Effects of speed of word processing on semantic access: the case of bilingualism

Bilingual speakers generally manifest slower word recognition than monolinguals. We investigated the consequences of the word processing speed on semantic access in bilinguals. The paradigm involved a stream of English words and pseudowords presented in succession at a constant rate. English-Welsh bilinguals and English monolinguals were asked to count the number of letters in pseudowords and actively disregard words. They were not explicitly told that pairs of words in immediate succession were embedded and could either be semantically related or not. We expected that slower word processing in bilinguals would result in semantic access indexed by semantic priming. As expected, bilinguals showed significant semantic priming, indexed by an N400 modulation, whilst monolinguals did not. Moreover, bilinguals were slower in performing the task. The results suggest that bilinguals cannot discriminate between pseudowords and words without accessing semantic information whereas monolinguals can dismiss English words on the basis of subsemantic information.     

Trait anxiety and impaired control of reflective attention in working memory

The present study investigated whether the control of reflective attention in working memory (WM) is impaired in high trait anxiety individuals. We focused on the consequences of refreshing—a simple reflective process of thinking briefly about a just-activated representation in mind—on the subsequent processing of verbal stimuli. Participants performed a selective refreshing task, in which they initially refreshed or read one word from a three-word set, and then refreshed a non-selected item from the initial phrase or read aloud a new word. High trait anxiety individuals exhibited greater latencies when refreshing a word after experiencing the refreshing of a word from the same list of semantic associates. The same pattern was observed for reading a new word after prior refreshing. These findings suggest that high trait anxiety individuals have difficulty resolving interference from active distractors when directing reflective attention towards contents in WM or processing a visually presented word.     

Insufficient augmentation of ambient GABA responsible for age-related cognitive deficit

Age-related degeneration of intracortical inhibition could underlie declines in cognitive function during senescence. Based on a hypothesis that a decrease in basal concentration of ambient (extrasynaptic) GABA with aging leads to depressing intracortical inhibition, we investigated how the basal concentration affects stimulus-evoked activity (as signal), ongoing-spontaneous activity (as noise) of neurons and their (signal-to-noise) ratio S/N. We simulated a neural network model equipped with a GABA transport system that regulates ambient GABA concentration in a neuronal activity-dependent manner. An increase in basal concentration augmented ambient GABA, increased GABA-mediated inhibitory current, and depressed ongoing-spontaneous activity while still keeping stimulus-evoked activity. This led to S/N improvement, for which it was necessary for the reversal potential of GABA transporter to be close to the resting potential of neurons. Above the resting potential, ongoing-spontaneous activity was predominantly enhanced due to excessive GABA-uptake from the extracellular space by transporters. Below the resting potential, stimulus-evoked activity was predominantly depressed, caused by excessive GABA-release. We suggest that the insufficient augmentation of ambient GABA due to a decrease in its basal concentration may be one of the possible causes of cognitive deficit with aging, increasing ongoing-spontaneous neuronal activity as noise. GABA transporter may contribute to improving S/N, provided that its reversal potential is close to the resting potential.     

A Bayesian Semiparametric Item Response Model with Dirichlet Process Priors

In Item Response Theory (IRT), item characteristic curves (ICCs) are illustrated through logistic models or normal ogive models, and the probability that examinees give the correct answer is usually a monotonically increasing function of their ability parameters. However, since only limited patterns of shapes can be obtained from logistic models or normal ogive models, there is a possibility that the model applied does not fit the data. As a result, the existing method can be rejected because it cannot deal with various item response patterns. To overcome these problems, we propose a new semiparametric IRT model using a Dirichlet process mixture logistic distribution. Our method does not rely on assumptions but only requires that the ICCs be a monotonically nondecreasing function; that is, our method can deal with more types of item response patterns than the existing methods, such as the one-parameter normal ogive models or the two- or three-parameter logistic models.     

Development of the overt-covert aggression inventory

The expression of anger in Japanese people is different from that of other races. We developed a new brief inventory, the Overt-Covert Aggression Inventory, to assess aggressive behavior ofJapanese people by focusing on their uniqueness and examined its reliability and validity. This inventory, the Center for Epidemiological Studies Depression scale, the Japanese version of the Buss-Perry Aggression Questionnaire, and the Picture-Frustration Study were administered to 3,104 men and 316 women in a factory. Internal consistency, test-retest reliability, concurrent validity, and construct validity of the scale were examined. We confirmed that the Overt-Covert Aggression Inventory has adequate reliability and sufficient concurrent validity, however, further studies of the construct validity and discriminant validity are required.     

Studies on the balancing,the minimal balancing,and the minimum balancing processes for social groups with planar and nonplanar graph structures

Balancing processes of social groups which transform an unbalanced group to a balanced one by changing the interpersonal relations in the group are characterized in terms of signed graphs. The graphs are given by categorizing the (interpersonal) relations within groups as positive or negative. A balanced state of a group is defined as one in which all the circuits of the graph have a positive sign, and the other cases are called unbalanced states. First, we show that a balancing process for a signed graph (changing the signs of its lines) is decomposed into that for each of the block components of the graph. Second, we classify signed graphs as planar and nonplanar. For the planar cases, we define the dual graph of a planar signed graph, and the balancing processes are characterized by specified sets of lines of the graph. According to the characterization, effective algorithms to derive the minimal and the minimum balancing processes are proposed. For the nonplanar cases, the balancing processes are characterized in terms of adjacency matrices of nonplanar signed graphs by introducing the notion of sign vectors. The characterization results in effective algorithms to derive the minimal and the minimum balancing processes. These discussions are also extended to the case where interpersonal relations have their own directions.     

Doubly Robust-Type Estimation for Covariate Adjustment in Latent Variable Modeling

Due to the difficulty in achieving a random assignment, a quasi-experimental or observational study design is frequently used in the behavioral and social sciences. If a nonrandom assignment depends on the covariates, multiple group structural equation modeling, that includes the regression function of the dependent variables on the covariates that determine the assignment, can provide reasonable estimates under the condition of correct specification of the regression function. However, it is usually difficult to specify the correct regression function because the dimensions of the dependent variables and covariates are typically large. Therefore, the propensity score adjustment methods have been proposed, since they do not require the specification of the regression function and have been applied to several applied studies. However, these methods produce biased estimates if the assignment mechanism is incorrectly specified. In order to make a more robust inference, it would be more useful to develop an estimation method that integrates the regression approach with the propensity score methodology. In this study we propose a doubly robust-type estimation method for marginal multiple group structural equation modeling. This method provides a consistent estimator if either the regression function or the assignment mechanism is correctly specified. A simulation study indicates that the proposed estimation method is more robust than the existing methods. This research was partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Young Scientists (B), 187-30406.     

Perfectionism and Self‐conscious Emotions in British and Japanese Students: Predicting Pride and Embarrassment after Success and Failure

Regarding self‐conscious emotions, studies have shown that different forms of perfectionism show different relationships with pride, shame, and embarrassment depending on success and failure. What is unknown is whether these relationships also show cultural variations. Therefore, we conducted a study investigating how self‐oriented and socially prescribed perfectionism predicted pride and embarrassment after success and failure by comparing 363 British and 352 Japanese students. Students were asked to respond to a set of scenarios where they imagined achieving either perfect (success) or flawed (failure) results. In both British and Japanese students, self‐oriented perfectionism positively predicted pride after success and embarrassment after failure, whereas socially prescribed perfectionism predicted embarrassment after success and failure. Moreover, in Japanese students, socially prescribed perfectionism positively predicted pride after success and self‐oriented perfectionism negatively predicted pride after failure. The findings have implications for our understanding of perfectionism, indicating that the perfectionism–pride relationship not only varies between perfectionism dimensions but may also show cultural variations. Copyright © 2012 John Wiley & Sons, Ltd.     

Effects of calcaneal eversion on three-dimensional kinematics of the hip, pelvis and thorax in unilateral weight bearing

Understanding the kinematic chain from foot to thorax will provide a better basis for assessment of malalignment of the body. The purpose of this study was to investigate the effects of induced calcaneal eversion on the kinematics of the hip, pelvis and thorax in three dimensions under unilateral weight-bearing. Twenty-eight healthy males were requested to stand on one leg under three conditions: normal (standing directly on the floor), and on wedges producing 5° and 10° calcaneal eversion. Recorded kinematic parameters included the angles of the hip joint, pelvis, and thorax in three dimensions. Eversion induced by wedges produced significant increases in hip flexion, hip medial rotation, pelvic anterior tilt, and thoracic lateral tilt and axial rotation to the standing side. In the frontal plane, pelvic lateral tilt to the standing side was decreased in 5° eversion condition compared with normal condition; conversely, it was increased in 10° eversion condition compared with 5° eversion condition. Arch height was negatively correlated with change in thoracic axial rotation to standing side from the normal to 10° eversion (r = −.528, p < .01). We concluded that induced calcaneal eversion affects the three-dimensional kinematics of the thorax through the hip joint and the pelvis.