Neural Fingerprint of the Dark Triad: Resting State Functional
Connectivity Alterations in Executive and Default Mode Networks
Abstract
The neural foundations of the Dark Triad (DT) personality
traits—narcissism, Machiavellianism, and psychopathy—remain largely
unexplored despite their profound impact on social behavior. Previous
research has indicated potential structural and functional alterations
in the default mode network (DMN) and reward-related regions in
individuals exhibiting high levels of DT traits. However, these studies
have often been limited by univariate analytical methods and small,
unbalanced sample sizes. To address these gaps, we analyzed brain scans
from a robust sample of 200 participants (mean age: 32.43 years; 105
females) using group Independent Component Analysis (gICA), an
unsupervised machine learning approach. This method allowed us to
extract temporal variability associated with resting-state
macro-networks without relying on predefined regions of interest. Our
analysis identified 20 macro-networks, of which two were significantly
predictive of DT traits: the Central Executive Network (CEN) and the
posterior hub of the Default Mode Network (DMN). Notably, higher DT
scores correlated with increased blood-oxygen-level-dependent (BOLD)
temporal variability within the CEN and decreased variability within the
DMN. The heightened activity in the CEN may reflect enhanced
manipulative abilities and strategic planning commonly observed in
individuals with high DT traits, which is supported by the association
between the CEN and the Machiavellianism subscale. Conversely, reduced
functionality in the DMN may correspond to diminished self-reflective
and emotional capacities in these individuals. These findings contribute
to a deeper understanding of the neurobiological basis of DT traits and
hold implications for future research and interventions.