Network alterations underlying anxiety symptoms in early multiple sclerosis

Area of Science:

• Neuroscience
• Neurology
• Psychiatry

Background:

• Anxiety is a common comorbidity in multiple sclerosis (MS), significantly impacting disease burden.
• Understanding the neurobiological underpinnings of anxiety in MS is crucial for patient care.

Purpose of the Study:

• To identify brain networks functionally connected to atrophied regions associated with anxiety in MS patients.
• To explore the relationship between structural brain changes and anxiety symptoms in MS.

Main Methods:

• Utilized 3-Tesla MRI to generate anxiety-related atrophy maps by correlating cortical thinning with anxiety severity in MS.
• Applied atrophy network mapping and seed-based functional connectivity analysis on a large normative connectome.
• Investigated neural excitability and effective connectivity using transcranial magnetic stimulation and high-density electroencephalography.

Main Results:

• Left dorsal prefrontal cortex thinning correlated with higher anxiety levels in MS patients.
• Atrophy network mapping revealed functional involvement of the prefrontal cortex, amygdala, and hippocampus.
• Structural equation modeling confirmed these regions' influence on anxiety symptoms; reduced prefrontal-amygdala information flow and increased prefrontal excitability were observed.

Conclusions:

• Anxiety in MS is associated with prefrontal cortical atrophy and specific network alterations resembling known anxiety circuits.
• These findings illuminate the role of anxiety in MS pathology.
• The results may pave the way for targeted therapeutic strategies modulating brain networks in MS.