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841.
The overlap model: a model of letter position coding 总被引:3,自引:0,他引:3
Recent research has shown that letter identity and letter position are not integral perceptual dimensions (e.g., jugde primes judge in word-recognition experiments). Most comprehensive computational models of visual word recognition (e.g., the interactive activation model, J. L. McClelland & D. E. Rumelhart, 1981, and its successors) assume that the position of each letter within a word is perfectly encoded. Thus, these models are unable to explain the presence of effects of letter transposition (trial-trail), letter migration (beard-bread), repeated letters (moose-mouse), or subset/superset effects (faulty-faculty). The authors extend R. Ratcliff's (1981) theory of order relations for encoding of letter positions and show that the model can successfully deal with these effects. The basic assumption is that letters in the visual stimulus have distributions over positions so that the representation of one letter will extend into adjacent letter positions. To test the model, the authors conducted a series of forced-choice perceptual identification experiments. The overlap model produced very good fits to the empirical data, and even a simplified 2-parameter model was capable of producing fits for 104 observed data points with a correlation coefficient of .91. 相似文献
842.
Corcos M Loas G Speranza M Perez-Diaz F Stephan P Verrier A Lang F Nezelof S Bizouard P Venisse JL Jeammet P 《Psychological reports》2008,102(2):435-449
Many common risk factors have been described in addictive disorders. Little is known about factors' respective contributions to discrimination of addicted and nonaddicted participants. Two large samples were compared including 513 nonpsychiatric participants and 374 addicted participants meeting the DSM-IV criteria for eating disorders, alcohol, or substance dependence. Twenty-six risk factors were assessed by interview or self-rating scales. A discriminant analysis determined the respective weight of each risk factor. One discriminant function emerged and characterized a depressive dimension. The results suggest that the different risk factors described in addiction could be related to a depressive dimension. 相似文献
843.
This study examined novel-object preference in dogs. In a free choice test 17 dogs were presented with a novel toy in a line up with two familiar toys. The unfamiliar object was chosen first in 38 out 50 tests suggesting a strong preference for novel over familiar items. Neophilia may be an adaptive trait for domestic dogs that has helped their adaptation towards man. 相似文献
844.
This article examines the importance of semantic processes in the recognition of emotional expressions, through a series of three studies on false recognition. The first study found a high frequency of false recognition of prototypical expressions of emotion when participants viewed slides and video clips of nonprototypical fearful and happy expressions. The second study tested whether semantic processes caused false recognition. The authors found that participants made significantly higher error rates when asked to detect expressions that corresponded to semantic labels than when asked to detect visual stimuli. Finally, given that previous research reported that false memories are less prevalent in younger children, the third study tested whether false recognition of prototypical expressions increased with age. The authors found that 67% of eight- to nine-year-old children reported nonpresent prototypical expressions of fear in a fearful context, but only 40% of 6- to 7-year-old children did so. Taken together, these three studies demonstrate the importance of semantic processes in the detection and categorization of prototypical emotional expressions. 相似文献
845.
Justus T Larsen J de Mornay Davies P Swick D 《Cognitive, affective & behavioral neuroscience》2008,8(2):178-194
Neuropsychological dissociations between regular and irregular English past-tense morphology have been reported using a lexical decision task in which past-tense primes immediately precede present-tense targets. We present N400 event-related potential data from healthy participants using the same design. Both regular and irregular past-tense forms primed corresponding present-tense forms, but with a longer duration for irregular verbs. Phonological control conditions suggested that differences in formal overlap between prime and target contribute to, but do not account for, this difference, suggesting a link between irregular morphology and semantics. Further analysis dividing the irregular verbs into two categories (weak irregular and strong) revealed that priming for strong verbs was reliably stronger than that for weak irregular and regular verbs, which were statistically indistinguishable from one another. We argue that, although we observe a regular-irregular dissociation, the nature of this dissociation is more consistent with single- than with dual-system models of inflectional morphology. 相似文献
846.
聋童执行功能发展:聋童与正常儿童的比较 总被引:6,自引:0,他引:6
利用标准Dimensional Change Card Sort任务(DCCS),对76名智力正常的3~8岁聋童和78名3~5.5岁的正常儿童进行了对比测试,旨在考察聋童执行功能发展的年龄特征与发展水平。结果发现,3岁组的聋童和正常儿童在DCCS任务上的表现没有显著性差异,但正常儿童在4~4.5岁时进入一个迅速发展期,而聋童要在6岁时才有快速的发展,到7岁后才相当于正常儿童5岁的发展水平,大约滞后2年。研究认为,造成聋童执行功能发展滞后的原因主要有:(1)语言符号系统和聋童特有的符号系统之间可能存在的差异;(2)聋童可能存在计划和灵活性的缺陷;(3)聋童可能存在命名和标识策略上的困难和注意机制的缺陷。结合关于聋童心理理论发展滞后于正常儿童7年以上的报道,心理理论发展和执行功能发展在聋童身上表现出较大的不一致性。 相似文献
847.
医疗价格过度增长的管制原因分析 总被引:1,自引:0,他引:1
医疗服务的准公共产品特征说明医疗价格问题不能完全由市场来解决,政府必须对医疗价格进行管制。造成医疗价格高昂的原因是多样的和复杂的,基于对医疗价格的政府管制现状分析,认为对医疗价格的管制不善,是导致中国高昂医疗价格的原因之一,并且提出了对医疗价格进行管制的制度框架。 相似文献
848.
849.
This study examined the association between prenatal exposure to cigarettes and infant and maternal negative affect. Participants were 115 mother-infant dyads (69 prenatally exposed to cigarettes and 46 nonexposed). Infant and maternal negative affect were both assessed during the neonatal period (2-4 weeks of age) and again at 7 months of infant age. Results indicated that only prenatal exposure to cigarettes predicted infant negative affect. Infants who were prenatally exposed to more cigarettes had higher levels of negative affect at both time points. Furthermore, regression analyses indicated that both infant and maternal negative affect during the neonatal period predicted maternal negative affect at 7 months of age. These results highlight the importance of considering the reciprocal relationship between infant and maternal behavior when examining developmental outcomes among infants prenatally exposed to cigarettes. 相似文献
850.
Forget-Dubois N Boivin M Dionne G Pierce T Tremblay RE Pérusse D 《Infant behavior & development》2007,30(3):453-465
Children's negative characteristics are thought to be a factor in evoking hostile parenting responses. This can result in genotype/environment correlations (rGE) in which children's heritable traits influence the parenting they experience. We did genetic analyses on 292 mothers' self-reported hostile-reactive behaviors toward each of their twins at 5, 18 and 30 months. Finding heritability for a parenting behavior analyzed as a child phenotype is evidence of rGE correlation. The heritability of maternal behavior was modest (29% at 5 months, 0% at 18 months, and 25% at 30 months) and longitudinal analyses indicated that genetic factors at 5 and 30 months were uncorrelated. Common environment factors, probably reflecting characteristics of the mothers, were the main source of variance at the three ages and were highly correlated through time. We concluded that children's heritable characteristics evoked maternal negative response at specific times, but were not responsible for the stability of maternal hostility from infancy to toddlerhood. 相似文献