Decomposing the role of alpha oscillations during brain maturation

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Computational Neuroscience

Background:

• Childhood and adolescence are critical periods for neural reorganization.
• Alpha oscillations are a dominant feature of the human electroencephalogram (EEG) signal.
• Conventional EEG measures of alpha power are confounded and require decomposition into periodic and aperiodic components.

Purpose of the Study:

• To investigate how periodic and aperiodic components of alpha activity change during brain maturation.
• To clarify the relationship between distinct EEG signal components and neurodevelopmental processes.
• To re-evaluate previous interpretations of age-related changes in total alpha power.

Main Methods:

• Analysis of the largest openly available pediatric EEG dataset (N=2529, ages 5-22).
• Replication using a preregistered analysis of an independent validation sample (N=369, ages 6-22).
• Application of multivariate Bayesian generalized linear models to examine alpha activity parameters.

Main Results:

• Replicated the age-related decrease in total alpha power.
• Found strong evidence for an age-related increase in aperiodic-adjusted alpha power.
• Demonstrated that aperiodic intercept and slope decrease with age, correlating with total alpha power.

Conclusions:

• Age-related decreases in total alpha power may reflect synaptic elimination (aperiodic intercept changes).
• The maturational increase in aperiodic-adjusted alpha power is associated with enhanced thalamocortical connectivity.
• Increased thalamic control over cortical alpha power correlates with improved attentional performance during development.