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891.
892.
A joint impact hypothesis on symptom experience is introduced that specifies the role of negative mood and self-focus, which have been considered independently in previous research. Accordingly, negative affect only promotes symptom experience when people simultaneously focus their attention on the self. One correlational study and 4 experiments supported this prediction: Only negative mood combined with self-focus facilitated the experience (see the self-reports in Studies 1, 2a, & 2b) and the accessibility (lexical decisions, Stroop task in Studies 3 & 4) of physical symptoms, whereas neither positive mood nor negative mood without self-focus did. Furthermore, the joint impact of negative mood and self-focused attention on momentary symptom experience remained significant after controlling for the influence of dispositional symptom reporting and neuroticism. 相似文献
893.
Intrusive reexperiencing in posttraumatic stress disorder (PTSD) has been linked to perceptual priming for trauma-related material. A prospective longitudinal study (N = 69) investigated perceptual priming for trauma-related, general threat, and neutral words in assault survivors with and without PTSD, using a new version of the word-stem completion task. Survivors with PTSD showed enhanced priming for trauma-related words. Furthermore, priming for trauma-related words measured soon after the trauma was associated with subsequent PTSD severity at 3, 6, and 9 months. The enhanced priming effect was specific to trauma-related words. Enhanced perceptual priming for traumatic material appears to be one of the cognitive processes operating in PTSD. 相似文献
894.
Coleman SL Brown VR Levine DS Mellgren RL 《Cognitive, affective & behavioral neuroscience》2005,5(4):434-451
This article develops the cognitive—emotional forager (CEF) model, a novel application of a neural network to dynamical processes in foraging behavior. The CEF is based on a neural
network known as the gated dipole, introduced by Grossberg, which is capable of representing short-term affective reactions in a manner similar to Solomon
and Corbit’s (1974) opponent process theory. The model incorporates a trade-off between approach toward food and avoidance
of predation under varying levels of motivation induced by hunger. The results of simulations in a simple patch selection
paradigm, using a lifetime fitness criterion for comparison, indicate that the CEF model is capable of nearly optimal foraging
and outperforms a run-of-luck rule-of-thumb model. Models such as the one presented here can illuminate the underlying cognitive
and motivational components of animal decision making. 相似文献
895.
Kimberly MB Forte AL Carroll JM Feudtner C 《The American journal of bioethics : AJOB》2005,5(1):59-65
Some children living with life-shortening medical conditions may wish to attend school without the threat of having resuscitation attempted in the event of cardiopulmonary arrest on the school premises. Despite recent attention to in-school do-not-attempt-resuscitation (DNAR) orders, no assessment of state laws or school policies has yet been made. We therefore sought to survey a national sample of prominent school districts and situate their policies in the context of relevant state laws. Most (80%) school districts sampled did not have policies, regulations, or protocols for dealing with student DNARs. A similar majority (76%) either would not honor student DNARs or were uncertain about whether they could. Frequent contradictions between school policies and state laws also exist. Consequently, children living with life-shortening conditions who have DNARs may not have these orders honored if cardiopulmonary arrest were to occur on school premises. Coordinated efforts are needed to harmonize school district, state, and federal approaches in order to support children and families' right to have important medical decisions honored. 相似文献
896.
This article reports on the feasibility of using interactive voice response (IVR) technology to obtain daily reports of attitudes
toward alcohol and tobacco use among children 9–13 years of age. Two studies were conducted. The first was an investigation
of the use of IVR technology to obtain daily data from a sample of primary school children over a period of 8 weeks. The second
was an extension of the research to a large sample of primary and secondary school children in urban and rural areas who provided
daily data over a 4-week period. Retention and compliance rates comparable to those obtained with adults were evident in both
studies, supporting the feasibility of this technology with children. The results are discussed in relation to the benefits
of this methodology for health research, particularly for studies of sensitive topics conducted with children and adolescents. 相似文献
897.
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
898.
ProtoMatch is a software tool for integrating and analyzing fixed-location and movement eye gaze and cursor data. It provides
a comprehensive collection of protocol analysis tools that support sequential data analyses for eye fixations and scanpaths
as well as for cursor “fixations” (dwells at one location) and “cursorpaths” (movements between locations). ProtoMatch is
modularized software that integrates both eye gaze and cursor protocols into a unified stream of data and provides an assortment
of filters and analyses. ProtoMatch subsumes basic analyses (i.e., fixation duration, number of fixations, etc.) and introduces
a method of objectively computing the similarity between scanpaths or cursorpaths using sequence alignment. The combination
of filters, basic analyses, and sequence alignment in ProtoMatch provides researchers with a versatile system for performing
both confirmatory and exploratory sequential data analyses (Sanderson & Fisher, 1994). 相似文献
899.
Davis CJ 《Behavior research methods》2005,37(1):65-70
This article describes a Windows program that enables users to obtain a broad range of statistics concerning the properties
of word and nonword stimuli, including measures of word frequency, orthographic similarity, orthographic and phonological
structure, age of acquisition, and imageability. It is designed for use by researchers in psycholinguistics, particularly
those concerned with recognition of isolated words. The program computes measures of orthographic similarity on line, either
with respect to a default vocabulary of 30,605 words or to a vocabulary specified by the user. In addition to providing standard
orthographic neighborhood measures, the program can be used to obtain information about other forms of orthographic similarity,
such as transposed-letter similarity and embedded-word similarity. It is available, free of charge, from the following Web
site: http://www.maccs.mq.edu.au/≈colin/N-Watch/. 相似文献
900.
Semantic features have provided insight into numerous behavioral phenomena concerning concepts, categorization, and semantic
memory in adults, children, and neuropsychological populations. Numerous theories and models in these areas are based on representations
and computations involving semantic features. Consequently, empirically derived semantic feature production norms have played,
and continue to play, a highly useful role in these domains. This article describes a set of feature norms collected from
approximately 725 participants for 541 living (dog) and nonliving (chair) basic-level concepts, the largest such set of norms developed to date. This article describes the norms and numerous statistics
associated with them. Our aim is to make these norms available to facilitate other research, while obviating the need to repeat
the labor-intensive methods involved in collecting and analyzing such norms. The full set of norms may be downloaded from
www.psychonomic.org/archive. 相似文献