UCLA

Self-regulation requires bringing one’s thoughts, feelings, and behavior in line with one’s goals. Although this capacity is essential for social functioning, most studies have focused on processes within individuals. However, emerging theory and evidence indicate that self-regulation shapes the quality of people’s relationships, and conversely, people’s relationships affect the way they self-regulate. Across two studies, this dissertation investigated this reciprocal interplay. In addition, recent theories suggest that high-frequency heart rate variability (HF-HRV) may index self-regulation capacity and effort. In both studies, I assessed associations between HF-HRV and self-regulation, in order to test this biological marker. Study 1 tested how a self-control challenge affected the quality and consequences of couples’ interactions. Undergraduate couples (N = 148 individuals) were randomly assigned to sit with a bowl of cookies (or radishes, in the control condition), and not eat any. Afterwards, they discussed points of disagreement and appreciation in their relationship. The self-control challenge worsened couples’ interactions, as reflected in observer ratings of their behavior, self-reports of affect and attitudes, and a behavioral measure of aggression. Many of these effects were stronger for couples with lower relationship quality. Study 2 tested whether thinking of a supportive relationship (or an acquaintance, in the control condition) affected participants’ negative emotional responses, and their emotion regulation. Although we had a large sample (N = 206) and excellent statistical power, we found no evidence that prompting participants to think of a supportive relationship affected their emotional responses, or self-regulation. In both studies, we found little support for the hypothesized associations between HF-HRV and self-regulation.