Hypo-connected pattern in Parkinson's disease with pure apathy: A dynamic functional connectivity perspective

Area of Science:

• Neuroscience
• Neurology
• Brain Imaging

Background:

• Apathy is a common non-motor symptom in Parkinson's disease (PD).
• Understanding the brain network dynamics underlying apathy in PD is crucial.
• Previous research has not fully elucidated the dynamic functional network connectivity (dFNC) in patients with PD and pure apathy (PD-PA).

Purpose of the Study:

• To investigate the dynamic brain network changes associated with apathy in Parkinson's disease.
• To explore the functional connectivity patterns in the brains of patients with PD-PA using dFNC analysis.

Main Methods:

• Employed dynamic functional network connectivity (dFNC) analysis.
• Studied 30 patients with PD-PA, 37 patients with PD but not pure apathy (PD-NPA), and 37 healthy controls (HCs).
• Identified seven brain networks configured into four distinct states.

Main Results:

• Patients with PD-PA exhibited a longer mean dwell time in a hypo-connected state (State 1) compared to PD-NPA patients.
• The mean dwell time in State 1 positively correlated with apathy severity in PD-PA patients.
• Within State 1, decreased intra-network functional connectivity (FC) was observed in the default mode network (DMN) of PD-PA patients, specifically involving the left precuneus and left medial superior frontal gyrus (SFGmed).

Conclusions:

• Apathy in PD may stem from prolonged periods of low connectivity within brain networks.
• Impaired information transmission, particularly the disconnection between the precuneus and SFGmed within the DMN, is a key mechanism underlying apathy in PD.