Robin Edelstein, Ph.D., University of Michigan Psychology

Current Research Projects

Adult Attachment, Intimacy, and Hormones

Our research explores the biological correlates and consequences of individual differences in adult attachment. We are particularly interested in hormones linked with nurturance (e.g., estradiol, testosterone) and stress (e.g., cortisol). Estradiol, for instance, has been associated with bonding and caregiving in humans and other mammals, suggesting that it may be quite relevant to close relationships. Our work provides novel evidence that avoidant individuals have lower baseline estradiol levels (Edelstein, Stanton, Henderson, & Sanders, 2010), which may at least partially explain their difficulties with intimacy. In an experimental test of this idea, we found that emotionally intimate stimuli (but not other positive stimuli) elicited increases in estradiol; however, highly avoidant women did not show these effects (Edelstein, Kean, & Chopik, 2012). Our other ongoing projects explore the role of attachment in physiological and psychological responses to intimate relationship experiences, such as cuddling (van Anders, Edelstein, Wade, & Samples-Steele, 2013).

We are currently assessing attachment-related changes in hormones and adjustment among couples during the transition to parenthood. Expectant parents show many psychological and physiological changes during pregnancy and the postpartum, which may predict important postpartum outcomes (e.g., depression, marital satisfaction). Our preliminary findings suggest that women with an avoidant attachment orientation show larger prenatal increases in cortisol, an important stress hormone. Avoidant women also show larger prenatal increases in testosterone; our own and others’ research suggests that higher testosterone is associated with greater interest in extra-dyadic sexual activity and lower relationship satisfaction (e.g., Edelstein, Chopik, & Kean, 2011;Edelstein, van Anders, Chopik, Goldey, & Wardecker, in press).

Finally, we are investigating lifespan and longitudinal links between attachment and relationship processes to determine whether and how attachment orientations change with age and life experience (Chopik, Edelstein, & Fraley, 2013; Chopik & Edelstein, in press).

Testosterone and Relationship Processes

Although testosterone may promote the establishment of sexual relationships, high levels of testosterone may be associated with poorer functioning in ongoing romantic relationships. For instance, men and women in romantic relationships generally have lower testosterone than those who are single. However, our findings suggest that partnered men who report greater desire for uncommitted sexual activity have testosterone levels comparable to those of single men; partnered women who report more frequent uncommitted sexual behavior have testosterone levels comparable to those of single women (Edelstein et al., 2011). These findings provide new evidence that people’s orientations toward sexual relationships, in combination with their relationship status, are associated with individual differences in testosterone.

More recently, we examined dyadic associations between testosterone and romantic relationship quality (Edelstein et al., in press). Consistent with the idea that high levels of testosterone may be incompatible with relationship maintenance, we found that testosterone was negatively associated with relationship satisfaction and commitment in both men and women. Participants’ satisfaction and commitment were also negatively related to their partners’ levels of testosterone. Our findings provide some of the first evidence for dyadic associations between testosterone and relationship quality in couples, highlighting the importance of considering couples' interdependence in social neuroendocrine research.

Physiological Implications of Narcissistic Traits

Narcissists rely on a host of defensive strategies to maintain their overly positive self-images and high yet unstable self-esteem. Although reliance on defensive strategies has generally been associated with poor health outcomes, research on narcissism has largely ignored the physiological implications of this personality construct. In recent work, we have found that narcissism predicts increased cortisol reactivity, a marker of activity of a major stress response system, the hypothalamic pituitary (HPA) axis (Edelstein, Yim, & Quas, 2010). These findings suggest a possible pathway linking narcissistic traits with long-term health outcomes. Indeed, in longitudinal research, we have found that maladaptive aspects of narcissism predict poorer physical and mental health among women during midlife (Edelstein, Newton, & Stewart, 2012).

In future work, we plan to assess narcissism-health associations more directly. For instance, does narcissism predict day-to-day HPA reactivity, and do HPA responses predict long-term physical health outcomes for narcissistic individuals?