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961.
We have assessed the optimal cone contrast sensitivity across eccentricity in human vision of the two cone-opponent mechanisms [L/M or red-green, and S/(L + M) or blue-yellow] and the luminance mechanism. We have used a novel stimulus, termed a 'sinring', that is a radially modulated sine-wave arc, Gaussian enveloped in both angular and radial directions. This stimulus overcomes the problem inherent in Gabor stimuli of confounding stimulus spatial frequency, size, and eccentricity and so allows contrast sensitivity to be tracked accurately into the periphery. Our results show that L/M cone opponency declines steeply across the human periphery and becomes behaviourally absent by 25-30 deg (in the nasal field). This result suggests that any L/M cone-opponent neurons found in primate peripheral retina beyond this limit are unlikely to be significant for colour contrast detection measured behaviourally. 相似文献
962.
Jescheniak JD Hantsch A Schriefers H 《Journal of experimental psychology. Learning, memory, and cognition》2005,31(5):905-920
Speakers are regularly confronted with the choice among lexical alternatives when referring to objects, including basic-level names (e.g., car) and subordinate-level names (e.g., Beetle). Which of these names is eventually selected often depends on contextual factors. The present article reports a series of picture-word interference experiments that explored how the designated target name (basic level vs. subordinate level) and contextual constraints rendering the name alternative either appropriate or inappropriate affect lexical activation and lexical choice. The experimental data demonstrate clear context effects on the eventual lexical choice. However, they also show that alternative nonselected object names are phonologically activated, even if a constraining context makes these alternative names currently inappropriate. 相似文献
963.
Semerari A Carcione A Dimaggio G Nicoló G Pedone R Procacci M 《Journal of personality disorders》2005,19(6):690-710
Many authors consider that patients suffering from Borderline Personality Disorder (BPD) are hampered in their ability to metarepresent, which is the correct ascribing of states of mind to oneself and to others and the reflecting thereon. Although the ability to mentalize is generally described as being uniform, various authors pinpoint problems which appear to be of a diverse psychological nature. Some describe difficulties in identifying emotions or a shortfall in their regulation, others identify a lack of integration between representations of self and those of others, and yet others focus on the failure to distinguish between fantasy and reality. In the present research all sessions during the first year of therapy of four patients suffering from BPD were tape-recorded and transcribed, and then analyzed using the Metacognition Assessment Scale (MAS), which is designed for the evaluation of the ability to metarepresent in clinical reports. The results support the hypothesis that there is a metarepresentation impairment in BPD but that it is more selective than was thought until now. In particular, such patients maintain their ability to identify internal states, whereas they are impaired in the integration of representations of self and others and in the differentiation between fantasy and reality. 相似文献
964.
We tested whether informing women about stereotype threat is a useful intervention to improve their performance in a threatening testing situation. Men and women completed difficult math problems described either as a problem-solving task or as a math test. In a third (teaching-intervention) condition, the test was also described as a math test, but participants were additionally informed that stereotype threat could interfere with women's math performance. Results showed that women performed worse than men when the problems were described as a math test (and stereotype threat was not discussed), but did not differ from men in the problem-solving condition or in the condition in which they learned about stereotype threat. For women, attributing anxiety to gender stereotypes was associated with lower performance in the math-test condition but improved performance in the teaching-intervention condition. The results suggest that teaching about stereotype threat might offer a practical means of reducing its detrimental effects. 相似文献
965.
Although most theories of choice are cognitive, recent research has emphasized the role of emotions. We used a novel context--the Mad Cow crisis in France--to investigate how emotions alter choice even when consequences are held constant. A field study showed that individuals reduced beef consumption in months after many newspaper articles featured the emotional label "Mad Cow," but beef consumption was unaffected after articles featured scientific labels for the same disease. The reverse pattern held for the disease-related actions of a government bureaucracy. A lab study showed that the Mad Cow label induces people to make choices based solely on emotional reactions, whereas scientific labels induce people to consider their own probability judgments. Although the Mad Cow label produces less rational behavior than scientific labels, it is two to four times more common in the environment. 相似文献
966.
In the present study, we examined how people code object location when an object is hidden in an enclosed space. On object location tasks involving disorientation, viewers must code the location of an object in relation to the spatial environment because they cannot directly track their changing relation to the object. Recently, we showed that viewers also code their perspective relative to the entire space (inside vs. outside) in such tasks. To determine whether viewers code perspective whenever they must locate an object, we examined young children's performance on a task in which coding perspective would be difficult. Our task involved both disorientation and translation (i.e., movement from inside to outside the space or vice versa). When translation preceded disorientation, performance was comparable to performance on tasks with no translation. However, when disorientation preceded translation, performance was at chance. The implications of these findings for location coding are discussed. 相似文献
967.
Findings from a complex decision-making task (the Iowa gambling task) show that individuals with neuropsychological disorders are characterized by decision-making deficits that lead to maladaptive risk-taking behavior. This article describes a cognitive model that distills performance in this task into three different underlying psychological components: the relative impact of rewards and punishments on evaluations of options, the rate that the contingent payoffs are learned, and the consistency between learning and responding. Findings from 10 studies are organized by distilling the observed decision deficits into the three basic components and locating the neuropsychological disorders in this component space. The results reveal a cluster of populations characterized by making risky choices despite high attention to losses, perhaps because of difficulties in creating emotive representations. These findings demonstrate the potential contribution of cognitive models in building bridges between neuroscience and behavior. 相似文献
968.
Unique temporal change is the key to attentional capture 总被引:2,自引:0,他引:2
Abstract— Attentional capture refers to the observation that some events break through and attract one's attention even when one is engaged in a task for which these events are irrelevant. Previous research, focusing primarily on spatial factors, has shown that a new object is more salient in this regard than an abrupt change in an object's features. Here we show that feature changes can be as effective as new objects in capturing attention, provided that they occur during a period of temporal calm. Conversely, both feature changes and new objects are far less effective in capturing attention when they occur simultaneously with other display changes, such as coincident with the initial onset of the display or with small visual transients that occur during a display transition. These results highlight the importance of considering both space and time in studies of attentional capture; the most effective stimulus is unique in both dimensions. 相似文献
969.
Neuroleptic malignant syndrome (NMS) is a life threatening medical state complicating the use of antipsychotic medications and other drugs that affect the dopaminergic system on administration or withdrawal. The condition was recognised nearly half a century ago, shortly after the discovery of antipsychotic medications. However, there are still no systematic studies about NMS. There are no definitive guidelines on its treatment. Although early recognition is emphasised and usually possible, delayed diagnosis is not rare. We here report on a case of NMS complicated by renal failure, and possibly respiratory failure. The report underscores the seriousness of delayed diagnosis and puts forward a comprehensive management recommendation based on our experience and the existing literature. 相似文献
970.
This paper reports two experiments concerned with the form of the linear function relating memory span to pronunciation rate. Experiment 1 asked whether the intercept of the equation is attributable to an interaction between modality, word-length, and serial position. The results lead us to reject this possibility. Experiment 2 examined the shape of the span function for visual presentation of lists read aloud or silently. The results show that the intercept of the span function disappears for silent presentation but not for aloud presentation. The results are discussed in terms of a balance between two opposing effects of word-length. 相似文献