Altered cerebellar-cerebral functional connectivity in geriatric depression

Area of Science:

• Neuroscience
• Geriatric Psychiatry
• Cognitive Neurology

Background:

• Cerebellar volumetric and activation changes are noted in major depression.
• The cerebellum's precise role in depression's neural mechanisms is not fully understood.
• Investigating cerebellum-cerebral cortex functional connectivity offers insights into affective and cognitive dysfunction in depression.

Purpose of the Study:

• To examine resting-state functional connectivity between cerebellar regions and the cerebral cortex in geriatric depression.
• To determine the relationship between altered cerebellar connectivity and cognitive function and depression severity.

Main Methods:

• Seed-based connectivity analyses were performed using cerebellum regions from executive, default-mode, affective-limbic, and motor networks.
• Functional connectivity was compared between patients with geriatric depression (n=11) and healthy controls (n=18).
• Correlations between connectivity and cognitive tests (Hopkins Verbal Learning Test-Revised) and depression severity were assessed.

Main Results:

• Depressed individuals showed reduced functional connectivity between executive/affective-limbic cerebellum regions and the ventromedial prefrontal cortex (vmPFC).
• Increased functional connectivity was observed between motor-related cerebellum regions and the putamen/motor cortex in depressed patients.
• Crus II-vmPFC connectivity positively correlated with delayed memory recall; vermis-posterior cingulate cortex (PCC) connectivity positively correlated with depression severity.

Conclusions:

• Altered cerebellum-vmPFC coupling may be associated with cognitive deficits in geriatric depression.
• Cerebellum-PCC coupling might be implicated in emotion processing within this patient group.
• These findings highlight the cerebellum's potential role in the neural circuitry of geriatric depression.