Borderline Personality Traits Are Not Correlated With Brain Structure in Two Large Samples

Area of Science:

• Neuroimaging
• Psychiatry
• Genetics

Background:

• Borderline personality disorder (BPD) is linked to severe psychiatric issues and brain structure variations.
• Dimensional models of borderline personality traits (BPTs) are influential, but their brain structure associations are unclear.

Purpose of the Study:

• To investigate the association between borderline personality traits (BPTs) and brain structure metrics.
• To validate findings using positive control analyses with related behaviors and experiences.

Main Methods:

• Examined regional cortical thickness, cortical surface area, and subcortical volumes in 1299 Duke Neurogenetics Study participants and 1099 Human Connectome Project participants.
• Conducted positive control analyses linking BPTs to suicidal behaviors, psychiatric diagnoses, and adverse childhood experiences.

Main Results:

• Borderline personality traits (BPTs) were robustly associated with all positive control behavioral measures.
• No significant associations were found between BPTs and any brain structure metrics across both datasets or in a meta-analysis.
• Weak, uncorrected associations between BPTs and left ventral diencephalon/thalamus volumes did not survive false discovery rate correction.

Conclusions:

• Replicable evidence indicates no association between borderline personality traits (BPTs) and measured brain structure.
• Previous links between brain morphology and BPD may stem from confounding factors like severity, comorbidities, or childhood adversity.
• Future research requires larger sample sizes to detect potential subtle effects of BPTs on brain structure.