Comparison of fALFF between three cognitive groups. (A) Without adjusting for confounding factors, brain regions with differences in fALFF among three cognitive groups included Midbrain, Limbic Lobe, Parahippocampal Gyrus, Brainstem, Brodmann area 34, Amygdala, Frontal Lobe. (B) After adjusting for confounding factors, brain regions with differences in fALFF among three cognitive groups included Midbrain, Brainstem, Parahippocampal Gyrus, Limbic Lobe, Amygdala, Brodmann area 34, and Frontal Lobe. brain regions among the three cognitive groups were basically the same, whether the confounding factors were adjusted or not. (C, F) There was no statistically significant difference in fALFF between PD patients with MCI and NC, regardless of adjustment for confounding factors. (D) Comparing PD patients with SCI and NC, without adjusting for confounding factors, there were differences in fALFF including Brainstem, Midbrain, Parahippocampal Gyrus, Brodmann area 34, Limbic Lobe, Mammillary body, Hippocampus, Occipital Lobe, Precuneus, Frontal Lobe, Brodmann area 4, Paracentral Lobule, Postcentral Gyrus. (G) Comparing PD patients with SCI and NC, after adjusting for confounding factors, there were differences in fALFF including Brainstem, Midbrain, Parahippocampal Gyrus, Limbic Lobe, Brodmann area 34, Occipital Lobe. (E) Comparing PD patients with SCI and MCI, without adjusting for confounding factors, there were differences in fALFF including Parahippocampal Gyrus, Limbic Lobe, Midbrain, Brodmann area 34, Brainstem, Amygdala, Frontal Lobe, Hippocampus, Precuneus, Brodmann area 31, Posterior Cingulate, Brodmann area 7. (H) Comparing PD patients with SCI and MCI, after adjusting for confounding factors, there were differences in fALFF including Midbrain, Brainstem, Limbic Lobe, Parahippocampal Gyrus, Brodmann area 34, Precuneus, Calcarine, Brodmann area 31, Occipital Lobe, Posterior Cingulate, Precentral Gyrus, Frontal Lobe.