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991.
992.
Our objective was to characterize individual differences in fear conditioning and extinction in an outbred rat strain, to test behavioral predictors of these individual differences, and to assess their heritability. We fear-conditioned 100 Long-Evans rats, attempted to extinguish fear the next day, and tested extinction recall on the third day. The distribution of freezing scores after fear conditioning was skewed, with most rats showing substantial freezing; after fear extinction, the distribution was bimodal with most rats showing minimal freezing, but a substantial portion showing maximal freezing. Longer rearing episodes measured prior to conditioning predicted less freezing at the beginning of extinction, but differences in extinction learning were not predicted by any baseline exploratory behaviors. We tested the heritability of extinction differences by breeding rats from the top and bottom 20 % of freezing scores during extinction recall. We then ran the offspring through the same conditioning/extinction procedure, with the addition of recording ultrasonic vocalizations throughout training and testing. Only a minority of rats emitted distress vocalizations during fear acquisition, but the incidence was less frequent in the offspring of good extinguishers than in poor extinguishers or randomly bred controls. The occurrence of distress vocalizations during acquisition predicted higher levels of freezing during fear recall regardless of breeding line, but the relationship between vocalization and freezing was no longer evident following extinction training, at which point freezing levels were influenced only by breeding and not by vocalization. The heritability (h 2) of extinction recall was estimated at 0.36, consistent with human estimates.  相似文献   
993.
This functional magnetic resonance imaging (fMRI) study directly compared the neurocircuitry involved in three different attentional strategies during affective picture processing. We exposed 40 participants (20 men, 20 women) to images depicting dental treatment, as well as neutral scenes. They were asked to do one of three tasks while watching the same pictures: directing their attention toward a foreground object within the picture (distraction), classifying whether the image showed dental treatment, or deciding whether the scene elicited fear of pain (introspection). The participants performed the distraction and classification task with high accuracy and rated only 11 % of the dental treatment pictures as pain relevant. Introspection was associated with increased activation of the dorsomedial prefrontal cortex (DMPFC), relative to the two other conditions. Since the dental, relative to the neutral, pictures elicited enhanced DMPFC activation across all conditions, this underlines the role of this brain region for the assignment, as well as self-reference, of affective meaning. Moreover, self-reported dental anxiety was positively correlated with activation of a pain modulatory network (DMPFC, basal ganglia) when the participants focused on the pain relevance of the dental treatment cues. For future studies, it seems promising to study a high-anxious group or even patients afflicted with dental phobia.  相似文献   
994.
In this study we examine two assumptions that underlie the hypothesis that the outcomes of children with emotional disturbances are negatively affected by the loss of access to mental health services during their transitions to adulthood. The first is that children access mental health services during the pre-transition years, and the second is that these services are effective in reducing poor outcomes. We tested these assumptions using children who lost Medicaid enrollment between their 18th and 20th birthdays in Florida’s Medicaid program using arrests as the outcome. All children with an emotional disturbance received at least one outpatient service. However, while the mean days of service per month were 3, more than half the children received less than one day of service. Fifty-six percent of children received some psychotherapeutic medication treatment. Children with ADHD had the highest number of days of medication per month in both univariate and multivariate analysis. In multivariate analysis, children with disruptive behavior disorders had significantly more days per month of outpatient services than children with any other diagnoses except anxiety disorders. Medication days but not outpatient service days were negatively associated with arrests. Post hoc analysis suggested that children with ADHD who had high medication days had significantly fewer arrests than children with disruptive behavior disorders. This was not the case for children with ADHD and low medication days. Children with ADHD and high medication use may be most at risk of increases in arrests after Medicaid disenrollment as many will lose access to a service that was associated with fewer arrests. Findings suggest the need for reform of the children’s mental health system.  相似文献   
995.
The current study examined whether cognitive and social processing variables mediated the relationship between fear network and depression among parents of children undergoing hematopoietic stem cell transplant (HSCT). Parents whose children were initiating HSCT (N = 179) completed survey measures including fear network, Beck Depression Inventory, cognitive processing variables (positive reappraisal and self-blame) and social processing variables (emotional support and holding back from sharing concerns). Fear network was positively correlated with depression (p < .001). Self-blame and holding back emerged as individual partial mediators in the relationship between fear network and depression. Together they accounted for 34.3 % of the variance in the relationship between fear network and depression. Positive reappraisal and emotional support did not have significant mediating effects. Social and cognitive processes, specifically self-blame and holding back from sharing concerns, play a negative role in parents’ psychological adaptation to fears surrounding a child’s HSCT.  相似文献   
996.
In this article, the author first deals with an overview of the socio-demographic characteristics of the Muslim community in Canada, especially in Quebec, and of its educational experiences in Quebec schools. She then analyzes in more depth three important controversies that have targeted the Muslim community in the last 20 years, respectively, regarding the teaching of Arabic at the end of the 1980s, the wearing of the Muslim veil in the mid-1990s and the wider reasonable accommodation debate, which did not specifically target it, in 2007–2008. In the third part based on a major survey of Quebec schools, she, nevertheless, argues that to some extent, these controversies have permitted to foster, to a certain degree, the adaptation of public schools to Muslim students’ needs.  相似文献   
997.
Brain activation associated with anhedonic depression and co-occurring anxious arousal and anxious apprehension was measured by fMRI during performance of an emotion word Stroop task. Consistent with EEG findings, depression was associated with rightward frontal lateralization in the dorsolateral prefrontal cortex (DLPFC), but only when anxious arousal was elevated and anxious apprehension was low. Activity in the right inferior frontal gyrus (IFG) was also reduced for depression under the same conditions. In contrast, depression was associated with more activity in the anterior cingulate cortex (dorsal ACC and rostral ACC) and the bilateral amygdala. Results imply that depression, particularly when accompanied by anxious arousal, may result in a failure to implement top-down processing by appropriate brain regions (left DLPFC, right IFG) due to increased activation in regions associated with responding to emotionally salient information (right DLPFC, amygdala).  相似文献   
998.
Stanley and Williamson (The Journal of Philosophy 98(8), 411–444 2001) reject the fundamental distinction between what Ryle once called ‘knowing-how’ and ‘knowing-that’. They claim that knowledge-how is just a species of knowledge-that, i.e. propositional knowledge, and try to establish their claim relying on the standard semantic analysis of ‘knowing-how’ sentences. We will undermine their strategy by arguing that ‘knowing-how’ phrases are under-determined such that there is not only one semantic analysis and by critically discussing and refuting the positive account of knowing-how they offer. Furthermore, we argue for an extension of the classical ‘knowing-how’/‘knowing-that’-dichotomy by presenting a new threefold framework: Using some core-examples of the recent debate, we will show that we can analyze knowledge situations that are not captured by the Rylean dichotomy and argue that, therefore, the latter has to be displaced by a more fine-grained theory of knowledge-formats. We will distinguish three different formats of knowledge we can have of our actions, namely (1) propositional, (2) practical, and (3) image-like formats of knowledge. Furthermore, we will briefly analyze the underlying representations of each of these knowledge-formats.  相似文献   
999.
We ask whether attentional guidance from working memory (WM) is influenced by the size of an attentional window. Participants adopted either a focused or a diffuse attentional window when responding to a search display. Prior to the search display an initial cue had to be held in memory (Experiment 1A, visual WM; Experiment 1C, verbal WM) or merely identified (Experiment 1B, identification). In all cases, search performance was affected by the re-presentation of the cue in the search display, with the cuing effects (either cost or benefit) being larger when the cue was held in memory than when it was merely identified. Critically, the magnitude of the cuing benefit increased when participants adopted a diffuse attentional window. This held for effects that are based on items held in WM and for effects that are based only on item priming. The results suggest that variations in the size of an attentional window modulate top-down (both WM conditions) as well as bottom-up guidance of attention (identification condition).  相似文献   
1000.
The ability of animals to delay gratification is crucial for complex goal-directed action. It may help them in making effective decisions when facing a choice. We tested the ability of nine long-tailed macaques (Macaca fascicularis) to delay gratification in several experiments. In exchange tasks, subjects had to keep a small piece of cookie before returning it to an experimenter in order to get a larger food amount. Results showed that animals could wait between 10 s and 10 min depending on individual and sizes of reward. In another experiment, subjects could immediately give back the initial piece of cookie then wait for the return. Their performances more than doubled, demonstrating the role of consumption inhibition in postponing gratification. Such achievements underscore delays of gratification which until now were not thought possible in monkeys. Finally, subjects were presented with an accumulation of food pieces added at short intervals until they seized them. They mostly waited between 30 s and 1 min, which points at the consistency of our data, compared to those of other studies. Our results indicate that long-tailed macaques anticipated the duration of delays. We may account for their remarkable performances by their achievements in the social context.  相似文献   
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