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851.
852.
In a series of 3 experiments, dogs (Canis familiaris) were presented with variations of the human pointing gesture: gestures with reversed direction of movement, cross-pointing, and different arm extensions. Dogs performed at above chance level if they could see the hand (and index finger) protruding from the human body contour. If these minimum requirements were not accessible, dogs still could rely on the body position of the signaler. The direction of movement of the pointing arm did not influence the performance. In summary, these observations suggest that dogs are able to rely on relatively novel gestural forms of the human communicative pointing gesture and that they are able to comprehend to some extent the referential nature of human pointing.  相似文献   
853.
Predictors of self-reported suicide attempts were studied cross-sectionally and prospectively in order to discern which variables may account for the gender difference in such reports. A representative sample of Norwegian students (N= 9,679) in grades 7-12 were followed from 1992 to 1994. More girls (10.4%) than boys (6.0%) reported a previous attempt and more girls (3.3%) than boys (1.9%) reported an attempt during the study period. The gender difference in previous suicide attempts was significantly reduced when depressed mood was controlled, and was no longer significant when disordered eating was included. There was no gender difference in future attempts when previous attempts, depressed mood, physical appearance, pubertal timing, and romantic involvement were controlled. Girls' higher level of risk factors may account for their higher level of self-reported nonfatal suicidal behavior.  相似文献   
854.
Twelve sleep-deprived and 13 non-deprived Navy cadets were tested with the dichotic listening procedure for effects of sleep deprivation on hemispheric asymmetry and sustained attention. Consonant-vowel syllables were presented to the subjects in three different conditions, a divided (non-forced) attention condition, a forced right ear and a forced left ear attention condition. In the two forced attention conditions the subjects were instructed to focus attention only on the right or left ear stimulus. The results showed an expected right ear advantage for both groups during the non-forced and forced right attention conditions, indicating superior left hemisphere processing. During the forced left attention condition, the sleep-deprived subjects showed no ear advantage at all, while the non-deprived subjects showed an expected left ear advantage. The results are discussed within a theoretical framework of a dual process model, where sleep deprivation disrupts the ability to sustain attention, caused by a temporary failure of the right hemisphere's top-down (instruction-driven) processing to override the left hemisphere's bottom-up (stimulus-driven) processing.  相似文献   
855.
The relations for hand preference with craniofacial asymmetry and ear advantage, and between craniofacial asymmetry and ear advantage were investigated in young healthy subjects. Ear advantage was recorded as duration of hearing, craniofacial asymmetry by computerized tomography in 44 right-handed and 38 left-handed male and female high school students. Right-handers had a right ear advantage and a larger left craniofacial region, whereas left-handers had a left ear advantage and a larger right craniofacial region. These results are consistent with the speculation that hand preference may be related to craniofacial and consequently aural asymmetries.  相似文献   
856.
The concepts of health and disease are crucial in defining the aim and the limits of modern medicine. Accordingly it is important to understand them and their relationship. However, there appears to be a discrepancy between scholars in philosophy of medicine and health care professionals with regard to these concepts. This article investigates health care professionals’ concepts of health and disease and the relationship between them. In order to do so, four different models are described and analyzed: the ideal model, the holistic model, the medical model and the disjunctive model. The analysis reveals that each model has its pros and cons, and that health care professionals appear to apply more than one models. Furthermore, the models and the way health care professionals’ use them may be helpful for scholars in philosophy of medicine with regard to developing theories and communicating them to health care professionals.  相似文献   
857.
The present study examines changes in adolescents’ body image over a 10-year period. Both satisfaction with appearance in general, and satisfaction with different aspects of appearance (e.g., face, muscle tone, and weight) are considered. We analyzed data from two general population studies of 13–19-year-old Norwegians, “Young in Norway 1992” (N = 10,460, response rate = 97.0%) and “Young in Norway 2002” (N = 11,371, response rate = 92.3%). These studies used identical sampling procedures, data collection procedures, and measures of body image. The analyses showed a polarization in adolescents’ body image — concurrent with an increase in the proportion of adolescents with a very negative body image, there was an increase in the proportion of adolescents with a very positive body image. The greater proportion of adolescents with a very negative body image could partly be explained statistically by the increased body mass index (BMI) in the same period. Girls had a more problematic body image than boys, both in 1992 and in 2002. Whether the strength of this gender difference changed or not depended on the aspect of appearance considered.  相似文献   
858.
This study reports the effect of an affect-focused intervention program, the Affect School, on stress, psychological symptoms, cognitive functioning and neural activity. Fifty employees in social service and education, with high levels of chronic stress, were randomly divided into a treatment (N=27) and control (N=23) group. Complete sets of data were available in 20 participants in the treatment group and 17 in the control group. The Perceived Stress Questionnaire assessed stress and the Symptom Check List-90 psychological symptoms before and after treatment. Episodic-memory functioning under focused and divided attention conditions was also assessed. Prior and after the Affect School, seven participants in the treatment group were studied with functional magnetic resonance imaging (fMRI) during episodic memory processing. After the Affect School there was a reduction in stress and psychological symptoms for the treatment group but not in the control group. The controls showed a reduction in episodic memory functioning whereas the performance of the treatment group remained intact. The fMRI scanning indicated a qualitative change in the neural network subserving episodic memory. These preliminary results suggest that the Affect School is effective on individuals with high stress.  相似文献   
859.
This article examines the impact of the school-based smoking-prevention program "BE smokeFREE" on adolescent smoking. A national representative sample of 99 schools (195 classes, 4,441 students) was used when the intervention started in November 1994. Schools were allocated to one of four groups: a comparison group (A) and three intervention groups (B, C, and D). Group B received the most comprehensive intervention. A baseline (autumn 1994) and three follow-up data collections (1995, 1996, and 1997) were conducted. There were no significant differences in smoking habits among the four groups at baseline. The smoking habits in the group that was involved in the most comprehensive intervention (group B) changed more favourably than those of students in the comparison schools over the three follow-up data collections. At the third follow-up, the proportion of students smoking weekly or more in the comparison group was 29.2%, compared with 19.6% in the model intervention group. The two less comprehensive interventions (no teacher in-service courses in group C, and no involvement of parents in group D) appeared to be less effective than the model intervention. Multilevel multiple logistic regression analyses, comparing changes in smoking habits between students in group B with those among students in the comparison schools, confirm the conclusion that the comprehensive intervention was the most effective. This school-based intervention, based on a social influence approach, proved to be effective at reducing smoking rates among participants.  相似文献   
860.
Thirty-nine young adult participants performing the visual and tactile n-back working memory task were compared. In the visual task, letters were presented on a computer screen and in the tactile task, plastic letters embedded on a board were explored tactually. The amount of incorrect responses increased with increasing memory load in both tasks, but was significantly lower in the visual task. Subgrouping the participants with extreme performances into "skilled" and "poor" performers showed that the best performance was found among "skilled" visual performers, and the worst one among "poor" tactile performers. There was more interindividual variation among tactile than visual performance. We conclude that tactile working memory capacity, measured here by letter recognition and letter memory, is generally more limited and shows more variability than visual memory in normal sighted participants.  相似文献   
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