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1.
Following a long, full bleach, rod dark-adaptation curves from two normal trichromats were obtained with test fields of various size, exposure time and retinal eccentricity. The results show that there is a substantial region of threshold recovery with an approximately constant, linear slope of about 0.27 log per minute of dark-adaptation, which is independent of the test variables. It is suggested that the increase in sensitivity during this constant, linear slope is completely determined by changes in the concentration of bleached rhodopsin. The relationship between change of relative threshold (T) and fraction of bleached rhodopsin ( B ) is given by T=B 3,7. This exponential law is well described by the displacement of the equilibrium between the active and inactive states of an allosteric enzyme built as a tetrarner.  相似文献   

2.
The ordinary long-term rod and cone dark-adaptation curves have generally been assumed to follow a single exponential rate of recovery. However, in two previous papers on rod dark-adaptation (Stabell et al., 1986a, b), the recovery curve was found to consist of three different sections. The results of the present paper show the same type of recovery function with three different sections for the long-term dark-adaptation curve of the long-wave cone system. During the major, middle section log cone threshold, like log rod threshold, is linearly related to the logarithm of the concentration of bleached photopigment. Presupposing that the bleached cone photopigment acts as a ligand, the change in threshold level obtained during the middle section of the dark-adaptation curve is well described by the change in activity rate of an allosteric, postively cooperative enzyme built as a dimer.  相似文献   

3.
Recent evidence strongly suggests that the relationship between threshold elevation ( T ) and fraction of bleached rhodopsin ( B ), obtained during a major, middle period of long-term rod dark adaptation in man, is well described by a power function, i. e., T = k · Bn , where k is a multiplicative constant and n is the exponent. Due primarily to the low reliability of measurements of rhodopsin regeneration, however, the exponent n of the power function cannot, at present, be given an exact value. Available information indicates that the value of the exponent ranges between 2.4 and 4. Implications of this uncertainty are discussed within the framework of the allosteric, tetrameric model of rod dark adaptation. It is concluded that this model in its simplest form may only offer a first approximation of the real system implicated in the process.  相似文献   

4.
R L Calabrese  H Schumer 《Adolescence》1986,21(83):675-687
This research evaluated the effects of involvement of adolescents in community service activities on levels of alienation. It was proposed that alienation could be reduced through the implementation of a model which utilized community service activities to facilitate adolescent access to adult society, development of responsibility, collaborative and cooperative work, and control over planning and outcomes. It is suggested that adolescent involvement in service activities can produce positive benefits, among which are reduced levels of alienation, improved school behavior, improved grade point average, and acceptance by the adult community. These findings also suggest that females respond more positively to school when allowed to problem-solve collectively and collaboratively.  相似文献   

5.
Two recent papers by Kuczaj et al. (Anim Cognit 18:543–550, 2015) and Eskelinen et al. (Anim Cognit 19:789–797, 2016) claim to have demonstrated that (i) bottlenose dolphins (Tursiops truncatus) cooperated to solve a novel task and (ii) vocal signals were important for coordinating these cooperative efforts. Although it is likely that bottlenose dolphins may share communicative signals in order to achieve a common goal, we suggest that this has not been demonstrated in the aforementioned studies. Here, we discuss the two main problems that preclude any definitive conclusions being drawn on cooperative task success and vocal communication from these studies. The first lies in the experimental design. The ‘cooperative task’, involving an apparatus that requires two dolphins to pull in opposite directions in order to achieve a food reward, is not conducive to cooperation, but could instead reflect a competitive ‘tug-of-war’. It is therefore of questionable use in distinguishing competitive from cooperative interactions. Second, the suggestion that the occurrence of burst-pulsed signals in this task was indicative of cooperation is disputable, as (i) this study could not determine which dolphins were actually producing the signals and (ii) this sound type is more commonly associated with aggressive signalling in dolphins. We commend the authors for investigating this exciting and topical area in animal communication and cognition, but the question of whether dolphins cooperate and communicate to solve a cooperative task remains as yet unanswered.  相似文献   

6.
Stiles and Crawford proposed that a retinal region bleached by preexposure to intense light behaves as if it were illuminated by some steady veiling or background luminance. We test this notion by comparing the afterimage of a bleaching light with a steady (and retinally stabilized) light of adjustable intensity, in the manner of Barlow and Sparrock. With their matching procedure, and also with a new procedure, we find as they did that during the rod phase of recovery the afterimage does look like a stabilized field of an intensity which, presented as a background, brings visual sensitivity to the same level. It is as if the two conditions produce equal signals at some stage of the visual pathway. Liked Barlow and Sparrock we observe a rod-cone break in the afterimage matches. However, we argue that the appearance of the rod-cone break presents a paradox and we show a way to resolve it.  相似文献   

7.
动态两难对策中信息反馈方式对合作行为的影响   总被引:4,自引:0,他引:4  
何贵兵 《心理科学》2004,27(4):876-880
本研究着重探讨了多人动态对策情景中信息反馈方式和群体认同度对合作行为变化的影响。结果表明,集体反馈比个人反馈更能促进被试的合作行为,而群体认同度对合作行为的影响不显著;在集体反馈条件下,合作行为在各轮次问的随机波动较大,但在三个决策阶段问较为稳定;个人反馈条件下,合作行为在各轮次问的随机波动较小,但在三阶段问呈现出不对称的“U”型变化趋势。研究认为,建立在反馈信息基础上的决策学习使合作行为的动态变化具有策略性和适应性。  相似文献   

8.
When do people cooperate? The neuroeconomics of prosocial decision making   总被引:1,自引:0,他引:1  
Understanding the roots of prosocial behavior is an interdisciplinary research endeavor that has generated an abundance of empirical data across many disciplines. This review integrates research findings from different fields into a novel theoretical framework that can account for when prosocial behavior is likely to occur. Specifically, we propose that the motivation to cooperate (or not), generated by the reward system in the brain (extending from the striatum to the ventromedial prefrontal cortex), is modulated by two neural networks: a cognitive control system (centered on the lateral prefrontal cortex) that processes extrinsic cooperative incentives, and/or a social cognition system (including the temporo-parietal junction, the medial prefrontal cortex and the amygdala) that processes trust and/or threat signals. The independent modulatory influence of incentives and trust on the decision to cooperate is substantiated by a growing body of neuroimaging data and reconciles the apparent paradox between economic versus social rationality in the literature, suggesting that we are in fact wired for both. Furthermore, the theoretical framework can account for substantial behavioral heterogeneity in prosocial behavior. Based on the existing data, we postulate that self-regarding individuals (who are more likely to adopt an economically rational strategy) are more responsive to extrinsic cooperative incentives and therefore rely relatively more on cognitive control to make (un)cooperative decisions, whereas other-regarding individuals (who are more likely to adopt a socially rational strategy) are more sensitive to trust signals to avoid betrayal and recruit relatively more brain activity in the social cognition system. Several additional hypotheses with respect to the neural roots of social preferences are derived from the model and suggested for future research.  相似文献   

9.
刘耀中  窦凯 《心理科学》2015,(3):643-650
社会困境中的合作行为是通过抑制个体利益最大化的诱惑从而满足集体利益最大化的过程。研究采用囚徒困境游戏范式考察个体的合作行为,通过设置决策顺序操控人际控制感的高低,利用ERPs技术探讨了人际控制感影响合作行为的神经机制。行为结果发现:高人际控制感条件下个体做出合作行为的频率显著高于低人际控制感。ERPs结果发现:个体在高人际控制感条件下博弈时顶枕区所诱发的P2波幅更小,且右侧额区所诱发的N2波幅也更小。这表明被试在高人际控制感条件下感知到的不确定性更小,冲突控制水平更高,从而更能抑制利己诱惑,表现出更多的合作行为。  相似文献   

10.
用中国人个性量表(CPAI)预测国有企业中高层管理者的绩效   总被引:3,自引:0,他引:3  
本研究用中国人个性量表 (CPAI)测量了某国有企业的 3 8名中高级管理人员 ,并获得了他们最近的上司评定绩效资料。相关分析表明 ,CPAI的和谐维度与工作能力和工作态度的多个指标有正相关 ,CPAI的领导维度与沟通能力有正相关。与假设相反 ,老实 -圆滑和务实与沟通能力有负相关 ;越外控的员工 ,其合作态度的评价越高。这可能表明了国企管理的某些特点对人格—绩效关系的影响。本研究揭示了一些被西方心理学家忽视的人格维度对于中国企业人力资源管理的重要意义。  相似文献   

11.
Previous research highlighting the role sexual selection may play in the evolution of human cooperation has yet to distinguish what qualities such behaviours actually signal. The aim here was to examine whether female preferences for male cooperative behaviours are because they signal genetic or indirect phenotypic quality. This was possible by taking into account female participants' stage of menstrual cycle, as much research has shown that females at the most fertile stage show greater preferences specifically for signals of genetic quality than any other stage, particularly for short-term relationships. Therefore, different examples of cooperation (personality, costly signals, heroism) and the mate preferences for altruistic traits self-report scale were used across a series of four experiments to examine females' attitudes towards cooperation in potential mates for different relationship lengths at different stages of the menstrual cycle. The results here consistently show that female fertility had no effect on perceptions of cooperative behaviour, and that such traits were considered more important for long-term relationships. Therefore, this provides strong evidence that cooperative behaviour is important in mate choice as predominantly a signal of phenotypic rather than genetic quality.  相似文献   

12.
崔丽莹 《心理科学》2011,34(3):613-618
目的:旨在揭示中小学儿童的人际信任、成就动机水平及其与合作倾向之间的关系。方法:运用马基量表、人际信任量表、成就动机量表和合作倾向评价表对553名3-8年级学生进行测查。结果:1,初中男女生在人际信任水平上出现明显分化。2,男生追求成功的动机和避免失败的动机随年龄增长出现下降趋势,女生追求成功的动机下降,避免失败的动机上升。3,追求成功的动机与合作倾向有显著正相关。结论:与人际信任水平相比,成就动机在儿童合作倾向的评价中发挥了更大的作用。  相似文献   

13.
A concerted move towards the use of experimental analyses is proposed. It is suggested that our understanding of agoraphobia can best be advanced by taking this step. The argument in support of such a move is illustrated and developed in respect of the role of safety signals in maintaining and influencing agoraphobic behaviour. A detailed analysis is given of the factors postulated to determine the strength of safety signals, and the complex inter-relations between fear and safety are examined.  相似文献   

14.
供应链伙伴间的信任、承诺对合作绩效的影响   总被引:18,自引:0,他引:18  
潘文安  张红 《心理科学》2006,29(6):1502-1506
本文通过问卷调查的方式探讨供应链伙伴间的信任、关系承诺对合作绩效的影响。研究结果显示组织信任、个人信任与合作绩效存在正相关关系,组织信任通过关系承诺对合作绩效的间接影响明显高于其直接影响,个人信任通过关系承诺对合作绩效的间接影响明显不及其直接影响。  相似文献   

15.
This study extends research on the adaptive aspects of dispositional optimism to romantic relationships. We hypothesized that optimism would be positively linked to cooperative problem solving in romantic relationships, given previous research indicating that optimists are likely to use approach coping strategies. Results indicated that optimism was linked to satisfying and happy romantic relationships, and a substantial portion of this association was mediated by reports of cooperative problem solving. Moreover, optimism predicted relative increases in relationship satisfaction over a 2-year interval. All told, these results suggest that optimism may serve as an enduring resource for romantic unions.  相似文献   

16.
We provide evidence that the capacity of young children to engage in social interaction exceeds that suggested by Piaget (1926). Rather than being collective monologues, the conversations between the subjects of this study (twin boys) were dialogues: the children attended to one another's utterances and provided relevant responses. This was observed for conversations which were referentially based as well as for sound play exchanges. This is not to say that the children experienced no difficulty in sustaining cooperative discourse. It could take a speaker several turns to secure the attention of the coconversationalist and establish a discourse topic.  相似文献   

17.
Relationships of mother and nonmaternal caregiver with 33 three‐year‐old kibbutz toddlers were investigated. Attunement and intrusiveness of these caregivers in their contact with children were determined by analysis of discrete child–adult interactions rather than by a global assessment of their relationships. The validity of these adult attunement scores was examined first by comparison of the attunement and intrusiveness scores of mother and of caregiver, and second by determining their association with independent scores of child availability to each of these caregiving adults. Results tended to support the validity of the present measures of adult attunement to the child. They indicated that in cases of disagreement mothers were more attuned than nonmaternal caregivers to the signals of the child, and the level of adult attuned agreement to the child was positively associated with cooperative attempts of children to involve caregivers in their activities © 2000 Michigan Association for Infant Mental Health.  相似文献   

18.
In speeded response tasks with redundant signals, parallel processing of the redundant signals is generally tested using the so-called race inequality. The race inequality states that the distribution of fast responses for a redundant stimulus never exceeds the summed distributions of fast responses for the single stimuli. It has been pointed out that fast guesses (e.g. anticipatory responses) interfere with this test, and a correction procedure (‘kill-the-twin’ procedure) has been suggested. In this note we formally derive this procedure and extend it to the case in which redundant stimuli are presented with onset asynchrony. We demonstrate how the kill-the-twin procedure is used in a statistical test of the race model prediction.  相似文献   

19.
The present study investigated whether cooperative goals mediate the relationship between similarity in gender and self‐esteem and social support and relationship quality in ongoing peer dyads. Based on data collected from 209 student dyads, the findings largely support the mediating role of cooperative goals. However, the study found that gender similarity was positively related while self‐esteem similarity was negatively related to cooperative goals and relationship quality of peer dyad members.  相似文献   

20.
According to Evolutionary Game Theory, multiple exchanges with partners are necessary to foster cooperation. Multiple exchanges with partners tend to enhance the good experience of the partners and the predictability of their behaviour and should therefore increase cooperativeness. This study explored whether social embeddedness, or the preference for close and stable social relationships, a variable which tends to increase multiple exchanges, is associated with more cooperative attitudes; and whether social embeddedness increases cooperative behavior towards unknown partners in a game situation. The first study, with 169 undergraduates, indicated that social embeddedness (preference for close and durable social relations) was negatively associated with opportunistic attitudes. The second study had a sample of 60 undergraduates playing a Trust Game with unknown partners and showed that self-reported social embeddedness was positively correlated with scores for cooperative economic behavior towards the partners. These results highlight the relationships of social embeddedness with cooperative attitudes and behaviour.  相似文献   

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