Intranasal oxytocin increases positive communication and reduces cortisol levels during couple conflict.
BACKGROUND
In nonhuman mammals, the neuropeptide oxytocin has repeatedly been shown to increase social approach behavior and pair bonding. In particular, central nervous oxytocin reduces behavioral and neuroendocrine responses to social stress and is suggested to mediate the rewarding aspects of attachment in highly social species. However, to date there have been no studies investigating the effects of central oxytocin mechanisms on behavior and physiology in human couple interaction.


METHODS
In a double-blind placebo-controlled design, 47 heterosexual couples (total n = 94) received oxytocin or placebo intranasally before a standard instructed couple conflict discussion in the laboratory. The conflict session was videotaped and coded for verbal and nonverbal interaction behavior (e.g., eye contact, nonverbal positive behavior, and self-disclosure). Salivary cortisol was repeatedly measured during the experiment.


RESULTS
Oxytocin significantly increased positive communication behavior in relation to negative behavior during the couple conflict discussion (F = 4.18, p = .047) and significantly reduced salivary cortisol levels after the conflict compared with placebo (F = 7.14, p = .011).


CONCLUSIONS
These results are in line with animal studies indicating that central oxytocin facilitates approach and pair bonding behavior. Our findings imply an involvement of oxytocin in couple interaction and close relationships in humans.
Ditzen
Beate
B
Department of Psychology, Clinical Psychology and Psychotherapy, University of Zurich, Zurich, Switzerland. b.ditzen@psychologie.uzh.ch
Schaer
Marcel
M
Gabriel
Barbara
B
Bodenmann
Guy
G
Ehlert
Ulrike
U
Heinrichs
Markus
M
D000281:Administration, Intranasal; D000328:Adult; D003142:Communication; D003220:Conflict, Psychological; D004311:Double-Blind Method; D005191:Family Characteristics; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D010121:Oxytocin / Q000008:administration & dosage*; D010919:Placebos; D012463:Saliva / Q000187:drug effects / Q000378:metabolism
D010919:Placebos; D010121:Oxytocin; D006854:Hydrocortisone