Abstract
Background: Slowing of the electroencephalogram (EEG) is frequent in Parkinson’s (PD) and Alzheimer’s disease (AD) and correlates with cognitive decline. As overlap pathology plays a role in the pathogenesis of dementia, it is likely that demented patients in PD show similar physiological alterations as in AD.Objective: To analyze distinctive quantitative EEG characteristics in early cognitive dysfunction in PD and AD.Methods: Forty patients (20 PD- and 20 AD patients with early cognitive impairment) and 20 normal controls (NC) were matched for gender, age, and education. Resting state EEG was recorded from 256 electrodes. Relative power spectra, median frequency (4–14 Hz), and neuropsychological outcome were compared between groups.Results: Relative theta power in left temporal region and median frequency separated the three groups significantly (p = 0.002 and p < 0.001). Relative theta power was increased and median frequency reduced in patients with both diseases compared to NC. Median frequency was higher in AD than in PD and classified groups significantly (p = 0.02).Conclusion: Increase of theta power in the left temporal region and a reduction of median frequency were associated with presence of AD or PD. PD patients are characterized by a pronounced slowing as compared to AD patients. Therefore, in both disorders EEG slowing might be a useful biomarker for beginning cognitive decline.
Highlights
Increase of theta power in the left temporal region and a reduction of median frequency were associated with presence of Alzheimer’s disease (AD) or PD
PD patients are characterized by a pronounced slowing as compared to AD patients.in both disorders EEG slowing might be a useful biomarker for beginning cognitive decline
Mild cognitive impairment (MCI) is a prodromal syndrome of neurodegenerative dementia without significant impairment in activities of daily living (ADL); it is unspecific as it can be caused by various pathologies (Winblad et al, 2004), and a considerable part of MCI patients remain stable or improve over time (Ritchie et al, 2001)
Summary
Mild cognitive impairment (MCI) is a prodromal syndrome of neurodegenerative dementia without significant impairment in activities of daily living (ADL); it is unspecific as it can be caused by various pathologies (Winblad et al, 2004), and a considerable part of MCI patients remain stable or improve over time (Ritchie et al, 2001). Comparison of AD and PDD patients with a similar degree of overt dementia showed more pronounced EEG slowing in PDD (Babiloni et al, 2011; Fonseca et al, 2013). It is unknown whether qEEG measures reliably discriminate between the two diseases at the beginning of the dementing process or whether they correlate with the extent of cognitive decline. Slowing of the electroencephalogram (EEG) is frequent in Parkinson’s (PD) and Alzheimer’s disease (AD) and correlates with cognitive decline. As overlap pathology plays a role in the pathogenesis of dementia, it is likely that demented patients in PD show similar physiological alterations as in AD
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
