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141.
Decision makers typically overweight small probabilities and underweight large probabilities. However, there are recent reports that when probability is presented in the form of relative frequencies, this typical pattern reverses. We tested this hypothesis by comparing decision making in two tasks: In one task, probability was stated numerically, and in the other task, it was conveyed through a visual representation. In the visual task, participants chose whether a "stochastic bullet" should be fired at either a large target for a small reward or a small target for a large reward. Participants' knowledge of probability in the visual task was the result of extensive practice firing bullets at targets. In the classical numerical task, participants chose between pairs of lotteries with probabilities and rewards matched to the probabilities and rewards in the visual task. We found that participants' probability-weighting functions were significantly different in the two tasks, but the pattern for the visual task was the typical, not the reversed, pattern. 相似文献
142.
Sandström A Säll R Peterson J Salami A Larsson A Olsson T Nyberg L 《Stress (Amsterdam, Netherlands)》2012,15(5):503-513
Deficits in executive functioning and working memory associated with frontal lobe dysfunction are prominent in depression and work-related long-term sick leave (LTSL). This study used functional magnetic resonance imaging (fMRI) to investigate potential differences in brain activation patterns in these conditions. In addition, the function of the hypothalamic-pituitary-adrenal (HPA) axis was examined and compared between groups. Since there is a clear overrepresentation of women in these diagnostic groups, and to ensure a more homogenous sample population, only women were included. To examine the neural correlates of relevant cognitive processes in patients on sick leave >90 days due to work-related LTSL, recently diagnosed patients with major depression Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV criteria, untreated), and healthy controls (n?=?10, each group), a 2-back working memory task and a visual long-term memory task were administered during fMRI scanning. HPA axis functioning was investigated using a diurnal curve of saliva cortisol and a dexamethasone suppression test. Task performance was comparable among the three groups. Multivariate image analysis revealed that both memory tasks engaged a similar brain network in all three groups, including the prefrontal and parietal cortex. During the 2-back task, LTSL patients had significant frontal hypoactivation compared to controls and patients with depression. Saliva cortisol measurements showed a flattening of the diurnal rythmicity in LTSL patients compared to patients with depression and healthy contols. Taken together, these findings indicate that work stress-related LTSL and major depression are dissociable in terms of frontal activation and diurnal cortisol rhythmicity. 相似文献
143.
Induction of lucid dreams: A systematic review of evidence 总被引:1,自引:0,他引:1
In lucid dreams the dreamer is aware of dreaming and often able to influence the ongoing dream content. Lucid dreaming is a learnable skill and a variety of techniques is suggested for lucid dreaming induction. This systematic review evaluated the evidence for the effectiveness of induction techniques. A comprehensive literature search was carried out in biomedical databases and specific resources. Thirty-five studies were included in the analysis (11 sleep laboratory and 24 field studies), of which 26 employed cognitive techniques, 11 external stimulation and one drug application. The methodological quality of the included studies was relatively low. None of the induction techniques were verified to induce lucid dreams reliably and consistently, although some of them look promising. On the basis of the reviewed studies, a taxonomy of lucid dream induction methods is presented. Several methodological issues are discussed and further directions for future studies are proposed. 相似文献
144.
Elliott AM Mhanni AA Marles SL Greenberg CR Chudley AE Nyhof GC Chodirker BN 《Journal of genetic counseling》2012,21(2):337-344
Telehealth involves the use of information and communications technology to deliver health services to patients over distance.
Canada is well suited to benefit from telehealth since many individuals live in remote, rural and isolated locations. Manitoba
is the easternmost prairie province and MBTelehealth is an active Canadian program that currently has 105 sites in 73 communities.
Although studies of patient satisfaction comparing telehealth to on-site clinical visits have been conducted, a comparative
study of the types of genetics patients seen via these two modalities has not been performed previously. In this study we:
(1) examined the uptake of telehealth in Genetics in Manitoba; (2) contrasted telehealth usage in Genetics with other clinical
programs; and (3) performed a comparative study of the types of Genetics referrals seen in 2008 on-site versus via telehealth.
Results indicate the uptake of telehealth is increasing and has made genetics outreach clinics unnecessary. The Program of
Genetics and Metabolism is consistently one of the top ten utilizers of telehealth within the province. With respect to discipline,
chi square analysis revealed the trends were not significantly different for on-site and telehealth encounters, with prenatal
referrals being the most common and Hereditary Breast and Ovarian Cancer referrals being the least common. Referrals within
each discipline varied depending on the need for fetal assessment and physical examination. Telehealth was utilized regularly
for test results sessions across all disciplines. 相似文献
145.
Bank AM Barr R Calvert SL Parrott WG McDonough SC Rosenblum K 《Journal of child and family studies》2012,21(2):208-216
We describe the association between postpartum depression and the quantity and content of infant media use. Households with
depressed mothers viewed twice as much television as households with non-depressed mothers did, and depressed mothers appeared
to derive comparatively greater pleasure from television viewing. Maternal depression was associated with an increased exposure
to child-directed content by 6–9-month-old infants, although it was not associated with an increased exposure to adult-directed
programming. Depressed mothers also reported being less likely to sit and talk with their children during television use or
to consult outside sources of information about media. This increase in television exposure without corresponding parental
involvement could negatively affect developmental outcomes. 相似文献
146.
Using two clinical samples of patients, the presented studies examined the construct validity of the recently revised Anxiety Sensitivity Index-3 (ASI-3). Confirmatory factor analyses established a clear three-factor structure that corresponds to the postulated subdivision of the construct into correlated somatic, social, and cognitive components. Participants with different primary clinical diagnoses differed from each other on the ASI-3 subscales in theoretically meaningful ways. Specifically, the ASI-3 successfully discriminated patients with anxiety disorders from patients with nonanxiety disorders. Moreover, patients with panic disorder or agoraphobia manifested more somatic concerns than patients with other anxiety disorders and patients with nonanxiety disorders. Finally, correlations of the ASI-3 scales with other measures of clinical symptoms and negative affect substantiated convergent and discriminant validity. Substantial positive correlations were found between the ASI-3 Somatic Concerns and body vigilance, between Social Concerns and fear of negative evaluation and socially inhibited behavior, and between Cognitive Concerns and depression symptoms, anxiety, fear of negative evaluation, and subjective complaints. Moreover, Social Concerns correlated negatively with dominant and intrusive behavior. Results are discussed with respect to the contribution of the ASI-3 to the assessment of anxiety-related disorders. 相似文献
147.
Major brain functions depend on neuronal processes that favor the plasticity of neuronal circuits while at the same time maintaining their stability. The mechanisms that regulate brain plasticity are complex and engage multiple cascades of molecular components that modulate synaptic efficacy. Protein kinases (PKs) and phosphatases (PPs) are among the most important of these components that act as positive and negative regulators of neuronal signaling and plasticity, respectively. In these cascades, the PP protein phosphatase 2B or calcineurin (CaN) is of particular interest because it is the only Ca(2+)-activated PP in the brain and a major regulator of key proteins essential for synaptic transmission and neuronal excitability. This review describes the primary properties of CaN and illustrates its functions and modes of action by focusing on several representative targets, in particular glutamate receptors, striatal enriched protein phosphatase (STEP), and neuromodulin (GAP43), and their functional significance for synaptic plasticity and memory. 相似文献
148.
Some children’s social activities are structured by joint goals. In previous research, the criterion used to determine this was relatively weak: if the partner stopped interacting, did the child attempt to re‐engage her? But re‐engagement attempts could easily result from the child simply realizing that she needs the partner to reach her own goal in the activity (social tool explanation). In two experiments, 21‐ and 27‐month‐old children interacted with an adult in games in which they either did or did not physically need the partner to reach a concrete goal. Moreover, when the partner stopped interacting, she did so because she was either unwilling to continue (breaking off from the joint goal) or unable to continue (presumably still maintaining the joint goal). Children of both age groups encouraged the recalcitrant partner equally often whether she was or was not physically needed for goal attainment. In addition, they did so more often when the partner was unable to continue than when she was unwilling to continue. These findings suggest that young children do not just view their collaborative partners as mindless social tools, but rather as intentional, cooperative agents with whom they must coordinate intentional states. 相似文献
149.
150.
Sandra J. Tanenbaum 《Theoretical medicine and bioethics》2012,33(4):263-277
Poor quality medical care is sometimes attributed to physicians?? unwillingness to act on evidence about what works best. Evidence-based performance standards (EBPSs) are one response to this problem, and they are increasingly employed by health care regulators and payers. Evidence in this instance is judged according to the precepts of evidence-based medicine (EBM); it is probabilistic, and the randomized controlled trial (RCT) is the gold standard. This means that EBPSs suffer all the infirmities of EBM generally??well rehearsed problems with the external validity of research findings as well as the inferential leap from study results in the aggregate to individual patient care. These theoretical weaknesses promise to have a practical impact on the care of patients. To avoid this, EBPSs should be understood as guidelines indicative of average effectiveness rather than standards to be applied in every case. 相似文献