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231.
The pedunculopontine tegmental nucleus (PPTg) is involved in the regulation of thalamocortical transmission and of several functions related to ventral and dorsal striatal circuits. Stimulation of the PPTg in anesthetized animals increases cortical arousal, cortical acetylcholine release, bursting activity of mesopontine dopaminergic cells, and striatal dopamine release. It was hypothetized that PPTg stimulation could improve learning by enhancing cortical arousal and optimizing the activity of striatal circuits. We tested whether electrical stimulation (ES) of the PPTg, applied to freely-moving awake rats previously implanted with a chronic electrode, would improve the acquisition and/or the retention of two-way active avoidance conditioning, and whether this effect would depend on the specific PPTg region stimulated (anterior vs posterior) and on the time of ES: just before (pre-training) or after (post-training) each of three training sessions. The treatment consisted of 20 min of ES (0.2 ms pulses at 100 Hz; current intensity: 40-80 microA). The results showed that (1) this stimulation did not induce either any signs of distress nor abnormal behaviors, apart from some motor stereotyped behaviors that disappeared when current intensity was lowered; (2) pre-training ES applied to the anterior PPTg improved the acquisition of two-way active avoidance, (3) no learning improvement was found after either post-training ES of the anterior PPTg, or pre- and post-training ES of the posterior PPTg. The results give support to a role of PPTg in learning-related processes, and point to the existence of functional PPTg regions.  相似文献   
232.
The authors provide a didactic treatment of nonlinear (categorical) principal components analysis (PCA). This method is the nonlinear equivalent of standard PCA and reduces the observed variables to a number of uncorrelated principal components. The most important advantages of nonlinear over linear PCA are that it incorporates nominal and ordinal variables and that it can handle and discover nonlinear relationships between variables. Also, nonlinear PCA can deal with variables at their appropriate measurement level; for example, it can treat Likert-type scales ordinally instead of numerically. Every observed value of a variable can be referred to as a category. While performing PCA, nonlinear PCA converts every category to a numeric value, in accordance with the variable's analysis level, using optimal quantification. The authors discuss how optimal quantification is carried out, what analysis levels are, which decisions have to be made when applying nonlinear PCA, and how the results can be interpreted. The strengths and limitations of the method are discussed. An example applying nonlinear PCA to empirical data using the program CATPCA (J. J. Meulman, W. J. Heiser, & SPSS, 2004) is provided.  相似文献   
233.
The present study examined how the effects of three audiotapes containing different types of social comparison information on the mood of cancer patients depended on the level of neuroticism. On the procedural tape, a man and woman discussed the process of radiation therapy, on the emotion tape, they focussed on emotional reactions to their illness and treatment, while on the coping tape they focussed on the way they had been coping. A validation study among 115 students showed that the tapes were perceived as they were intended. The main study was conducted among 226 patients who were about to undergo radiation therapy. Compared to patients in the control group, as patients were higher in neuroticism, they reported less negative mood after listening to the procedural and the coping tape. Furthermore, as patients were higher in neuroticism, they reported less negative mood after listening to the coping tape than to the emotion tape. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
234.
ABSTRACT— Four studies show that the abstract concept of importance is grounded in bodily experiences of weight. Participants provided judgments of importance while they held either a heavy or a light clipboard. Holding a heavy clipboard increased judgments of monetary value (Study 1) and made participants consider fair decision-making procedures to be more important (Study 2). It also caused more elaborate thinking, as indicated by higher consistency between related judgments (Study 3) and by greater polarization of agreement ratings for strong versus weak arguments (Study 4). In line with an embodied perspective on cognition, these findings suggest that, much as weight makes people invest more physical effort in dealing with concrete objects, it also makes people invest more cognitive effort in dealing with abstract issues.  相似文献   
235.
236.
There has been a recent surge of interest in a type of thinking seen in some patients most of the time, and all patients some of the time. In the past it was simply called regressive thinking, but attempts to be more specific have led it to be called by various names, like 'pre-symbolic', 'pre-conceptual' and 'pre-operational'. What these labels attempt to capture is that the patient's thinking, at these times, is without representations and closer to actions. As a clinical phenomena I prefer to use Loewald's term, 'action–language', that is, where words become attempts to bore, seduce, anger, etc. It is different from when words are used to communicate internal states via free association. A case is made for action–language being the primary method by which the unconscious speaks to us in psychoanalytic treatment. This paper explores some of the reasons for this type of thinking, along with the clinical methods to find the thinker where there appears to be none. Distinctions will be made as to the use of the process versus the content, on the goal of interventions as bringing insight versus the capacity for insightfulness, and the model of treatment as leading to transformations in thinking, rather than lifting of repressions. A clinical example is presented to demonstrate these perspectives.  相似文献   
237.
The present study investigates the effects of different types of concurrent feedback on the acquisition of perceptual-motor skills. Twenty participants walked through virtual corridors in which rhythmically opening and closing sliding doors were placed. The participants aimed to adjust their walking speed so as to cross the doors when the doors were close to their maximal aperture width. The highest level of performance was achieved by learners who practiced the task with unambiguous self-controlled concurrent feedback, which is to say, by learners who could request that feedback at wish. Practice with imposed rather than self-controlled feedback and practice without concurrent feedback were shown to be less effective. Finally, the way in which the self-controlled concurrent feedback was presented was also found to be of paramount importance; if the feedback is ambiguous, it may even prevent participants from learning the task. Clearly, unambiguous self-controlled feedback can give rise to higher levels of performance than other feedback conditions (compared to imposed schedule) but, depending on the way it is presented, the feedback can also prevent the participants from learning the task.In the discussion it is argued that unambiguous self-controlled concurrent feedback allows learners to more rapidly educate their attention towards more useful perceptual invariants and to calibrate the relation between perceptual invariants and action parameters.  相似文献   
238.
Although the discovery of mutations on BRCA1 and BRCA2 genes associated with high breast cancer risk has given rise to screening and surveillance initiatives, there is little documentation on why high-risk women choose to enter screening programs. The objective of this qualitative study was to develop a detailed understanding of the experiences and decisions that motivate women with increased risk of hereditary breast cancer to participate in the multicentered Quebec experimental breast screening program. Our study involved 21 participants who were either BRCA carriers or at risk and untested. These women were interviewed while participating in the screening program. Our study demonstrates that intensive screening programs may provide valuable reassurance for women with increased familial risk of hereditary breast cancer, who count on early detection and rapid response from professionals if and when a problem arises. Health professionals must take these and others concerns into account to ensure their interventions are most consistent with women’s needs.  相似文献   
239.
The main purpose of this article is to delineate findings from a review of the literature on the empirical basis for the existence of a relationship between Asperger's syndrome (AS) and violence risk. A second aim is to examine whether certain characteristics of the disorder may have a higher violence-triggering potential. Results of this review show that there are very few empirical studies that confirm a stable link between AS and violence. Only 11 studies involving 22 patients and 29 violent incidents met the criteria for inclusion in the review after the search of the literature. However, a qualitative analysis of the studies yielded some indications of possible patterns of dynamics of violence that may prove to be typical of persons with AS. A tentative comparison of AS and psychopathy indicated that there may be qualitative differences in the characteristics of violent behavior between the disorders. Suggestions for further research are presented.  相似文献   
240.
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