In order to clarify the influences of family environment on the development
of personality traits, 150 children (104 males and 46 females, mean age 13
.2+/-2.4 years) who had been interviewed at the Child Guidance Clinic in Os
aka were investigated. From 13 behavioral characteristics (activity, talkat
iveness, sociability, social skills, rule-keeping, will, aggression, emotio
nal control, imagination, anxiety, maturity, intelligence, and neuroticism)
, factor analysis identified three personality traits: extraversion, maturi
ty: and intellect. The effects of family environment (maternal and paternal
participation in child rearing before and after 4 years of age, child-rear
ing style, parental relationship, sibling relationship, number of siblings,
birth order, and socioeconomic status) on these personality traits were ex
amined based on a structural equation model. The results found, first, that
extraversion was negatively associated with overprotection/interference an
d with maternal participation in child rearing. Maturity correlated with hi
gh socioeconomic status, appropriate child-rearing style, and paternal part
icipation in child rearing. Intellect was related to high socioeconomic sta
tus and maternal participation in child rearing. Second, path analysis with
selected variables revealed that 8% of variance in extraversion, 14% iri m
aturity, and 10% in intellect was due to family environment. Third, childre
n with high introversion or high intellect had stronger influences from fam
ily environment than did those with high extraversion or low intellect.