Altered connections on the road to psychopathy

Area of Science:

• Neuroscience
• Psychiatry
• Forensic Psychology

Background:

• Psychopathy is strongly associated with severe criminal behavior and recidivism.
• Previous research implicated amygdala and orbitofrontal cortex (OFC) dysfunction.
• The white matter connections, like the uncinate fasciculus (UF), linking these regions in psychopaths were unexamined.

Purpose of the Study:

• To investigate the microstructural integrity of the uncinate fasciculus (UF) in individuals with psychopathy.
• To explore the neurobiological basis of psychopathy by examining limbic network white matter connections.

Main Methods:

• Utilized in vivo diffusion tensor magnetic resonance imaging (DT-MRI) tractography.
• Analyzed the uncinate fasciculus (UF) in psychopaths (Psychopathy Checklist Revised (PCL-R) score ≥ 25) with severe criminal convictions.
• Compared findings with age- and IQ-matched healthy controls and psychiatric controls.

Main Results:

• Significantly reduced fractional anisotropy (FA), indicating lower microstructural integrity, was found in the UF of psychopaths.
• A correlation between antisocial behavior measures and UF anatomical differences was observed within the psychopathy group.
• No significant differences were found in control tracts, suggesting specificity to the amygdala-OFC network.

Conclusions:

• Abnormalities in the white matter connections of the amygdala-OFC limbic network, specifically the uncinate fasciculus (UF), underpin the neurobiological basis of psychopathy.
• Findings suggest a specific neural circuit dysfunction associated with psychopathic traits and severe antisocial behavior.