Development of prosociality and a trajectory in prosocial behaviors have been a major interest among developmental psychologists. The present study investigates age-related changes in prosocial behaviors from middle childhood to early adolescence based on the relational approach, emphasizing relations with the recipients of the prosocial behaviors (i.e., prosocial behavior toward family, strangers, and friends). A total of 1,829 Japanese students (944 boys and 885 girls) from mid-elementary and junior high schools (ages 9―14 at the time of the first measurement) participated in a one-year longitudinal study. This sample consisted of five cohorts: the 4th, 5th, 6th, 7th, and 8th grade samples. The results of the latent difference score model showed a decrease in prosocial behaviors once, as mean level of individual changes; while at the same time, the model indicated a bounce-back in prosociality after the middle of the junior high school period. Additionally, we found unique changes in prosocial behaviors toward family in the form not following the overall developmental trajectory.

This study examined the associations between sexual orientation, interpersonal factors, response styles, and mental health. A total of 1,330 graduate and undergraduate students—205 LGBs (lesbians, gays, and bisexuals) and 1,125 heterosexuals—completed a questionnaire on the topics of interpersonal stress, social support, two types of response styles (rumination and problem-solving), depression, and anxiety. The analysis of variance results indicated that LGB respondents reported more rumination and interpersonal stress and less social support than heterosexual respondents. Moreover, path and mediation analyses revealed that sexual orientation can increase depression and anxiety through interpersonal factors that promote rumination or inhibit problem-solving. These results suggest that LGB youth experience greater stress in interpersonal relationships, and this stress promotes maladaptive response styles that can exacerbate mental health.

The purpose of this study is to investigate the effect of numeracy on risk and benefit perceptions of food. Previous studies have shown that people tend to rely on affect feelings when appraising risk and benefit. These studies have also shown that people manifest an inverse relationship between perceived risk and benefit. However, there have not been so many studies about the roles of numeracy and critical thinking on balanced perceptions of risk and benefit. Therefore, the present study used two online surveys to clarify their roles. Results showed that people with higher numeracy had better comprehension of food risk/benefit information. Results also showed that perceived risk and benefit had a positive correlation for people with higher numeracy after information had been provided. These results were similar between Study 1 on coffee (N = 461) and Study 2 on red and processed meat (N = 496). The results suggest that people with higher numeracy have balanced perceptions of food risk/benefit, relying more on numerical information than on affect.

This paper proposes a new Japanese version of the Remote Associates Task (RAT). In a process of solving an insight problem, people often come to an impasse and end with an experience of surprise (“Aha!”) when they finally find their solution or are informed of the correct solution. We devised a set of 80 RAT problems that were intended to have the solver reach an impasse by evoking a certain fixed term. Two experiments showed that people have a stronger “Aha!” experience when they encounter the new RAT than the one proposed previously. The current paper provides a list of problems from the new RAT and basic data including the solution rate and the degree of the “Aha!” experience for each problem.

The Japanese version of the “Regret and Maximization Scale” (JRMS) can predict the individual difference in the style of decision-making. However, according to two previous studies that examined the reliability and validity of the JRMS, the reliability was not very high. In addition, the factor validity needs to be examined because the number of common factors the JRMS might consist of was ambiguous. The present study tested the factorial pattern of the JRMS using voluntary panel Web surveys. We conducted an exploratory factor analysis on 1,121 samples in Study 1 and a confirmatory factor analysis on 480 samples in Study 2. Both analyses showed that the JRMS consists of three factors: regret for one’s life, regret for purchase, and maximization. These results verified the factor validity of the JRMS. Each subscale showed an acceptable level of internal consistency. Each factor index positively correlated with each other, and also positively correlated with the age of participants. We discussed the reason why regret was divided into two categories, and the applicability of the JRMS to other studies.

Verbal descriptions of reinforcement contingencies (rules) often exert control over human behavior. The present study investigated how rules affected behaviors when two participants partially communicated with each other during an experiment. Mouse clicks by undergraduate students produced points depending on a multiple fixedratio 50 differential-reinforcement-of-low-rate 10-s schedule. During interruptions in the multiple schedules, participants were asked to describe the schedule contingencies, and then a speaker read the rules to one of a pair of participants (a listener). Discrimination ratios for the listeners were significantly higher than those for participants who were not asked to describe the rules or listened to other’s rules. When both schedules changed to fixedinterval 10-s, all groups were sensitive to schedule changes. The results suggest that the acquisition of scheduleappropriate behavior was affected by instructions even though the instructions were given by individuals other than the experimenter and were imperfect. The results also suggest that the effects of rules and self-rules can be replicated in two-person experiments.

This study investigated the processing and comprehension of thought questions typically used in the Japanese false-belief task. Word order variation in Japanese may affect processing and comprehension of thought questions, but there is no standardization for Japanese thought questions used in the false-belief task that examines children’s development of Theory of Mind. In this study, 30 adult participants were tested on five types of thought questions in an off-line judgment task and an on-line self-paced reading task. The results showed that there are indeed some differences in comprehension difficulties depending on word order for questions that express the same meaning. These results are discussed with regard to the syntactic properties of the question types and its implications for the assessment of children on the false-belief task.

Many previous studies have shown that visual memory plays an important role in change detection. Nishiyama & Kawaguchi (2014) focused on the visual long-term memory that was encoded before a change detection task, and they reported that the visual long-term memory affected the change detection performance. We investigated whether those results are reproducible. Participants performed two experiments consisting of a study phase, change detection phase, and indirect recognition phase (Nishiyama & Kawaguchi, 2014). They studied pre-change images of meaningless objects in both experiments. In Experiment 1, each image was studied five times, while in Experiment 2, each image was studied either five times or one time, and the change detection performance and results of the indirect recognition task were measured. The results of both experiments revealed that visual longterm memory could be retained in detail. However, these findings differed from those of Nishiyama & Kawaguchi (2014) and indicate the need for a more solid experimental procedure to clarify the effect of visual long-term memory on change detection.

This study explored the inhibitory effects of constituent kanji characters on the semantic processing of Japanese kanji words. We used a semantic categorization task in which participants judged whether words represented human entities (human words) or not (general words). Both types of words were composed of two kanji characters, and in half of the words, the second kanji character represented a human entity (human characters), while this was not the case in the other half. The mean semantic categorization time for general words with human characters was longer than it was for the other general words. Furthermore, the mean error rate for the former was higher than was that for the latter, indicating inhibitory effects of constituent kanji characters. However, the mean semantic categorization time and mean error rates for human words did not differ between those with and without human characters, indicating no facilitatory effects. Finally, a theory of semantic processing of Japanese kanji words explaining these results is proposed.