Individual differences in stress physiology : understanding person by situation influences

textDo person by situation effects influence physiological stress response? Despite being relatively uncontested since being theorized nearly 80 years ago, the fight-or-flight model of stress response has suffered criticism for its one-size-fits-all approach in light of the historical gender bias in the literature. In contrast, the tend-and-befriend model of stress response argues that females are driven to care for their offspring (tend) and band together with others (befriend) in response to stress. Despite evidence suggesting the importance individual differences in the effect of affiliation and social support on stress, past research has generally overlooked markers of individual difference and personality. The major aim of this dissertation was to identify and examine potential person by situation effects on stress physiology, illuminating under what conditions and for whom affiliation and social support may buffer against the stress response and aid recovery in the wake of a stressor. Two studies were conducted to evaluate the role of individual difference factors of gender and personality (i.e., person effects) and the availability of affiliation with a similar other (study 1) or a trusted friend (study 2) compared with no available affiliation (i.e., social situation effects) on stress response and recovery. Study 1 revealed that availability of affiliation with a similar other did not have a protective influence on stress physiology in general. However, personality (openness to experience) and gender together, along with availability of affiliation, were important predictors of stress physiology over time. Study 2 indicated that the availability of affiliation with a trusted friend had a protective effect on stress physiology across each time point. Further, extraversion, conscientiousness, and openness to experience each appear to be important predictors of the influence of availability of affiliation with a close friend on stress physiology over time. In sum, this dissertation found evidence of person by situation effects on stress physiology across two studies. In both studies, the effect of the availability of affiliation differed based on individual difference factors of personality, not on gender. As such, tend-and-befriend may be better conceptualized not as a uniquely female response, but rather a stress response that depends on individual difference characteristics of personality. Further, future stress response models and research should consider personality as an important marker of individual difference in physiological stress response.Psycholog