Elevated caudate connectivity in cognitively normal Parkinson's disease patients

Area of Science:

• Neuroscience
• Neurology
• Cognitive Science

Background:

• Mild cognitive impairment (MCI) is prevalent in Parkinson's disease (PD), yet its mechanisms remain unclear, impeding targeted treatments.
• Understanding cognitive changes in PD is crucial for developing effective interventions and improving patient outcomes.

Purpose of the Study:

• To investigate functional connectivity alterations in the caudate nucleus of Parkinson's disease patients with varying cognitive statuses.
• To explore the relationship between caudate nucleus connectivity, cognitive function (Montreal Cognitive Assessment scores), and Alzheimer's disease-like patterns in PD.

Main Methods:

• Recruited 18 Parkinson's disease patients (10 normal cognition - PDNC, 8 low cognition - PDLC) and 10 healthy controls.
• Utilized resting-state functional magnetic resonance imaging (fMRI) and perfusion MRI for data acquisition.
• Analyzed fMRI data using graph theory metrics and perfusion MRI for Alzheimer's disease-like pattern scores.

Main Results:

• A significant positive correlation was observed between right caudate nucleus functional connectivity and Montreal Cognitive Assessment (MoCA) scores in PD patients.
• Parkinson's disease patients with normal cognition (PDNC) exhibited significantly higher right caudate connectivity compared to both low cognition PD (PDLC) and healthy controls.
• Alzheimer's disease-like metabolic/perfusion patterns correlated with MoCA scores in healthy controls, but not in PD patients.

Conclusions:

• Increased functional connectivity of the right caudate nucleus may represent a compensatory mechanism in cognitively normal Parkinson's disease patients.
• These findings support the dual syndrome hypothesis and highlight the caudate nucleus's role in maintaining cognitive function in early PD.
• Further research into caudate nucleus function could lead to novel therapeutic strategies for MCI in Parkinson's disease.