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841.
Electrocortical evidence indicates that a wave of synaptic proliferation occurs in the frontal lobes around the age of puberty onset. To study its potential influence on cognition, we examined 246 children (10-17 years) and 49 young adults (18-22 years) using a match-to-sample type of task to measure reaction times to assess emotionally related information. Based upon the instruction set, subjects made a yes/no decision about the emotion expressed in a face, a word, or a face/word combination presented tachistoscopically for 100 ms. The faces were images of a single individual with a happy, angry, sad or neutral expression. The words were 'happy,' 'angry,' 'sad,' or 'neutral,' In the combined stimulus condition, subjects were asked to decide if the face and word matched for the same emotion. Results showed that compared to the previous year, reaction times were significantly slower for making a correct decision at 11 and 12 years of age in girls and boys, the approximate ages of puberty onset. The peripubertal rise in reaction time declined slowly over the following 2-3 years and stabilized by 15 years of age. Analyses of the performance of 15-17 year olds revealed significantly longer reaction times in females to process both faces and words compared to males. However, this sex difference in late puberty appeared to be transient since it was not present in 18-22 year olds. Given the match-to-sample nature of the task employed, the puberty related increases in reaction time may reflect a relative inefficiency in frontal circuitry prior to the pruning of excess synaptic contacts.  相似文献   
842.
Effects of information specifying the position of an object in a 3-D scene were investigated in two experiments with twelve observers. To separate the effects of the change in scene position from the changes in the projection that occur with increased distance from the observer, the same projections were produced by simulating (a) a constant object at different scene positions and (b) different objects at the same scene position. The simulated scene consisted of a ground plane, a ceiling plane, and a cylinder on a pole attached to both planes. Motion-parallax scenes were studied in one experiment; texture-gradient scenes were studied in the other. Observers adjusted a line to match the perceived internal depth of the cylinder. Judged depth for objects matched in simulated size decreased as simulated distance from the observer increased. Judged depth decreased at a faster rate for the same projections shown at a constant scene position. Adding object-centered depth information (object rotation) increased judged depth for the motion-parallax displays. These results demonstrate that the judged internal depth of an object is reduced by the change in projection that occurs with increased distance, but this effect is diminished if information for change in scene position accompanies the change in projection.  相似文献   
843.
Crowell JA  Andersen RA 《Perception》2001,30(12):1465-1488
The pattern of motion in the retinal image during self-motion contains information about the person's movement. Pursuit eye movements perturb the pattern of retinal-image motion, complicating the problem of self-motion perception. A question of considerable current interest is the relative importance of retinal and extra-retinal signals in compensating for these effects of pursuit on the retinal image. We addressed this question by examining the effect of prior motion stimuli on self-motion judgments during pursuit. Observers viewed 300 ms random-dot displays simulating forward self-motion during pursuit to the right or to the left; at the end of each display a probe appeared and observers judged whether they would pass left or right of it. The display was preceded by a 300 ms dot pattern that was either stationary or moved in the same direction as, or opposite to, the eye movement. This prior motion stimulus had a large effect on self-motion judgments when the simulated scene was a frontoparallel wall (experiment 1), but not when it was a three-dimensional (3-D) scene (experiment 2). Corresponding simulated-pursuit conditions controlled for purely retinal motion aftereffects, implying that the effect in experiment 1 is mediated by an interaction between retinal and extra-retinal signals. In experiment 3, we examined self-motion judgments with respect to a 3-D scene with mixtures of real and simulated pursuit. When real and simulated pursuits were in opposite directions, performance was determined by the total amount of pursuit-related retinal motion, consistent with an extra-retinal 'trigger' signal that facilitates the action of a retinally based pursuit-compensation mechanism. However, results of experiment 1 without a prior motion stimulus imply that extra-retinal signals are more informative when retinal information is lacking. We conclude that the relative importance of retinal and extra-retinal signals for pursuit compensation varies with the informativeness of the retinal motion pattern, at least for short durations. Our results provide partial explanations for a number of findings in the literature on perception of self-motion and motion in the frontal plane.  相似文献   
844.
845.
Using data from 28 countries in four continents, the present research addresses the question of how basic values may account for political activism. Study (N = 35,116) analyses data from representative samples in 20 countries that responded to the 21‐item version of the Portrait Values Questionnaire (PVQ‐21) in the European Social Survey. Study (N = 7,773) analyses data from adult samples in six of the same countries (Finland, Germany, Greece, Israel, Poland, and United Kingdom) and eight other countries (Australia, Brazil, Chile, Italy, Slovakia, Turkey, Ukraine, and United States) that completed the full 40‐item PVQ. Across both studies, political activism relates positively to self‐transcendence and openness to change values, especially to universalism and autonomy of thought, a subtype of self‐direction. Political activism relates negatively to conservation values, especially to conformity and personal security. National differences in the strength of the associations between individual values and political activism are linked to level of democratization.  相似文献   
846.
Many previous studies have linked religiosity to social trust. Yet much of this relation remains insufficiently understood, which is partly due to the fact that religiosity is a multidimensional phenomenon. In this article, we identify several of those dimensions, including the integration in religious communities, the importance of God in people's lives, and the religious context. These dimensions give rise to different mechanisms that produce both trust‐enhancing and trust‐reducing effects. Data from the European Values Survey (2008) were used to test the resulting hypotheses, using multilevel logistic regression models. We conclude that the micro effects are ambivalent: integration in religious communities furthers trust, whereas religious socialization and the importance of God lower trust. On the macro level, we find a strong effect of Protestantism, which is in line with previous studies, but that remains puzzling since the individual‐level difference between Protestants and the other religious traditions was found to be very small. In addition, in contrast to other studies, we found that religious diversity increases social trust.  相似文献   
847.
848.
According to a popular version of social capital theory, civic engagement should produce generalized trust among citizens. We put this theory to the test by examining the causal connection between civic engagement and generalized trust using multiple methods and multiple (prospective) panel datasets. We found participants to be more trusting. This was mostly likely caused by selection effects: the causal effects of civic engagement on trust were very small or nonsignificant. In the cases where small causal effects were found, they turned out not to last. We found no differences across types of organizations and only minor variations across countries.  相似文献   
849.
A land use many‐objective optimization problem for a 1500‐ha farm with 315 paddocks was formulated with 14 objectives (maximizing sawlog production, pulpwood production, milksolids, beef, sheep meat, wool, carbon sequestration, water production, income and Earnings Before Interest and Tax; and minimizing costs, nitrate leaching, phosphorus loss and sedimentation). This was solved using a modified Reference‐point‐based Non‐dominated Sorting Genetic Algorithm II augmented by simulated epigenetic operations. The search space had complex variable interactions and was based on economic data and several interoperating simulation models. The solution was an approximation of a Hyperspace Pareto Frontier (HPF), where each non‐dominated trade‐off point represented a set of land‐use management actions taken within a 10‐year period and their related management options, spanning a planning period of 50 years. A trade‐off analysis was achieved using Hyper‐Radial Visualization (HRV) by collapsing the HPF into a 2‐D visualization capability through an interactive virtual reality (VR)‐based method, thereby facilitating intuitive selection of a sound compromise solution dictated by the decision makers' preferences under uncertainty conditions. Four scenarios of the HRV were considered emphasizing economic, sedimentation and nitrate leaching aspects—giving rise to a triple bottomline (i.e. the economic, environmental and social complex, where the social aspect is represented by the preferences of the various stakeholders). Highlights of the proposed approach are the development of an innovative epigenetics‐based multi‐objective optimizer, uncertainty incorporation in the search space data and decision making on a multi‐dimensional space through a VR‐simulation‐based visual steering process controlled at its core by a multi‐criterion decision making‐based process. This approach has widespread applicability to many other ‘wicked’ societal problem‐solving tasks. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
850.
Somatic symptom disorder (SSD) and illness anxiety disorder (IAD) are two new diagnoses introduced in the DSM-5. There is a need for reliable instruments to facilitate the assessment of these disorders. We therefore developed a structured diagnostic interview, the Health Preoccupation Diagnostic Interview (HPDI), which we hypothesized would reliably differentiate between SSD, IAD, and no diagnosis. Persons with clinically significant health anxiety (n = 52) and healthy controls (n = 52) were interviewed using the HPDI. Diagnoses were then compared with those made by an independent assessor, who listened to audio recordings of the interviews. Ratings generally indicated moderate to almost perfect inter-rater agreement, as illustrated by an overall Cohen’s κ of .85. Disagreements primarily concerned (a) the severity of somatic symptoms, (b) the differential diagnosis of panic disorder, and (c) SSD specifiers. We conclude that the HPDI can be used to reliably diagnose DSM-5 SSD and IAD.  相似文献   
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