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81.
Extraversion is a broad, multifaceted trait, yet researchers are still unsure of its defining characteristics. One possibility is that the essential feature of extraversion is the tendency to enjoy social situations. An alternative possibility is that extraversion represents sensitivity to rewards and the tendency to experience pleasant affect. In three studies, participants rated situations that varied on two dimensions: (a) whether they were social or nonsocial and (b) whether they were very pleasant, moderately pleasant, moderately unpleasant, or very unpleasant. Extraverts only rated social situations more positively than introverts did when the situations were pleasant, and extraverts also rated nonsocial situations more positively than introverts did if the situations were pleasant. Thus, the pleasantness of situations was more important than whether they were social or nonsocial in determining extraverts' and introverts' enjoyment.  相似文献   
82.
The need for automating behavioral observations and the evolution of systems developed for that purpose is outlined. Video tracking systems enable researchers to study behavior in a reliable and consistent way and over longer time periods than if they were using manual recording. To overcome limitations of currently available systems, we have designed EthoVision, an integrated system for automatic recording of activity, movement, and interactions of animals. The EthoVision software is presented, highlighting some key features that separate EthoVision from other systems: easy file management, independent variable definition, flexible arena and zone design, several methods of data acquisition allowing identification and tracking of multiple animals in multiple arenas, and tools for visualization of the tracks and calculation of a range of analysis parameters. A review of studies using EthoVision is presented, demonstrating the system’s use in a wide variety of applications. Possible future directions for development are discussed.  相似文献   
83.
Social support is broad term encompassing a variety of constructs, including support perceptions (perceived support) and receipt of supportive behaviors (received support). Of these constructs, only perceived support has been regarded as consistently linked to health, and researchers have offered differing assessments of the strength of the received-perceived support relationship. An overall estimate of the received-perceived support relationship would clearly further the dialogue on the relationship between received and perceived support and thus assist in the theoretical development of the field. This study evaluated all available studies using the Inventory of Socially Supportive Behaviors (ISSB; Barrera, Sandler, & Ramsey, 1981, American Journal of Community Psychology, 9, 435–447) and any measure of perceived social support. Using effect sizes from 23 studies, we found an average correlation of r = .35, p < .001. Implications of this estimate for further development of models of social support as well as interventions to enhance social support are discussed.  相似文献   
84.
ABSTRACT— Hedonic adaptation refers to the process by which individuals return to baseline levels of happiness following a change in life circumstances. Dominant models of subjective well-being (SWB) suggest that people can adapt to almost any life event and that happiness levels fluctuate around a biologically determined set point that rarely changes. Recent evidence from large-scale panel studies challenges aspects of this conclusion. Although inborn factors certainly matter and some adaptation does occur, events such as divorce, death of a spouse, unemployment, and disability are associated with lasting changes in SWB. These recent studies also show that there are considerable individual differences in the extent to which people adapt. Thus, happiness levels do change, and adaptation is not inevitable.  相似文献   
85.
Perception of stress with consequent activation of a neuroendocrine cascade causes changes in immune function that may be bi-directional, with alterations in basal levels of biological parameters outside the optimal range. In this cross-sectional study of 302 healthy persons (males 56.3%, females 43.7%) aged 41-46 years, higher stress levels, as assessed by questionnaire measures of recurrent and recent perceived stress, were associated with a 4-fold greater risk of having a high compared to mid-range serum neopterin concentration, indicating activation of cellular immune mechanisms [adjusted odds ratio, OR; (95% confidence intervals, CI): Low stress=1.00 (reference group); Medium stress=4.13 (1.51, 11.29); High stress=4.63, (1.35, 15.83), p for trend=0.01]. Higher stress levels were associated with a 3-fold greater risk of having signs of humoral immune activation, as indicated by salivary IgA concentration [high compared to mid-range salivary IgA: Low stress=1.00 (reference group); Medium stress=1.06 (0.48, 2.34); High stress=3.62 (1.26, 10.39), p for trend=0.02], but also a 4-fold greater risk of humoral immune depression [low compared to mid-range IgA: Low stress=1.00 (reference group); Medium stress=1.72 (0.74, 3.99); High stress=4.38 (1.47, 13.00), p for trend=0.02]. In conclusion, in this cross-sectional study, higher stress levels were associated with higher serum neopterin and both elevated and depressed salivary IgA levels. These findings emphasise the importance of considering that stress may have bi-directional effects on immune mechanisms, and are consistent with an activational effect of chronic, perceived stress on cellular immunity, and a bi-directional effect on IgA levels, one aspect of humoral immunity.  相似文献   
86.
The Optimum Level of Well-Being: Can People Be Too Happy?   总被引:2,自引:0,他引:2  
ABSTRACT— Psychologists, self-help gurus, and parents all work to make their clients, friends, and children happier. Recent research indicates that happiness is functional and generally leads to success. However, most people are already above neutral in happiness, which raises the question of whether higher levels of happiness facilitate more effective functioning than do lower levels. Our analyses of large survey data and longitudinal data show that people who experience the highest levels of happiness are the most successful in terms of close relationships and volunteer work, but that those who experience slightly lower levels of happiness are the most successful in terms of income, education, and political participation. Once people are moderately happy, the most effective level of happiness appears to depend on the specific outcomes used to define success, as well as the resources that are available.  相似文献   
87.
The idea that strong social relationships can buffer the negative effects of stress on well‐being has received much attention in existing literature. However, previous studies have used less than ideal research designs to test this hypothesis, making it difficult to draw firm conclusions regarding the buffering effects of social support. In this study, we examined the buffering hypothesis in the context of reaction and adaptation to widowhood in three large longitudinal datasets. We tested whether social relationships moderated reaction and adaptation to widowhood in samples of people who experienced loss of a spouse from three longitudinal datasets of nationally representative samples from Germany (N = 1,195), Great Britain (N = 562), and Australia (N = 298). We found no evidence that social relationships established before widowhood buffered either reaction or adaptation to the death of one's spouse. Similarly, social relationships that were in place during the first year of widowhood did not help widows and widowers recover from this difficult event. Social relationships acquired prior to widowhood, or those available in early stages of widowhood, do not appear to explain individual differences in adaptation to loss.  相似文献   
88.
Adding a transparent truth predicate to a language completely governed by classical logic is not possible. The trouble, as is well-known, comes from paradoxes such as the Liar and Curry. Recently, Cobreros, Egré, Ripley and van Rooij have put forward an approach based on a non-transitive notion of consequence which is suitable to deal with semantic paradoxes while having a transparent truth predicate together with classical logic. Nevertheless, there are some interesting issues concerning the set of metainferences validated by this logic. In this paper, we show that this logic, once it is adequately understood, is weaker than classical logic. Moreover, the logic is in a way similar to the paraconsistent logic LP.  相似文献   
89.
90.
Children show a remarkable degree of consistency in learning some words earlier than others. What patterns of word usage predict variations among words in age of acquisition? We use distributional analysis of a naturalistic corpus of child-directed speech to create quantitative features representing natural variability in word contexts. We evaluate two sets of features: One set is generated from the distribution of words into frames defined by the two adjacent words. These features primarily encode syntactic aspects of word usage. The other set is generated from non-adjacent co-occurrences between words. These features encode complementary thematic aspects of word usage. Regression models using these distributional features to predict age of acquisition of 656 early-acquired English words indicate that both types of features improve predictions over simpler models based on frequency and appearance in salient or simple utterance contexts. Syntactic features were stronger predictors of children's production than comprehension, whereas thematic features were stronger predictors of comprehension. Overall, earlier acquisition was predicted by features representing frames that select for nouns and verbs, and by thematic content related to food and face-to-face play topics; later acquisition was predicted by features representing frames that select for pronouns and question words, and by content related to narratives and object play.  相似文献   
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