The Relative Contribution of Diagnostic and Psychosocial Variables to Severity of Suicidal Ideation

The present study examined the relative contribution of diagnostic and psychosocial factors to the prediction of severity of suicidal ideation in a sample of 78 college students. Using hierarchical regression analyses to control for each set of factors, psychosocial variables were found to consistently predict level of suicidal ideation. In contrast, diagnostic variables including diagnosis of substance abuse and composite scores for depression and anxiety were unrelated to level of suicidality. An examination of individual diagnoses revealed no predictable relationships with severity of suicidality in this population. The results were discussed from several methodological viewpoints.     

The study of early emotion processing in the frontal area using a two-dipole source model

The present study explored early emotion processing in the frontal area using the two-dipole source model. The 21-channel recordings of event-related potentials (ERPs) produced by a pure tone were analyzed in order to assess information processing. In the test conditions, the pure tone followed the presentation of one of two unpleasant sounds to enhance anxiety. In the control condition, only the pure tone was presented. There were two groups of eight subjects, one with low scores for trait anxiety and one with high scores. The ERPs were separately averaged for the groups, as well as for the high- and low-anxiety sound and control session. A negative peak around 120 ms (C2) and a positive peak around 280 ms (C5) after stimulus onset were identified in all the sessions. The two-dipole source model was applied to these two components. In the C2 component, dipole sources were located in the left frontal area in the control sessions, and in the right frontal area in the high-anxiety sessions. This activation pattern was clearer in the group with low trait anxiety. In contrast, with the C5 component, lateralization of the dipole source in the frontal area was not seen. These findings suggest that the frontal area is involved in early emotion processing. A dual-stage model of emotion processing is therefore proposed.     

Initial excitatory conditioning with the truly random control procedure in rats: The effects of density of the conditioned stimulus

The present experiments were designed to test whether initial excitatory conditioning to a stimulus was obtained, using a within-subject design of the truly random control (TRC) procedure, and to examine the effects of the density of the conditioned stimulus on it. In Experiment 1, the effect of the three levels of CS density (50%, 25%, 20%) was assessed at six different stages of training, using the conditioned suppression of licking in rats. Although all of the groups given the TRC procedure showed evidence of initial excitatory conditioning, it was more marked in the group with the highest CS density than in the other groups. Experiment 2 confirmed the results of Experiment 1, using a between-subject design. The findings are in line with predictions from the Rescorla-Wagner model, and are discussed with reference to other contemporary theories of associative learning.     

Stepwise variable selection in factor analysis

It is very important to choose appropriate variables to be analyzed in multivariate analysis when there are many observed variables such as those in a questionnaire. What is actually done in scale construction with factor analysis is nothing but variable selection.In this paper, we take several goodness-of-fit statistics as measures of variable selection and develop backward elimination and forward selection procedures in exploratory factor analysis. Once factor analysis is done for a certain numberp of observed variables (thep-variable model is labeled the current model), simple formulas for predicted fit measures such as chi-square, GFI, CFI, IFI and RMSEA, developed in the field of the structural equation modeling, are provided for all models obtained by adding an external variable (so that the number of variables isp + 1) and for those by deleting an internal variable (so that the number isp – 1), provided that the number of factors is held constant.A programSEFA (Stepwise variable selection in Exploratory Factor Analysis) is developed to actually obtain a list of the fit measures for all such models. The list is very useful in determining which variable should be dropped from the current model to improve the fit of the current model. It is also useful in finding a suitable variable that may be added to the current model. A model with more appropriate variables makes more stable inference in general.The criteria traditionally often used for variable selection is magnitude of communalities. This criteria gives a different choice of variables and does not improve fit of the model in most cases.The URL of the programSEFA is http://koko15.hus.osaka-u.ac.jp/~harada/factor/stepwise/.     

Optimal scaling by alternating length-constrained nonnegative least squares, with application to distance-based analysis

An important feature of distance-based principal components analysis, is that the variables can be optimally transformed. For monotone spline transformation, a nonnegative least-squares problem with a length constraint has to be solved in each iteration. As an alternative algorithm to Lawson and Hanson (1974), we propose the Alternating Length-Constrained Non-Negative Least-Squares (ALC-NNLS) algorithm, which minimizes the nonnegative least-squares loss function over the parameters under a length constraint, by alternatingly minimizing over one parameter while keeping the others fixed. Several properties of the new algorithm are discussed. A Monte Carlo study is presented which shows that for most cases in distance-based principal components analysis, ALC-NNLS performs as good as the method of Lawson and Hanson or sometimes even better in terms of the quality of the solution. Supported by The Netherlands Organization for Scientific Research (NWO) by grant nr. 030-56403 for the “PIONEER” project “Subject Oriented Multivariate Analysis” to the third author. We would like to thank the anonymous referees for their valuable remarks that have improved the quality of this paper.     

生物芯片技术与缩微实验室

基于微加工技术发展起来的生物芯片,可以把成千上万乃至几十万个生命信息集成在一个很小的芯片上,对基因、抗原和活体细胞等进行分析和检测。用这些生物芯片制作的各种生化分析仪和传统仪器相比较具有体积小、重量轻、便于携带、无污染、分析过程自动化、分析速度快、所需样品和试剂少等诸多优点。这类仪器的出现将给生命科学研究、疾病诊断和治疗、新药开发、生物武器战争、司法鉴定、食品卫生监督、航空航天等领域带来一场革命。     

Single Session Treatment of Test Anxiety with Eye Movement Desensitization and Reprocessing (EMDR)

One session of Eye Movement Desensitization and Reprocessing (EMDR) appeared to be an effective treatment for test anxiety, reducing reported physiological distress, worry, and fears of negative evaluation. The research design included two components: a comparison study, comparing Immediate Treatment and Wait List groups, and a replication study, comparing the treatment response of Immediate and Delayed (Treated Wait List) groups. Seventeen test anxious university students were randomly assigned to one session of EMDR or Wait List. At post-test, the Immediate group demonstrated significant improvement, compared to the Wait List group, on the Test Anxiety Inventory (TAI) and Fear of Negative Evaluation Scale. Treatment effects were maintained at follow-up. The Wait List group received treatment after post-measures were taken. Treatment of the Delayed group replicated effects. Improvement was reflected by large treatment effect sizes and a decrease in percentile ranking on the TAI from the 90th to the 50th percentile.     

元记忆监测与人格特征相互关系的实验研究

运用ＲＪＲ标准程序,考察了元记忆监测与两种人格维度（内外向以及情绪性）的关系,结果表明：元记忆监测水平受到了人格自身优势倾向性及其行为定向性的影响,人格的内外向特点和情绪稳定性特点直接制约着元记忆监测的准确性和稳定性。据此认为元记忆能力的度量和开发,应充分考虑人格因素的影响。     

连绵词语音类似的启动效应

研究采用快速启动范型考察了视觉连绵词加工中语音的自动激活.两个实验发现,无论是首字同音还是尾字同音启动都可以促进对连绵词的命名反应,且基本不受目标词熟悉性(词频高低)及真假词的影响.可以推断,至少在连绵词--这种单词素词的词汇通达中存在语音的自动激活,这种语音的激活可以说是前词的装配与词水平上的改变.     

序列位置内隐学习产生机制的实验研究

内隐学习是当今认知和学习领域继内隐记忆之后又一重要的研究课题。该研究利用序列反应时研究程式,通过两个实验,对序列位置内隐学习产生的机制进行了探讨。结果表明：（１）在序列反应时任务程式中,随着反应一刺激间隔的延长,序列位置内隐学习的学习量逐渐减少;（２）异形同模式迁移组和异形异模式迁移组被试间内隐学习量无显著差异,被试未能内隐地习得抽象的序列模式。说明序列位置内隐学习产生的基础是水平联结,在该实验条件下没有发现垂直联结存在的证据。