Abstract
Oxytocin facilitates pro-social behaviour and is proposed as a regulatory factor controlling stress reactivity. Previous research on oxytocin and stress has focused on achievement-related stressors among male participants. The aims of the study were to (1) examine the influence of oxytocin on the affective and cortisol response to the Yale Interpersonal Stressor (YIPS), a live social rejection paradigm, and (2) to replicate the finding that women exhibit a greater cortisol response to interpersonal stress than men (Stroud et al. 2002). Sex differences in stress responses: Social rejection versus achievement stress. Biol Psychiat 53:318–327. Ninety-six undergraduate students underwent the YIPS, where participants were excluded from two separate conversations by two same-sex confederates. Salivary cortisol concentrations and mood were repeatedly measured throughout the study. Participants were administered, in a double-blind design, a single dose of intranasal oxytocin (24 IU) or placebo prior to beginning the YIPS. The YIPS elicited a significant negative mood response that was more pronounced in females than in males. However, no significant cortisol response to the stressor and no sex difference in cortisol reactivity were observed. A significant effect of drug condition on cortisol levels was observed. Participants who were administered oxytocin exhibited a decrease in cortisol levels, relative to placebo, during the YIPS, F (4, 184) = 4.50, p < 0.05. The study failed to replicate the sex difference in the cortisol response to interpersonal stress reported by Stroud et al. (2002). Intranasal oxytocin, however, appeared to reduce cortisol concentrations during an interpersonal challenge.
Acknowledgements
Over the course of the research project, Anne-Marie Linnen was supported by a scholarship from les Fonds québécois de la recherche sur la nature et les technologies (FQRNT). Dr Ellenbogen is currently supported by a Canada Research Chair appointment from the Social Sciences and Humanities Research Council of Canada. We thank Claire-Dominique Walker at the Douglas Hospital Research Laboratories for conducting the cortisol assays. We thank Pfeiffer of America, and in particular Danielle Petrow, for generously supplying us with nasal spray bottles and pumps. We thank members of the Stress and Developmental Psychopathology Laboratory at Concordia University, supervised by Dr Ellenbogen, for their help on this research project. We would also like to thank Dustin Washburn, Cory Cooperman, Janet Kaldas, Brigitte Hanna and Anne-Sophie Ouellette for their work on this research project.
Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.