Abstract
Multimodal studies evaluating associations of the Parkinson’s disease
(PD) specific neuroimaging and neurophysiological biomarkers in
revealing executive dysfunction mechanisms are scarce and needed to be
validated.
Hence, our study aimed to evaluate associations between
electroencephalographic power spectral density (PSD-EEG), striatal
[18F]Fluorodopa uptake and neuropsychological
cognitive testing parameters in PD. Additional aim was to estimate PD
diagnostic accuracy of the PSD-EEG parameters.
We compared resting PSD-EEG, striatal
[18F]Fluorodopa uptake ratio with positron
emission computed tomography ([18F]FDOPA PET/CT),
and neuropsychological test outcomes between PD patients and healthy
controls, and then calculated correlations among these outcomes.
Additionally we estimated PD diagnostic sensitivity and specificity
(with the receiver operating characteristic curves) of the PSD-EEG
parameters in reference to the gold diagnostic standard of the striatal
[18F]FDOPA PET/CT uptake ratio.
PD patients exhibited (i) increased power of the EEG theta and
lower-alpha bands in the frontal lobe areas, (ii) decreased putaminal
and caudate nuclei [18F]FDOPA PET/CT uptake and
(iii) longer performance times of part A and B of the Trail Making Test
(TMT-A and TMT-B). Most of the PSD-EEG parameters negatively correlated
with striatal [18F]FDOPA PET/CT uptake ratios and
positively correlated with TMT-A and TMT-B. Furthermore, striatal
[18F]FDOPA PET/CT uptake ratios positively
correlated with TMT-A and TMT-B. Theta and lower-alpha bands PSD-EEG
were found to have high diagnostic accuracy.
Our findings showed that slowing of EEG waves in the frontal lobe was
correlated with striatal dopaminergic deficiency and executive
dysfunction in mild PD patients, and appeared to be a promising
biomarker of PD-related executive dysfunction.
Key Words: Parkinson’s disease, executive dysfunction, EEG,
[18F]FDOPA PET/CT, cognitive impairment