بررسی اثرناپذیری طرد اجتماعی بر ترشح کورتیزول بزاق در زنان در یک مطالعه کنترل شده تصادفی

Lack of social support and social exclusion are associated with adverse effects for mental and physical health. Additionally, women appear to be more vulnerable to social triggers of health disturbances. Activity of the hypothalamus–pituitary–adrenal-axis (HPA-axis) might play a key role in this context as it has been shown both to be associated with psychosocial conditions and health outcomes and to respond differentially depending on gender. To test this hypothesis we thus investigated the effects of social exclusion on cortisol release in women. To experimentally vary social exclusion we employed a highly standardized paradigm (Cyberball) which already has been shown to affect subjective well-being and some physiological parameters. Methods Healthy women (n = 89) were randomly assigned to one of the three Cyberball conditions: social exclusion, inclusion and technical default, respectively. Salivary cortisol and subjective mood were assessed as primary outcome variables immediately prior to and every 15 min after Cyberball. Results Social exclusion had no effect on cortisol secretion though significant effects on mood were observed. Conclusions These results indicate that the Cyberball social exclusion paradigm alone though affecting psychological well-being does not affect HPA-axis functioning.

Women are considered to be especially vulnerable to social triggers of health disturbances (Denton et al., 2004). One social trigger often analysed is the lack of social support and social exclusion (Hawthorne, 2008). Mechanisms mediating between the degree of social integration and physical and mental health are only partially understood. A potential mediator could be a dysregulation of HPA-axis functioning which is both known to be related to health disturbances and to social stress. Indeed, correlative research indicates that lack of social support is associated with an increased basal cortisol secretion (Cacioppo et al., 2000, Gunnar et al., 2003 and Evolahti et al., 2006). Correlative studies are, however, ambiguous with respect to causal inferences. Thus, experimental research is needed to examine the effects of social exclusion on cortisol secretion. Experimental research on social exclusion, however, faces the problem of how to induce a standardized social exclusion condition. “Cyberball,” a virtual ball game, represents one possibility of inducing social exclusion in a highly standardized manner (Williams et al., 2000). In this paradigm, participants are made to believe that they are playing with three other participants (which in fact are computer generated). During the game the degree of social inclusion (i.e., how often they receive the ball from the other participants) is manipulated: “included” participants receive the ball regularly throughout the game while “excluded” participants receive no further ball after the first throws. Previous research on this paradigm indicates that excluded participants not only perceive themselves as being excluded but also suffer from lower self-esteem compared to the included participants (Williams et al., 2000). Furthermore, fMRI studies have shown that the dorsal anterior cingulate cortex, a region also activated while experiencing physical pain, is activated during exclusion (Eisenberger et al., 2003). Effects of Cyberball on cortisol secretion have not been analysed, yet. We therefore used the Cyberball paradigm to assess the effects of social exclusion on HPA functioning and mood in a randomized controlled study. We expected both an increase of cortisol secretion after social exclusion and an increase of bad mood.