Fatigue brain network functional connectivity in Parkinson's disease

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Fatigue significantly impacts Parkinson's disease (PD) patients' quality of life.
• The precise neural mechanisms underlying fatigue in PD remain unclear.
• Understanding the brain's functional connectivity (FC) in PD-related fatigue is crucial.

Purpose of the Study:

• To investigate the functional neural underpinnings of fatigue in Parkinson's disease.
• To examine the functional connectivity (FC) of the fatigue brain network in PD patients.
• To identify differences in brain network connectivity between PD patients with and without fatigue.

Main Methods:

• Resting-state functional magnetic resonance imaging (fMRI) was employed.
• Whole-brain analysis using the CONN Functional Connectivity Toolbox was performed.
• Forty-nine PD patients (fatigued and non-fatigued groups) and 33 healthy controls were recruited.

Main Results:

• PD patients with fatigue (PD-f) exhibited lower FC between the left dorsolateral prefrontal cortex and right accumbens (reward network).
• PD-f patients showed higher FC between the left insula and left posterior parahippocampal gyrus (interoceptive-paralimbic area) compared to PD patients without fatigue (PD-nf).
• Fatigue severity positively correlated with increased FC in the interoceptive-paralimbic network in PD patients.

Conclusions:

• Hypoactivation within the brain's reward network and hyperactivation in interoceptive-paralimbic areas may contribute to fatigue in Parkinson's disease.
• Functional connectivity alterations in these specific brain networks are associated with PD-related fatigue symptomatology.
• These findings enhance the understanding of the neural basis of fatigue in Parkinson's disease.