Properties of resting state functional connectivity associated with integrated combined subscales of Dark Triad

The neurobiological properties of the human brain associated with separate negative personality traits such as narcissism, psychopathy, and Machiavellianism, known as a Dark Triad (DT), have been extensively studied. However, their combinatorial properties have remained understudied in neuroimaging studies. To fill this gap, we performed a functional connectivity (FC) investigation of resting-state functional magnetic resonance imaging (rs-fMRI) for 129 healthy participants divided into two groups based on their profiles derived from the Dirty Dozen Dark Triad test using a clustering approach of k-means. The Variance Ratio Criterion was used to validate the optimal number of clusters. The seed-based analysis used regions of interest defined by the decrease in gray matter volume taken from a previous study. Individuals with Medium-to-High levels of Dark Triad (DT) prominence, compared to those with Low-to-Medium levels of DT, showed decreased functional connectivity between nodes of brain networks involved in emotion regulation, self-reference, and empathy. At the same time, high DT individuals demonstrated increased FC between regions involved in cognitive control and visual processing. Taken together, our findings suggest a specific and complex reconfiguration of large-scale brain networks in individuals with high DT traits rather than a generalized disruption of functional connectivity.