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961.
Does trauma exposure have a long-term impact on the brain and behavior of healthy individuals? The authors used functional magnetic resonance imaging to assess the impact of proximity to the disaster of September 11, 2001, on amygdala function in 22 healthy adults. More than three years after the terrorist attacks, bilateral amygdala activity in response to viewing fearful faces compared to calm ones was higher in people who were within 1.5 miles of the World Trade Center on 9/11, relative to those who were living more than 200 miles away (all were living in the New York metropolitan area at time of scan). This activity mediated the relationship between group status and current symptoms of posttraumatic stress disorder. In turn, the effect of group status on both amygdala activation (fearful vs. calm faces) and current symptoms was statistically explained by time since worst trauma in lifetime and intensity of worst trauma, as indicated by reported symptoms at time of the trauma. These data are consistent with a model of heightened amygdala reactivity following high-intensity trauma exposure, with relatively slow recovery.  相似文献   
962.
This article reports a calibration procedure that enables researchers to track movements of the eye while allowing relatively unrestricted head and/or body movement. The eye—head calibration algorithm calculates fixation point based on eye-position data acquired by a head-mounted eyetracker and corresponding head-position data acquired by a 3-D motion-tracking system. In a single experiment, we show that this procedure provides robust eye-position estimates while allowing free head movement. Although several companies offer ready-made systems for this purpose, there is no literature available that makes it possible for researchers to explore the details of the calibration procedures used by these systems. By making such details available, we hope to facilitate the development of cost-effective, nonproprietary eyetracking solutions.  相似文献   
963.
Models of attention and emotion have assigned a special status to the processing of threatening information: Facilitated attentional capture by threat and its prioritized processing would allow for swift and adequate action to potentially dangerous stimuli. In four experiments, we examined the time-course of facilitated orienting of attention to threatening scenes in the exogenous cueing paradigm. Threat value and presentation duration of the cues were systematically varied. Facilitated attentional capture by threat was limited to highly threatening pictures presented for 100 ms. No attentional effects were observed with a 28 ms cue presentation duration. At slightly longer cue presentations, 200 ms and 500 ms, results indicated no and even reduced attentional capture by threat compared with neutral information. The present results provide support for the idea that threat facilitates fast attentional orienting to its location, followed by the inhibition of attention to threat.  相似文献   
964.
According to the preemptive-control hypothesis, participants can specify their control settings to attend to relevant target colours or to ignore the irrelevant distractor colours in advance of the displays. Two predictions of this hypothesis were tested. First, with the control settings being specified in advance, capture by a stimulus that better matches the settings was expected to temporally precede capture by a stimulus that matches the setting less well. Second, with the control settings being specified in advance, stronger capture by the better matching than by the less matching stimulus was predicted not to be a stimulus-driven consequence of the target colour in a preceding trial. Both predictions were shown to hold true under different conditions in three experiments.  相似文献   
965.
The aim of the present study was to investigate Type A behavior as well as perceived work situation, and associations with burnout and work engagement. The associations in focus were investigated through hierarchical regressions in a sample (N= 329) of Swedish Information Communication Technology consultants. The findings indicated that both work situation and Type A behavior was correlated with work engagement and burnout; however, no interactions between Type A behavior and work situation were elicited. The main conclusion was that the achievement striving aspect of Type A behavior appears as "non-toxic" and is related only to work engagement. However, the irritability/impatience aspect appears to be responsible for burnout complaints among Type A individuals, possibly through negative effects of the mood itself than through perceived stress at work.  相似文献   
966.
Tan L  Ward G 《Memory & cognition》2007,35(5):1093-1106
In two experiments, we examined the effect of output order in immediate serial recall (ISR). In Experiment 1, three groups of participants saw lists of eight words and wrote down the words in the rows corresponding to their serial positions in an eight-row response grid. One group was precued to respond in forward order, a second group was precued to respond in any order, and a third group was postcued for response order. There were significant effects of output order, but not of cue type. Relative to the forward output order, the free output order led to enhanced recency and diminished primacy, with superior performance for words output early in recall. These results were replicated in Experiment 2 using six-item lists, which further suggests that output order plays an important role in the primacy effect in ISR and that the recency items are most highly accessible at recall.  相似文献   
967.
Since the 1970s mental health consumer-run organizations have come to offer not only mutual support, but they have also adopted agendas for broader social change. Despite an awareness of the need for system level efforts that create supportive environments for their members, there has been limited research demonstrating how their system level activities can be documented or their impacts evaluated. The purpose of this paper is to feature a method of evaluating systems change activities and impacts. The paper is based on a longitudinal study evaluating four mental health consumer-run organizations in Ontario, Canada. The study tracked system level activities and impacts using both qualitative and quantitative methodologies. The article begins by describing the development and implementation of these methods. Next it offers a critical analysis of the methods used. It concludes by reflecting on three lessons learned about capturing system level activities and impacts of mental health consumer-run organizations.  相似文献   
968.
Although major depressive disorder (MDD) is associated with suicidal behaviors, some depressed individuals are not suicidal and others evidence various forms of suicidality. We thus investigated whether aspects of temperament and self-regulation of dysphoria represent risk factors for DSM-IV suicidality (recurrent thoughts of death, recurrent suicidal ideation, suicidal plan, and suicide attempt) in depressed youths. Using a sample of children with MDD (N = 407; ages 7-14 years), recruited from clinical sites across Hungary, we tested the hypotheses that: (a) suicidality is related to higher levels of trait negative emotionality as well as more maladaptive and fewer adaptive regulatory responses to dysphoria and (b) as the severity of suicidal behavior increases, levels of trait negative emotionality and dysfunctional emotion regulation also increase. We also explored if other aspects of temperament relate to suicidality. Children's DSM-IV diagnoses were based on semi-structured interviews and best-estimate psychiatric consensus. Parents independently provided ratings of their children's temperament, and children separately completed an inventory of emotion regulation (ER). Using multivariate models, we failed to confirm the hypothesized relations of negative trait emotionality and suicidality, but confirmed that high maladaptive and low adaptive ER response tendencies increase the odds of suicidal behaviors, above and beyond the risk posed by depressive illness severity. Unplanned interaction terms between temperament dimensions (other than negative emotionality) and ER suggested that at some high-extremes of temperament, ER has no impact on suicidality but in their absence, adaptive ER lowers the risk of suicidality. The practical implications of the findings are discussed.  相似文献   
969.
Ramsey G  Bastian ML  van Schaik C 《The Behavioral and brain sciences》2007,30(4):393-407; discussion 407-32
Innovation is a key component of most definitions of culture and intelligence. Additionally, innovations may affect a species' ecology and evolution. Nonetheless, conceptual and empirical work on innovation has only recently begun. In particular, largely because the existing operational definition (first occurrence in a population) requires long-term studies of populations, there has been no systematic study of innovation in wild animals. To facilitate such study, we have produced a new definition of innovation: Innovation is the process that generates in an individual a novel learned behavior that is not simply a consequence of social learning or environmental induction. Using this definition, we propose a new operational approach for distinguishing innovations in the field. The operational criteria employ information from the following sources: (1) the behavior's geographic and local prevalence and individual frequency; (2) properties of the behavior, such as the social role of the behavior, the context in which the behavior is exhibited, and its similarity to other behaviors; (3) changes in the occurrence of the behavior over time; and (4) knowledge of spontaneous or experimentally induced behavior in captivity. These criteria do not require long-term studies at a single site, but information from multiple populations of a species will generally be needed. These criteria are systematized into a dichotomous key that can be used to assess whether a behavior observed in the field is likely to be an innovation.  相似文献   
970.
Performance-avoidance goals (the desire to avoid performing more poorly than others do) have been shown to have consistently deleterious effects on performance but the effects of performance-approach goals (trying to outperform others) are more complex. Two studies examine uncertainty as a moderator of the effect of performance-approach goals on performance. Experiment 1 shows that manipulated performance-approach goals lead to better performance than do performance-avoidance goals in the absence of uncertainty about performance but when participants learn that a coactor disagreed with them about problem solutions, creating uncertainty, performance-approach goals do not differ from performance-avoidance goals in their effect on performance. Experiment 2 shows that uncertainty also moderates the effects of self-set performance-approach goals. Moreover, the same dynamic occurs with another kind of uncertainty: negative competence feedback.  相似文献   
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