Dynamic phase-locking states and personality in sub-acute mild traumatic brain injury: An exploratory study

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Maladaptive personality traits, particularly Neuroticism, are linked to poorer outcomes following mild traumatic brain injury (mTBI).
• Understanding the neural mechanisms connecting personality and mTBI recovery is crucial for developing targeted interventions.

Purpose of the Study:

• To investigate the neural underpinnings of the relationship between personality and persistent symptoms after mTBI.
• To explore the role of dynamic functional network connectivity (dFNC) and diffusion MRI (dMRI) in mTBI outcomes.

Main Methods:

• Utilized resting-state fMRI (rs-fMRI) and dMRI in 27 mTBI patients and 21 healthy controls (HC).
• Assessed personality dimensions (Big Five) and symptom severity at six months post-injury.
• Employed principal component analysis (PCA) for personality factors and leading eigenvector dynamic analysis (LEiDA) for dFNC, alongside tract-based spatial statistics for dMRI.

Main Results:

• No significant differences in overall dFNC phase-locking states between mTBI patients and HC.
• A trend for decreased fractional anisotropy in mTBI patients, particularly in white matter tracts like the fornix and corpus callosum.
• One specific dFNC state, involving executive/saliency and default mode networks, was associated with lower symptom severity, an effect more pronounced in emotionally unstable patients.

Conclusions:

• Preliminary evidence suggests a coupling between personality (emotional instability) and dFNC in the development of long-term symptoms after mTBI.
• Specific dynamic brain network states may mediate the impact of personality on mTBI recovery.
• dMRI findings did not directly correlate with dynamic phase-locking states in this study.