title: Relationship disruption stress in human infants: a validation study with experimental and control groups.
abstract: The current study examined whether the psychological stress of the still-face (SF) task (i.e. stress resulting from a parent's unresponsiveness) is a valid laboratory stress paradigm for evaluating infant cortisol reactivity. Given that factors external to the experimental paradigm, such as arriving at a new place, may cause an elevation in cortisol secretion; we tested the hypothesis that infants would show a cortisol response to the SF task but not to a normal FF task (control). Saliva was collected for cortisol measurement from 6-month-old infants (n = 31) randomly assigned to either a repeated SF task or to a continuous FF task. Parent-infant dyads were videotaped. Salivary cortisol concentration was measured at baseline, 20, and 30 min after the start of the procedure. Infant salivary cortisol concentrations showed a significant increase over time for the SF task but not for the FF task. The results provide new evidence that the repeated SF task provides a psychological challenge that is due to the SF condition rather than to some non-task related factor; these results provide internal validity for the paradigm. The study offers new insight into the role of parent-infant interactions in the activation of the infant stress response system.
authors: Department of Psychology, University of Toronto, Toronto, ON, Canada. d.haley@utoronto.ca
authors: David W
authors: DW
authors: Haley
mesh_terms: D000339:Affect / Q000502:physiology; D005145:Face; D005260:Female; D005639:Frustration; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007223:Infant; D008297:Male; D009034:Mother-Child Relations; D012463:Saliva / Q000737:chemistry*; D013315:Stress, Psychological / Q000523:psychology*
chemical_list: D006854:Hydrocortisone