Validation of the Japanese version of the NEO Five-Factor Inventory in a large community sample

The NEO Five-Factor Inventory is the shortened version of the Revised NEO Personality Inventory. The aim of this study was to examine the reliability and validity of the Japanese version of the shortened version in the general population of Japan. This version was translated into Japanese and then administered to 2,051 adults in a rural town in Akita Prefecture. A total of 1,664 (81.1%) individuals gave valid answers. Internal reliability, assessed by Cronbach alpha for subscales, ranged from .60 to .77. The scales were only weakly correlated both with each other and with age. In a multiple regression analysis, only the Neuroticism scale score was a significant predictor of scores on the General Health Questionnaire. Factor analysis supported the theoretical structure of personality. Overall, the Japanese version showed good reliability and validity in this sample of the general population of Japan.     

Effect of an observer's presence on facial behavior during dyadic communication

In everyday life, people communicate not only with another person but also in front of other people. How do people behave during communication when observed by others? Effects of an observer (presence vs absence) and interpersonal relationship (friends vs strangers vs alone) on facial behavior were examined. Participants viewed film clips that elicited positive affect (film presentation) and discussed their impressions about the clips (conversation). Participants rated their subjective emotions and social motives. Durations of smiles, gazes, and utterances of each participant were coded. The presence of an observer did not affect facial behavior during the film presentation, but did affect gazes during conversation. Whereas the presence of an observer seemed to facilitate affiliation in pairs of strangers, communication between friends was exclusive and not affected by an observer.     

Genetic and environmental relationships between head circumference growth in the first year of life and sociocognitive development in the second year: a longitudinal twin study

Although growth in head circumference (HC) during infancy is known to predict later childhood outcomes, the mechanisms underlying this association with later sociocognitive abilities remain undetermined. Thus, using a sample of 241 pairs of normally developing Japanese twins, this study investigated the underpinnings of the association between HC growth (difference between HC at birth and at 10 months) and sociocognitive abilities at 19 months as measured by 10 items from the M-CHAT. Phenotypic correlations between HC at birth and sociocognitive abilities and between HC growth and sociocognitive abilities were marginal and not significant. However, multivariate genetic analyses using Cholesky decomposition revealed that genetic influences on HC growth and those on sociocognitive abilities were negatively associated. On the other hand, shared and nonshared environmental influences on HC growth were positively associated with influences on sociocognitive abilities. Genetic and environmental influences on HC at birth were not significantly associated with influences on sociocognitive abilities. These results help to clarify the role of brain growth during infancy in the subsequent development of sociocognitive abilities and highlight the importance of examining the different roles of genetic and environmental influences in studies of these areas.     

The Organization of Extrinsic Neurons and Their Implications in the Functional Roles of the Mushroom Bodies in Drosophila melanogaster Meigen

Although the importance of the Drosophila mushroom body in olfactory learning and memory has been stressed, virtually nothing is known about the brain regions to which it is connected. Using Golgi and GAL4–UAS techniques, we performed the first systematic attempt to reveal the anatomy of its extrinsic neurons. A novel presynaptic reporter construct, UAS-neuronal synaptobrevin–green fluorescent protein (n-syb–GFP), was used to reveal the direction of information in the GAL4-labeled neurons. Our results showed that the main target of the output neurons from the mushroom body lobes is the anterior part of the inferior medial, superior medial, and superior lateral protocerebrum. The lobes also receive afferents from these neuropils. The lack of major output projections directly to the deutocerebrum’s premotor pathways discourages the view that the role of the mushroom body may be that of an immediate modifier of behavior. Our data, as well as a critical evaluation of the literature, suggest that the mushroom body may not by itself be a “center” for learning and memory, but that it can equally be considered as a preprocessor of olfactory signals en route to “higher” protocerebral regions.     

Multiplicative effects of intention on the perception of bistable apparent motion

When viewing ambiguous displays, observers can, via intentional efforts, affect which perceptual interpretation they perceive. Specifically, observers can increase the probability of seeing the desired percept. Little is known, however, about how intentional efforts interact with sensory inputs in exerting their effects on perception. In two experiments, the current study explored the possibility that intentional efforts might operate by multiplicatively enhancing the stimulus-based activation of the desired perceptual representation. Such a possibility is suggested by recent neurophysiological research on attention. In support of this idea, when we presented bistable apparent motion displays under stimulus conditions differentially favoring one motion percept over the other, observers' intentional efforts to see a particular motion were generally more effective under conditions in which stimulus factors favored the intended motion percept.     

Emotion space as a predictor of binocular rivalry

In our 1999 report, we examined robustness of a two-dimensional structure of facial expressions of emotion under the condition of some perceptual ambiguity, using a stereo-scope. The current study aimed to replicate and extend the previous work by adding facial photographs of different persons and by measuring participants' perception of stereoscopically presented faces. Multidimensional scaling provided a two-dimensional configuration of facial expressions comparable with the previous studies. Although binocular rivalry was a less frequent phenomenon, it was suggested that the distances between facial expressions in the derived space were a contributing factor in eliciting binocular rivalry.     

Numerical competence in rats (Rattus norvegicus): Davis and Bradford (1986) extended

The task of rats (Rattus norvegicus) was to enter 1 box of a defined ordinal number among an array of boxes. In Experiments 1 and 2, the rats correctly chose the 4th box from arrays of 6 and 12 boxes, respectively. In Experiments 3 and 4, in which the ordinal number of the correct box was increased in a graduated fashion, they were able to select the correct box even when its position was higher than 10th among 12 and 18 boxes, respectively. In Experiment 5, the possibility that the rats had used cues to the openability of the box doors was ruled out. In Experiments 6 and 7, the rats succeeded in the task even when the total number of boxes was varied from trial to trial. In Experiment 8, both small- and large-sized boxes were used to control for the possibility of using the cumulative length of the boxes as a cue. Overall, the results suggest that performance was based on numerical cues. Intentional acts were occasionally observed but appeared not to be essential for solving the task.     

Reliability and validity of a Japanese version of the Eating Disorder Inventory

The rapid increase of patients with eating disorders in Japan has male necessary the reliable and valid measurement of psychological factors in eating disorders. The purpose of this study was to examine the reliability and validity of the Japanese version of the Eating Disorder Inventory. 766 females without eating disorders and 139 female patients with eating disorders responded to the Eating Attitude Test and the Eating Disorder Inventory. Principal factor extraction with promax rotation isolated 9 interpretable factors with satisfactory internal consistency (Cronbach alpha range=.74-.90). Compared with controls, patients scored significantly higher on all factors after minimizing the influence of Body Mass Index. There were strong correlations among factor scores and scores on the Eating Attitudes Test, particularly among patients. These results indicate the Eating Disorder Inventory as showing psychometrically sound internal consistency and concurrent validity.