Although post-traumatic stress disorder is an established diagnosis in psychology, and stressed combat veterans are a cliché in Hollywood, it wasn’t long ago when PTSD wasn’t well understood at all. “There was a time when our lack of knowledge about post-traumatic stress disorder was really harmful and resulted in the fact that a lot of people did not get treated or treated properly by the healthcare system,” says Rachel Yehuda.
In the past 25 years, Yehuda has done as much as any scientist to understand the debilitating disorder. Yehuda, a professor of psychiatry and neuroscience, is the director of the Traumatic Stress Studies Division at the Mount Sinai School of Medicine in New York City. She has worked with war veterans, Holocaust survivors, and other trauma victims to gather insights for numerous research papers that detail the biological roots of PTSD.
I don’t think courage is the absence of fear. I think that courage is forging ahead even though you’re really scared.
“You’re no longer talking about whether there is or isn’t such a thing as post-traumatic stress disorder,” Yehuda says. “We’re now having a conversation about whether all the effects of trauma are negative, or whether some of the biological changes we see are the body’s attempt to cope and adapt and restore things in the face of destruction. It’s like when one god shuts a door, he opens a window.”
On a drizzly afternoon in December, Yehuda braved the rush-hour traffic from her Bronx office to Midtown Manhattan for an interview. She was anxious, she told us, to clear up some of the lingering myths about PTSD, and explain how probably two-thirds of the population have been exposed to a serious traumatic event in their lives. “I have to warn you,” she said with a smile, “I can be very opinionated.”
The video interview plays at the top of the screen.
How would you define trauma?
It’s still being debated, “what is a trauma.” Do you have to actually feel your own life is threatened? Can you watch somebody else’s life being threatened? Well, the answer to that in the current DSM-V is yes, you can witness traumatic experiences in other people. It could be something shocking, it could be something horrifying. Does the event have to be very unusual compared to your life circumstances? You know, maybe not. Some people live in circumstances where they’re repeatedly exposed to life-threatening or traumatic events, so that’s possible too.
The way that I like to define a trauma is a watershed event, an event that kind of divides your life into a before and after. I think that most of us can understand what that means. For example, 9/11 was a watershed event to many people living in New York. Before 9/11 things were one way, but after 9/11 things changed. And it becomes an event in a very personal way because you feel that there was a pre-event you and a post-event you. So it’s a watershed event that is cataclysmic, horrible, terrifying—and that changes you.
Why don’t all people exposed to trauma get PTSD?
It’s a very important question. The best answer I could give you, to date, is that people respond differently to events. This again is another paradigm breaker because when we first were starting to define what the stress response was, the idea was that there was kind of a uniform response, that everybody would respond to challenge in a similar way. Maybe that’s true for short-term stress, but even then I think there are individual differences.
Sometimes the effect of trauma doesn’t manifest as a memory that haunts you, but as this idea that I’m broken, that I can’t find myself.
I think the short answer to why we don’t all get post-traumatic stress disorder (PTSD) is that we come into trauma with different histories, we come in with different genetics, we come in with different expectations, with different cognitive interpretations, with different resilience capabilities, with different brain functioning. All that mixes together in a unique way so that PTSD is one very important and almost prototypic response to trauma, but it certainly isn’t the only way that traumatic events stick with us.
What causes stress to turn into a disorder?
So why does it turn into a disorder? One idea is that people who develop PTSD started out, even before the disorder, with a different way of metabolizing or dealing with a traumatic event; the die was cast even before. It could’ve been an earlier traumatic event or earlier adversity—or even what’s been very interesting in our research lately is the possibility that there are epigenetic changes that may have been transmitted from an earlier generation or generations. For whatever reason, people start out with this different capacity to fight off the body’s tendency to form traumatic memories.
So the die is cast, we’ve said that. For some people, the event brings up so much distress and so much arousal, and releases so much adrenaline, that it is impossible to calm down as quickly as one needs to in order to avoid forming traumatic memories. Now our work has suggested that one of the hormones that doesn’t kick in well enough to prevent the norepinephrine levels from coming down might be cortisol. Cortisol levels are often increased in times of stress and they are increased in everybody; it’s part of the “fight or flight” response. But it may be then in some people the levels of cortisol aren’t high enough at the time of the stress to bring down fully the sympathetic nervous system so that we can calm down.
Being calm after a trauma is really an important key to determining who might develop PTSD. But that’s not the full answer because we now know that there are a lot of people that develop delayed PTSD and we don’t really have a good biologic explanation for that yet. We used to think that PTSD was just the continuation of an acute response that just didn’t dampen down. We now know that that isn’t true for everybody and that there have to be other kinds of processes that are involved in why PTSD develops in the first place and is sustained over a chronic course. It’s more than just a failure of the body to mobilize resilience and recovery.
Is replaying a bad memory in your mind what causes PTSD?
I think that can be part of it. I think if the memory comes back to you and you don’t think of something comforting—thinking instead of something more terrible—it’s going to make the impact of that memory worse. For example, if you’ve been involved in a car accident, and you have the memory of the crash, and linked with that memory is guilt for what you could’ve done differently, then that will make that memory very, very traumatic and every time that memory comes to you you’ll have more and more of an emotional arousal. And pretty soon that memory will be very, very distressing and intrusive.
But if you can have a memory of an event and then sort of talk yourself into a less aroused place—“It wasn’t my fault,” if you could say to yourself, [which] many of us can [but] some of us can’t—then that might have the ability of calming you down, so that next time you have the memory, you’re a little more calm, and more calm, and more calm. I think again, it gets back to this idea of a sustained arousal and distress, and that has a lot to do with what you think about what happened.
I don’t define resilience as the absence of PTSD; I just don’t. I think that people can have PTSD and be extraordinarily resilient.
People feel a lot of shame when they’re traumatized, they feel a lot of guilt when they’re traumatized; they feel also some fear or horror. If you say, “Oh my God, I’m never going to be safe again!” then that gives that memory more emotional heft than if you say, “Okay, next time, I’ll be prepared.” The thoughts that you’re thinking will also modulate your biologic response, and so I think that you can work yourself up into a cascade, where if you keep having negative thoughts—shame, guilt, self blame, fear, helplessness—all those are kind of interpretations that you have of your bodily state, and they can end up really making the memory of the event very, very distressing. And of course that will cause you to avoid, to retreat into your shell to try to not think about what has happened. Pretty soon you have the cascade of PTSD symptoms and they’re very hard to get rid of.
Can people ever forget traumatic memories?
I think that it’s a fantasy, like that movie, The Eternal Sunshine of the Spotless Mind. We sometimes have this fantasy that we’d be better off if we didn’t have our memory or if we could distort our memory so that the ending would be good and not good. But ultimately our job is to grapple with the fact that we experienced something traumatic and it means something important that we experienced it. And now we have an obligation to find meaning in it and we have an obligation to move forward with that memory, because if you erase the memory you erase yourself, because you are your memory. So what we want to help people do is live with the memory, have the memory be less distressing, transform the memory in some way, not transform the veracity of the memory, but transform the response to the memory.
Does reliving a traumatic memory in therapy work to relieve it?
There are people that respond very well to specialized PTSD treatments that are focused on reliving the traumatic memory. I think it’s a really powerful treatment for those who can tolerate the treatment and those who have, really, a memory that is fear-based or something like that. I’ve seen it work; I’ve seen it work well. But I also think we need alternatives for people who can’t tolerate doing that kind of therapy, or who aren’t really traumatized by a specific memory but just feel a sense of being different or alienated or “other” or broken.
Sometimes, the effect of trauma doesn’t manifest as a memory that haunts you, but it manifests more as this idea that I’m broken, that I’m hollow, that I can’t find myself. For that, I’m not sure that reliving a memory will fix that. So I think that a good therapist listens very carefully to what the problem is, what the symptoms are, what the experience of someone is in the here and now, and tries to run through the different kind of treatment options that could be brought to bear to help somebody. Because feeling empty is very different than feeling haunted, and you wouldn’t expect them to necessarily respond to the same kind of intervention.
Some psychologists have implied PTSD may be overstated, that people are more resilient than we give them credit for.
I don’t define resilience as the absence of PTSD; I just don’t. I think that people can have PTSD and be extraordinarily resilient. I also think that just because you don’t have PTSD doesn’t mean you’re unscathed or unaffected. I think our experiences change us. Little experiences also change us, maybe a little, and big experiences change us a lot. The question is, can we get to a place where we take our traumatic experiences that have changed us and somehow recalibrate or readapt to our new life with our transformed self.
I define resilience as really that process of emerging from a traumatic experience, trying to be transformed in a positive way, and not just allowing the trauma to color everything negative or nihilistic. I think that a lot of people that struggle with nightmares and flashbacks and insomnia are fighting the good fight for resilience. I just don’t look at it as binary.
Now, why don’t some people get the syndrome of PTSD could have to do with how the symptoms are grouped. But most people who are exposed to very traumatic events will have nightmares about it; they just will. Or they’ll be distressed when they think about a traumatic reminder. The difference between whether they can function or not, now that’s the critical piece. When you have a nightmare, can you go back to sleep? Or are you done for the night? When you have a distressing thought, do you have to completely stop what you’re doing because you’re just flattened by it? Or can you take a moment to honor the memory, reflect on the fact that this is a natural response to the fact that something important happened to you, but then put it aside and kind of move forward? I think that these are some of the things that we want to understand a little better—not just this binary, if you have PTSD you’re not resilient and if you don’t have PTSD—that just isn’t my experience.
It’s very difficult to come home to families who have been waiting for you, thinking you’re the same person, when the experience of deployment has changed you in fundamental ways.
What are PTSD’s lasting effects?
What’s really insidious about PTSD is that it affects your entire health, and we’ve been so busy talking about the psychological aspects—the flashbacks, the nightmares—that perhaps we haven’t paid enough attention to the fact that people with PTSD experience a deterioration in their health and physical wellbeing. They eat more poorly, they sleep more poorly, they develop insulin resistance earlier than people that have not been traumatized or don’t have PTSD. They’re at greater risk for metabolic illness, such as diabetes and hypertension or metabolic syndrome. They’re at greater risk for autoimmune and inflammatory illness. They’re at greater risk for cognitive disorders. So traumatic stress is a very big assault to the entire body. People that have PTSD are also more likely to develop depression or other anxiety disorders. If the trauma that you’ve experienced involves a physical assault or a blow to the head, then that can also cause a mild traumatic brain injury, and when coupled with PTSD, [that] could have really pervasive effects. So it’s important when we talk about the effects of trauma and PTSD to not forget how big it can go. But on the other hand, we should also not forget that this is not the response that everybody has to trauma and that people are also extremely capable of resilience and adaptation.
How would you define courage?
So I don’t think courage is the absence of fear. I think that courage is forging ahead even though you’re really scared. Do you let the fear immobilize you? Or do you let the fear strengthen you? Or do you put the fear aside and just do what you have to do so that you could survive a situation that the fear might otherwise prevent you from surviving, right? So I think that fear is not a negative or harmful emotion. It is the body signaling you, appropriately, that there is a threat that you need to attend to. And if you didn’t have fear when you were in danger, then you would be someone’s prey; or you would not be able to do what you needed to do to run or to escape or to freeze, if that’s the most adaptive thing.
Fear becomes a problem when you experience it when there’s no threat. If you start to organize your life because you were once afraid, because there was once a reason to fear, [if you] begin to say, well that means that I should be afraid that whatever happened to me is going to happen again, then the fear can become paralyzing. So it’s in balance, right? You don’t want to forget what happened to you because you’re supposed to learn from it, right? If you’re in a dangerous neighborhood and you get mugged, you’re meant to learn a lesson about that neighborhood, and you’re meant to generalize it a little bit—but not completely. You can’t say every time I go out I will be mugged, because that will become paralyzing.
What does PTSD tell us about human nature?
That the machinery is working! I think that the responses to trauma of fear and arousal, and maybe sometimes even numbing and dissociation under certain circumstances, are our body’s way of coping with threat and danger. We need these mechanisms to help us. We also need to be able to remember traumatic experiences; we need to carry with us memories of danger. So there’s nothing inherently pathological about having a stress response; we want stress responses when we have stress. We might challenge the notion of how helpful stress is to us, but even there, [I] don’t believe anyone ever promised us a rose garden! We are built, we have evolved, we have been created—however you want to look at it—to be able to deal appropriately with challenge. When we are confronted with challenge our bodies react and respond, so I don’t think that that in and of itself is pathological, and I don’t think it should be treated as such.
What has years of working with veterans taught you about war?
It’s expensive. War is expensive, and not just the dollars. When people go to war, even if there are good reasons to do so, it takes a toll. It’s expensive for families and societies. Being confronted with death, having to make very difficult decisions, having to wonder whether it’s worth it for you, or someone else, to give their life for an ideology, it takes a toll. It colors the way everything else is viewed. You can’t really go to a ball game in the same way again! So I think that we have to understand that. In today’s warfare, more people are staying alive, which is great, but we have to really understand that the effects of war can last for a very long time.
If you feel traumatized, good! Don’t just cower in a corner with it. Use it as a message for action, it’s a call for action.
That doesn’t mean that everyone comes back as a mental health casualty. It’s very important that when we say that people are affected by an experience, we don’t jump to the conclusion that we necessarily mean that they have a mental health disorder, even though there’s no shame in that—because I think that this also makes the discussion very difficult. If somebody wants to come home and tell you that they’re different because they no longer care about the same things they used to care about—they see the world differently—you can’t immediately say, well, go take an antidepressant for that, because that’s not what they’re saying to you. So we want to be able to have a conversation where we are able to talk about a great range of changes that occur, and not all of them are negative, and not all of them are maladaptive. I think that being able to communicate the fact that you’ve changed and the good parts of that—and the not so good parts of that—is a very important thing to do.
Why is it hard for combat veterans like those in American Sniper and The Hurt Locker to adjust to life back home?
Well, in order to become a solider you have to train and become very disciplined and become very focused. You develop unit cohesion; you develop a new family of your military comrades; you get used to the unexpected. You’re in life or death situations [and] you have to make very difficult decisions. Your diet is different, your level of physical activity is different, the things you care about are different, right? So in The Hurt Locker, that was a great scene. I mean I haven’t thought about cereal in a long time, why there are so many. That’s very different than thinking about whether if you pull a wire out you’re going to blow yourself up. It’s just a very different kind of existing. It’s very difficult to come home to families who have been waiting for you, thinking that you’re the same person that’s coming home, when the experience of deployment has changed you in fundamental ways. The person that’s coming home might not be the same person that’s left, but still nonetheless, has to be embraced and welcomed.
We often say we’ve been “traumatized” by something like a news event. Do we have the right to use that word in light of combat veterans?
Of course we have the right! I think that what we perhaps do not do enough of is take our feelings of being traumatized and take the next step with them. So what does that mean, you’re traumatized? Do you feel helpless? Do you feel like maybe you’re worried the same thing will happen to you and what will you do in that environment? Well, what are you going to do to make the world a better place? Or, what is your game plan for making sure your society is safe, or your community is safe? How are you going to get involved in helping make the world a better place? So if you feel traumatized, good! Don’t just cower in a corner with it. Use it as a message for action, it’s a call for action.
I think that our emotional responses are gifts. We’re designed to be able to detect danger; or we’re designed to be able to respond to thoughts even that can’t hurt us really, physically. So the question is, what are we going to do with our feelings? And what we need to do is provide leadership on what somebody should do when they’re feeling helpless or feeling afraid or feeling traumatized, because I think people will feel less helpless if they know what to do when confronted with something that is scary for them, or something that is dangerous.
Can PTSD ever be good for you?
I don’t know. You know, I’m the type of person that likes to play the hand I’m dealt. You know, I don’t wish I had two aces! I don’t know if it’s good for me or if it’s bad for me; it’s my reality. I think that part of what I find so interesting in terms of the cultural differences in the response to trauma really boils down to whether or not you feel lucky or unlucky, somehow, because you’ve been exposed to trauma or not.
I think the way that we need to look at it is that sooner or later we will have to face an extraordinary challenge, and many of us will have to face more of them. Are we optimally equipped to deal with these challenges? Little challenges make us more equipped to deal with big challenges. Big challenges may help us not sweat the small challenges. I think it’s a matter of what we decide. I think we have to empower people, that they have some control over their reactions to events. They can’t necessarily control all their symptoms, but they can control the meaning of the events. And I think through that, there might be a way to make symptoms more tolerable.
What would you be if you weren’t a scientist?
I would like to be a musician!
Do you play anything now?
I play things badly. But if I weren’t a scientist, I would devote more time to my hobbies. But if I had to work for a living …
What are your hobbies?
My hobbies, at the current time, are music, cooking, and yoga. But I think that if I weren’t a scientist, I would want to do social justice, I think, because I find that very empowering. Or, I would want to do something where my abilities could really improve the lives of someone else. I think that’s very important.