of this journal, Francis Beckwith's "The Ethics of Referral Kickbacks and Self-Referral and the HMO Physician as Gatekeeper: An Ethical Analysis" provided an admirably provocative defense of the claim that Health Maintenance Organization (HMO) physician gatekeepers are morally indistinguishable from physician referral kickbacks and self-referrals. Here I will argue that Beckwith's defense is weak. I will also make some tentative suggestions about approaching the issue of physician conflicts of interest.  相似文献   
70.
This research addresses the issues of frequency and regularity in auditory verb recognition and their importance for the organization of the mental lexicon in DLI francophones. A primed auditory lexical decision task probes reaction times and response accuracy in DLI and control participants on frequent and infrequent, and regular and irregular, inflected forms of verbs. Results show no priming for inflectionally related forms as well as strong frequency effects in DLI participants. These findings lend additional support to the hypothesis that developmental language impairment is a deficit in lexical representation.  相似文献   
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