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231.
Reunion behavior following stressful separations from caregivers is often considered the single most sensitive clue to infant attachment patterns. Extending these ideas to middle childhood/early adolescence, we examined participants' neural responses to reunion with peers who had previously excluded them. We recorded event‐related potentials among nineteen 11‐ to 15‐year‐old youth previously classified on attachment interviews (11 secure and 8 insecure‐dismissing) while they played a virtual ball‐toss game (Cyberball) with peers that involved fair play, exclusion and reunion phases. Compared to secure participants, dismissing participants displayed a greater increment in the N2 during reunion relative to fair play, a neural marker commonly linked to expectancy violation. These data suggest a greater tendency toward continued expectations of rejection among dismissing children, even after cessation of social exclusion. In turn, the link between self‐reported ostracism distress and neural signs of negative expectancy at reunion was moderated by attachment, such that self‐reports were discordant with the neural index of expectancy violation for dismissing, but not for secure children. A video abstract of this article can be viewed at http://www.youtube.com/watch?v=qzoRel5c-4s .  相似文献   
232.
We examined cross-sectional differences and longitudinal changes in episodic memory performance related to impending death among a group of very old people, aged 90–101 years. Participants were assessed at 3 measurement points across a 6-year interval. Three groups were identified: those who survived the entire follow-up period (n =40), those who died before the first follow-up (n =44), and those who died after the first follow-up (n =14). Participants completed a battery of episodic memory tasks consisting of face recognition, word recognition, word recall, and object recall with selective reminding. Those who survived performed better than those who were going to die in object recall at baseline. A Cox regression analysis, controlling age, revealed that object recall performance was significantly related to subsequent mortality status. Longitudinal analyses demonstrated significant 3-year decline for both face recognition and object recall, but no evidence of differential decline as a function of mortality group. Thus, longitudinal changes in memory preceding death were not as pronounced as the corresponding cross-sectional differences in this very old sample. In general, the results suggest that mortality-related memory deficits are present in extreme old age, although these deficits are relatively small and task-specific.  相似文献   
233.
We examined the relationship between type 2 diabetes mellitus and cognitive function in a population-based sample of very old people. The sample comprised 338 persons, aged 80-93 years (mean age 83.5 years), of whom 70 persons had type 2 diabetes mellitus. Measures of cognitive functioning included tests of perceptual speed, visuo-spatial ability, inductive reasoning, short-term memory, semantic memory, episodic memory, and the Mini-Mental State Examination. Regression analyses showed that type 2 diabetes mellitus duration was related to test performance across all cognitive domains, with the exception of short-term memory, such that longer duration was associated with lower test performance. When cases with dementia were excluded from the sample, further analyses showed that diabetes duration was not associated with cognitive test performance. This indicates that diabetes is not related to lower cognitive function in the general population of non-demented old people. Diabetes, however, increases the risk for cerebrovascular incidents, like stroke, that may contribute to vascular dementia.  相似文献   
234.
This experiment sought further support for the view that early stage Alzheimer's disease (AD) disrupts cognitive structures that cast experience into a temporal framework. Forty participants, evenly divided between normal elderly (NE) and persons diagnosed with mild AD, viewed 19 lists of 14 pictures each. Following the presentation of each list participants were asked to identify the most recently experienced picture (target) from 3 pictures. A second stimulus was a picture never previously seen; the third picture was a distracting item that had appeared in the list on either one or three occasions. The results show that whereas choice accuracy of the NE group remained largely unimpaired regardless of the delay between the target and the judgment task or the frequency of the distractor, the AD participants exhibited large and profound deficits in temporal judgments, especially when distractor frequency was greater than the more recent event. In effect, the AD group relied on how often an event occurred rather than the time of its occurrence. This finding is consistent with previous research that found AD patients deficient in forming a temporal representation of their experience.  相似文献   
235.
Our aim in this paper is to bring attention to the applied value of collaborative memory research in aging. At this time, much collaborative memory research focuses on the negative effects of collaboration in younger adults, and is primarily basic in nature. Here, we highlight the positive effects of collaboration that have received less attention, with a particular emphasis on the applied value of these effects in older adults. We first review studies to show that recalling in a group improves later individual recall and reduces memory errors in older adults. We then outline a four-step approach towards bridging laboratory and applied collaborative memory research, which involves: (1) complementing traditional paradigms with more ecologically valid paradigms, (2) evaluating these paradigms in applied settings, (3) adapting these paradigms for use with cognitively intact and cognitively impaired populations, and (4) modifying these paradigms to examine the neural systems that operate during collaborative recall.  相似文献   
236.
Development as a dynamic system   总被引:1,自引:0,他引:1  
Development is about creating something more from something less, for example, a walking and talking toddler from a helpless infant. One current theoretical framework views the developmental process as a change within a complex dynamic system. Development is seen as the emergent product of many decentralized and local interactions that occur in real time. We examine how studying the multicausality of real-time processes could be the key to understanding change over developmental time. We specifically consider recent research and theory on perseverative reaching by infants as a case study that demonstrates this approach.  相似文献   
237.
Evolution, Discovery, and Interpretations of Arthropod Mushroom Bodies   总被引:13,自引:0,他引:13       下载免费PDF全文
Mushroom bodies are prominent neuropils found in annelids and in all arthropod groups except crustaceans. First explicitly identified in 1850, the mushroom bodies differ in size and complexity between taxa, as well as between different castes of a single species of social insect. These differences led some early biologists to suggest that the mushroom bodies endow an arthropod with intelligence or the ability to execute voluntary actions, as opposed to innate behaviors. Recent physiological studies and mutant analyses have led to divergent interpretations. One interpretation is that the mushroom bodies conditionally relay to higher protocerebral centers information about sensory stimuli and the context in which they occur. Another interpretation is that they play a central role in learning and memory. Anatomical studies suggest that arthropod mushroom bodies are predominately associated with olfactory pathways except in phylogenetically basal insects. The prominent olfactory input to the mushroom body calyces in more recent insect orders is an acquired character. An overview of the history of research on the mushroom bodies, as well as comparative and evolutionary considerations, provides a conceptual framework for discussing the roles of these neuropils.  相似文献   
238.
239.
Research on HIV/AIDS interventions indicates that many heterosexual women implement the construct of trust when deciding if preventive measures are necessary. The personal construct model evaluated in this experiment proposes that young women's choice to resist changing from a trust to a nontrust position can be understood in terms of the relationship between their constructs and the hierarchical organization of their construct subsystems. Findings suggest that women with well-defined networks of implications on their nonpreferred pole of the trust/mistrust construct resist HIV-preventive messages that require them to mistrust their partner because the proposed change will involve successive use of subordinate constructs that are incompatible with each other.  相似文献   
240.
This article is concerned with the devaluation of the work of public intellectuals within the academic community. The principal reason given for this devaluation is that the work of the public intellectual does not have intellectual integrity as independent thought and original scholarship. I develop three models of public intellectual work: the permanent–critic model, the popularizer model, and the public–theorist model. I then consider each model in relation to the concern with intellectual integrity and conclude that both independent thought and original scholarship are possible within work that is engaged with nonacademic publics.  相似文献   
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