Longitudinal associations between the infant gut microbiome and negative affect in toddlerhood

Area of Science:

• Developmental psychology
• Microbiome research
• Pediatric health

Background:

• The gut microbiome's role in infant development and gut-brain connections is increasingly studied.
• Previous research suggests links between infant gut microbiome composition and temperament, like negative affect.
• Inconsistent findings across studies highlight the need for longitudinal research with varied assessment approaches.

Purpose of the Study:

• To investigate the longitudinal associations between the infant gut microbiome and negative affect.
• To examine how gut microbiome diversity and specific bacterial genera at different infant ages relate to later child behavior.
• To understand the impact of the timing of gut microbiome assessment on observed associations with negative affect.

Main Methods:

• A longitudinal study involving infants and caregivers.
• Gut microbiome composition assessed at two infant time points: 2 weeks and 18 months.
• Negative affect measured at 30 months of age.

Main Results:

• Higher gut microbiome diversity at 2 weeks of age was associated with increased observed negative affect at 30 months.
• Specific bacterial genera in the infant gut microbiome showed associations with negative affect.
• The timing of gut microbiome measurement influenced the observed associations with child behavior.

Conclusions:

• Infant gut microbiome diversity and composition are associated with later negative affect.
• The relationship between the gut microbiome and child behavior may be dependent on the developmental stage at which the microbiome is assessed.
• These findings underscore the dynamic interplay between the early-life gut microbiome and neurodevelopmental trajectories.