Infant EEG profiles prospectively differentiate temperament and early mental health risk in childhood

Background: EEG provides a scalable method for elucidating neurophysiological characteristics that may distinguish mental health risk early in life, when symptoms are often non-specific, transdiagnostic, and pluripotential. Most prior studies have examined cross-sectional associations between individual EEG metrics and singular outcomes, potentially overlooking integrated patterns of neurophysiological organization. We applied data-driven clustering to infant baseline EEG to derive neurophysiological profiles and examined whether these profiles prospectively differentiated temperament and psychopathology domains in childhood. Methods: Participants were (N = 360; 46% female) from a longitudinal community cohort followed from infancy to age 7 years. Baseline EEG was collected in infancy (Mage = 7.81 months). Neurophysiological profiles were derived from spectral features (band-limited periodic power, peak frequency characteristics, and aperiodic exponent) using Bayesian model averaging of multiple clustering algorithms. Bayesian mixed-effects models tested profile differences in parent-reported temperament (surgency, negative affectivity, regulation/effortful control) across infancy and ages 3, 5, and 7 years, and child internalizing and externalizing symptoms at 5 and 7 years. Results: Consensus clustering identified four infant neurophysiological profiles characterized by: (1) elevated alpha/beta power, (2) low-frequency-dominant power, (3) globally attenuated oscillatory power, and (4) faster frequency-shifted dynamics. The profiles showed graded differentiation across childhood in effortful control (Cluster 1>2>3>4), with strong evidence for higher effortful control in Clusters 1/2 relative to Clusters 3/4 (posterior probabilities > .95). Additional differentiation was observed across surgency, negative affectivity, and psychopathology symptoms. Clusters 3/4 showed higher internalizing and externalizing symptom probabilities relative to Clusters 1/2, particularly Cluster 2, which also showed lower surgency relative to Clusters 1/3/4. Conclusions: Infant EEG-derived neurophysiological profiles prospectively differentiated temperament and psychopathology outcomes in childhood. With ongoing research, data-driven EEG profiling may provide a scalable, biologically informed framework for early mental health risk stratification prior to the consolidation of stable psychiatric diagnoses.