How you think about stress impacts the stress response in profound ways. So this paper, "Rethinking Stress, The Role of Mindsets in Determining Stress" did a very simple set of manipulations. They had people in one group listen to a lecture that effectively was titled, quote, "The effects of stress are negative and should be avoided." And that lecture included information about how stress diminishes performance and how it can diminish health and vitality learning and performance, productivity, it increases uncertainty, et cetera, okay?

And all of that information is true. A separate group listened to a lecture entitled, quote, "Experiencing stress improves health and vitality." And again, that information is true. Now, I realize that some of you are probably still asking, how can it be that stress diminishes health and performance and stress also enhances health and performance?

And the answer lies in two things. One, the level of stress, and therefore the level of hormones that are released in response to that stress, the duration over which the stress response occurs. But the key variable here is that our cognitive understanding about what stress does impacts whether or not our physiology goes down the direction of debilitating or enhancing effects of stress, okay?

So we've got a condition here where people are being informed very differently about what stress does. In one case, it's the stress is bad message. In the other case, it's the stress is good message. And there are many different experiments within this paper, but one of the more interesting ones I believe is where they looked at work performance, both in terms of performance of what they call soft tasks.

So these are somewhat easier tasks as well as hard tasks. And when you look at the group that was given information about how stress diminishes performance in the soft tasks, okay, so the somewhat easy tasks, you don't see much change in their performance as you compare the before the learning about stress is diminishing to after the learning.

Whereas the people who learn that stress is enhancing actually experience some improvement in work performance, even though the challenge that they're facing isn't that great. So again, what this means is that learning that stress can enhance performance by providing people true information about how stress can enhance performance, can increase performance even in the context of stuff that's not that hard, not that stressful.

Even more interesting is that when you look at performance on tasks that are considered hard and you compare the stress is diminishing group, meaning the group that was taught that stress is diminishing and compare that to the stress is enhancing group, you see a really divergent response. The people that learn that stress diminishes performance did not improve at all.

Whereas the people that learn that stress can enhance performance, enhance their performance significantly. Now keep in mind, all they are doing is learning that stress can enhance their performance and then they're given a task and they're performing better. So that's pretty spectacular, right? There's no training session that they went and did.

They didn't practice these items that they were being tested on in between. They weren't given a bunch of drills to do and they didn't take a lot of time to do it. They just heard a tutorial about how stress can enhance performance. And that I believe is remarkable because what it says is that our cognitive appraisal about stress, which we all are going to experience in life, right, elevated heart rate, narrowing of visual focus, shifting of blood away from the periphery.

All of these things are characteristic features of the stress response that we learn, especially in this day and age, 'cause it's talked about a lot in popular culture, that, oh, you know, all of these mechanisms were put into us in order for us to get away from the saber-toothed tiger or the lion that's trying to eat us.

Let's be fair. The stress response is there for a lot of reasons, not just because of saber-toothed tigers and lions. I mean, that's kind of a story that we make up. The stress response is inherent, not just to us, but to other species as a way to mobilize us either away from things or toward things, right?

We need to have somewhat of a stress response in order to engage in adaptive challenge. Yes, it's true that hundreds and thousands of years ago, those adaptive challenges probably involved hunting, but they probably involved social challenges as well. Do you think it was easy for cavemen and women to engage socially and kind of settle out their romantic interactions, et cetera?

Do you think it was easy for them to raise children? No, of course not. The stress response is there for a variety of reasons, not just to get away from predators. The really exciting thing that's been discovered in the course of Ali Crum's work and other work in the last couple of decades is that the stress response is neither good nor bad.

The stress response depends on whether or not you believe the sensations that you're experiencing, elevated heart rate, narrowing of visual focus, et cetera, are serving to enhance your performance or diminish your performance. And this study really points to the fact that just learning that it can enhance performance, can enhance performance.

Now, I know a number of you are probably saying, "Wait, but stress doesn't feel good," right? And oftentimes we experience stress under conditions where we're trying to learn or get good at something or listen better or do something, and it actually is diminishing performance. And I think it's important to acknowledge that.

This study and studies like it are not saying that stress becomes pleasant as a sensation in the body, nor is it saying that it always leads to improved performance. I don't want you to think that's the take-home message. Sometimes it does, it can, as was demonstrated in this research paper.

But oftentimes, as we know, stress diminishes our performance. It takes us away from the landmarks we want to hit. It takes us away from the grades we want to get. It takes us away from, quote unquote, showing up how we want to, right? No one wants to have the blotchy skin and the sweating and the quaking of voice when we're trying to do public speaking and things of that sort.

No one wants any of that. What's important to understand is that learning that stress is a way of mobilizing resources in the body does two things. First of all, it allows us to dampen or adjust the stress response in real time. And it allows us to understand that that stress response heightens our level of focus in a way that allows us to pay attention to the things that are going wrong in a way that allows us to make correction to those errors in the future.

So if you think back to that study, that ERP study, where they measured brain activity and they looked at people who had a fixed mindset versus people who had a growth mindset, and the people who had a growth mindset were paying more cognitive attention to what was happening during errors and after errors.

Well, this stress is enhancing mindset is very powerful because what it does is it shifts one's attention away from kind of somatic experience of, oh my goodness, my heart rate is elevated, I'm sweating, I'm quaking, I sound terrible, I feel terrible, I look terrible, et cetera, to a mode of allocating more of our thinking toward analyzing why things might be going wrong.

And something else powerful happens when we embrace a stress is enhancing mindset as well. When we embrace a stress is enhancing mindset, it turns out that some of the very physiological processes that we call quote unquote stress shift in important ways. Some of those include the duration over which the stress hormone cortisol is released.

And in fact, I don't even really wanna call it a stress hormone because cortisol does so many other things as well, and it's not bad. You need cortisol, believe me, you want cortisol, especially released early in the day and in response to acute stressors. What you don't want is for cortisol to stay elevated for long, long periods of time, and you especially don't want it to interfere with your sleep, okay?

So much so that I think at times I wonder whether or not our philosophy on stress should be that stress is fantastic for us except when it interferes with our sleep, right? And when stress becomes terrible for us is when it starts to be chronically elevated and especially when it starts to inhibit our ability to sleep well enough and long enough, okay?

So the point here is that when we embrace a stress enhancing mindset, we are able to have shorter duration release of cortisol. We are also able to engage what's called increased stroke volume under conditions of stress. This gets a little bit technical, but the amount of blood that your heart can pump with each beat turns out to be a key metric of stress.

When we are very stressed, even though we need to mobilize a lot of resources, somewhat paradoxically, our total stroke volume can actually be reduced. And we tend to shuttle blood and other resources towards the core of our body and towards major limbs and away from things like our brain and our periphery.

So one of the key measures of how a stress response quote unquote is going is how much peripheral blood flow there is. And when we are more relaxed under conditions of stress, there tends to be more peripheral blood flow. When we are more anxious, more panicked under conditions of stress, peripheral blood flow is lower.

And in a remarkable set of experiments, Ali Crum and colleagues have shown that when we are just taught that stress can be enhancing, and then we are placed into a stressful environment, either because we are imagining stress or we are experiencing real stress, and then our physiology is measured.

What is observed is that the total amount of blood that the heart can pump with each beat is actually increased, peripheral blood flow increases. And our ability to maintain cognition, to think clearly under conditions of stress increases. And again, the only manipulation here is a tutorial about how stress can be enhancing, which is essentially what I'm telling you right now.

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