Functional coherence of insula networks is associated with externalizing behavior

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Externalizing behaviors, including substance use and aggression, are linked to brain abnormalities.
• Recent research suggests the insula plays a role in these behaviors, challenging previous focus on the prefrontal cortex and amygdala.

Purpose of the Study:

• To investigate the relationship between insula functional coherence and externalizing behaviors in a large community sample.
• To determine if specific insula intrinsic connectivity networks (ICNs) are associated with different domains of externalizing psychopathology.

Main Methods:

• Resting-state functional MRI (fMRI) was used to assess brain activity in 244 community participants.
• Independent components analysis identified three insula-involved ICNs.
• Regression models examined the association between insula ICN coherence and externalizing domains measured by the Externalizing Spectrum Inventory.

Main Results:

• Posterior insula coherence positively correlated with general disinhibition and substance abuse.
• Anterior insula/ventral striatum/anterior cingulate network coherence negatively correlated with general disinhibition.
• Insula coherence did not show a significant relationship with callous aggression.

Conclusions:

• Insula network coherence is significantly associated with externalizing behaviors, particularly general disinhibition and substance abuse.
• The neural synchrony within insula networks appears central to understanding externalizing psychopathology.
• Specific insula ICNs demonstrate a unique relationship with externalizing behaviors compared to other frontal and limbic networks.