This Psychology Today blog post is phase three of a nine-part series called "The Vagus Nerve Survival Guide." The nine vagal maneuvers featured in each of these blog posts are designed to help you stimulate your vagus nerve—which can reduce stress, anxiety, anger, and inflammation by activating the "relaxation response" mechanisms of your parasympathetic nervous system.
Face-to-face social connectedness fortifies the "tend-and-befriend" parasympathetic response and engages your vagus nerve. This improves vagal tone and counteracts stress responses associated with "fight-or-flight" mechanisms. Social connectedness has also been clinically proven to improve heart rate variability (HRV), which is the measurement of variations within beat-to-beat intervals and indicates a healthy heart.
As I described in the introduction to this series, your vagus nerve is the prime driving force of the parasympathetic nervous system which regulates your “rest-and-digest” or “tend-and-befriend” responses. On the flip side, to maintain homeostasis, the sympathetic nervous system drives your “fight-or-flight” responses. Ideally, within your autonomic nervous system, the ongoing tug of war between these two polar opposite mechanisms creates a "yin-yang" type of harmony marked by homeostatic balance.
From an evolutionary perspective, one could speculate that our ancestors relied on the sympathetic nervous system to kickstart cortisol production and other neurobiological responses necessary to hunt, gather, and ward off enemies. Conversely, the parasympathetic nervous system probably relied on oxytocin to fortify our innate drive to nurture close-knit human bonds, procreate, and build survival-based cooperative and supportive communities, as well as romantic partnerships.
Unfortunately, the Toffleresque “future shock” of the 21st-century digital age (marked by too much change in too short a time) is causing many of our ancient evolutionary biological systems to short-circuit. All too often, social media and other modern-day factors are reducing face-to-face social connectedness and exacerbating feelings of perceived social isolation or being an outsider who is unworthy of love and belonging.
For example, a national analysis conducted by researchers at the University of Pittsburgh School of Medicine found that young adults in the U.S. who use social media more frequently than their peers report higher levels of perceived social isolation. The March 2017 report was published in the American Journal of Preventive Medicine.
Brian Primack, director of Pitt's Center for Research on Media, Technology, and Health (CRMTH), and colleagues found that participants who used social media for more than two hours a day had twice the odds of reporting perceived social isolation than their peers who spent less than 30 minutes on social media each day.
Primack encourages doctors and health practitioners to ask patients of all ages about their social media use and to counsel them on the benefits of reducing screen time if it seems linked to perceived social isolation. Other research has identified the disruptive role that actual and perceived social isolation has on the parasympathetic nervous system as marked by changes in HRV and vagal tone.
As an example, in 2009, a study published in Health Psychology reported that participants with symptoms of depression who felt socially isolated displayed lower HRV. However, when these individuals were engaged in face-to-face social interactions with a partner, family members, or friends their parasympathetic response and HRV increased. These findings suggest that real-world social connectedness can negate the stress responses of fight-or-flight by tapping into the parasympathetic response of our innate need to tend-and-befriend.
Another 2009 study by researchers at the University of Illinois at Chicago, “Social Isolation Disrupts Autonomic Regulation of the Heart and Influences Negative Affective Behaviors,” reported that female prairie voles (who are notorious for bonding via oxytocin) displayed a reduction in HRV when placed in solitary confinement. Additionally, the researchers stated, “These changes in response to social isolation showed predictable interrelations and were mediated by a disruption of autonomic balance including both sympathetic and parasympathetic (vagal) mechanisms.”
For decades, I’ve associated the parasympathetic urge to “tend-and-befriend” as being rooted in oxytocin, which has typically been thought of as the “cuddle molecule” or “love hormone.” Whereas adrenaline and cortisol fuel our “fight-or-flight” response, oxytocin is at the heart of our innate urge to form close-knit human bonds and the parasympathetic response to take care of one another. Interestingly, it turns out that oxytocin levels surge when a romantic partner feels that his or her relationship is in danger.
A potentially game-changing new study, “Oxytocin and Vulnerable Romantic Relationships,” by the Norwegian University of Science and Technology found that oxytocin levels spike when someone feels that a partner is losing interest or there is an urgent need to fix the relationship. These findings were published May 18 in the journal Hormones and Behavior.
Hypothetically, based on the tug of war within the autonomic nervous system to create an even-keeled (homeostasis) feeling of safety and belonging, this study makes sense. If one partner is driven by a sympathetic nervous system urge to "take flight" and abandon the relationship, a surge of oxytocin in the other partner seems like the logical evolutionary parasympathetic response to nurture and maintain an intimate bond. In a press release, co-author Steven Gangestad said, "What's implied here is a statement about what oxytocin is doing: It's perhaps fostering attention to and motivation to 'take care of' the relationship."
In what appears to be a biologically hardwired prosocial response to save a relationship, the researchers found that the “love hormone” is released during times of romantic crises. Andreas Aarseth Kristoffersen, a research assistant in NTNU's Department of psychology added, "When people notice that their partner is showing less interest in their relationship than they are, the level of this relationship-building hormone [oxytocin] increases."
In 2012, another interesting study on the "love hormone" by researchers from the University of Sydney identified a correlation between administering nasal oxytocin and increases in both social connectedness and heart rate variability (HRV). These findings were published in the journal PLOS ONE. The researchers concluded,
“Together with the broader literature on Oxytocin (OT) and HRV, findings suggest that acute administration of OT may facilitate a fundamental psychophysiological feature of social behaviour, increasing capacity for social engagement. Findings also suggest that HRV changes may provide a novel biomarker of response to OT nasal spray that can be incorporated into research on response to treatment.”
Lastly, in 2010, a landmark study by Bethany Kok and Barbara Fredrickson identified a correlation between feelings of social connectedness, parasympathetic activity, and positive emotions as indexed by robust vagal tone. The findings were published in the journal Biological Psychiatry. The authors write,
“Adults who possessed higher initial levels of vagal tone (VT) increased in connectedness and positive emotions more rapidly than others. Furthermore, increases in connectedness and positive emotions predicted increases in VT, independent of initial VT level. This evidence is consistent with an “upward spiral” relationship of reciprocal causality, in which VT and psychosocial well-being reciprocally and prospectively predict one another.”
Hopefully, identifying the ability of excessive social media use to exacerbate feelings of perceived social isolation (as marked by a reduction in HRV and vagal tone) will serve as a reminder that you can create an upward spiral of positive emotions by "tending-and-befriending" others through face-to-face social interactions. As I mentioned earlier, this entry is "phase three" of a nine-part Vagus Nerve Survival Guide series. Please stay tuned for upcoming posts.
Nicholas M. Grebe, Andreas Aarseth Kristoffersen, Trond Viggo Grøntvedt, Melissa Emery Thompson, Leif Edward Ottesen Kennair, Steven W. Gangestad. Oxytocin and vulnerable romantic relationships. Hormones and Behavior, 2017; 90: 64 DOI: 10.1016/j.yhbeh.2017.02.009
Brian A. Primack, Ariel Shensa, Jaime E. Sidani, Erin O. Whaite, Liu yi Lin, Daniel Rosen, Jason B. Colditz, Ana Radovic, Elizabeth Miller. Social Media Use and Perceived Social Isolation Among Young Adults in the U.S.. American Journal of Preventive Medicine, 2017; DOI: 10.1016/j.amepre.2017.01.010
Schwerdtfeger A, Friedrich-Mai P. Social Interaction Moderates the Relationship Between Depressive Mood and Heart Rate Variability: Evidence From an Ambulatory Monitoring Study. Health Psychol. 2009 Jul;28(4):501-9. DOI: 10.1037/a0014664
Angela J. Grippo, Damon G. Lamb, C. Sue Carter, Stephen W. Porges. Social Isolation Disrupts Autonomic Regulation of the Heart and Influences Negative Affective Behaviors. Biological Psychiatry, Volume 62, Issue 10, 1162 - 1170 DOI: http://dx.doi.org/10.1016/j.biopsych.2007.04.011
Andrew H. Kemp, Daniel S. Quintana, Rebecca-Lee Kuhnert, Kristi Griffiths, Ian B. Hickie, Adam J. Guastella. Oxytocin Increases Heart Rate Variability in Humans at Rest: Implications for Social Approach-Related Motivation and Capacity for Social Engagement. PLoS One. 2012;7(8):e44014. DOI: 10.1371/journal.pone.0044014
Bethany E. Kok and Barbara L. Fredrickson. Upward spirals of the heart: Autonomic flexibility, as indexed by vagal tone, reciprocally and prospectively predicts positive emotions and social connectedness. Biol Psychol. 2010 Dec; 85(3): 432–436. doi: 10.1016/j.biopsycho.2010.09.005