How stress in children’s lives can change their trajectories as adults

Stress vs. Toxic Stress

Dionissi Aliprantis

What is toxic stress? Is this the same thing as simply facing some adversity?

Dr. Garner

Toxic stress refers to the ongoing unmitigated biological responses to threats that happen in the absence of social, emotional buffers. So toxic stress is not about the precipitants or the triggers that's important, it's really about the body's stress response to those events. So again, it's an important distinction because we tend to think about different stressors or triggers, but those range from distinct catastrophic threats like violence or bullying to ongoing chronic conditions like poverty or exposure to racism. And the events or triggers can be very subjective, so one child hears a dog barking and thinks, "Ooh, puppy let's play," and another is, "Keep that beast away from me." And so some of that has to do with their previous experiences. And on the other side too parental encouragement might be perceived as being very supportive or it could be perceived as applying undue pressure. You're going to have a hard time getting objective handle on a wide range of adversities, unless you start looking at the response. Because the biological response is something we can begin to quantify and observe objectively. We adapt to chronic stress at the molecular, cellular and behavioral levels. It can truly change who we are.

Dionissi Aliprantis

Can you describe the mechanisms by which stress becomes toxic?

Dr. Garner

Not all forms of stress are toxic; only those forms that are prolonged or frequent or extreme because there's no social, emotional buffering to turn the stress off and bring it back to the baseline. In fact, in the presence of safe, stable, nurturing relationships, stress responses can actually be positive and build resilience and skills to deal with future adversity in an adaptive manner. As examples, consider a 15-month-old who can't express themselves and therefore has a tantrum, to which we respond to the non-verbal cues. Likewise, we're going to offer consolation to a two-year-old who does a face plant while running. And even a middle schooler who has an overwhelming project, we're going to help them break that down into little bits that seem a little more manageable.

The point here is that positive stress is not the absence of stress. We don't want to put kids in a stress-free bubble, we actually want to give them the skills they need to adapt to adversity in a healthy manner moving forward. I think that's an important point because in society we tend to let kids know in a million different ways that strong emotions are bad. “You're not allowed to feel that way.” “You're not allowed to have strong emotions, and if you do there's something wrong with you.” And that's really not healthy!

Big emotions are okay, but they demand a distraction. And I think there's three different kinds of distractions: There are healthy distractions, there are escapes, and there are unhealthy distractions. The healthy distractions are the kids' passions. We want to tap into these, the drawing and the reading and the music and the dance and the sports and the Rubik's cube and the chess, because they build skills, often generalizable skills, which are going to help the kids down the line. But some distractions are escapes. Consider passive entertainment like YouTube or TV or video games. While they are potent distractions, they're not really helping you build new skills. So they're fine now and then; we all need ways to blow off steam now and then. But if they become a default mode of coping, then we're starting to cut into the skill-building time.

Dionissi Aliprantis

How is toxic stress related to the labor market?

Dr. Garner

The takeaway from the research is that unmitigated adversity in childhood has the potential to change who we are. Adverse Childhood Experiences (ACEs) have the potential to alter learning, behavior and health across lifespan. And so all those features are going to clearly impact on a person's economic productivity.

Our responses to stress are rooted in biology

Dionissi Aliprantis

We evolved in a very different setting than the one that we live in now. And so these responses that in that other setting probably were very adaptive, very helpful, they can be very maladaptive now. I'm curious if you could speak a little bit about toxic stress and brain development, especially the way that these early experiences can get under your skin.

Dr. Garner

I like to picture it this way: There are these wide arrays of child experiences, both adverse and nurturing, I should say, and then there's this proverbial big black box. And then decades later we have these adult outcomes, some of them are good, some of them are bad. And so it's really like: What's going on inside the box?

One idea to help us look inside the box is this idea of epigenetics. So epigenetics literally means above the genome and what it refers to are changes in gene expression that are not related to changes in the actual sequence of the DNA.

Dionissi Aliprantis

Sorry. As someone whose biology could use a little tuning, can you explain what that means? A change in someone's DNA, what does that mean?

Dr. Garner

So a gene can either be turned on, or it's turned off. There are many different types of genes, some genes get turned on and turn on a whole set of cascade of other genes. So we know in development, there's some genes that turn on and now you're going to get a limb there. There are some genes that are almost circadian, they go on and off very dynamic. So that makes sense.

But there are some genes that are programmed early and then they persist across the lifespan. And so that's an important thing to understand is that what happens in early childhood, again, it can affect what happens down the line, there's almost an imprinting.

The idea of epigenetics, though, is that what turns on those genes on and off is the environment. So that's critically important because we tend to think of the genome as being fixed, that was the old model. If you inherit these genes, you know what your destiny is. And there are models like that. If you know anything about Huntington's disease, we know that if you inherit that gene it's pretty likely you're going to have problems down the line, but the vast majority of genes are not like that. We know that the environment plays a role and can determine whether or not that gene gets turned on or not.

So this is really liberating. So if you inherit a gene that makes it very likely for you to be an alcoholic, but the environment never turns that gene on, well, it's not really much of a risk. So this is really good news that the genome is almost somewhat plastic. The American Academy of Pediatrics says, "Epigenetics is not your parents' genome." The idea being that just because you inherit the same genes as your parents, does not mean that they're going to interact in the same way, the same permutations of genes are going to get turned on because of how the environment impacts that.

Another way to get inside the black box of how early experiences affect adult outcomes is the way the brain forms.

The problem is that, particularly when we're talking about stress, the on switch for the stress response develops relatively early in development. This is the limbic system, this little almond-sized thing called the amygdala. It develops relatively early in development, which makes sense. Evolutionarily, you want to shoot first and ask questions later, or there may not be a tomorrow. But as we get older, we want to be able to step back and begin to think about what our options are. And so the off switch for the stress response is this thing called the prefrontal cortex that is right behind our eyes. Some people have called this the seat of civilization, with the key feature that makes us human being our ability to think abstractly, to prioritize, to decide this is more important than that. The prefrontal cortex also allows us to regulate our emotions. And so that's the off switch for the stress response. But the problem is that off switch doesn't mature completely, at least structurally, until you're 24.

So the on switch for the stress response is screaming through most of development, while the off switch is finding its voice. So you can see, if there is some significant adversity in childhood, it may be a lot harder for those kids to turn off that stress in and of their own volition. In such scenarios, the kids need those safe, stable, nurturing relationships to help learn.

There's a related concept there, and that's an important one called behavioral allostasis. So sometimes the way to get back to normal is through behaviors, that help us cope with stress. So for example people smoke and drink and eat and have sex, that all turns off the stress response in a short term. And so they could be considered adaptive from a toxic stress perspective, but clearly they can become health harming over time, particularly if they become addictions or our default means of coping with stress. So one of the really insightful participants of the ACE study once told Dr. Felitti, "Doc, it's really hard to get enough of something that almost works." So all those things almost work. Whether it's smoking, having sex, they almost work and so it's very easy to see how they can become addictive. They become our default means of coping, but in the long run, they can be health harming. [Listen to the audio conversation above for more details about Dr. Vincent J. Felitti, co-principal investigator of the groundbreaking Adverse Childhood Experiences (ACEs) study.]

Safe, stable, nurturing relationships are key to overcoming toxic stress

Dionissi Aliprantis

I was wondering if we could now turn a little attention to this idea of relational health. So we talked a little bit about toxic stress and you described the way that we can react to environmental stressors. That can be okay, that can be maybe even positive, but it can also be toxic. But you point out that toxic stress, this whole framework is problem-focused. It's focused on what happens biologically without any mitigating social or emotional buffers. So you had a recent policy statement where you were emphasizing the potential of focusing on relational health and you see that as a solution-focused approach. I'm wondering if you could elaborate on that. What do you mean by relational health and what do you mean by it being solution-focused?

Dr. Garner

Producing positive adult outcomes is not just about reducing the negative experiences kids have growing up. It seems to be an even greater priority to create positive experiences for kids, and ensuring these positive experiences seems to matter in many ways. Negative experiences can be overcome by positive experiences—nurturing relationships are restorative and allow kids to have good outcomes even when facing adversity. Moreover, we may be better off to face adversity with the support of nurturing relationships than to lack both adversity and nurturing relationships.

Toxic stress really helps us define the problem. So many of our society’s most intractable problems, including disparities in economic productivity, but also education and otherwise, are rooted in our shared biology being lived out across divergent experiences and opportunities. This is where relational health really helps us define the solution. The individual family and societal capacities to develop and maintain safe, stable, and nurturing relationships also buffer adversity and build the skills needed to be resilient, healthy, and productive citizens. These capacities also build the safe, stable, and nurturing caregivers for the next generation.

I would say that minimizing adversity is necessary, but it's not sufficient. And there's good data to support that. There was a study published by Christina Bethell on the flourishing of kids. She defined flourishing in terms of questions like, “Is the kid curious?”, “Do they complete tasks?”, and “Do they stay in control?” Let me be clear. That's a high bar, as I'm not sure I meet that bar most days. These questions are aimed at identifying executive function, which is the prefrontal cortex we were talking about. After defining this measure of flourishing, what Bethell’s study showed was that there are more kids flourishing that have high adversity and high family resilience and connection than kids that have no adversity but little family resilience and connection. This was a light bulb moment for me. I think what this really drives home is that we tend to think of adversity and nurturing experiences as being two ends of one axis. But the reality is adversity and family connection are two completely different axes that coexist in kids' everyday lives.

Dionissi Aliprantis

So you could have a really adverse experience one moment, and then a couple moments later, you could have some really nurturing relationship or some really nurturing experience.

Dr. Garner

Absolutely. And it's that restorative thing that's so incredibly important. It's so incredibly important. Because if we just consider an ACE score, you might predict a kid would do relatively poorly in terms of being well. And if you factor in that they've had few positive child experiences, you might predict that they would do even worse. But if you factor in the positive experiences, they may actually fare relatively well.

And that's what Christina Bethell's data shows. If you have adversity, but you have those nurturing relationships, you may actually do pretty well. And then this is the kicker for me: The reverse is also true. So just because you have material wealth and you have these positive experiences does not necessarily mean you're in the clear. So if you have few adverse experiences and you have some great positive experiences, well then yeah, you're probably going to do pretty well. But if you have low adversity, but you have low relational health, you're going to not do as well. And that's clear from her data. And so that's why this research is so important to me personally. It's not just about those kids, it's about biology. We all need relational health to reach our full potential.

The opinions expressed in this article are those of the participants and do not necessarily represent the views of the Federal Reserve Bank of Cleveland or the Board of Governors of the Federal Reserve System.