More efficient parameter estimates for factor analysis of ordinal variables by ridge generalized least squares

Data in psychology are often collected using Likert‐type scales, and it has been shown that factor analysis of Likert‐type data is better performed on the polychoric correlation matrix than on the product‐moment covariance matrix, especially when the distributions of the observed variables are skewed. In theory, factor analysis of the polychoric correlation matrix is best conducted using generalized least squares with an asymptotically correct weight matrix (AGLS). However, simulation studies showed that both least squares (LS) and diagonally weighted least squares (DWLS) perform better than AGLS, and thus LS or DWLS is routinely used in practice. In either LS or DWLS, the associations among the polychoric correlation coefficients are completely ignored. To mend such a gap between statistical theory and empirical work, this paper proposes new methods, called ridge GLS, for factor analysis of ordinal data. Monte Carlo results show that, for a wide range of sample sizes, ridge GLS methods yield uniformly more accurate parameter estimates than existing methods (LS, DWLS, AGLS). A real‐data example indicates that estimates by ridge GLS are 9–20% more efficient than those by existing methods. Rescaled and adjusted test statistics as well as sandwich‐type standard errors following the ridge GLS methods also perform reasonably well.     

情绪体验与认知负荷对工作记忆影响的实证研究

该研究以认知负荷为调节,探讨了不同的情绪体验对工作记忆的影响情况。采用2(认知负荷:低负荷;高负荷)×3(情绪刺激图片:愉快、厌恶、中性)两因素混合实验设计,对57名被试进行了单独实验。结果发现:(1)在低认知负荷上,被试在不同情绪体验下的反应时差异不显著,但在高认知负荷任务上,与中性情绪体验相比,被试在愉快情绪体验下的反应时显著增长,而在厌恶情绪体验下的反应时显著变短;(2)在低认知负荷上,被试在不同情绪体验下的正确率差异不显著,但在高认知负荷任务上,与中性情绪体验相比,被试在愉快情绪体验下的正确率显著提高,而在厌恶情绪体验下的正确率显著降低。该结果表明,在低认知负荷上,情绪体验对工作记忆的刷新功能不产生影响;在高认知负荷上,情绪体验对工作记忆的刷新功能影响显著,其中愉快体验具有显著的促进作用。     

肥胖成因的解释——基于食物奖赏研究的视角

肥胖的形成和发展受生物、心理和社会因素的共同作用,其中食物奖赏对肥胖的产生有重要的作用。食物是一种自然奖赏,它指机体天生对食物的渴望和依赖。食物奖赏包括"wanting"、"liking"以及"learningreinforcement"三个成分,每个成分由相应的神经通路表征。食物奖赏调控机体的摄食行为并以此调控体重变化。目前,关于肥胖与食物奖赏关系的理论模型主要有刺激—敏感化理论、奖赏过度理论以及奖赏不足理论。采用横断面设计、前瞻研究设计和纵向被试内重复测量设计,使用食物图片线索和直接给予美味奶昔的技术方法,人类脑成像研究从不同侧面为以上三个理论模型提供了证据。除此之外,食物奖赏还受基因的调控。目前,研究者关注较多的是多巴胺D2受体基因Taq IA rs1800497的多态性和FTO基因rs9939609的多态性对食物奖赏及体重改变的调控。     

不同性质汉语否定句心理加工过程的实验研究

采用词汇/图片判断范式,以不同性质的否定句和其对应的肯定句为实验材料,以词汇/图片判断的反应时和正确率为因变量指标,探讨不同性质汉语否定句的加工是否是动态变化的过程。研究分为两个大实验四个小实验。实验一采用句图匹配任务,否定句是对具体现实情境的否定,实验1a和1b分别考察句图短时间间隔和长时间间隔下否定意义的加工。实验二采用词汇判断任务,实验材料为隐喻形式的否定句。实验2a和2b分别为句词短时间间隔和长时间间隔。实验1发现短时间间隔时,句图不匹配条件下图片判断时间短于匹配时;长时间间隔时相反,句图匹配条件下图片判断时间更短。实验2发现短时间间隔时,句词不匹配条件下词汇判断时间短于匹配时,而长时间间隔时匹配与否的词汇判断时间无差异。综合两个实验结果表明,对现实情境的具体否定句符合两阶段模拟加工,被否定意义在加工早期被表征,但会因句子实际意义的通达而得到抑制;而隐喻形式的抽象否定句加工更符合抑制/保存假说,被否定意义在加工早期被表征,并在加工后期仍保留在头脑中。     

The role of vowel formant frequencies and duration in the perception of foreign accent

ABSTRACT

This study used synthesis to manipulate vowel formant frequencies and durations to evaluate their role on foreign accent perception. Formant frequencies and durations for the vowels /æ/, /?/, and /a/ were manipulated with changes toward and away from the mean native English and Spanish-accented values from Sidaras, S. K., Alexander, J. E. D., & Nygaard, L. C. (2009. Perceptual learning of systematic variation in Spanish-accented speech. The Journal of the Acoustical Society of America, 125, 3306–3316). Native listeners rated these stimuli on degree of accentedness and comprehensibility. Gradual changes in formant frequencies from native to non-native values impacted /a/ negatively, /?/ positively, and /æ/ minimally. Effects of vowel duration on either type of ratings were small and restricted to vowel-specific interactions. The current findings suggest that vowel formant frequencies are primary cues to foreign accent. Their influence depends upon whether or not frequencies could reflect alternative vowel categories.     

左侧额下回在句子语义整合加工中的作用

语义整合帮助人们在阅读理解中将小信息块整合成一个完整、连贯的句子意义表达, 是阅读理解中非常重要的认知过程。通过对比40多篇句子加工相关的脑机制研究, 发现左侧额下回在fMRI研究中是参与语义整合加工激活概率最高的区域, 而颞叶及后部是MEG研究中激活概率最高的区域。另外, 左侧额下回是如何参与语义整合、它在内隐和外显语义整合中的机制是否相同、以及这种整合加工与一般的控制性加工、词汇启动的关系都是研究者广泛关注的问题。本文对上述问题进行了详细的综述和讨论。     

识别电位认知功能探析

识别电位(Recognition Potential, RP)是被试看到可识别视觉刺激时, 在200~250ms内达到峰值的脑电反应。识别电位的研究正处于理论探讨阶段, 有两种主要观点用于解释RP。一种观点强调RP反映了视知觉分析成分; 另一种观点强调RP反映了语义或概念加工成分。两种观点至今未达成一致。最近, 针对两种观点质疑, 研究者们提出了类别特征加工的观点, 这一新观点在理论上符合大脑经济性的原则, 具有一定的优越性, 但尚需要更多的实证研究的支持。未来的RP研究应从实验材料的多样化、多研究方法结合、类别特征加工能力的习得机制等方面展开。     

A method for cross-cultural adaptation of a verbal memory assessment

Verbal memory tests—although important to the neuropsychological assessment of memory—are biased to many cultures. In the present article, we highlighted the limitations associated with the direct translation of tests and word matching, as well as the lack of ecological validity and cultural appropriateness when tests developed in one culture are used in another. To overcome these limitations, a verbal memory paradigm was developed that framed the memory assessment with a shopping-list format, but that developed culturally specific stimuli for the different language groups. The aim of the present study was to determine the equivalence of this shopping list memory test in different cultural and language groups. Eighty-three adults from English-, French-, Malay-, and Chinese-speaking cultures participated in four experiments. The results of all the experiments indicated that performance of verbal list learning is equivalent, irrespective of the language used. These results support the use of this methodology for minimizing cross-cultural test bias, and have important implications for testing culturally and linguistically diverse individuals.     

事件后信息影响目击证言准确性的实验研究

本研究探讨了不同案件类型、不同性别及给予不同的事件后信息对目击证言的影响,征集了男女大学生被试101名,进行了实验研究,研究结果如下:(1)以主体信息的记忆成绩为因变量,性别、案件类型和事件后信息为白变量,得出案件类型主效应显著,事件后信息的主效应显著,性别主效应以及各因素的交互作用都不显著;(2)以情境信息的记忆成绩为因变量,性别、案件类型和事件后信息为自变量,得出事件后信息主效应显著,案件类型和事件后信息之间交互作用效应显著;(3)不同性别、接受不同案件信息的被试对不同信息记忆的确信程度有所不同.     

Identification of biological neurons using adaptive observers

Change detection performance is influenced by a number of factors, among which is the informativeness of targets. It has not been clarified, yet, whether the highly informative regions have a processing priority as a result of resource deployment from other tasks or whether it results from a better resource management. In this paper, we adopted a change detection paradigm in which thirty participants were randomly assigned to two groups: single (change detection task) and dual task [change detection and a simplified version of the Paced Auditory Serial Oppository Task (PASOT, Gow and Deary in J Clin Exp Neuropsychol 26:723–736, 2004), which implies a verbal effort]. Stimulus informativeness was defined as social relevance, that is, changing targets were people (high relevance) versus objects (low relevance), all other aspects (i.e., salience and position in the scene) kept constant. As hypothesized, data analyses showed a significant main effect of social relevance and task condition, i.e., better change detection performance and lower change detection times for people versus objects and for single than for dual task condition. Interestingly, the PASOT accuracy remained stable across the person versus object trials, thus implying that the better performance with socially relevant targets could not be explained by a resources withdrawal from the secondary task.