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141.
The main purpose of the current research was to develop an abbreviated form of the Dyadic Adjustment Scale (DAS) with nonparametric item response theory. The authors conducted 5 studies, with a total participation of 8,256 married or cohabiting individuals. Results showed that the item characteristic curves behaved in a monotonically increasing function for all items of the brief 4-item version of the DAS (DAS-4). The DAS-4 proved to be informative at all levels of couple satisfaction. Compared with the 32-item version of the DAS (DAS-32), it was as effective in predicting couple dissolution and was significantly less contaminated by socially desirable responding. In addition, structural equation modeling demonstrated that the underlying latent construct measured by the DAS-4 was very stable over a 2-year period. This brief version has the advantage of being less time consuming and constitutes a promising alternative to the original DAS-32 for clinicians and researchers. 相似文献
142.
Four choice reaction time experiments documented a stimulus-response (S-R) compatibility effect involving the numbers of stimuli
and responses. In Experiment 1, the stimulus consisted of one or two tones, and the correct response was either one or two
taps of a response key. Responses were much faster with a compatible S-R assignment, in which the number of taps matched the
number of tones, than with an incompatible assignment in which these numbers mismatched. Experiments 2 and 3 replicated this
effect, using visual stimuli and bimodal stimuli, respectively, suggesting that auditory/manual rhythmic compatibility is
not essential to it. Experiment 4 showed that an analogous but smaller effect is obtained when stimuli are the digits 1 and
2. This new numerosity-based compatibility effect has general theoretical implications regarding the mechanisms responsible
for compatibility effects and practical implications for interface design. 相似文献
143.
In visual perception, part segmentation of an object is considered to be guided by image-based properties, such as occurrences
of deep concavities in the outer contour. However, object-based properties can also provide information regarding segmentation.
In this study, outer contours and interpretations of object configurations were manipulated to examine differences between
image-based and object-based segmentation in a visual search task. We found that locating a two-dimensional object configuration
with deep concavities in the outer contour depends on the type of outer contour of the surrounding distractors. In addition,
locating a three-dimensional object configuration was harder when it was surrounded by object-based-disconnected distractors,
as compared with object-based-connected distractors, regardless of image-based connections in these distractors. We conclude
that segmentation based on the outer contours of a target facilitates its localization. However, when three-dimensional information
is available, segmentation strongly depends on object-based properties, rather than on image-based properties. 相似文献
144.
Animal models are considered essential in research ensuing elucidation of human disease processes and subsequently, testing of potential therapeutic strategies. This is especially true for neurodegenerative disorders, in which the first steps in pathogenesis are often not accessible in human patients. Alzheimer's disease is vastly becoming a major medical and socioeconomic problem in our aging society. Valid animal models for this uniquely human condition should exhibit histopathological, biochemical, cognitive, and behavioral alterations observed in Alzheimer's disease patients. Major progress has been made since the understanding of the genetic basis of Alzheimer's disease and the development and improvement of transgenic mouse models. All present Alzheimer's disease models developed are partial but nevertheless essential in further unraveling the nature and spatial and temporal development of the complex molecular pathology underlying this condition. One of the more recent transgenic attempts to model Alzheimer's disease is the APP23 transgenic mouse. This article describes the development and assessment of this human amyloid precursor protein overexpression model. We summarize histopathological and biochemical, cognitive and behavioral observations made in heterozygous APP23 mice, thereby emphasizing the model's contribution to clarification of neurodegenerative disease mechanisms. In addition, the first therapeutic interventions in the APP23 model are included. 相似文献
145.
Present optimization techniques in latent class analysis apply the expectation maximization algorithm or the Newton-Raphson
algorithm for optimizing the parameter values of a prespecified model. These techniques can be used to find maximum likelihood
estimates of the parameters, given the specified structure of the model, which is defined by the number of classes and, possibly,
fixation and equality constraints. The model structure is usually chosen on theoretical grounds. A large variety of structurally
different latent class models can be compared using goodness-of-fit indices of the chi-square family, Akaike’s information
criterion, the Bayesian information criterion, and various other statistics. However, finding the optimal structure for a
given goodness-of-fit index often requires a lengthy search in which all kinds of model structures are tested. Moreover, solutions
may depend on the choice of initial values for the parameters. This article presents a new method by which one can simultaneously
infer the model structure from the data and optimize the parameter values. The method consists of a genetic algorithm in which
any goodness-of-fit index can be used as a fitness criterion. In a number of test cases in which data sets from the literature
were used, it is shown that this method provides models that fit equally well as or better than the models suggested in the
original articles. 相似文献
146.
A blank look in reading: the effect of blank space on the identification of letters and words during reading 总被引:1,自引:0,他引:1
Two experiments investigated the effect of visual blank space on reading by varying the amount of interletter and interline blank space in prose passages. Increasing interletter blank spacing slowed the reading process overall, presumably because it disrupted the unitization of words and word identification, but it also improved the identification of the letters within words. By contrast, increasing interline blank spacing sped up the reading process overall, while also improving the identification of words and the letters within words, presumably because the extra spacing reduced the amount of visual information that was processed during reading. The latter finding supports the conclusion that information from surrounding lines of single-spaced text may interfere with reading. 相似文献
147.
Two studies examined the effect of status and liking of the anger target on anger behavior and individual differences in anger-related behavior. Participants recalled anger instances in which the anger target was of higher/equal/lower status and/or liked/ unfamiliar/disliked; subsequently, they indicated which behaviors they had displayed. In both studies, anger behaviors could be grouped into behaviors that imply approaching the target (anger-out, assertion, reconciliation) and behaviors that reflect avoidance/anger-in or social sharing. The results demonstrated that approach behaviors more likely occur toward lower status or liked targets; avoidance behaviors and social sharing more likely occur when the target is of higher status or disliked. On an individual differences level, an approach and an avoid/social sharing person class were identified. The findings suggest that anger may motivate prosocial behavior or social sharing, depending on the individual and type of relation with the target. Only few gender differences were found. 相似文献
148.
This study explored the effects of ageing on working memory by means of the directed forgetting procedure designed by Reed (1970). Memory for a letter trigram was compared in conditions where it was either presented alone (single-item), or followed by a second trigram to be recalled (interference), or followed by a second trigram to be forgotten (directed forgetting). The results clearly indicated that elderly participants inhibited the no-longer-relevant information less efficiently (recall in the single-item condition - recall in the directed forgetting condition), as predicted by the model of Hasher and Zacks (1988). However, the results also demonstrated that sensitivity to interference (recall in the single-item condition - recall in the interference condition) increased in the condition in which no inhibition was directly required. 相似文献
149.
Social disruption (SDR) is an effective model of social stress associated with an enhanced inflammatory reactivity of the immune system. The aim of the present study was to further describe SDR effects on cytokine production by spleen cells, testing selectively monocyte and T cell functions as a result of this stressor. For this purpose, splenocytes from control mice (C) and mice socially stressed for 7 days (SDR) were cultured in the presence of lipopolysaccharide (LPS) or concanavalin A (Con A). Splenocyte proliferation, cytokine production and sensitivity of spleen cells to corticosterone were assessed in vitro. The humoral response to keyhole limpet hemocyanin (KLH) immunization was assessed. SDR induced splenomegaly and enhanced splenocyte basal proliferation. The pro-inflammatory influence of SDR was confirmed by an increased release of interleukin-6 (IL-6) by LPS-stimulated cultures and by a reduced sensitivity of spleen cells to the anti-inflammatory effect of corticosterone. The mechanism increasing cytokine production in response to LPS was cytokine specific, since among inflammatory cytokines, IL-6 but not interferon-gamma (IFN-gamma) was enhanced by stress. In stressed mice, the increase in IL-6 and IFN-gamma and the decrease in IL-10 release in Con A-stimulated cultures indicate that SDR did not modify the Th1/Th2 cytokine balance but globally activated T cells. Plasma anti-KLH antibody levels were similar in both groups. Wounded and non-wounded mice presented similar responses to stress. This study shows that social disruption stress enhances the reactivity of cells from both the acquired and innate immune systems. 相似文献
150.
Changing features do not guide attention in change detection: Evidence from a spatial cuing paradigm
Smilek, Eastwood, and Merikle (2000) demonstrated that the detection of change was facilitated when the target character changed
in many rather than few of its features. Specifically, the function relating search response time to display set size was
shallower when more features changed than when fewer features changed. The researchers interpreted these results as indicating
that large feature changes provide preattentive guidance of focal attention to the location of the change. We tested this
preattentive guidance hypothesis by examining change detection performance in the context of a spatial cuing paradigm. The
hypothesis predicts that (1) the cost on invalidly cued trials should be less when more features change than when fewer features
change, and (2) the features manipulation should have no effect on validly cued trials. In contrast to these predictions,
our results show that cuing effects are equivalent across all levels of feature change and that a robust effect of the features
manipulation is observable for both validly and invalidly cued trials. We argue that large feature changes do not provide
preattentive guidance and in fact can be detected more readilyafter attention is already in place at the target location. 相似文献