Neurogenetic Basis of Personality
Personality traits are influenced by genetic and environmental factors and are related to mental health. Previous neuroimaging studies have reported associations between personality and brain structure, while at the same time, studies on imaging genetics have repeatedly demonstrated heritability of brain structure. However, to date, it is unknown whether the association between personality and brain macrostructure can be explained by shared genetic factors. Here we report a large-scale twin study (Human Connectome Project), finding genetic correlation between personality traits and brain structure. Agreeableness was genetically correlated with the posterior-mid temporal, midcingulate, and dorsolateral frontal cortices, while extraversion showed a genetic relation to temporoparietal junction. Quantitative functional decoding indicated regions associated with personality are implicated in (socio-)cognitive and language processing. Last, assessment of genetic correlation of personality and adaptive behavior suggests overlapping neurogenetic substrates of personality and adaptive function and problems. Together, these observations provide first evidence of a direct genetic link between complex behavioral traits such as personality, local brain morphometry, and function of the respective brain regions.