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21.
The United States intelligence community has been under intense scrutiny from both inside and outside in the aftermath of September 11. Post mortem assessments of intelligence breakdowns may judge the events as more predictable than was in fact the actual reality. In a troubled world, when threats to national security can materialize very quickly, the intelligence community must be able to effectively and swiftly develop and implement plans to prevent further terrorist attacks on the homeland. Numerous scenarios need to be considered for the management of crisis situations. Intelligence actions must make it more difficult for terrorists to strike at their targets. The war on terror must confront a new generation of enemies who threaten to attack the United States with weapons of mass destruction. This essay will focus on the role of behavioral science and how related reforms within the intelligence community could improve its capability to respond to a huge challenge.  相似文献   
22.
The congruency effect in distracter interference tasks is typically smaller when the previous trial was incongruent as compared to congruent, suggesting the operation of a control process that minimizes the influence of irrelevant stimuli on behavior. However, both the conditions under which this congruency sequence effect (CSE) can be most easily observed without the typical learning and memory confounds, and the control process underlying it, remain controversial. We therefore tested a recent hypothesis that the CSE is most easily observed without the typical confounds when the distracter is processed before the target. In line with this “distracter head start” hypothesis, in Experiments 1 and 2 the CSE was larger when the distracter appeared before, relative to with, the target. Further, in Experiment 3, we observed a negative congruency effect after incongruent trials when a long interval separated the distracter from the target, consistent with a modulation of the response engendered by the distracter but not with a shift of attention toward the target. These findings reveal an important determinant of CSE magnitude when the typical learning and memory confounds are absent and new insights into the nature of control processes that contribute to this phenomenon.  相似文献   
23.
Identifying individuals who have Lynch syndrome (LS) involves a complex diagnostic work up that includes taking a detailed family history and a combination of various genetic and immunohistochemical tests. The National Society of Genetic Counselors (NSGC) and the Collaborative Group of the Americas on Inherited Colorectal Cancer (CGA-ICC) have come together to publish this clinical practice testing guideline for the evaluation of LS. The purpose of this practice guideline is to provide guidance and a testing algorithm for LS as well as recommendations on when to offer testing. This guideline does not replace a consultation with a genetics professional. This guideline includes explanations in support of this and a summary of background data. While this guideline is not intended to serve as a review of LS, it includes a discussion of background information on LS, and cites a number of key publications which should be reviewed for a more in-depth understanding of LS. These guidelines are intended for genetic counselors, geneticists, gastroenterologists, surgeons, medical oncologists, obstetricians and gynecologists, nurses and other healthcare providers who evaluate patients for LS.  相似文献   
24.
Convergence of the expectation-maximization (EM) algorithm to a global optimum of the marginal log likelihood function for unconstrained latent variable models with categorical indicators is presented. The sufficient conditions under which global convergence of the EM algorithm is attainable are provided in an information-theoretic context by interpreting the EM algorithm as alternating minimization of the Kullback–Leibler divergence between two convex sets. It is shown that these conditions are satisfied by an unconstrained latent class model, yielding an optimal bound against which more highly constrained models may be compared.  相似文献   
25.
Prior work has revealed that posttraumatic stress disorder (PTSD) is associated with altered (a) attentional performance and (b) resting-state functional connectivity (rsFC) in brain networks linked to attention. Here, we sought to characterize and link these behavioral and brain-based alterations in the context of Posner and Peterson’s tripartite model of attention. Male military veterans with PTSD (N = 49; all deployed to Iraq or Afghanistan) and healthy age-and-gender-matched community controls (N = 26) completed the Attention Network Task. A subset of these individuals (36 PTSD and 21 controls) also underwent functional magnetic resonance imaging (fMRI) to assess rsFC. The behavioral measures revealed that the PTSD group was impaired at disengaging spatial attention, relative to the control group. FMRI measures further revealed that, relative to the control group, the PTSD group exhibited greater rsFC between the salience network and (a) the default mode network, (b) the dorsal attention network, and (c) the ventral attention network. Moreover, problems with disengaging spatial attention increased the rsFC between the networks above in the control group, but not in the PTSD group. The present findings link PTSD to both altered orienting of spatial attention and altered relationships between spatial orienting and functional connectivity involving the salience network. Interventions that target orienting and disengaging spatial attention may be a new avenue for PTSD research.  相似文献   
26.
In the present study, we investigated whether involuntarily directing attention to a target-colored distractor causes the corresponding attentional set to enter a limited-capacity focus of attention, thereby facilitating the identification of a subsequent target whose color matches the same attentional set. As predicted, in Experiment 1, contingent attentional capture effects from a target-colored distractor were only one half to one third as large when subsequent target identification relied on the same (vs. a different) attentional set. In Experiment 2, this effect was eliminated when all of the target colors matched the same attentional set, arguing against bottomup perceptual priming of the distractor’s color as an alternative account of our findings. In Experiment 3, this effect was reversed when a target-colored distractor appeared after the target, ruling out a feature-based interference account of our findings. We conclude that capacity limitations in working memory strongly influence contingent attentional capture when multiple attentional sets guide selection.  相似文献   
27.
The assessment and management of pain is a significant public health problem in the United States. Long-term care facilities face unique barriers and challenges to pain management due to the large population of cognitively impaired residents, little physician contact and poor pain education for nurses and nurse assistants. In addition, common misconceptions about pain and pain treatment in the elderly along with health professional and resident fears of addiction and drug toxicity, add to the problem of pain management. The basic principles of pain treatment in long-term care are identical to all other health care settings – utilizing a combination of drug and non-drug treatments. Recent efforts to institutionalize improved pain management practices, through assessment procedures and defined pain management policies, standards and education programming, is a promising venue for systemically improving pain treatment in long-term care settings.  相似文献   
28.
Mental health professionals are frequently called upon to conduct psychological evaluations of the adult parties and minor children in contested child custody actions. Whether Court-appointed or as an agreed examiner, the professional's essential role is that of expert consultant to the court. He or she can only assist the trier of fact by conducting an evaluation that is fair, impartial and objective, that protects the personal and legal rights of all parties, and that is consistent with professional and ethical standards. Ethical principles require the mental health professional to accept the burden of responsibility for protecting and preserving the clients' rights and welfare throughout the evaluation period, from the initial referral to the rendering of recommendations.  相似文献   
29.
Five groups of pigeons were food reinforced on various schedules. Half of each group were extinguished in the normal manner; the others were presented with a stimulus change, previously paired with reinforcement, each time they completed their respective fixed ratios. Response rate in training was an increasing negatively accelerated function of the FR. Increasing the FR produced transitory rate changes, the amount of which yielded a quantitative index of ratio strain. Cumulative records of extinction performance revealed that the stimulus change exerted discriminative control by maintaining the cohesiveness of FR response units. Nevertheless, neither the absolute number of extinction responses nor extinction response units differed appreciably for the two extinction procedures.  相似文献   
30.
Four pigeons were trained on a multiple reinforcement schedule consisting of two limited-hold schedules, one in which a discriminative stimulus (SD) accompanied the periodic reinforcement contingency, and one in which the discriminative stimulus was omitted. The duration of the limited-hold in each component of the multiple schedule was reduced in parallel steps. It was shown that behavioral differences between the two schedules were attenuated by this manipulation of temporal parameters. When SD was reduced in duration, three out of four pigeons responded with extremely high SΔ rates, despite the regular pairing of SΔ with the reinforcement contingency. These high rates qualitatively resembled the rapid rates emitted on the analogous no-SD component.  相似文献   
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