Differential spectral quantitative electroencephalography patterns between control and Parkinson's disease cohorts

Area of Science:

• Neuroscience and Neurology
• Biomarkers and Diagnostics

Background:

• Progressive Lewy-type synucleinopathy (LTS) is a primary driver of Parkinson's disease (PD) motor and non-motor symptom progression.
• Understanding cortical dysfunction in PD dementia (PD-D) requires characterizing quantitative electroencephalography (QEEG) abnormalities across the LTS spectrum.

Purpose of the Study:

• To characterize spectral QEEG abnormalities in autopsy-defined controls, incidental Lewy body disease (ILBD), and clinically defined PD groups (cognitively normal, mild cognitive impairment, PD-D).
• To investigate QEEG changes associated with cognitive decline in the Parkinson's disease spectrum.

Main Methods:

• Utilized an enlarged EEG database from the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND) longitudinal cohort.
• Analyzed resting electroencephalography (EEG) for spectral QEEG measures, including background rhythm frequency and global relative power in delta, theta, alpha, and beta bands.

Main Results:

• Spectral QEEG measures demonstrated differential changes specific to each group.
• Background rhythm frequency exhibited the most pairwise differences and was the sole significant differentiator between controls and ILBD.
• Increased delta band power correlated with worsening cognitive deficits.

Conclusions:

• QEEG patterns correlate with heterogeneous pathophysiologies of cortical dysfunction across the PD clinical spectrum.
• The utility of QEEG measures as biomarkers depends on their selective suitability for specific research objectives.