Publication Date



Open access

Embargo Period


Degree Name

Master of Science (MS)


Psychology (Arts and Sciences)

Date of Defense


First Committee Member

Youngmee Kim

Second Committee Member

Michael H. Antoni

Third Committee Member

Armando Mendez


In moments of stress, adults often turn to their romantic partners as regulatory agents. Literature suggests that qualities of one’s relationship to their romantic partner will influence the magnitude of one’s physiological activation during moments of stress. Both attachment theory and findings to date suggest that insecure attachment is predictive of greater reactivity to stress. Moreover, whether the HPA-axis activity of a romantic partner - versus that of a stranger - who is present influences one’s physiological arousal during moments of acute stress, called coregulation, is largely unknown. This study tested the effects of physiological coregulation in romantic partners using a repeated-measures design with four samplings of salivary cortisol as outcome and one between-group factor (pairing of partner) to determine whether one’s HPA-regulated acute stress response is in part dependent on that of their romantic partner. The present study recruited young dating couples (N=40; Mean age=23; Mean relationship length=2 years; 48% Hispanic) from the University of Miami who provided valid data including demographic and physiological data. Participants were randomized into two group conditions: couple (paired with romantic partner) or stranger (paired with a study confederate). The experimental stress task asked participants to respond to a scenario wherein romantic partner was experiencing acute physical pain. Attachment (Measure of Attachment Qualities) and demographic data was collected before stress task. Salivary cortisol was sampled before stressor task onset (T1), immediately after 5-minute stress task (T2), and at eight (T3) and 18 minutes (T4) after. It was hypothesized that H1a) higher cortisol levels at T3 than T2 (controlling for T1) will be positively associated with attachment anxiety, followed by attachment avoidance, then attachment security; H1b) attachment avoidance scores would be associated with highest cortisol levels at T4, followed by attachment security, and then attachment anxiety; H2a) cortisol levels at T3 would be predicted by partners’ cortisol levels at T2, but only when paired with romantic partner (versus stranger); H2b) cortisol levels at T4 would be predicted by partners’ cortisol levels at T3, but only when paired with romantic partner (versus stranger); H2c) the influence of partner’s prior cortisol levels on one’s cortisol levels would be strongest when paired with romantic partner (versus stranger) and when one is high in attachment anxiety, followed by security, then avoidance. Overall, participants were relatively high in attachment security (M=3.79, SD=.40) and low in attachment avoidance (M=1.50, SD=.44) and attachment anxiety (M=1.50, SD=.49). General linear modeling indicated that participants’ cortisol levels increased during the stress task and decreased after cessation, F(1,39)=15.20, p <.001. A series of hierarchical linear regression models were conducted to test study hypotheses, controlling for relevant covariates such as age, gender, and time of day. Overall, none of the hypotheses were empirically supported. Results fail to relate individual cortisol levels during acute stress to their attachment to romantic partner or the cortisol levels of their study partner. Future studies would benefit from a larger sample size and adding measurements of cortisol at 10, 20, 30, 45, 60, 90, and 120 minutes after cessation of stress task in order to ensure reactivity and recovery processes are captured.


Coregulation; Cortisol; Attachment; Couples; Acute Stress