Functional connectivity density abnormalities and anxiety in primary insomnia patients

Area of Science:

• Neuroscience
• Psychiatry
• Sleep Medicine

Background:

• Primary insomnia (PI) is linked to emotional dysregulation, but its neurobiological underpinnings are not fully understood.
• Previous research suggests PI impacts emotional regulation, yet specificity requires further investigation.

Purpose of the Study:

• To investigate the neurobiological basis of emotional dysregulation in primary insomnia.
• To determine if functional connectivity density (FCD) abnormalities in primary insomnia patients can serve as biomarkers for emotional states, specifically anxiety and depression.

Main Methods:

• Recruited 27 primary insomnia patients (PIs) and 32 healthy controls (HCs).
• Assessed spontaneous functional brain organization using functional connectivity density (FCD).
• Analyzed local FCD (lFCD) and global FCD (gFCD) in relation to emotional levels and insomnia severity.

Main Results:

• PIs reported higher anxiety and depression levels, correlated with insomnia severity.
• PIs demonstrated reduced lFCD and gFCD in the thalamus, anterior cingulate cortex (ACC), and insula.
• Lower gFCD in the left ACC and right insula was associated with anxiety levels in PIs, indicating potential biomarker utility.

Conclusions:

• Functional brain organization, specifically gFCD in the ACC and insula, is altered in primary insomnia patients.
• Reduced gFCD in these regions may act as a biomarker for anxiety in PIs.
• Insomnia severity and anxiety levels in PIs are partially mediated by gFCD in the ACC and insula, offering insights for therapeutic development.