The nature of the relationships between personality and cognitive characteristics

In the current study we investigated the contribution of genetic and environmental factors to the relationship between the Big Five personality traits and nonverbal intelligence assessed with Raven’s Standard Progressive Matrices. The sample included a total of 290 people: 59 monozygotic (MZ) and 86 dizygotic (DZ, 58 same-sex and 28 opposite-sex) twin pairs aged 14 to 20 years (mean age = 15.84, SD = 1.05). The phenotypic correlations between the traits and intelligence scores were non-significant, except for Openness. This relationship was largely explained by shared environmental influences (65%)