Neuroanatomical Correlates of Extraversion and Neuroticism

TLDR

Extraversion, introversion, and neuroticism are key personality dimensions linked to emotional responses and psychiatric risk, and neuroimaging has identified specific functional and structural correlates in the prefrontal cortex and amygdala. The study aimed to examine structural correlates of neuroticism and extraversion in healthy adults using cortical thickness and amygdala volume measures. The authors assessed 28 healthy subjects, measuring cortical thickness in selected prefrontal regions and amygdala volume to investigate associations with personality traits. Cortical thickness in specific prefrontal regions correlated with extraversion and neuroticism, whereas amygdala volume showed no such association, indicating that particular prefrontal anatomical features are linked to these personality traits.

Abstract

Introversion/extraversion and neuroticism are 2 important and frequently studied dimensions of human personality. These dimensions describe individual differences in emotional responding across a range of situations and may contribute to a predisposition for psychiatric disorders. Recent neuroimaging research has begun to provide evidence that neuroticism and introversion/extraversion have specific functional and structural neural correlates. Previous studies in healthy adults have reported an association between neuroticism, introversion/extraversion, and the activity of the prefrontal cortex and amygdala. Studies of individuals with psychopathological states have also indicated that anatomic variations in these brain areas may relate to extraversion and neuroticism. The purpose of the present study was to examine selected structural correlates of neuroticism and extraversion in healthy subjects (n = 28) using neuroanatomic measures of the cerebral cortex and amygdala. We observed that the thickness of specific prefrontal cortex regions correlates with measures of extraversion and neuroticism. In contrast, no such correlations were observed for the volume of the amygdala. The results suggest that specific aspects of regional prefrontal anatomy are associated with specific personality traits.