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91.
Viewed from the center of projection, a perspective picture presents the pictorial depth information of a scene. Knowing the center of projection, one can reconstruct the depicted scene. Assuming another viewpoint is the center of projection will cause one to reconstruct a transformed scene. Despite these transformations, we appreciate pictures from other viewpoints. The compensation hypothesis states that the visible picture surface allows observers to compensate for transformations by locating the center of projection and experiencing pictorial space from there. We show that observers neither completely compensate for nor experience transformations of space as geometry would predict. We propose a modified compensation hypothesis according to which different degrees of visibility of the picture surface invoke different degrees of compensation.  相似文献   
92.
Children are immature in face recognition, particularly in face configural decoding. This study examines the developmental difference of face recognition in another mechanism: viewpoint transformation processing. Adults and sixth‐grade children were instructed to match a series of one‐tone black face silhouettes to their corresponding front‐view faces. This task involves sophisticated calculation in pictorial information, precise viewpoint transformation, and most probably a 3‐D face representation. The results showed that although the performances were well above chance level in the recognition of familiar faces, for children, they were at chance level in the recognition of unfamiliar faces. The results indicate that children, at least to the age of about 12 years, are still immature in the processing of face viewpoint transformation compared to adults.  相似文献   
93.
This study examined (1) the relative prevalence of childhood abuse and other pathological childhood experiences in China reported by outpatients with borderline personality disorder (BPD), with other personality disorders, and without personality disorders; and, (2) whether the primary predictors of BPD in North America are associated with the development of BPD in China. The childhood experiences of 203 outpatients with BPD, 109 outpatients with other personality disorders, and 70 outpatients without Axis II diagnoses were assessed with the Chinese version of the Childhood Experience of Care and Abuse Questionnaire (CECA.Q). Patients with BPD reported significantly more physical, emotional, and sexual abuse than either comparison group. Four types of childhood experiences were significant predictors of BPD: maternal neglect, paternal antipathy, sexual abuse, and maternal physical abuse. The findings suggest that maternal physical abuse is as strong a predictor of BPD in China as sexual abuse, a finding not replicated in North America.  相似文献   
94.
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   
95.
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   
96.
The roles of previous psychological service use and social network variables in beliefs about psychological services were examined with 184 college students. Having friends and family members who used psychological services, being female, and having used psychological services positively related with beliefs about psychological services. Socioracial differences in the effects of previous use of psychological services and social network variables on students’ beliefs about psychological services were found. Suggestions for ways counselors can provide support to students are discussed.  相似文献   
97.
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   
98.
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   
99.
The effect of spacing in relation to word segmentation was examined for four groups of non-native Chinese speakers (American, Korean, Japanese, and Thai) who were learning Chinese as second language. Chinese sentences with four types of spacing information were used: unspaced text, word-spaced text, character-spaced text, and nonword-spaced text. Also, participants' native languages were different in terms of their basic characteristics: English and Korean are spaced, whereas the other two are unspaced; Japanese is character based whereas the other three are alphabetic. Thus, we assessed whether any spacing effects were modulated by native language characteristics. Eye movement measures showed least disruption to reading for word-spaced text and longer reading times for unspaced than character-spaced text, with nonword-spaced text yielding the most disruption. These effects were uninfluenced by native language (though reading times differed between groups as a result of Chinese reading experience). Demarcation of word boundaries through spacing reduces non-native readers' uncertainty about the characters that constitute a word, thereby speeding lexical identification, and in turn, reading. More generally, the results indicate that words have psychological reality for those who are learning to read Chinese as a second language, and that segmentation of text into words is more beneficial to successful comprehension than is separating individual Chinese characters with spaces.  相似文献   
100.
As a result of studies examining factors involved in the learning process, various structural models have been developed to explain the direct and indirect effects that occur between the variables in these models. The objective was to evaluate a structural model of cognitive and motivational variables predicting academic achievement, including general intelligence, academic self-concept, goal orientations, effort and learning strategies. The sample comprised of 341 Spanish students in the first year of compulsory secondary education. Different tests and questionnaires were used to evaluate each variable, and Structural Equation Modelling (SEM) was applied to contrast the relationships of the initial model. The model proposed had a satisfactory fit, and all the hypothesised relationships were significant. General intelligence was the variable most able to explain academic achievement. Also important was the direct influence of academic self-concept on achievement, goal orientations and effort, as well as the mediating ability of effort and learning strategies between academic goals and final achievement.  相似文献   
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