Previous studies on adolescents’ interpersonal relationships have primarily focused on specific functions, such as support, or specific partners, such as mothers, leaving a gap in understanding daily interactions with close connections. This study included 801 individuals from 5th grade to university who responded to a mail or online survey depending on their age. Multivariate analysis of variance indicated that the importance of support from mothers and friends varied by the type of support required. Mothers often provided negative functions and became targets of arguments. Positive support tended to decrease with age, whereas self-disclosure in friendships increased. Girls tended to receive more support from their mothers and friends, whereas boys received more support from their fathers.

【Research Impact】

This study examines interpersonal relationships from adolescence to young adulthood, shedding light on the developmental shifts in close networks, offering insights into the interpersonal dynamics of Japanese youth in network functions. Additionally, the study introduces an assessment tool to evaluate interpersonal relationships, which will support developmental research and intervention practices.

Most people consider envy a negative emotion. However, envy can be either malicious or benign. Malicious envy motivates one to pull others down, whereas benign envy motivates one to improve themselves. Although preschoolers can understand envy from a third-party perspective, the behaviors elicited by their envy have not been studied. This study employed a within-subjects design; we set competitive situations in which six-year-olds (N=61) felt either malicious or benign envy after losing a competition. We examined the children’s liking for the competitor and their behaviors in response to malicious or benign envy. The results indicate that their liking for the competitor remained unchanged under the malicious envy condition, and they attempted to pull the competitor down. However, in the benign envy condition, the participants’ liking for the competitor increased and they did not attempt at pulling the competitor down. Moreover, regardless of the conditions, children worked harder on tasks. These findings indicate that children exhibit different behaviors even in their preschool years based on whether they have malicious or benign envy.

【Research Impact】

We analyzed whether malicious and benign envy induce different behaviors among 6-year-olds by creating a situation in which they lose to other children. In the malicious envy condition, the children prevented their competitor’s success. However, regardless of the conditions, the children displayed self-improvement behaviors, such as diligently working on tasks. This indicates that, even in preschool years, envy may affect children’s behavior.

This study investigated the effects of age differences in months on students’ cognitive development. First, we analyzed the data pertaining to the National Center Test (NCT) for University Admissions. It was found that the rate of those taking the NCT in the population was higher among those who were older in terms of months. However, the success rate on the exam was higher among younger test takers. Conversely, the percentage of those who completed schooling at public universities was lower among younger age groups. Next, we analyzed data from the 21st-Century Longitudinal Survey of Births. The results revealed that while younger children were at an academic disadvantage upon entering high school, they tended to acquire academic skills, surpassing those of their seniors during their three years of high school. However, developmental differences persist during high school entrance examinations; hence, the proportion of younger students pursuing higher education declines. Therefore, relative age effects potentially impact educational opportunities through entrance examinations during early schooling.

【Research Impact】

Relative younger children had relatively low academic achievement during high school entrance examinations. However, their academic achievement increased to a level surpassing that of their elders during their three years of high school. These results indicate that students are freed from the limitations of age-related developmental differences at the high school stage, and their latent ability and daily work lead to significant achievement.

This study investigates the perceptions of special needs education teachers in high school with regard to the transformative process of disability acceptance among students with mild intellectual disabilities (MID). Semi-structured interviews were conducted with 21 teachers, generating 47 cases. The study employed the modified grounded theory approach (M-GTA) for data analysis. The results indicated that teachers perceive disability acceptance as primarily comprising three key components: Recognition of personal limitations, utilization of institutional frameworks for individuals with disabilities, and acceptance of being categorized as having MID. Based on the cases, the findings revealed certain discrepancies regarding the degree of transformation among the aforementioned components. Additionally, a number of teachers critically perceived the concept of disability acceptance, expressed difficulty in determining whether or not students had accepted MID, and questioned the necessity of disability acceptance among students.

【Research Impact】

The first impact of this study lies in its empirical elucidation of the transformative process of disability acceptance among students with MID from the perspective of special needs education teachers. Previous scholars had only clinically discussed the process in special needs education. The second impact pertains to the identification of a new perspective on disability acceptance, that is, “respecting a way of life that does not involve disability acceptance.” Teachers frequently face the challenges of navigating between honoring the reluctance of students to accept MID and addressing the practical need for institutional support.