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841.
Ghrelin (Grh) is an endogenous ligand for the growth hormone secretagogue receptor. Although Ghr stimulates feeding in rats, it inhibits feeding in neonatal chicks. However, little is known about other central behavioral effects of Ghr. Therefore, we investigated the Ghr effects, injected intracerebroventricularly, on anxiety and memory retention of neonatal chicks in an Open Field test and in a one-trial passive avoidance task, respectively. In the Open Field test, the administration of Ghr in a dose-dependent manner increased the latency to ambulate but decreased ambulation activity, indicating an anxiogenic effect. Furthermore, chicks trained on a passive avoidance task and injected with a dose of 30 pmol of Ghr immediately after training showed an impairment of memory retention. However, there were no significant effects on the number of pecks during the pretraining, training, retention and discrimination. In addition, different doses of Ghr produced an inhibition in food intake at different times after injection. Our results indicate that Ghr induces anxiogenesis in chicks. Moreover, we have shown for the first time that Ghr can decrease memory retention in a non-mammalian species, suggesting that Ghr may play an important role in the processes of memory retention in birds.  相似文献   
842.
The aim of the present study was to identify relevant variables associated with Quality of Life (QoL) in older adults. Older adults, up to 60 years old, were interviewed. Subjects were recruited through convenience sampling. 339 paticipants, who were stratified by gender, age, and subjective perception of health and illness, answered questions on sociodemographic issues, QoL (WHOQOL-100) and depressive symptomathology (Beck Depression Inventory—BDI). The multiple linear regression analysis showed associations of overall perception of QoL with depression levels, subjective perception of health status and gender. The individual analysis of each domain concluded that depression levels are correlated to all QoL domains, while health status was associated with physical, psychological, independence level and social relationship domains. Other variables were also assessed. The assessment of older adults concerning their QoL perceptions is associated with gender, age, marital status, social class, literacy rate, perception of health, and more substantially associated with depressive symptoms levels. Nevertheless, some limitations of this study and further ones are suggested.  相似文献   
843.
Previous Chinese research on adolescent life stress adopted life event scales that were directly translated from Western measures. To address the methodological and cultural issues overlooked by the import approach, the present research aimed at constructing a life event scale for Hong Kong adolescents. Study 1 was conducted to congregate items for the Chinese Adolescent Life Event Scale (CALES). The CALES contains 44 items derived from 618 Hong Kong adolescents. Study 2 revealed adequate test–retest reliability and criterion-related validity for the CALES. Moreover, the CALES yielded stronger relationships with depression than did the translated life event measures. Results suggest that the CALES is appropriate for assessing life events for Hong Kong adolescents. Both unique features of the CALES and life events found only in the translated measures are examined. Implications for Chinese research on life stress are discussed.  相似文献   
844.
Even though France has experienced increasing and inevitable feminization in its immigrant population since 1974, research has tended to ignore the role of immigrant women, especially Muslim women, in the migration process. Public attention has been diverted by concern over such relatively marginal issues as the headscarf affair, and insufficient attention has been paid to the important role Muslim women play in France, especially those coming from Algeria. These women function as cultural mediators between the traditional culture of the sending country and the modern one of the host country. They see themselves as both tradition-bearers and integration proponents. The demands of immigration have given rise to the growth and development of different leaders, among them cultural mediators seeking a bridge between Islam and modernity, economic mediators seeking to establish women in the media and as entrepreneurs, and political mediators who seek access to power at the local level for the immigrants. These new mediators will eventually shape a new generation of female actors very far from the traditional countries of origin, although for the time being they still suffer from the inequality of rights for women and chances in their overall social life.  相似文献   
845.
Higher-order evidence can make an agent doubt the reliability of her reasoning. When this happens, it seems rational for the agent to adopt a cautious attitude towards her original conclusion, even in cases where the higher-order evidence is misleading and the agent's original reasons were actually perfectly good. One may think that recoiling to a cautious attitude in the face of misleading self-doubt involves a failure to properly respond to one's reasons. My aim is to show that this is not so. My proposal is that (misleading) higher-order evidence can undermine the agent's possession of her first-order reasons, constituting what I call a dispossessing defeater. After acquiring the higher-order evidence, the agent is no longer in a position to rely competently on the relevant first-order considerations as reasons for her original conclusion, so that such reasons stop being available to her (even if they remain as strong as in the absence of the higher-order evidence). In this way, an agent with misleading higher-order evidence can adopt a cautious stance towards her original conclusion, while properly responding to the set of reasons that she possesses–a set that is reduced due to the acquisition of higher-order dispossessing defeaters.  相似文献   
846.
In this paper, we attempt to make a distinction between egocentrism and allocentrism in social cognition, based on the distinction that is made in visuo-spatial perception. We propose that it makes a difference to mentalizing whether the other person can be understood using an egocentric ("you") or an allocentric ("he/she/they") stance. Within an egocentric stance, the other person is represented in relation to the self. By contrast, within an allocentric stance, the existence or mental state of the other person needs to be represented as independent from the self. We suggest here that people with Asperger syndrome suffer from a disconnection between a strong na?ve egocentric stance and a highly abstract allocentric stance. We argue that the currently used distinction between first-person and third-person perspective-taking is orthogonal to the distinction between an egocentric and an allocentric stance and therefore cannot serve as a critical test of allocentrism.  相似文献   
847.
Young children are assumed to be inefficient inhibitors in a number of cognitive tasks. In two experiments, we examined whether such deficits extend to children's episodic recall. We used two inhibition paradigms: retrieval-induced forgetting, the detrimental effect of retrieval practice with a subset of learned items on recall of the unpracticed items, and part-list cuing, the detrimental effect of the presentation of a subset of learned items on recall of the remaining items. In both experiments, the inhibitory effects were compared across three age groups: first or second graders, fourth graders, and young adults. The two children groups showed the same amounts of retrieval-induced forgetting and part-list cuing as the adult group, pointing to intact retrieval inhibition in young children's episodic recall. These results parallel very recent results on older adults' episodic recall, suggesting that both retrieval-induced forgetting and part-list cuing develop early in life and remain intact for the greater part of the lifespan.  相似文献   
848.
In this article, we examine how being assigned the role of leader affects behaviour in resource sharing tasks. Previous research has shown that group members anchor their decision on the equal division rule prescribing that resources should be distributed equally. Following notions of equity theory and the literature on role schemas, we expected that adherence to the equal division rule would be moderated by role assignment. In particular, we expected leaders to take more than followers from a common resource and that this effect would be explained in terms of feelings of entitlement. The results of two experimental studies corroborate this reasoning. Study 1 demonstrated that leaders took more than followers and that leaders deviated more strongly from the equal division rule. In Study 2, it was found that legitimate leaders took more from the resource and deviated more strongly from the equal division rule than non‐legitimate leaders. Additional analyses suggest that the leaders' tendency to make higher allocations to the self can be explained by feelings of entitlement. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
849.
Dogs can use a variety of experimenter-given cues such as pointing, head direction, and eye direction to locate food hidden under one of several containers. Some authors have proposed that this is a result of the domestication process. In this study we tested four captive fur seals in a two alternative object choice task in which subjects had to use one of the following experimenter-given cues to locate the food: (1) the experimenter pointed and gazed at one of the objects, (2) the experimenter pointed at only one of the objects, (3) the experimenter gazed at only one of the objects, (4) the experimenter glanced at only one of the objects, (5) the experimenter pointed and gazed at one of the objects but was sitting closer to one object than to the other, (6) the experimenter pointed only with the index finger at one of the objects, (7) the experimenter presented a replica of one of the objects. The fur seals were able to use cues which involved a fully exposed arm or a head direction, but failed to use glance only, the index finger pointing and the object replica cues. The results showed that a domestication process was not necessary to develop receptive skills to cues given by an experimenter. Instead, we hypothesize that close interactions with humans prior to testing enabled fur seals to use some gestural cues without formal training. We also analyzed the behavior of the seals depending on the level of difficulty of the task. Behavioral signs of hesitation increased with task difficulty. This suggests that the fur seals were sensitive to task difficulty.  相似文献   
850.
The male-offspring biased visual kin recognition in chimpanzees (Pan troglodytes) reported by L. A. Parr and F. B. M. de Waal (1999) was replicated with human (Homo sapiens) participants and a principal components analysis (PCA) of pixel maps of the chimpanzee face photos. With the same original materials and methods, both humans and the PCA produced the same asymmetry in kin recognition as found with the chimpanzees. The PCA suggested that the asymmetry was a function of differences in the distribution of global characteristics associated with the framing of the faces in the son and daughter test sets. Eliminating potential framing biases, either by cropping the photos tightly to the faces or by rebalancing the recognition foils, eliminated the asymmetry but not human participants' ability to recognize chimpanzee kin.  相似文献   
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