Increased Rostral Anterior Cingulate Cortex Volume in Chronic Primary Insomnia.

Area of Science:

• Neuroimaging
• Sleep Medicine
• Psychiatry

Background:

• Previous research suggests structural brain differences in individuals with chronic primary insomnia (PI).
• This study aimed to validate these findings in two independent PI cohorts.

Purpose of the Study:

• To confirm observations of altered brain volumes in PI patients.
• To investigate the relationship between rostral anterior cingulate cortex (rACC) volume and insomnia severity.

Main Methods:

• Two independent groups of unmedicated PI patients and healthy controls were compared.
• 3.0 T MRI was used to measure normalized rostral anterior cingulate cortex (rACC) volumes.
• Sleep diaries and wrist actigraphy were employed to assess sleep parameters.

Main Results:

• Both studies found significantly increased normalized rACC volumes in PI patients compared to controls.
• rACC volumes correlated with measures of insomnia severity, including sleep onset latency and sleep efficiency.

Conclusions:

• Patients with PI exhibit larger rostral anterior cingulate cortex (rACC) volumes.
• These findings suggest a potential compensatory brain response to chronic insomnia.
• rACC volume may serve as a biomarker for resilience to depressive illness.