We systematically searched PubMed and ISI Web of Science for studies comparing resting-state CBF in persons with PD and HC using modalities including arterial spin labeling (ASL)-MRI, SPECT, and PET. We performed activation likelihood estimation (ALE) meta-analysis to identify the convergence of reported CBF abnormalities in PD tested against randomly distributed foci, corrected for multiple comparisons using family-wise error correction at the cluster level (cFWE). Then, we performed behavioral decoding of the resulting convergent clusters based on the NeuroSynth database.

Out of 1,847 records initially screened, 530 articles were selected for full-text review. Of these, 30 studies met the eligibility criteria and were included. We identified two convergent clusters with reduced CBF in PD compared to HC. The first cluster, located in the left middle frontal gyrus (Montreal Neurological Institute (MNI): -32, 8, 56; 392 mm³), is associated with cognitive functions such as working memory and reasoning. The second cluster, found in the cuneus, precuneus, and posterior cingulate cortex (MNI: -2, -68, 16; 984 mm³), is linked to sleep and mood functions.

Compared to HC, persons with PD had lower resting CBF in the left middle frontal gyrus and precuneus/poster cingulate cortex, which are associated with higher-level neuropsychiatric functions such as working memory, sleep regulation, and mood, which are clinically relevant non-motor manifestations of PD.