Eysenck's biopsychological model of stress posits that the extraversion-introversion distinction is associated with different thresholds of arousal, which in turn moderate the stress response. Although higher thresholds of activation have been reported in the context of physiological stress induction, more contemporary research has resulted in mixed findings. The objective of the current study was to revisit Eysenck's biopsychological model of stress by examining associations between the two personality dimensions (extraversion-introversion and neuroticism-stability) and stress reactivity in response to the Trier Social Stress Test. A total of 122 participants aged 18 to 80 years were recruited. Participants completed a battery of questionnaires, including a personality questionnaire, and were exposed to the TSST, during which salivary cortisol and galvanic skin responses (GSR) were recorded. People scoring higher on extraversion displayed heightened GSR relative to people scoring lower on extraversion. Furthermore, sex-based analyses suggest that this association was driven by females. No significant associations were found for cortisol or with respect to the neuroticism-stability dimension of personality. These findings highlight the need to take a more nuanced approach to investigating the association between personality and stress reactivity, highlighting the importance of the stress induction protocol and the stress-sensitive system under investigation.
Keywords: Trier Social Stress Test; extraversion; neuroticism; personality; stress reactivity.