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891.
892.
Renate Drechsler Patrizia Rizzo Hans-Christoph Steinhausen 《Child neuropsychology》2013,19(2):145-161
Reward-related processes are impaired in children with ADHD. Whether these deficits can be ascribed to an aversion to delay or to an altered responsiveness to magnitude, frequency, valence, or the probability of rewards still needs to be explored. In the present study, children with ADHD and normal controls aged 7 to 10 years performed a simple probabilistic discounting task. They had to choose between alternatives where the magnitude of rewards was inversely related to the probability of outcomes. As a result, children with ADHD opted more frequently for less likely but larger rewards than normal controls. Shifts of the response category after positive or negative feedback, however, occurred as often in children with ADHD as in control children. In children with ADHD, the frequency of risky choices was correlated with neuropsychological measures of response time variability but unrelated to measures of inhibitory control. It is concluded that the tendency to select less likely but larger rewards possibly represents a separate facet of dysfunctional reward processing, independent of delay aversion or altered responsiveness to feedback. 相似文献
893.
This study aims to clarify the developmental changes in real-life decision making when strategy is adjusted using both positive and negative feedback, that is, whether strategic adjustment evolves with age. A total of 84 participants divided into three age groups (children, adolescents, and adults) performed the standard version of the Iowa Gambling Task (IGT). Children and adolescents showed a strong bias in favor of disadvantageous choices whereas adults learned to decide advantageously during the course of the task. Interestingly, the results clearly demonstrate that children did not switch differently following gains and losses whereas adolescents and adults switched more often after a loss than after a gain, corresponding to the “loss-shift” and the “win-stay” strategies, respectively. The results also revealed that adults switched less often after losses compared to children and adolescents and, thus, used the loss-stay strategy more often than the 2 youngest groups. These new findings suggest that successful completion of the IGT by adults requires fine feedback monitoring and more frequent use of the win-stay and loss-stay strategic adjustments. 相似文献
894.
Jackie L. Micklewright Tricia Z. King Robin D. Morris Mary K. Morris 《Child neuropsychology》2013,19(6):522-527
The Rey Auditory Verbal Learning Test was utilized to examine attention, learning, and memory abilities in 42 children with cerebellar (N?=?18) and third ventricle tumors (N?=?24). Children with cerebellar tumors exhibited significant auditory attentional impairments and displayed adequate encoding and retrieval across subsequent learning and memory trials. In contrast, children with third ventricle tumors exhibited average auditory attentional abilities, but they displayed mild encoding deficits across trials 2–5. Furthermore, the third ventricle group's compromised performance on the delayed recall trial and average performance on the delayed recognition trial is suggestive of underlying retrieval deficits. 相似文献
895.
Eveline A. Crone Silvia A. Bunge Heleen Latenstein Maurits W. van der Molen 《Child neuropsychology》2013,19(3):245-263
On a gambling task that models real-life decision making, children between ages 7 and 12 perform like patients with bilateral lesions of the ventromedial prefrontal cortex (VMPFC), opting for choices that yield high immediate gains in spite of higher future losses (Crone &; Van der Molen, 2004). The current study set out to characterize developmental changes in decision making by varying task complexity and punishment frequency. Three age groups (7–9 years, 10–12 years, 13–15 years) performed two versions of a computerized variant of the original Iowa gambling task. Task complexity was manipulated by varying the number of choices participants could make. Punishment frequency was manipulated by varying the frequency of delayed punishment. Results showed a developmental increase in the sensitivity to future consequences, which was present only when the punishment was presented infrequently. These results could not be explained by differential sensitivity to task complexity, hypersensitivity to reward, or failure to switch response set after receiving punishment. There was a general pattern of boys outperforming girls by making more advantageous choices over the course of the task. In conclusion, 7–12-year-old children—like VMPFC patients—appear myopic about the future except when the potential for future punishment is high. 相似文献
896.
A left-handed metamaterial (a YIG/Ag composite with adjustable negative permittivity and permeability) was prepared by an in situ synthesis process, and its characterisation, microstructure, electrical conductivity, dielectric loss and magnetic properties studied. A negative permittivity behaviour with a Fano-like resonance is ascribed to plasma oscillation of delocalised electrons from silver conducting networks. As the silver content increases, the turbine loss increases, which greatly enhances the electromagnetic wave consumption capacity inside the material and leads to a stronger electromagnetic absorption and shielding performance. The dielectric loss near the percolation threshold is due to the combined effects of polarisation and conduction. The capacitive character is responsible for positive permittivity, and the inductive character leads to negative permittivity. LC resonance results in the Fano-like resonance, leading to the permittivity changing from negative to positive. Gyromagnetic spin rotation, domain wall motion and percolation characteristic of YIG/Ag composites cause frequency dispersion of the permeability. The YIG/Ag composite with double negative characteristics provides prospects for electromagnetic shielding application. 相似文献
897.
Human sensitivity for social cues is exquisite, as illustrated by the ease with which simplified point-light movements invoke social and emotional responses. Compared to faces, these biological motion stimuli only recently started to be used to explore questions regarding social cognition and anxiety. We presented human point-light walkers that could be perceived as facing towards or facing away from the observer, and tested whether participants with high social anxiety would perceive these bistable stimuli differently, because this type of stimuli has particular relevance for them. The results showed that observers with high social anxiety tended to see walkers as facing away more frequently than those with low social anxiety. This may mean that high socially anxious observers are biased towards the more positive perceptual alternative because they are motivated to protect themselves against threatening social experiences, but we also explore alternative explanations. The findings are in line with the evidence for a positivity bias in perception, also called wishful seeing, but in contrast with the attentional negativity bias often found in social anxiety. We discuss reasons for this divergence and possible limitations of the current study. 相似文献
898.
The concept of habitus designates a cognitive structure that is socially embedded and can give valuable insight into the social influences on career choice. A study investigating the relationship of habitus to career choice is presented in a sample of Icelandic youth aged 19–22 (N = 476). Measures of habitus were developed on the basis of reported cultural and leisure activities. The analysis of leisure and cultural items progressed in two steps: factor analysis and cluster analysis. The clusters constitute the four different habitus groups: Pop and fashion, Sports and rock, Music, and Literature. Correspondence factor analysis showed that the habitus groups (clusters) were related to other social variables, such as gender and class; validating habitus theory. Additionally, habitus measures were strongly linked to career variables, such as occupational perception and preferred future occupation. The results support previous research in showing that habitus theory is relevant to career counseling theory and can be a basis of understanding the relationship between social structure and career choice. 相似文献
899.
Individual, situational, and socio-demographic variables from the employee development literature were combined with theory and research on career success in a ten-year study of 289 workers from across many jobs and industries in the workforce. Support for employee development by one's employer ten years prior and a trend of increasing/accumulating support contributed to career success, providing the first long-term confirmation of the value to careers from support for development by employers. Proactive personality had unique effects on success not accounted for by a broad array of other variables, strengthening conclusions from prior research about the predictive value of proactive personality which were based on data not controlling for these variables. Finally, achievement goal orientation influenced success in a unique way via “profile effects:” Goal orientation dimensions interacted to predict success, suggesting simple linear effects (e.g. being more learning-oriented) may be inadequate in explaining career success. Implications for future research and practice are discussed. 相似文献
900.
Andrea N. Niles Bita Mesri Lisa J. Burklund Matthew D. Lieberman Michelle G. Craske 《Behaviour research and therapy》2013
Cognitive behavioral therapy (CBT) is a well-established treatment for anxiety disorders, and evidence is accruing for the effectiveness of acceptance and commitment therapy (ACT). Little is known about factors that relate to treatment outcome overall (predictors), or who will thrive in each treatment (moderators). The goal of the current project was to test attentional bias and negative emotional reactivity as moderators and predictors of treatment outcome in a randomized controlled trial comparing CBT and ACT for social phobia. Forty-six patients received 12 sessions of CBT or ACT and were assessed for self-reported and clinician-rated symptoms at baseline, post treatment, 6, and 12 months. Attentional bias significantly moderated the relationship between treatment group and outcome with patients slow to disengage from threatening stimuli showing greater clinician-rated symptom reduction in CBT than in ACT. Negative emotional reactivity, but not positive emotional reactivity, was a significant overall predictor with patients high in negative emotional reactivity showing the greatest self-reported symptom reduction. 相似文献