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281.
In this article, the side preferences of feeding-related trunk movements of free-ranging Asian elephants (Elephas maximus) were investigated for the first time. It is hypothesized that a functional asymmetry of the trunk is necessary to perform skillful feeding movements more efficiently. This might be connected with a corresponding hemispheric specialization. Video recordings of 41 wild elephants provided frequencies and durations of the following trunk-movement categories: object contact, retrieval, and reaching. In each category, individual side preferences were found. The strength of side preferences varied between the trunk-movement categories and the sexes. Mean durations of retrieval and reaching correlated negatively with the strength of side biases. Comparing the side preferences in the unpaired trunk with analogous phenomena in other unpaired grasping organs and in primate handedness. the authors discuss possible explanations for the evolution of asymmetries in unpaired grasping organs. 相似文献
282.
This longitudinal study examined memory loss in a sample of 391 initially nondemented older adults. Analyses decomposed observed memory loss into decline associated with preclinical dementia, study attrition, terminal decline, and chronological age. Measuring memory as a function of only chronological age failed to provide an adequate representation of cognitive change. Disease progression accounted for virtually all of the memory loss in the 25% of the sample that developed diagnosable dementia. In the remainder of the sample, both chronological age and study attrition contributed to observed memory loss. These results suggest that much of memory loss in aging adults may be attributable to the progression of preclinical dementia and other nonnormative aging processes that are not captured by chronological age. 相似文献
283.
Character strengths before and after September 11 总被引:3,自引:0,他引:3
Did Americans change following the September 11 terrorist attacks? We provide a tentative answer with respect to the positive traits included in the Values in Action Classification of Strengths and measured with a self-report questionnaire available on-line and completed by 4,817 respondents. When scores for individuals completing the survey in the 2 months immediately after September 11 were compared with scores for those individuals who completed the survey before September 11, seven character strengths showed increases: gratitude, hope, kindness, leadership, love, spirituality, and teamwork. Ten months after September 11, these character strengths were still elevated, although to a somewhat lesser degree than immediately following the attacks. 相似文献
284.
Wilde NJ Strauss E Chelune GJ Hermann BP Hunter M Loring DW Martin RC Sherman EM 《心理评价》2003,15(1):56-63
Five competing models specifying the factor structure underlying the Wechsler Memory Scale-Third Edition (D. Wechsler, 1997b) primary subtest scores were evaluated in a sample of patients with intractable temporal lobe epilepsy (N = 254). Models specifying separate immediate and delayed constructs resulted in inadmissible parameter estimates and model specification error. There were negligible goodness-of-fit differences between a 3-factor model of working memory, auditory memory, and visual memory and a nested--more parsimonious--2-factor model of working memory and general memory. The results suggest that specifying a separate visual memory factor provides little advantage for this sample--an unexpected finding in a population with lateralized dysfunction, for which one might have predicted separate auditory and visual memory dimensions. 相似文献
285.
Howse DJ Squires AS Martin GM Skinner DM 《Learning & memory (Cold Spring Harbor, N.Y.)》2003,10(3):161-167
Rats with perirhinal cortex lesions were compared with sham controls on a conditional discrimination in which saccharin was paired with LiCl in context 1, but paired with saline in context 2. Perirhinal-lesioned rats were slightly slower to acquire the discrimination but reached control levels by the end of acquisition. Both groups showed transfer to familiar tap water, consuming less in context 1 than in context 2. Unlike sham rats, perirhinal rats failed to show an aversion to context 1 on a place choice test. These data provide neuroanatomical support for the postulated difference between Pavlovian conditioning and conditional learning. 相似文献
286.
The utility of the Hospital Anxiety and Depression Scale (HADS) as a screening instrument for anxiety and depression during pregnancy was investigated. A maximum likelihood factor analysis was conducted on the HADS to determine its psychometric properties and utility in 100 women from two culturally diverse populations (UK and Uzbekistan) at 12-weeks and 34-weeks pregnancy. The findings suggest that the HADS lacks the internal reliability requirements of a clinical assessment tool in this population. There was little evidence found to suggest that the HADS measures two dimensions of anxiety and depression consistently and reliably. The findings from this study suggest that the HADS could not be recommended as a clinical screening tool for anxiety and depression in pregnant women. Further research in this area is both desirable and required. 相似文献
287.
288.
Schrepp M 《Journal of mathematical psychology》2001,45(3):480-496
A knowledge domain is represented in knowledge space theory by a finite set Q of problems. The knowledge of a subject in the domain is described by the subset of problems from Q that the subject is able to solve. The set of all possible knowledge states of subjects is called the knowledge structure on Q. A crucial problem is how a hypothetical knowledge structure, obtained for example by querying an expert, can be evaluated empirically. We describe a method for comparing two knowledge structures concerning their ability to describe a set of empirically observed response patterns. Our comparison method is tested in two simulation studies. The results of these studies show that the method is highly accurate in its evaluation of knowledge structures. Copyright 2001 Academic Press. 相似文献
289.
Martin S. Livingston 《Group》2001,25(1-2):15-26
This paper presents one leadership style within a self-psychological approach to working with dreams in group psychotherapy. It stresses an empathic attunement, the creation of safety, and an experience-near playful relationship. Playful is not used lightly here. It is used in the spirit of Winnicott's intermediate space where a mother suspends questions of what is real or not real and what is me and not me. Freud's analogy to a playspace forms a metaphor for the creation of a special atmosphere in a group, or for that matter in individual work as well, that encourages exploration, risk taking, and vulnerability. Working with dreams in this playspace deepens the curative process, not only for the dreamer, but for the entire group. 相似文献
290.
In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met. 相似文献