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851.
Stressful events activate the amygdala and a network of associated brain regions. Studies in both humans and rodents indicate that noradrenaline has a prominent role in this activation. Noradrenaline induces a hypervigilant state that helps to remember the event. This mnemonic effect is enhanced when the situation is so stressful that substantial amounts of corticosteroids are released and reach the amygdala. The combination of the two hormones leads to optimal strengthening of contacts and thus memory. Yet, rises in corticosteroid levels that are not precisely synchronized with noradrenaline release do not act synergistically but rather prevent or suppress the effect of noradrenaline. This dynamic interaction illustrates the adaptive and potentially protective capacity of corticosteroids regarding traumatic memories.  相似文献   
852.
This essay explicates and evaluates the roles that fetal metaphysics and moral status play in Rosalind Hursthouse’s abortion ethics. It is motivated by Hursthouse’s puzzling claim in her widely anthologized paper “Virtue Ethics and Abortion” that fetal moral status and (by implication) its underlying metaphysics are “in a way, fundamentally irrelevant” to her position. The essay clarifies the roles that fetal ontology and moral status do in fact play in her abortion ethics. To this end, it presents and then develops her fetal metaphysics of the potential and actual human being, which she merely adumbrates in her more extensive treatment of abortion ethics in her book Beginning Lives. The essay then evaluates her fetal ontology in light of relevant research on fetal neural and psychological development. It concludes that her implied view that the late-stage fetus is an actual human being is defensible. The essay then turns to the analysis of late-stage abortions in her paper and argues that it is importantly incomplete.  相似文献   
853.
Macular degeneration (MD) is the most common cause of visual impairment among older adults. It severely affects reading performance. People with MD have to rely on peripheral vision for reading. In this review, we considered several training programs that aim to improve peripheral reading, with a focus on eccentric viewing, oculomotor control, or perceptual learning. There was no strong support in favor of one particular training method for rehabilitation of reading in MD, but there is evidence that older individuals with MD can be trained to improve reading performance, even within limited time.  相似文献   
854.
This paper examines the ways the descendents of Portuguese-Canadian immigrants contemplate and formulate their identities. Through qualitative, open-ended interviews, the research demonstrates how these individuals contest ideas of ‘being Portuguese’ and ‘being Canadian’ within the frameworks of the Canadian multicultural policy. Refusing to be positioned outside the nation and Anglo/Francophone conformity, these individuals produce their own meanings of identity by working through their own personally identified multiethnic bodies to the national body politic, where some of them see their own selves as intrinsically ‘multicultural’ and contributors to the very definition of a Canadian identity. Challenging the tropes of the Canadian multicultural narrative, these descendents, thus, develop nuanced models of cultural citizenship, illustrating that national identities are formed and transformed in relation to representation. Through the process of narrative analysis, my endeavour of this article are twofold: on one hand, to illuminate the role of these individuals who, as active actors, are shaped by the social worlds they delve in and, on the other, to explicate how the roles played out by these actors can contribute to the construction of ‘a Canadian identity’.  相似文献   
855.
Language and music are closely related in our minds. Does musical expertise enhance the recognition of emotions in speech prosody? Forty highly trained musicians were compared with 40 musically untrained adults (controls) in the recognition of emotional prosody. For purposes of generalization, the participants were from two age groups, young (18-30 years) and middle adulthood (40-60 years). They were presented with short sentences expressing six emotions-anger, disgust, fear, happiness, sadness, surprise-and neutrality, by prosody alone. In each trial, they performed a forced-choice identification of the expressed emotion (reaction times, RTs, were collected) and an intensity judgment. General intelligence, cognitive control, and personality traits were also assessed. A robust effect of expertise was found: musicians were more accurate than controls, similarly across emotions and age groups. This effect cannot be attributed to socioeducational background, general cognitive or personality characteristics, because these did not differ between musicians and controls; perceived intensity and RTs were also similar in both groups. Furthermore, basic acoustic properties of the stimuli like fundamental frequency and duration were predictive of the participants' responses, and musicians and controls were similarly efficient in using them. Musical expertise was thus associated with cross-domain benefits to emotional prosody. These results indicate that emotional processing in music and in language engages shared resources.  相似文献   
856.
The authors examined whether, similar to collective agent behaviors in complex, biological systems (e.g., schools of fish and colonies of ants), performers in team sports displayed functional coordination tendencies, based on local interaction rules during performance. To investigate this issue, they used videogrammetry and digitizing procedures to observe interpersonal interactions in common 4 versus 2 + 2 subphases of the team sport of rugby union, involving 16 participants aged between 16 and 17 years of age. They observed pattern-forming dynamics in attacking subunits (n = 4 players) attempting to penetrate 2 defensive lines (n = 2 players in each). Data showed that within each attacking subunit, the 4 players displayed emergent functional grouping tendencies that differed between the 2 defensive lines. Results confirmed that grouping tendencies in attacking subunits of team games are sensitive to different task constraints, such as relative positioning to nearest defenders. It was concluded that running correlations were particularly useful for measuring the level of interpersonal coordination in functional grouping tendencies within attacking subunits.  相似文献   
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859.
This study investigated the Gestalt law of closure in baboons. Using a computer-controlled self-testing procedure, we trained baboons (Papio papio) to discriminate open versus closed shapes presented on a touch screen with a two-alternative forced choice procedure. Ten baboons (OPEN + group) were trained with the open shapes serving as the positive stimulus (S+), and nine others (CLOSE + group) were trained with the closed shape serving as S+. The OPEN + group obtained higher discrimination performance than the CLOSE + group (Exp 1), but its scores declined when new line segments were added to the stimuli (Exp 2) and after smoothing the end points of the open shapes (Exp 3). The CLOSE + group was less affected by the above manipulations of local stimulus dimension, but its performance was disrupted when the collinearity end points was reduced (Exp 3). Use of a visual search task revealed that the search for an open shape among closed distractors was less attention demanding in baboons than the search for a closed shape among open ones (Exp 4). It is concluded that (1) end lines rather than closeness per se are perceptual primitives for the open versus closed discrimination in baboons, and (2) the relative emphasis on local or configural cues when processing contour closure depends on experiential factors in baboons and is thus subject to interindividual variations.  相似文献   
860.
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