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141.
Mullen B 《Personality & social psychology bulletin》2004,30(2):250-260
An archival study examined the portrayal of ethnic immigrants to children as a function of the prevailing cognitive representation of those ethnic immigrant groups in ethnophaulisms. The complexity in ethnophaulisms (and, to a lesser degree, the valence in ethnophaulisms) predicted the portrayal of ethnic immigrant groups. Overall, ethnic immigrant groups characterized in terms of ethnophaulisms of low complexity were less frequently present in children's literature, children from these ethnic groups were described more in terms of physical appearance than in terms of personal traits, fictional child characters from those ethnic groups were portrayed with smaller heads and with lower verbal complexity, and the folksongs attributed to these groups had a more negative affective tone. The implications of these results for approaches to intergroup relations are considered. 相似文献
142.
When an object A moves toward an object B until they are adjacent, at which point A stops and B starts moving, we often see a collision--ie we see A as the cause of B's motion. The spatiotemporal parameters which mediate the perception of causality have been explored in many studies, but this work is seldom related to other aspects of perception. Here we report a novel illusion, wherein the perception of causality affects the perceived spatial relations among two objects involved in a collision event: observers systematically underestimate the amount of overlap between two items in an event which is seen as a causal collision. This occurs even when the causal nature of the event is induced by a surrounding context, such that estimates of the amount of overlap in the very same event are much improved when the event is displayed in isolation, without a 'causal' interpretation. This illusion implies that the perception of causality does not proceed completely independently of other visual processes, but can affect the perception of other spatial properties. 相似文献
143.
Omega (n)-3 and n-6 fatty acids are important membrane components of neurons and immune cells, and related to psychiatric and inflammatory diseases. Increased ratio of n-6/n-3 in the blood has been reported in depressed patients and in students following stress exposure. The n-3 fatty acid, eicosapentaenoic acid (ethyl-EPA) suppresses inflammation and has antidepressant properties. Interleukin (IL)-1beta can stimulate corticosterone secretion, induce anxiety and stress-like behavior and inflammatory responses. This study was to evaluate the effect of diets enriched with coconut oil, ethyl-EPA and soybean oil on central IL-1beta induced stress and anxiety-like behavior, induced changes in the concentration of prostaglandin (PG) E2 and corticosterone and the release of IL-10. Groups of rats were fed with either 5% coconut oil (as control diet), 0.2% EPA with 4.8% coconut oil or 1% EPA with 4% coconut oil and 5% soybean oil for 7 weeks. The central administration of IL-1beta induced sickness, stress and anxiety-like behavior as indicated by a reduction in body weight, decreased time spent, and the number of entries, into the open arms of the elevated plus maze and decreased exploration and entry into the central zone of the "open field" apparatus. IL-1beta also increased PGE2 and corticosterone concentrations and decreased the release of IL-10 from leucocytes. Food enriched with ethyl-EPA but not soybean oil, significantly attenuated most of these changes. These results demonstrate that ethyl-EPA has anti-inflammatory, anti-stress and anti-anxiety effects in rats. 相似文献
144.
145.
Schrag B Freeberg T Anestidou L 《Science and engineering ethics》2004,10(4):717-20; discussion 721-34
This case involves invasive research on captive wild populations of birds to study aggressive animal behavior. The case and associated commentaries raise and examine fundamental issues, whether and under what conditions, such research is ethically justified when the research has no expected, direct application to the human species; the moral status of animals and how one balances concern for the animal's interests against the value of gains in scientific knowledge. They also emphasize the issue of the importance of a thorough literature search to ensure appropriate research design and experimental design to minimize animal suffering. It raises the issue of circumstances in which such research should be modified or terminated. 相似文献
146.
Beyond perceiving patterns of motion in simple dynamic displays, we can also perceive higher level properties, such as causality, as when we see one object collide with another object. Although causality is a seemingly high-level property, its perception--like the perception of faces or speech--often appears to be automatic, irresistible, and driven by highly constrained and stimulus-driven rules. Here, in an exploration of such rules, we demonstrate that perceptual grouping and attention can influence the both perception of causality in ambiguous displays. We first report several types of grouping effects, based on connectedness, proximity, and common motion. We further suggest that such grouping effects are mediated by the allocation of attention, and we directly demonstrate that causal perception can be strengthened or attenuated on the basis of where observers are attending, independent of fixation. Like Michotte, we find that the perception of causality is mediated by strict visual rules. Beyond Michotte, we find that these rules operate not only over discrete objects, but also over perceptual groups, constrained by the allocation of attention. 相似文献
147.
Levine B 《Brain and cognition》2004,55(1):54-68
Autobiographical remembering reflects an advanced state of consciousness that mediates awareness of the self as continuous across time. In naturalistic autobiographical memory, self-aware recollection of temporally and spatially specific episodes and generic factual information (both public and personal) operate in tandem. Evidence from both laboratory and real-life studies, however, suggests that these two processes can be dissociated. This paper reviews aging, lesion, and functional neuroimaging research on the anatomical substrates of autobiographical memory processes using a new measure, the Autobiographical Interview, and prospective collection of autobiographical material. Results indicate that autobiographical recollection is mediated by a distributed fronto-temporo-parietal system, with the anteromedial prefrontal cortex positioned to integrate sensory information with self-specific information. The emergence of autobiographical recollection at around age four coincides with the timing of prefrontal regressive cortical and progressive white matter changes that may support the development of this high-level capacity. 相似文献
148.
149.
Coherent visual experience requires not only segmenting incoming visual input into a structured scene of objects, but also binding discrete views of objects into dynamic representations that persist across time and motion. However, surprisingly little work has explored the principles that guide the construction and maintenance of such persisting object representations. What causes a part of the visual field to be treated as the same object over time? In the cognitive development literature, a key principle of object persistence is cohesion: An object must always maintain a single bounded contour. Here we demonstrate for the first time that mechanisms of adult midlevel vision are affected by cohesion violations. Using the object-file framework, we tested whether object-specific preview benefits-a hallmark of persisting object representations-are obtained for dynamic objects that split into two during their motion. We found that these preview benefits do not fully persist through such cohesion violations without incurring significant performance costs. These results illustrate how cohesion is employed as a constraint that guides the maintenance of object representations in adult midlevel vision. 相似文献
150.
Following F. Zaal and R. J. Bootsma (1995), the authors studied whether the decelerative phase of a reaching movement could be modeled as a constant tau-dot strategy resulting in a soft collision with the object. Specifically, they investigated whether that strategy is sustained over different viewing conditions. Participants (N = 11) were required to reach for 15- and 50-mm objects at 2 different distances under 3 conditions in which visual availability of the immediate environment and of the reaching hand were varied. Tau-dot estimates and goodness-of-fit were highly similar across the 3 conditions. Only within-participant variability of tau-dot estimates was increased when environmental cues were removed. That finding suggests that the motor system uses a tau-dot strategy involving the intermodal (i.e., visual, proprioceptive, or both) specification of information to regulate the decelerative phase of reaching under restricted viewing conditions. The authors provide recommendations for improving the derivation of tau;(x) estimates and stress the need for further research on how time-to-contact information is used in the regulation of the dynamics of actions such as reaching. 相似文献