Attachment, depression, and cortisol: Deviant patterns in insecure-resistant and disorganized infants.

Both attachment insecurity and maternal depression are thought to affect infants' emotional and physiological regulation. In the current study, Strange Situation Procedure (SSP) attachment classifications, and cortisol stress reactivity and diurnal rhythm were assessed at 14 months in a prospective cohort study of 369 mother-infant dyads. Maternal lifetime depression was diagnosed prenatally using the Composite International Diagnostic Interview (CIDI). Insecure-resistant infants showed the largest increase in cortisol levels from pre- to post-SSP; the effect was even stronger when they had depressive mothers. Disorganized children showed a more flattened diurnal cortisol pattern compared to nondisorganized children. Findings are discussed from the perspective of a cumulative risk model.