Depressed person wearing a hoodie

Do you seem to be passive in relationships and tolerate unhealthy behavior in your partners or family members? Do you find you have too many narcissistic people in your life? Have you been in an abusive relationship? 

A new study may offer a biological explanation for why some people, based on their levels of early life stress, may tolerate unhealthy relationships in adulthood and be more anxious than others. 

As a survivor of violence and abuse from my second husband and abuse from a narcissistic father and sister, this topic is interesting to me. As a psychologist, I also regularly work with people who have experienced abusive relationships of all types. 

Bear with the scientific lingo as I explain, because this is a cool study.

It tracked two neuropeptides: oxytocin (OT) and arginine vasopressin (AVP). OT is often called the “cuddle hormone” or the “love hormone,” because it increases when we engage in  physical touch and when we are in loving relationships.

Together, OT and AVP “oversee the social-emotional functioning of humans (e.g., social bonding, social aggression, vigilance to social threats).” You’d think that these neuropeptides would work the same way in everyone, but apparently they don’t, according to this study. 

The researchers in the study found that “the function of OT and AVP changes in an evolutionary predictable way according to people’s early life stress — OT and AVP maximize alertness to threats and social-based survival for people who experienced high levels of early life stress, but not for those who experienced low levels of early life stress.” 

Basically these neuropeptides seem to change how they work depending on if a person grows up in a safe, calm environment, or an unsafe, chaotic environment. This helps maximize the person’s survival. 

The study’s abstract states: “In a series of two studies, we show that early life stress is associated with change in the core function of OT and AVP in evolutionary predictable ways: Under high early life stress, AVP promotes threat-detection capabilities, whereas OT motivates non-selective proximity seeking to others. Conversely, under low early life stress these neuropeptides have an opposite, yet adaptive response: AVP promotes low vigilance and preservation of energy, whereas OT increases detection of interpersonal flaws. Our results demonstrate the plasticity of neuropeptide functioning that mirrors the variance in human social-emotional functioning.”

Translated, this means that children raised in adverse situations (abuse, harsh parenting,  neglect, poverty, war, etc.) grow up to be on guard for danger and have higher levels of overall anxiety.  They also learn to tolerate bad behavior in others. 

Those raised in calmer, safer environments, are less anxious and better able to sort out the bad actors from the good actors in their social world. “Based on the accurate detection of social cues, oxytocin prompts trust and/or suspicion, because in a safe environment one has the privilege of being selective.” 

This does not mean either of these adaptations is unhealthy. Just the opposite. Developing heightened reactivity to stressors may confer selective evolutionary advantages.

“Among people with a history of stressful and insecure interactions and a relatively unsafe environment, the need to maintain interpersonal proximity, and thus security, may

override considerations that otherwise promote selectivity. Thus, OT is expected to increase affiliation tendencies among people with early life adversity to the point of overlooking other people’s flaws, because in stressful environments being with others, even imperfect others (e.g., unfaithful romantic partners), enhances survival more than being alone.”

Think of it this way: Say you are living 10,000 years ago and your tribe’s camp is suddenly invaded by another tribe. As you grab your axe to do battle, you turn to look and one of your tribe members, Joe the Jerk, is standing next to you . Most of the time, you avoid dealing with Joe. But in that instant, you can’t be picky. You have to trust him to truly have your back in the battle and you can’t quibble over his otherwise lousy personality. 

In the same way, the study indicates that children raised in high stress environments are both more worried and on guard, but also more willing to overlook abusive behavior, because their survival instinct tells them that any companion is better than no companion. We also know that the brain is not too picky about distinguishing types of threat. So even if there is no “invasion,” instead perhaps just a cold and unloving parent, the brain still responds with fear and may trigger neurochemical changes.

“Vasopressin regulates social-related threat by increasing vigilance and the motivation to act (Bos et al., 2012).”

Vigilance is enacted when cues in the environment, such as signs of physical danger or disconnection from others indicates a possible threat.  As social animals, our brains do not distinguish well between physical or social threats, such as rejection or criticism.

In the clinical setting, adults come to therapy trying to recover from abusive or narcissistic relationships, and in nearly 100 percent of the cases they have a parent and/or sibling who was abusive to them. They often have a history of repeatedly tolerating behavior in a partner or friend that is toxic or even abusive. This study shows they may have had their neurochemical functioning altered so that this pattern may be more difficult to overcome. 

This study seems to confirm what we know relative to “attachment theory” in psychology, that says we learn about relationship patterns based on whether our caregivers were responsive, supportive, and emotionally attuned to us. Secure attachment teaches a child to feel safe in relationships. Insecure attachment means a child has learned to distrust harmful or non-responsive others. 

The good news is that learning mindful self-compassion can teach one to generate feelings of soothing and safety, increasing the levels of oxytocin in the body, which may help counteract the effect found in this study.

The study was “Early Environments Shape Neuropeptide Function: The Case of Oxytocin and Vasopressin,” by Adi Perry-Paldi, Gilad Hirshberger, Ruth Feldman, Orna Zagoory-Sharon, Shira Buchris Bazak and Tsachi Ein-Dor, published 20 March 2019 in Frontiers of Psychology.

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