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811.
The present research examined the developmental course of racial behaviours in childhood. It tested the hypothesis that White children's expressions of racial prejudice do not necessarily decline in middle childhood due to the development of particular cognitive skills but that instead, as argued by the socio-normative approach, children older than seven will go on expressing prejudiced attitudes under appropriate conditions. This would be explained by the presence of an anti-racism norm, along with the existence of values promoting equal rights, which impede blatant expressions of racism. In the first study 283 White children aged 6-7 and 9-10 years performed a task of resource allocation to White and Black target children in conditions of high (White interviewer was present) or low (White interviewer was absent) salience of the anti-racist norm. The 6- to 7-year-old children discriminated against the Black target in both conditions whereas older children discriminated against the Black child only when the anti-racist norm was not salient. In Study 2, 187 White children aged 6-7 and 9-10 years performed the same resource allocation task in conditions of explicit activation of similarity vs dissimilarity or egalitarian vs merit-based norms regarding race relations. Supporting the hypothesis of the role of racist or anti-racist norms on the expression of intergroup discrimination, results have again shown that 6- to 7-year-old children discriminated against the Black target in both conditions while older children presented significantly different prejudiced/nonprejudiced behaviours consistent with the activated norms. These results were discussed in terms of the need for a reanalysis of the assumptions and research results of the cognitive-developmental theory and of further developments in the socio-normative approach regarding the development of prejudice in childhood.  相似文献   
812.
The study of risk and religiosity is fundamentally about gender differences in religiosity. Gender scholars would be highly critical about this debate because it ignores questions about the size and universality of gender effects, there is little or no attempt to conceptualize and measure risk preference, and because it does not take into account gendering processes.  相似文献   
813.
The main objective of the present study was to examine the role of motivation and action orientation in forming spontaneous (i.e., without specific instruction or manipulation) implementation intentions for a healthy diet goal. We hypothesized that (1) the adoption of a diet goal would be determined by (either intrinsic or extrinsic) motivation only whereas, (2) forming implementation intentions would be determined by intrinsic motivation and (either low or high) action orientation. These hypotheses were addressed in a sample of 142 normal weight subjects who were concerned about their dietary habits. Primary outcomes were goal intentions and implementation intentions. Our hypothesis regarding the prediction of goal intentions was confirmed whereas results relating to the prediction of implementation intentions demonstrated that intrinsic motivation and low (but not high) action orientation proved significant predictors of intentions to implement a healthy diet goal. These findings suggest that self‐regulatory skills as assessed by the concept of action orientation may relate to short‐term strategies of initiating behavior change only. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
814.
Various studies suggest that movement sequences are initially learned predominantly in effector-independent spatial coordinates and only after extended practice in effector-dependent coordinates. The present study examined this notion for the discrete sequence production (DSP) task by manipulating the hand used and the position of the hand relative to the body. During sequence learning in Experiment 1, in which sequences were executed by reacting to key-specific cues, hand position appeared important for execution with the practiced but not with the unpracticed hand. In Experiment 2 entire sequences were executed by reacting to one cue. This produced similar results as in Experiment 1. These experiments support the notion that robustness of sequencing skill is based on several codes, one being a representation that is both effector and position dependent.  相似文献   
815.
816.
Violence was shown to be qualitatively different from functional hyper‐aggression in mice selected for high aggression namely Short Attack Latency (SAL), Turku Aggressive (TA) and North Carolina (NC900) strains. This study aimed at investigating whether this adulthood violent phenotype as seen previously in the SAL mice is fixed and hence behaviorally inflexible right from day 1 of the experiment or consequential, i.e., subject to gradual change from functional aggression to violence. The functionally hyper‐aggressive strains namely TA and NC900 strains served as controls for the study. Methodologically, behavioral (in)flexibility was studied using the overall sequential structure of agonistic behavior. In particular, intra‐individual variations in the overall agonistic behavior as well as offensive, pre‐ and post‐offensive behavior transitions, directly related to the resident–intruder interactions were investigated. The SAL mice showed the least intra‐individual variation in their overall sequential agonistic structure as well as a fixed offense‐oriented agonistic behavior of highest magnitude when compared with the other strains. Additionally, the pre‐ and post‐ offensive transitions were most salient in the functionally hyper‐aggressive TA and NC900 strains, whereas virtually absent in the SAL mice. Thus, the violent behavior of the adult SAL mice is behaviorally inflexible or fixed, whereas the functionally hyper‐aggressive behavior of the adult TA and NC900 mice is behaviorally flexible and constantly adaptive to the opponent behavior, over 3 days of repeated resident–intruder interaction. Aggr. Behav. 35:430–436, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
817.
Little direct evidence has emerged regarding the influence of switching between tasks on the performance of skills studied in the motor domain. The present study reported the results of two experiments that examined the effects of task switching on a simple object projection task, which presumably emphasized processes related to response planning and execution. The experimental task required participants to gently tap a knob to make it travel along two parallel rods until it reached a specified target distance. In both experiments, participants in the repeated conditions performed a single target distance while participants in the switched conditions alternated between two target distances. Results indicated that switching between targets degraded accuracy for the two short targets (30cm, Exp. 1; 20cm, Exp. 2). Results were consistent with the preservation of parameter values [Rosenbaum, D. A., Weber, R. J., Hazelett, W. M., & Hindorff, V. (1986). The parameter remapping effect in human performance. Evidence form tongue twisters and finger fumblers. Journal of Memory and Language, 25, 710-725; Sherwood, D. E. (2007). Separate movement planning and spatial assimilation effects in sequential bimanual aiming movements. Perceptual and Motor Skills, 105, 501-513] and suggested an additional role for persisting activation in accounting for spatial assimilation and magnitude effects.  相似文献   
818.
We often feel that our perceptual experience is richer than what we can express. For instance, when flashed with a large set of letters, we feel that we can see them all, while we can report only a few. However, the nature of this subjective impression remains highly debated: while many favour a dissociation between two forms of consciousness (access vs. phenomenal consciousness), others contend that the richness of phenomenal experience is a mere illusion. Here we addressed this question with a classical partial-report paradigm now modified to include unexpected items in the unreported parts of the stimuli. We show that even in the presence of unexpected pseudo-letters, participants still felt that there were only letters. Additionally, we show that this feeling reflects an illusion whereby participants reconstruct letters using partial letter-like information. We propose that the feeling of seeing emerges from the interplay between partially accessible information and expectations.  相似文献   
819.
Investigations using invertebrate species have led to a considerable progress in our understanding of the mechanisms underlying learning and memory. In this review we describe the main behavioral and neuronal findings obtained by studying the habituation of the escape response to a visual danger stimulus in the crab Chasmagnathus granulatus. Massed training with brief intertrial intervals lead to a rapid reduction of the escape response that recovers after a short term. Conversely, few trials of spaced training renders a slower escape reduction that endures for many days. As predicted by Wagner’s associative theory of habituation, long-term habituation in the crab proved to be determined by an association between the contextual environment of the training and the unconditioned stimulus. By performing intracellular recordings in the brain of the intact animal at the same time it was learning, we identified a group of neurons that remarkably reflects the short- and long-term behavioral changes. Thus, the visual memory abilities of crabs, their relatively simple and accessible nervous system, and the recording stability that can be achieved with their neurons provide an opportunity for uncovering neurophysiological and molecular events that occur in identifiable neurons during learning.  相似文献   
820.
The purpose of this investigation was to assess the reliability and validity of eight developmental asset measures among a stratified, random sample (N = 540) of college students to guide health promotion efforts. The sample was randomly split to produce exploratory and confirmatory samples for factor analysis using principal axis factoring and varimax rotation and structural equation modeling techniques. Items were retained on factors if they had high loadings greater than .40 and were not complex. Concurrent validity was examined among substance use (including alcohol and tobacco) and sexual risk-taking variables. Exploratory and confirmatory samples did not differ on demographics. Parallel analysis confirmed the eight theorized constructs. Exploratory factor loadings were greater than .40. Concurrently, validity analyses were in the predicted direction. Cronbach alphas were .70 or greater with the exception of the Future Aspirations asset. Preliminary analyses support the reliability and validity of measuring developmental assets among emerging adults. Implications and potential uses are discussed.  相似文献   
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