Changes in electrophysiological aperiodic activity during cognitive control in Parkinson's disease

Area of Science:

• Neuroscience
• Cognitive Science
• Biomedical Engineering

Background:

• Cognitive impairment is a significant challenge in Parkinson's disease (PD).
• Aperiodic activity in electroencephalography (EEG) shows promise as a biomarker for various physiological and pathological states.
• Understanding EEG aperiodic activity in PD could reveal insights into cognitive decline.

Purpose of the Study:

• To investigate aperiodic EEG activity during cognitive control in Parkinson's disease patients.
• To determine if aperiodic EEG parameters correlate with behavioral performance and clinical features in PD.
• To explore the relationship between aperiodic activity, cognitive control, and arousal states in PD.

Main Methods:

• High-density EEG was recorded from 30 healthy controls and 30 PD patients during a Simon task.
• Task-related behavioral data were analyzed using the activation-suppression model.
• Aperiodic EEG parameters (offset, exponent) were extracted at scalp and source levels.

Main Results:

• PD patients exhibited poorer cognitive control performance and higher aperiodic offsets in parieto-occipital areas, indicative of increased neural excitability.
• Aperiodic parameters showed significant differences across resting-state, pre-stimulus, and post-stimulus phases, linked to task execution.
• No significant correlations were found between aperiodic EEG activity and behavioral performance or clinical PD features.

Conclusions:

• EEG aperiodic activity in PD is characterized by greater offsets, potentially reflecting increased neural excitability.
• Aperiodic parameters are sensitive to task execution and arousal states.
• The study did not find evidence supporting a direct link between aperiodic EEG changes and behavior-related differences in PD, warranting further investigation.