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771.
We examined actual and perceived trajectories of change in life satisfaction in a national sample of 3,793 adults, ages 24 to 74 at baseline, who provided retrospective, present, and prospective ratings on two occasions 8 to 10 years apart. There was little actual change in satisfaction ratings, but there were age differences in anticipated change, with young adults expecting things to improve and older adults expecting decline. When we compared the actual (present) ratings with corresponding past or future ratings, older adults showed more temporal realism (retrospective and anticipatory ratings matched actual levels) than did young and middle-aged adults; in other words, young and middle-aged adults showed greater illusion (retrospective and prospective ratings overestimated or underestimated actual levels). At all ages, however, temporal realism was associated with more adaptive current functioning than was illusion. We discuss these findings from a life-span developmental perspective on motivational shifts from growth to maintenance and consider the implications of accuracy in evaluating the past and future.  相似文献   
772.
Common Representations of Abstract Quantities   总被引:2,自引:0,他引:2  
ABSTRACT— Representations of abstract quantities such as time and number are essential for survival. A number of studies have revealed that both humans and nonhuman animals are able to nonverbally estimate time and number; striking similarities in the behavioral data suggest a common magnitude-representation system shared across species. It is unclear, however, whether these representations provide animals with a true concept of time and number, as posited by Gallistel and Gelman (2000) . In this article, we review the prominent cognitive and neurobiological models of timing and counting and explore the current evidence suggesting that nonhuman animals represent these quantities in a modality-independent (i.e., abstract) and ordered manner. Avenues for future research in the area of temporal and mathematical cognition are also discussed.  相似文献   
773.
Personality in domestic cats   总被引:1,自引:0,他引:1  
Personality ratings of 196 cats were made by their owners using a 5-point Likert scale anchored by 1: not at all and 5: a great deal with 12 items: timid, friendly, curious, sociable, obedient, clever, protective, active, independent, aggressive, bad-tempered, and emotional. A principal components analysis with varimax rotation identified three intepretable components. Component I had high loadings by active, clever, curious, and sociable. Component II had high loadings by emotional, friendly, and protective, Component III by aggressive and bad-tempered, and Component IV by timid. Sex was not associated with any component, but age showed a weak negative correlation with Component I. Older animals were rated less social and curious than younger animals.  相似文献   
774.
Although there is a large and growing literature on tailored print health behavior change interventions, it is currently not known if or to what extent tailoring works. The current study provides a meta-analytic review of this literature, with a primary focus on the effects of tailoring. A comprehensive search strategy yielded 57 studies that met inclusion criteria. Those studies-which contained a cumulative N = 58,454-were subsequently meta-analyzed. The sample size-weighted mean effect size of the effects of tailoring on health behavior change was found to be r = .074. Variables that were found to significantly moderate the effect included (a) type of comparison condition, (b) health behavior, (c) type of participant population (both type of recruitment and country of sample), (d) type of print material, (e) number of intervention contacts, (f) length of follow-up, (g) number and type of theoretical concepts tailored on, and (h) whether demographics and/or behavior were tailored on. Implications of these results are discussed and future directions for research on tailored health messages and interventions are offered.  相似文献   
775.
Animal analogue studies show that damaged adult brains reorganize to accommodate compromised functions. In the human arena, functional magnetic resonance imaging (fMRI) and other functional neuroimaging techniques have been used to study reorganization of language substrates in aphasia. The resulting controversy regarding whether the right or the left hemisphere supports language recovery and treatment progress must be reframed. A more appropriate question is when left-hemisphere mechanisms and when right-hemisphere mechanisms support recovery of language functions. Small lesions generally lead to good recoveries supported by left-hemisphere mechanisms. However, when too much language eloquent cortex is damaged, right-hemisphere structures may provide the better substrate for recovery of language. Some studies suggest that recovery is particularly supported by homologues of damaged left-hemisphere structures. Evidence also suggests that under some circumstances, activity in both the left and right hemispheres can interfere with recovery of function. Further research will be needed to address these issues. However, daunting methodological problems must be managed to maximize the yield of future fMRI research in aphasia, especially in the area of language production. In this review, we cover six challenges for imaging language functions in aphasia with fMRI, with an emphasis on language production: (1) selection of a baseline task, (2) structure of language production trials, (3) mitigation of motion-related artifacts, (4) the use of stimulus onset versus response onset in fMRI analyses, (5) use of trials with correct responses and errors in analyses, and (6) reliability and stability of fMRI images across sessions. However, this list of methodological challenges is not exhaustive. Once methodology is advanced, knowledge from conceptually driven fMRI studies can be used to develop theoretically driven, mechanism-based treatments that will result in more effective therapy and to identify the best patient candidates for specific treatments. While the promise of fMRI in the study of aphasia is great, there is much work to be done before this technique will be a useful clinical tool.  相似文献   
776.
The aim of this study was to investigate the reliability and validity of the Fatigue Impact Scale (FIS) among patients with chronic obstructive pulmonary disease (COPD) and shorten the questionnaire. The empirically developed FIS, which comprised three subscales (cognitive, physical and psychosocial), was tested originally on Pipers' theoretical framework of subjective manifestations of fatigue, including behavioural, physical, emotional and cognitive expressions. The data analysed here consisted of responses from 296 patients with COPD who reported fatigue. The dimensionality of the FIS was examined using confirmatory factor analysis. A reduction of 15 items from the original FIS was made based on theory, modification indices and factor loadings. The results indicate that a nested-factor model with one general behavioural factor and three specific factors, physical, emotional and cognitive, shows acceptable fit. A modified version of 25 items, FIS-25 was developed. The original FIS and the FIS-25 were able to discriminate between patients with differing duration of fatigue. Test - retest correlations ranged from .70 to .85 for items and .94 for the total scale. Due to modification, the FIS-25 needs to be validated on a new group of patients with COPD.  相似文献   
777.
In the present exploratory study based on 7 subjects, we examined the composition of magnetoencephalographic (MEG) brain oscillations induced by the presentation of an auditory, visual, and audio-visual stimulus (a talking face) using an oddball paradigm. The composition of brain oscillations were assessed here by analyzing the probability-classification of short-term MEG spectral patterns. The probability index for particular brain oscillations being elicited was dependent on the type and the modality of the sensory percept. The maintenance of the integrated audio-visual percept was accompanied by the unique composition of distributed brain oscillations typical of auditory and visual modality, and the contribution of brain oscillations characteristic for visual modality was dominant. Oscillations around 20 Hz were characteristic for the maintenance of integrated audio-visual percept. Identifying the actual composition of brain oscillations allowed us (1) to distinguish two subjectively/consciously identical mental percepts, and (2) to characterize the types of brain functions involved in the maintenance of the multi-sensory percept.  相似文献   
778.
Prospective links among reactive aggression, proactive aggression, and victimization by peers were investigated in a longitudinal sample of 238 preadolescents (aged 10-13 years, 52% girls). No predictive links were found between victimization and either type of aggression among girls. Among boys, reactive aggression predicted higher future levels of victimization but was not itself affected by prior victimization. In contrast, boys' proactive aggression predicted lower levels of future victimization and was itself reduced by their prior victimization. Finally, reactive aggression predicted later proactive aggression for both boys and girls. These results are explained in terms of the different reactions that others have to proactive and reactive aggression, the different functions they serve, and to the different types of aggression that are common for boys and girls.  相似文献   
779.
The current study involved a comprehensive comparative examination of overt and relational aggression and victimization across multiple perspectives in the school setting (peers, teachers, observers in the lunchroom, self-report). Patterns of results involving sociometic status, ethnicity and gender were explored among 4th graders, with particular emphasis on girls. Controversial and rejected children were perceived as higher on both forms of aggression than other status groups, but only rejected children were reported as victims. Both European American and African American girls showed a greater tendency toward relational aggression and victimization than overt aggression or victimization. Results indicated negative outcomes associated with both relational and overt victimization and especially overt aggression for the target girl sample. Poorer adjustment and a socially unskillful behavioral profile were found to be associated with these three behaviors. However, relational aggression did not evidence a similar negative relation to adjustment nor was it related to many of the behaviors examined in the current study. Implications of these results are discussed.  相似文献   
780.
The purpose of this research was to understand institutional review board (IRB) challenges regarding youth-focused research submissions and to present advice from administrators. Semistructured self-report questionnaires were sent via e-mail to administrators identified using published lists of universities and hospitals an Internet searches. Of 183 eligible institutions, 49 responded. One half indicated they never granted parental waivers. Among those considering waivers, decision factors included research risks, survey content, and feasibility. Smoking and substance abuse research among children was generally considered more than minimal risk. These findings are consistent with those from a study conducted by Mammel and Kaplan (1995), which investigated IRB practices concerning protocols involving adolescent participants. IRBs and investigators need to become aware of regulations' flexibility to ensure adequate participant protection. Investigators need to limit jargon and assumptions about participants' understanding of research objectives.  相似文献   
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