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951.
Providing care for a frail older adult has been described as a stressful experience that may erode psychological well-being and physical health of caregivers. In this meta-analysis, the authors integrated findings from 84 articles on differences between caregivers and noncaregivers in perceived stress, depression, general subjective well-being, physical health, and self-efficacy. The largest differences were found with regard to depression (g = .58), stress (g = .55), self-efficacy (g = .54), and general subjective well-being (g = -.40). Differences in the levels of physical health in favor of noncaregivers were statistically significant, but small (g = .18). However, larger differences were found between dementia caregivers and noncaregivers than between heterogeneous samples of caregivers and noncaregivers. Differences were also influenced by the quality of the study, relationship of caregiver to the care recipient, gender, and mean age of caregivers.  相似文献   
952.
953.
Emotional facilitation of sensory processing in the visual cortex   总被引:23,自引:0,他引:23  
A key function of emotion is the preparation for action. However, organization of successful behavioral strategies depends on efficient stimulus encoding. The present study tested the hypothesis that perceptual encoding in the visual cortex is modulated by the emotional significance of visual stimuli. Event-related brain potentials were measured while subjects viewed pleasant, neutral, and unpleasant pictures. Early selective encoding of pleasant and unpleasant images was associated with a posterior negativity, indicating primary sources of activation in the visual cortex. The study also replicated previous findings in that affective cues also elicited enlarged late positive potentials, indexing increased stimulus relevance at higher-order stages of stimulus processing. These results support the hypothesis that sensory encoding of affective stimuli is facilitated implicitly by natural selective attention. Thus, the affect system not only modulates motor output (i.e., favoring approach or avoidance dispositions), but already operates at an early level of sensory encoding.  相似文献   
954.
955.
This study investigated the effects of an internet-based self-help stress management program with a randomized controlled design. Of 85 participants, 26% dropped out, leaving a final sample of 63 participants with 23 in the treatment group and 40 in the waiting list control group. Treatment included applied relaxation, problem solving, time management and cognitive restructuring. All information and treatment interventions were provided via the internet. Results were evaluated with the Perceived Stress Scale and the Hospital Anxiety and Depression Scale. Improvements were seen in both groups, with greater improvements in the self-help treatment group. It is concluded that the internet can be used to provide stress management techniques and result in stress relief. However, spontaneous improvement, differential dropout rate and compliance need to be monitored in future studies.  相似文献   
956.
Employing one correlational and two experimental studies, this paper examines the influence of attachment styles (secure, anxious, avoidant) on a person's experience of equity in intimate relationships. While one experimental study employed a priming technique to stimulate the different attachment styles, the other involved vignettes describing fictitious characters with typical attachment styles. As the specific hypotheses about the single equity components have been developed on the basis of the attachment theory, the equity ratio itself and the four equity components (own outcome, own input, partner's outcome, partner's input) are analyzed as dependent variables. While partners with a secure attachment style tend to describe their relationship as equitable (i.e., they give and take extensively), partners who feel anxious about their relationship generally see themselves as being in an inequitable, disadvantaged position (i.e., they receive little from their partner). The hypothesis that avoidant partners would feel advantaged as they were less committed was only supported by the correlational study. Against expectations, the results of both experiments indicate that avoidant partners generally see themselves (or see avoidant vignettes) as being treated equitably, but that there is less emotional exchange than is the case with secure partners. Avoidant partners give and take less than secure ones.  相似文献   
957.
This study investigated whether retrieval of a noun's grammatical gender benefits from having retrieved that information recently. In response to picture stimuli, participants produced gender-marked pronouns under various priming conditions. The primes differed in that they either necessitated retrieval of grammatical gender (indefinite noun phrase/pronoun) or did not (noun); when they required gender retrieval, they varied in whether they involved access to the same morpheme (pronoun) or a different morpheme (indefinite noun phrase). Relative to an unprimed condition, faster responses were obtained in each condition. Pronoun primes facilitated pronoun naming more than the other prime types, but no difference was observed between noun primes and indefinite noun phrase primes. Thus, although the experiment was sensitive to priming processes, there was no evidence for morpheme-independent gender priming.  相似文献   
958.
We prove some results about the limitations of the expressive power of quantifiers on finite structures. We define the concept of a bounded quantifier and prove that every relativizing quantifier which is bounded is already first-order definable (Theorem 3.8). We weaken the concept of congruence closed (see [6]) to weakly congruence closed by restricting to congruence relations where all classes have the same size. Adapting the concept of a thin quantifier (Caicedo [1]) to the framework of finite structures, we define the concept of a meager quantifier. We show that no proper extension of first-order logic by means of meager quantifiers is weakly congruence closed (Theorem 4.9). We prove the failure of the full congruence closure property for logics which extend first-order logic by means of meager quantifiers, arbitrary monadic quantifiers, and the Härtig quantifier (Theorem 6.1).  相似文献   
959.
960.
Between Physics of Organism and Organismic Physics: Object and Method of Biology. In the history of biological theory one can observe an oscillation between two tendencies of thinking, namely the biologistic and the physicalistic point of view. Both aim at a general or unified theory of nature that is relevant for scientific research as well as for philosophical reflection. In terms of a pluralistic approach these two ways of theory-formation must be rejected. Biology e.g. as a specific natural science, characterized by its mid-position between ‘nomothetic’ and ‘idiographic’ thinking (Windelband), is much more than a subordinate branch of physical knowledge. This very autonomy of biology does not only result from a special methodology or from a specific theoretical framework. On the contrary, the methodological and functional autonomy of biology is due to the very features of the phenomena investigated. These features include multitude, individuality and wholeness. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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