Effect of baseline self-efficacy on physical activity and psychological stress after a one-week pedometer intervention

Physical activity and psychological stress were hypothesized to improve more in participants with high self-efficacy than in those with low and medium self-efficacy after a one-week intervention. 39 female university students participated. The intervention had two steps: a lecture on self-monitoring and goal setting (160 min.) and a one-week pedometer intervention. Analyses were conducted on tertile groups according to self-efficacy at baseline. Pedometer step counts were higher in the high self-efficacy group than in the low self-efficacy group after intervention. Helplessness decreased time dependently after intervention only in the high-self-efficacy group. Because physical activity improved more in the high self-efficacy group after a one-week intervention, one hypothesis was supported.     

Forms of Aggression,Social-Psychological Adjustment,and Peer Victimization in a Japanese Sample: The Moderating Role of Positive and Negative Friendship Quality

The purpose of these studies was to examine the frequency and stability of relational and physical aggression and their associations with social-psychological adjustment or peer victimization, and how friendships are involved in the relations between forms of aggression and peer victimization in Japanese children. The sample consisted of 452 (Study 1) and 138 (Study 2) children who were in the fourth and fifth grades. Results of Study 1 demonstrated that relational aggression was uniquely and more strongly associated with internalizing adjustment problems than physical aggression. Moreover, Study 2 revealed that relational aggression and physical aggression were stable over a 6-month period and the stability of relational aggression was reinforced by negative friendships (i.e., high levels of exclusivity and friend victimization). Further, the association between relational aggression and relative increases in relational victimization was attenuated by positive friendships (i.e., high levels of intimacy, companionship, and friendship satisfaction). Interestingly, friendships were unrelated to physical aggression and its relation to physical victimization. The age and gender of the children in the two studies were also examined. Cultural and developmental processes involving forms of aggression, friendships, social-psychological adjustment, and peer victimization were discussed.     

The association of relational and physical victimization with hostile attribution bias,emotional distress,and depressive symptoms: A cross‐cultural study

The purpose of the present study was to examine the association between relational victimization and socio‐cognitive patterns (i.e. hostile attribution biases and emotional distress) or social–psychological adjustment problems (i.e. depressive symptoms) in Japanese and European American children (N = 272; ages 9–10). Results showed that relational victimization, which was conceptually different from physical victimization, was associated with a greater level of emotional distress for an overall sample; however, the links between relational victimization and hostile attribution biases and depressive symptoms were evidenced only for Japanese children. A follow‐up analysis revealed that hostile attribution biases had a direct effect on depressive symptoms for European American children; however, these biases mediated the link between relational victimization and depressive symptoms for Japanese children. These findings are discussed from normative and cross‐cultural perspectives.     

Perceived distance of targets in convex mirrors

We investigated the perceived distance of targets in convex and plane mirrors. In Experiment 1, 20 subjects matched the distance of targets in a real scene to the distance of a virtual target in different mirrors. The matched distances were much larger for convex mirrors than for a plane mirror. In Experiment 2, 20 subjects viewed two targets in a mirror and adjusted their own positions so that the distance to the closer target was perceived to equal the distance between the targets. The mean distance to the closer target was smaller for the convex mirrors than for the plane mirror. In Experiment 3, 20 subjects adjusted the position of a target so that the distance to it in a mirror was perceived to equal the distance designated by the experimenter. The best-fitting power functions showed that the scaling factors were larger for the convex mirrors than for the plane mirror, but the exponents were smaller for the convex mirrors than for the plane mirror. It is suggested that distance in the convex mirrors was perceived to be larger than in the plane mirror, and that the growth of perceived distance in the convex mirrors was slower than in the plane mirror.     

Development of infants’ intuitions about support relations: sensitivity to stability

Can infants perceive stability when a supported box is put on a supporting box in a balanced position? In Experiment 1, 41 infants saw three events. In a stable event, the supported box was put on a wide supporting box in a balanced position. In an unstable event, the supported box was put on a narrow supporting box in a balanced position. In an impossible event, the supported box was put on the extreme end of a wide supporting box. Infants 4 to 6.5 months old looked equally at all three events. Infants 6.5 to 10 months old looked slightly longer at the impossible event than at the other events. Infants 10 to 13 months old looked reliably longer at the unstable and impossible events than at the stable event. The results of Experiment 2 indicate that these differences in looking times did not come from differences in stimulus configurations between the events. These results suggest that infants above 10 months old are sensitive to stability of support relations.     

Preadolescents' borderline personality features in a non‐Western urban context: Concurrent and longitudinal associations with physical and relational aggression,friendship exclusivity and peer victimization

The present study examined children's borderline personality features and their association with developmentally appropriate factors, including friendship exclusivity, forms of aggression and peer maltreatment with a non‐Western urban sample. The participants consisted of 234 Japanese preadolescents who were in the fourth and fifth grade (50% girls; ages: 9–11). Results of correlational analyses show that borderline personality features were stable during a six‐month period (r = 0.55). Moreover, results of mixed linear models indicate that friendship exclusivity was associated with elevated borderline personality features concurrently and longitudinally, after controlling for the effects of physical and relational aggression. Physical aggression (not relational aggression) and physical victimization (not relational victimization) also predicted relative increases in borderline personality features. These findings are discussed from a cultural‐developmental perspective.