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801.
The Implicit Association Test (IAT) was used to investigate automatic fear associations in fear of spiders. Fear associations toward spiders were measured among spider fearful and nonfearful participants (Experiment 1) as well as among nonfearfuls and spider enthusiasts (Experiment 2). It was shown that the IAT is sensitive to personal automatic fear associations and therefore distinguishes between high-fearful, nonfearful, and enthusiastic participants. Moreover, implicit spider associations measured by the IAT predicted avoidance behavior beyond self-reports. The results of Experiment 2 provide additional support for the argument that implicit spider associations are different from general stereotypes or knowledge about spiders.  相似文献   
802.
In order to estimate the effects of affluence on political attitudes, we conducted interviews with 342 people who had won the lottery between 1983 and 2000 in an Eastern state. A parallel survey of the general public was also conducted. Comparing winners of varying amounts, we find that lottery-induced affluence increases hostility toward estate taxes, marginally increases hostility towards government redistribution, but has little effect on broader attitudes concerning economic stratification or the role of government as a provider of social insurance. These results bolster previous findings suggesting that economic self-interest influences policy preferences when policy consequences are perceived as salient. At the same time, the findings suggest the limited influence that material concerns have on one's broad political outlook.  相似文献   
803.
Numerous theoretical models have been proposed to explain motivation in organizational settings. Several authors such as Herzberg, Deci and Ryan distinguish between intrinsic and extrinsic motivation. A new approach to intrinsic motivation (François, 2003) is now developping in France. It consists of considering that “intrinsic motivation” is a social norm. We have tested the normativity of intrinsic motivation in two field studies using the judge's paradigm. The first study was conducted on 52 recruiters, the second was conducted on 25 experts evaluating a project concerning the creation of an organization. Results show that evaluators prefered intrinsically motivated than extrinsically motivated candidates in both studies. Finally evaluators used utilitarians traits to describe intrinsically motivated candidates. This result gives force to a normative interpretation of intrinsic motivation.  相似文献   
804.
This paper describes a neural model of speech acquisition and production that accounts for a wide range of acoustic, kinematic, and neuroimaging data concerning the control of speech movements. The model is a neural network whose components correspond to regions of the cerebral cortex and cerebellum, including premotor, motor, auditory, and somatosensory cortical areas. Computer simulations of the model verify its ability to account for compensation to lip and jaw perturbations during speech. Specific anatomical locations of the model's components are estimated, and these estimates are used to simulate fMRI experiments of simple syllable production.  相似文献   
805.
High synaptic concentrations of dopamine and/or norepinephrine can impair the working memory function of the prefrontal cortex and impede attention and learning. Methylphenidate, a dopamine and norepinephrine transporter blocker known to facilitate these cognitive processes at low doses, was hypothesized to interfere with memory storage at doses that may raise concentrations of these neurotransmitters to systemically disruptive levels. In the present experiments, a dose of 10.0mg/kg of this drug was administered to female and male Long-Evans rats using a novel oral administration procedure designed to model the normal mode of delivery to humans. It was found to interfere with single-trial memory acquisition in a delayed object recognition test, a spontaneous learning task that involves no appetitive or aversive motivator. The time that the rats spent in overt exploration of the to-be-remembered objects during the acquisition trial was not affected, suggesting that the drug may have impaired processes of memory formation independently of interference with attention.  相似文献   
806.
Eighteen healthy young adults underwent event-related (ER) functional magnetic resonance imaging (fMRI) of the brain while performing a visual category learning task. The specific category learning task required subjects to extract the rules that guide classification of quasi-random patterns of dots into categories. Following each classification choice, visual feedback was presented. The average hemodynamic response was calculated across the eighteen subjects to identify the separate networks associated with both classification and feedback. Random-effects analyses identified the different networks implicated during the classification and feedback phases of each trial. The regions included prefrontal cortex, frontal eye fields, supplementary motor and eye fields, thalamus, caudate, superior and inferior parietal lobules, and areas within visual cortex. The differences between classification and feedback were identified as (i) overall higher volumes and signal intensities during classification as compared to feedback, (ii) involvement of the thalamus and superior parietal regions during the classification phase of each trial, and (iii) differential involvement of the caudate head during feedback. The effects of learning were then evaluated for both classification and feedback. Early in learning, subjects showed increased activation in the hippocampal regions during classification and activation in the heads of the caudate nuclei during the corresponding feedback phases. The findings suggest that early stages of prototype-distortion learning are characterized by networks previously associated with strategies of explicit memory and hypothesis testing. However as learning progresses the networks change. This finding suggests that the cognitive strategies also change during prototype-distortion learning.  相似文献   
807.
Investigated whether three self-system beliefs, fear of abandonment, coping efficacy, and self-esteem, mediated the relations of stressors and caregiver-child relationship quality with concurrent and prospective internalizing and externalizing problems in a sample of children who had experienced parental death in the previous 2.5 years. The cross-sectional sample consisted of 340 children ages 7-16 and their surviving parent/current caregiver; the longitudinal analyses employed a subset of this sample that consisted of 100 children and their parents/caregivers who were assessed at three time points. A multirater, multimethod measure of caregiver-child relationship quality and a multirater measure of children's mental health problems were used. The cross-sectional model supported a mediational relation for fear of abandonment, coping efficacy, and self-esteem. The three-wave longitudinal model showed that fear of abandonment at Time 2 mediated the relation between stressors at Time 1 and internalizing and externalizing problems at Time 3. Implications of these findings for understanding the development of mental health problems in parentally bereaved children and designing interventions for this at-risk group are discussed.  相似文献   
808.
The concept of focus can provide a meaningful bridge between theory and practice. The authors' aim in this paper is to demonstrate that for theory to be clinically useful, it should provide a sense of focus and organization for clinical work. They illustrate how their particular use of a self-psychological/intersubjective model leads to an emphasis on what they refer to as "sustained empathic focus." The authors' choice of concepts leads them consistently to stress the patient's subjective experience and emerging vulnerability.  相似文献   
809.
Mild traumatic brain injury (MTBI) is associated with cognitive,affective, and physical sequelae. When symptoms persist for more than 3 months, a diagnosis of Post-Concussion Syndrome (PCS) is often given. The current study tracked symptom development to explore the natural sequelae of MTBI. Twenty-six MTBI patients received a comprehensive neuropsychological assessment at three intervals: within 1 week, at 4 months and at 7 months post-concussion. Based on DSMIV criteria and clinical judgment, two external raters diagnosed five MTBI participants with PCS. Results suggested that aspects of cognitive functioning of the symptomatic MTBI (i.e., PCS) participants were different from matched normal control (NC) subjects, and from the 21 MTBI patients who were asymptomatic, at 4 months. Asymptomatic MTBI participants improved in overall level of functioning from 4 to 7 months, but remained significantly different from NC participants in their reduced verbal fluency and working memory functioning.  相似文献   
810.
Phonological deficits in dyslexia are typically assessed using metalinguistic tasks vulnerable to extraneous factors such as attention and memory. The present work takes the novel approach of measuring phonology using eyetracking. Eye movements of dyslexic children were monitored during an auditory word recognition task in which target items in a display (e.g., candle) were accompanied by distractors sharing a cohort (candy) or rhyme (sandal). Like controls, dyslexics showed slower recognition times when a cohort distractor was present than in a baseline condition with only phonologically unrelated distractors. However, unlike controls, dyslexic children did not show slowed recognition of targets with a rhyme distractor, suggesting they had not encoded rhyme relationships. This was further explored in an overt phonological awareness test of cohort and rhyme. Surprisingly, dyslexics showed normal rhyme performance but poorer judgment of initial sounds on these overt tests. The results implicate impaired knowledge of rhyme information in dyslexia; however they also indicate that testing methodology plays a critical role in how such problems are identified.  相似文献   
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