Functional brain changes in Parkinson's disease: a whole brain ALE study.

Area of Science:

• Neuroscience
• Radiology
• Medical Imaging

Background:

• Resting-state functional magnetic resonance imaging (rs-fMRI) is a valuable tool for diagnosing neurodegenerative diseases.
• Previous rs-fMRI studies have yielded inconsistent findings when comparing Parkinson's disease (PD) patients with healthy controls (HC).

Purpose of the Study:

• To conduct a meta-analysis of activation likelihood estimation (ALE) to identify consistent functional brain changes in PD.
• To clarify discrepancies in prior rs-fMRI findings for PD.

Main Methods:

• A systematic literature search was performed across PubMed, Web of Science, and Google Scholar for studies published before December 2021.
• Activation Likelihood Estimation (ALE) meta-analysis was employed to synthesize functional changes observed in PD patients.

Main Results:

• The meta-analysis included 25 studies with 973 PD patients and 766 HC.
• PD patients exhibited altered amplitude of low-frequency fluctuations (ALFF) in regions including the superior temporal gyrus, superior frontal gyrus, medial frontal gyrus, precuneus, and lentiform nucleus.
• Reduced regional homogeneity (ReHo) was observed in the declive, medial frontal gyrus, culmen, and thalamus, while increased ReHo was found in the right superior frontal gyrus.
• Decreased functional connectivity (FC) was noted in the right posterior cingulate cortex in PD patients compared to HC.

Conclusions:

• The ALE meta-analysis confirms significant functional brain deficits in motor, emotion, and cognition-related areas in PD.
• These identified rs-fMRI functional deficits may serve as biomarkers for the early diagnosis of PD.