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81.
Several studies have demonstrated age-related declines in general executive function and memory. In this study, we examined cross-sectional and longitudinal age effects in more specific cognitive processes that constitute executive function and memory. We postulated that, whereas some components of executive and memory functions would show age differences and longitudinal declines, other specific abilities would be maintained or even improve with repeated testing. In a sample of individuals ≥55 years old from the Baltimore Longitudinal Study of Aging, we found longitudinal declines in inhibition, manipulation, semantic retrieval, phonological retrieval, switching, and long-term memory over a maximum of 14 years follow-up. In contrast, abstraction, capacity, chunking, discrimination, and short-term memory were maintained or even improved longitudinally, probably due in part to repeated testing. Moreover, whereas several different abilities were correlated across participants' cross-sectional performance, longitudinal changes in performance showed more heterogeneous trajectories. Finally, compared with cross-sectional performance, longitudinal trajectories showed better distinction between participants with and those without later cognitive impairment. These results show that longitudinal cognitive aging of executive and memory functions is not a uniform process but a heterogeneous one and suggest that certain executive and memory functions remain stable despite age-related declines in other component processes. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
82.
Eight studies with data from 2316 students are presented describing the development and preliminary validation of the Physical Appearance Perfectionism Scale (PAPS), a brief measure with two subscales: Worry About Imperfection and Hope For Perfection. Results from exploratory and confirmatory factor analyses confirmed the measure’s two-dimensional structure. Moreover, correlation analyses provided first evidence for the two subscales’ differential validity: Worry About Imperfection showed negative correlations with positive self-perceptions of one’s appearance (e.g., appearance self-esteem) and positive correlations with maladaptive concerns aspects of perfectionism, physical appearance concerns (e.g., body image disturbances), and body weight control whereas Hope For Perfection showed positive correlations with positive striving aspects of perfectionism, positive self-perceptions, and impression management. In addition, all PAPS scores showed high reliability (Cronbach’s alpha) and temporal stability (test-retest). Overall the findings suggest that the PAPS is a reliable and valid instrument to assess positive and negative aspects of physical appearance perfectionism.  相似文献   
83.
Meditation may show differential effects on stress and plasma catecholamines based on genetic polymorphisms in brain-derived neurotrophic factor (BDNF) and catechol O-methyl transferase (COMT). Eighty adults (40 men, 40 women; mean age 26 years) who practiced meditation regularly and 57 healthy control adults (35 men, 22 women; mean age 26 years) participated. Plasma catecholamines (norepinephrine (NE), epinephrine (E), and dopamine (DA)) concentrations were measured, and a modified form of the Stress Response Inventory was administered. The results were analyzed using two-way analysis of covariance (ANCOVA) with control and meditation subjects, gene polymorphism as factors, and meditation duration as the covariate. Two-way ANCOVA showed a significant interaction between control and meditation subjects, and BDNF Val66Met polymorphism on DA/NE+DA/E (p = 0.042) and NE/E+NE/DA (p = 0.046) ratios. A significant interaction was found for control and meditation subjects with COMT Val158Met polymorphism and plasma NE concentrations (p = 0.009). Post hoc ANCOVA in the meditation group, adjusted for meditation duration, showed significantly higher plasma NE concentrations for COMT Met carriers than COMT Val/Val subjects (p = 0.025). Significant differences of stress levels were found between the control and meditation subjects in BDNF Val/Met (p < 0.001) and BDNF Met/Met (p = 0.003), whereas stress levels in the BDNF Val/Val genotype did not differ between the control and meditation groups. This is the first evidence that meditation produces different effects on plasma catecholamines according to BDNF or COMT polymorphisms.  相似文献   
84.
We used 18F-fluorodeoxyglucose small-animal positron-emission tomography to determine whether different styles of coping with stress are associated with different patterns of neuronal activity in the hypothalamus. Adult rats were subjected to immobilization (IMO)-stress or to a non-immobilized condition for 30 min, in random order on separate days, each of which was followed by brain-scanning. Some rats in the immobilized condition were allowed to actively cope with the stress by chewing a wooden stick during IMO, while the other immobilized rats were given nothing to chew on. Voxel-based statistical analysis of the brain imaging data shows that chewing counteracted the stress-induced increased glucose uptake in the hypothalamus to the level of the non-immobilized condition. Region-of-interest analysis of the glucose uptake values further showed that chewing significantly suppressed stress-induced increased glucose uptake in the paraventricular hypothalamic nucleus and the anterior hypothalamic area but not in the lateral hypothalamus. Together with the finding that the mean plasma corticosterone concentration at the termination of the IMO was also significantly suppressed when rats had an opportunity to chew a wooden stick, our results showed that active coping by chewing inhibited the activation of the hypothalamic-pituitary-adrenal axis to reduce the endocrine stress response.  相似文献   
85.
This article introduces a simple survey method to distinguish between two types of variables that affect happiness—type A, which exerts an absolute effect on happiness, and type B, which affects happiness only through social context. The authors validate the method by comparing its findings with the findings of a theoretically superior but less practical experimental method, and use the method to identify the AB nature of a variety of naturally-occurring variables among both college students and people with work experience. We conclude by discussing the limitation of this method as well as its potential to inform policymakers about where to invest resources in order to improve people’s happiness over time.  相似文献   
86.
Many studies have suggested that emotional stimuli orient and engage attention. There is also evidence that animate stimuli, such as those from humans and animals, cause attentional bias. However, categorical and emotional factors are usually mixed, and it is unclear to what extent human context influences attentional allocation. To address this issue, we tracked participants' eye movements while they viewed pictures with animals and inanimate images (i.e., category) as focal objects. These pictures had either negative or neutral emotional valence, and either human body parts or nonhuman parts were near the focal objects (i.e., context). The picture's valence, arousal, position, size, and most of the low-level visual features were matched across categories. The results showed that nonhuman animals were more likely to be attended to and to be attended to for longer times than inanimate objects. The same pattern held for the human contexts (vs. nonhuman contexts). The effects of emotional valence, category, and context interacted. Specifically, in images with a negative valence, focal animals and objects with human context had comparable numbers of gaze fixations and gaze duration. These results highlighted the attentional bias to animate parts of a picture and clarified that the effects of category, valence, and picture context interacted to influence attentional allocation.  相似文献   
87.
Visual distortions of perceived lengths, angles, or forms, are generally known as “geometric–optical illusions” (goi). In the present paper we focus on a class of gois where the distortion of a straight line segment (the “target” stimulus) is induced by an array of non-intersecting curvilinear elements (“context” stimulus). Assuming local target–context interactions in a vector field representation of the context, we propose to model the perceptual distortion of the target as the solution to a minimization problem in the calculus of variations. We discuss properties of the solutions and reproduction of the respective form of the perceptual distortion for several types of contexts. Moreover, we draw a connection between the interactionist model of gois and Riemannian geometry: the context stimulus is understood as perturbing the geometry of the visual field from which the illusory distortion naturally arises. The approach is illustrated by data from a psychophysical experiment with nine subjects and six different contexts.  相似文献   
88.
Within contemporary Western (post) modern societies, loneliness is seen as a problem that is particularly associated with old age. Much less attention has been given to examining variations in loneliness across age groups. We examine patterns of loneliness across adults aged 15 years and older in the United Kingdom using data from the European Social Survey. We first consider the prevalence of loneliness among the adult population; then the relationship between loneliness and a range of key risk factors, and finally the relationship with age for each of our risk factors. Loneliness demonstrates a nonlinear U-shaped distribution, with those aged under 25 years and those aged over 65 years demonstrating the highest levels of loneliness. Depression is associated with loneliness for all age groups. Poor physical health is associated with loneliness in young adult and midlife but not later life. For those in mid and later life, the quality of social engagement is protective against loneliness, while for young adults it is the quantity of social engagement. This indicates that different factors may endow vulnerability (or protect) against loneliness at different stages of life and suggests that preventative strategies or interventions that reflect these variations need to be developed.  相似文献   
89.
90.
Nanjing University psychologist Liping Yang interviews Kenneth Gergen on the development of social constructionist thought and practice. The conversation treats a variety of issues, including the development of constructionism as a new paradigm, qualitative research, education and other practices informed by constructionism, value loaded science, relativism, and the Taos Institute.  相似文献   
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