Lower aperiodic EEG activity is associated with reduced verbal fluency performance across adulthood

Area of Science:

• Neuroscience
• Cognitive Science
• Signal Processing

Background:

• Previous research on electroencephalography (EEG) and aging focused on periodic activity.
• EEG's aperiodic activity, characterized by exponent and offset, is understudied in cognitive aging.

Purpose of the Study:

• To investigate the association between resting-state EEG aperiodic activity (exponent and offset) and cognitive performance in healthy adults.
• To explore how these associations interact with age.

Main Methods:

• Secondary analysis of 111 healthy participants (aged 17-71).
• Resting-state eyes-closed EEG data analyzed for aperiodic exponent and offset.
• Principal Component Analysis and K-Means Clustering for electrode activity.
• Robust linear models to assess age interactions with aperiodic activity and cognitive tests (including Verbal Fluency Test).

Main Results:

• Identified electrode clusters with similar aperiodic exponent and offset.
• Found significant age interactions for aperiodic offset and Verbal Fluency Test performance.
• Smaller aperiodic offsets correlated with poorer verbal fluency in adults from age 33 onwards.
• Greater aperiodic activity showed increasing association with better verbal fluency as adults aged.

Conclusions:

• Aperiodic EEG activity, specifically its offset, is a significant correlate of cognitive function, particularly verbal fluency, across adulthood.
• These findings highlight the importance of considering aperiodic EEG signals for understanding cognitive aging.
• Aperiodic EEG may serve as a sensitive biomarker for early age-related changes in cognitive function.