Longitudinal changes in infant attention-related brain networks and fearful temperament.

Background: Anxiety disorders may partly stem from altered neurodevelopment of attention-related networks. Neonatal alterations in resting-state functional connectivity (rsFC) among the dorsal attention (DAN); frontal parietal (FPN); salience (SN); and default mode networks (DMN)) relate to fearful temperament, a risk marker for anxiety. Nevertheless, little research examines development of these networks beyond the first months of life, particularly in fearful infants. This study examines how changes in these networks in the first two years of life relate to fearful temperament.

Methods: Using data from the Baby Connectome Project (from 180 infants across 396 sessions), we conducted independent components analysis to extract rsFC among the DMN, SN, DAN, and FPN. Longitudinal modeling characterized 1) age-related changes (slope) in rsFC through age two; 2) relations between rsFC change (slope) and fearfulness at age 2; 3) relations between rsFC and fearfulness trajectories (slope and intercept) over the first two years of life.

Results: Age-related decreases occurred in rsFC in DAN - FPN and DMN - SN. Smaller decreases in DAN - FPN rsFC over time related to greater fear at age 2, and to increases in fearfulness over time. High initial DAN-FPN rsFC and low initial DAN - SN rsFC also related to increasing fearfulness over time.

Conclusion: This study provides the first evidence that changes in attention-related brain networks are related to early-life fearfulness, a robust early-life risk marker of anxiety.