Maternal sensitivity and infant and mother adrenocortical function across challenges

Area of Science:

• Developmental Psychology
• Neuroendocrinology
• Maternal-Infant Interaction

Background:

• Previous research on maternal sensitivity and adrenocortical function (cortisol) in infants and mothers yielded inconsistent findings.
• The role of maternal sensitivity in infant cortisol variability across different challenges remains understudied.

Purpose of the Study:

• To investigate the relationship between maternal sensitivity and infant/mother cortisol levels and variability.
• To examine cortisol attunement between mothers and infants in relation to maternal sensitivity.

Main Methods:

• Assessed cortisol secretion in 297 infants and mothers across two challenges at 16-17 months.
• Conducted structured observations of maternal sensitivity at 16 months.
• Utilized multilevel modeling with an actor-partner interdependence model for data analysis.

Main Results:

• Maternal sensitivity correlated with infant cortisol levels and infant-mother cortisol attunement, but not maternal cortisol levels.
• Infants of more sensitive mothers exhibited greater cortisol variability across challenges compared to infants of less sensitive mothers.
• Mother-infant cortisol levels were highly correlated, with higher attunement observed in dyads with more sensitive mothers.

Conclusions:

• Maternal sensitivity is linked to infant cortisol regulation, specifically influencing cortisol variability across challenges.
• Higher cortisol response variability in infants of sensitive mothers may facilitate adaptation to stress while protecting against corticosteroid overexposure.
• Findings highlight nuanced maternal sensitivity effects on infant adrenocortical function and inter-individual cortisol patterns.