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Can sentence comprehension impairments in aphasia be explained by difficulties arising from dependency completion processes in parsing? Two distinct models of dependency completion difficulty are investigated, the Lewis and Vasishth (2005) activation-based model and the direct-access model (DA; McElree, 2000). These models' predictive performance is compared using data from individuals with aphasia (IWAs) and control participants. The data are from a self-paced listening task involving subject and object relative clauses. The relative predictive performance of the models is evaluated using k-fold cross-validation. For both IWAs and controls, the activation-based model furnishes a somewhat better quantitative fit to the data than the DA. Model comparisons using Bayes factors show that, assuming an activation-based model, intermittent deficiencies may be the best explanation for the cause of impairments in IWAs, although slowed syntax and lexical delayed access may also play a role. This is the first computational evaluation of different models of dependency completion using data from impaired and unimpaired individuals. This evaluation develops a systematic approach that can be used to quantitatively compare the predictions of competing models of language processing.  相似文献   
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In recent decades, cognitive and behavioral scientists have learned a great deal about how people think and behave. On the most general level, there is a basic consensus that many judgments, including ethical judgments, are made by intuitive, even unconscious, impulses. This basic insight has opened the door to a wide variety of more particular studies that investigate how judgments are influenced by group identity, self‐conception, emotions, perceptions of risk, and many other factors. When these forms of research engage ethical issues, they are sometimes called empirical ethics. This essay argues that the field of religious ethics would benefit from a more robust engagement with empirical ethics than it has thus far undertaken. In doing so, it offers a brief account of how issues of moral psychology and moral anthropology have been treated in religious ethics, and it highlights ways that the scientific findings challenge some prevailing norms in religious ethics. It ends by suggesting avenues by which religious ethics research could productively engage empirical ethics.  相似文献   
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使用模拟研究方法比较了以往研究中提出的基于观察信息矩阵、三明治矩阵的Wald(分别表示为W_Obs、W_Sw)、似然比(Likelihood Ratio)统计量以及新提出的基于经验交叉相乘信息矩阵的Wald统计量(W_XPD)在模型——数据失拟条件下进行项目水平上模型比较时的表现。结果显示:(1)W_Sw的一类错误控制率有很强的健壮性。(2)W_XPD在Q矩阵错误设定的大多数条件下的表现优于W_Sw。结论:模型—数据拟合良好时可以使用W_Sw进行项目水平上的模型比较,当模型与数据失拟时W_XPD可能是更好的选择。  相似文献   
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在视觉搜索过程中,老年人是否可以在不同情境下调节自上而下和自下而上的加工水平尚不明确。为了探讨老化对认知灵活性的影响,研究采用空间线索范式,通过比较有效线索和无效线索来考察对线索的注意加工水平(注意捕获、注意抑制),通过比较目标相关和目标无关线索的注意加工水平来考察自上而下和自下而上的作用,通过改变分心物一致性来调控不同的目标凸显情境。结果发现,年轻组在目标非凸显时的空间线索效应高于目标凸显时,表明年轻人会依据目标凸显性调整自上而下的加工水平;但老年组却没有产生这种差异,其更依赖自上而下的加工,注意系统会对目标相关的线索进行注意捕获,对目标无关的线索进行注意抑制。结果表明,随着年龄的增长,认知控制的灵活性下降,表现出对自上而下加工较多的依赖;此外,老年人依然保留着注意捕获和注意抑制的能力,这对认知老化中抑制能力受损的观点提出了挑战。  相似文献   
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The impact of linguistic distance or the relatedness between two languages, on bilinguals’ episodic memory performance and verbal fluency is an understudied area. Thus, the purpose of this study was to determine if differences in linguistic distances have differential effects on these abilities. Measures of episodic recognition, categorical fluency, and global cognitive functioning were also considered in the analyses. Two matched samples with participants living and educated in Sweden were drawn from the Betula Prospective Cohort Study. Results showed that bilinguals who speak linguistically similar languages (Swedish and English), performed significantly better than monolinguals on both episodic memory recall and letter fluency, while bilinguals who speak two languages that are more distant (Swedish and Finnish), showed no advantages compared to their monolingual counterparts. For both tasks, however, a linear trend was observed indicative of better performance for the Swedish-English group compared to the Finnish-Swedish group, and for the Swedish-Finnish group compared to the monolinguals group. As expected, no differences between groups were found in any of the other cognitive tasks. Overall, results suggest that the impact of linguistic distances should be explored in more detail in the future.  相似文献   
128.
BackgroundTouch screen devices are now ubiquitous, and their usage by young children is increasing. However, the effects of these devices on young children are still unknown. Therefore, this study aimed to address the associations of touch screen device exposure with symptomatic emotional and behavioral problems and language development in children between the ages of 18 and 36 months.MethodA total of 161 primary caregivers of children between the ages of 18 and 36 months were recruited from the pediatric ward and outpatient clinic at a medical center in southern Taiwan. All caregivers were asked to fill out the Child Behavior Checklist for Ages 1½–5 (CBCL 1½–5) and a questionnaire on basic personal information and touch screen device usage, and they were also interviewed with the Communication and Language Screening Test for Birth to Three Chinese-Speaking Infant-Toddlers (CLST). Independent t-test and one-way ANOVA were used to examine the differences among the categories in the demographic variables and to characterize the touch screen device usage behaviors. Pearson’s correlation was used to analyze the relationship between language delay and the extent of touch screen device exposure. After primary univariate analysis, we used multiple regression models to examine the relationships among the effects of touch screen device usage behaviors on children's emotional and behavioral problems and language development.ResultThe children’s mean age was 25.63 months (SD = 5.35). Children who spent more time on touch screen devices were more likely to have emotional problems (β = .219, p < .010, 95 % CI: .279–1.518), anxious/depressive symptoms (β = .206, p < .050, 95 % CI: .170–1.244), somatic complaints (β = .291, p < .001, 95% CI: .455–1.462), social withdrawal symptoms (β = .194, p < .050, 95 % CI: 0.133–1.150), attention problems (β = .300, p < .001, 95 % CI: .432–1.267), and aggressive behaviors (β = .247, p < .010, 95 % CI: .967–3.983). The effects were not noted on language development (β = −.136, p < .100, 95 % CI: −2.595–.147).ConclusionYoung children who spent more time on touch screen devices were more likely to have emotional problems, anxious/depressive symptoms, somatic complaints, social withdrawal symptoms, attention problems, and aggressive behaviors, but not language delay.  相似文献   
129.
As a core component of most cognitive diagnosis models, the Q-matrix, or item and attribute association matrix, is typically developed by domain experts, and tends to be subjective. It is critical to validate the Q-matrix empirically because a misspecified Q-matrix could result in erroneous attribute estimation. Most existing Q-matrix validation procedures are developed for dichotomous responses. However, in this paper, we propose a method to empirically detect and correct the misspecifications in the Q-matrix for graded response data based on the sequential generalized deterministic inputs, noisy ‘and’ gate (G-DINA) model. The proposed Q-matrix validation procedure is implemented in a stepwise manner based on the Wald test and an effect size measure. The feasibility of the proposed method is examined using simulation studies. Also, a set of data from the Trends in International Mathematics and Science Study (TIMSS) 2011 mathematics assessment is analysed for illustration.  相似文献   
130.
The aim of the study was to determine the proportion of depression and cognitive sequelae among young (15-30 years) Danish TBI survivors referred to interdisciplinary evaluation through a nationwide government-initiated health initiative. The cross-sectional study is based on data from the “Danish register for young adults with acquired brain injury” on TBI survivors included from October 2013 to December 2016. The main measures were Major depression inventory, Trail making test A and B, Fluency, Word learning with selective reminding, Matrix reasoning, Coding and Glasgow outcome scale - extended (GOS-E). During the study period, 131 young TBI survivors were referred to one of five national outpatient clinics. Ninety-six had complete data and of these 14.6% fulfilled the ICD-10 diagnostic criteria for depression and 34.4% had cognitive sequelae. An association was found between depression and cognitive sequelae (= 0.004). Patients with both depression and cognitive sequelae (n = 10) had a significantly lower mean score on GOS-E (= 0.0001). Depression and cognitive sequelae were frequent and associated with a poorer global functional outcome among young TBI survivors referred within a year after trauma. This finding and the notion that only 20% of the expected TBI population was referred to this nationwide health initiative indicate an unacknowledged need for interdisciplinary follow-up.  相似文献   
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