Deviation from typical brain activity during naturalistic stimulation predicts personality traits

The relationship between personality and brain activity has been an increasingly popular topic of neuroscientific research. However, the limitations of both personality measures and neu-roimaging, as well as methodological issues, continue to pose challenges to its understanding. The naturalistic viewing condition has been shown to enhance individual differences and might, therefore, be of benefit to the endeavor. Here, we thus examine this relationship using naturalistic fMRI of 82 healthy subjects. We implemented a simple dimensionality reduction method to characterize brain activity by its ‘typicality’, assessed a range of personality traits using widely-used personality inventories, and tested the relationship between the two. We found that there is, indeed, a relationship between personality traits and the typicality of brain activity, most consistently manifested by lower typicality in subjects with higher Neuroticism/Harm Avoidance. Our results highlight the usefulness of naturalistic viewing data for exploring the relationship between individual differences in personality and brain activity.