Why do we experience stress?

Presenter: So why do we experience stress? Our body is an amazing machine where everything happens for a reason. If it's there, it's because it serves some purpose. So what is it? Well, actually, what pain is to our body, stress is to our mind. It's an alarm signal. Just like with pain, the message is simple: Warning: Danger. From a brain's perspective, it's the part of our brain that is responsible for our survival that gets activated. Our limbic amygdala takes the lead role as it evaluates situations and orchestrates suitable reactions. In a world where wolves, bears, and other predators were freely walking the earth, this part of the brain makes a difference between life or death. When faced with a potential threat, the limbic amygdala sends out signals to other parts of the brain to come up with the most appropriate survival strategy, triggering all kinds of physiological responses to maximize a positive outcome. When faced with a potential threat, the amygdala sends a signal to the brainstem who's in charge with breeding heart rate, blood pressure, and so on, saying, "Look, I will need all the available resources to get me out of this situation alive." At the same time, the amygdala signals the prefrontal brain, where irrational thinking occurs, basically telling him, "Look, there's no need to overanalyze this situation right now, so just go with whatever I'll tell you and shut up." Imagine, just for the sake of argument, that this huge lion identified you as its next meal and starts chasing you. The amygdala says, "Run!" Now, your prefrontal brain goes, "Hold on. Wait a second. Where do you wanna go? If we go to the right, we could make it to this waterhole. But then again, lions, even though they don't like water, are actually good swimmers so they could follow us. On the other hand, if we go to the left, there's this big tree that might offer an option. However, from here, I'm not quite sure we will be able to climb into it by ourselves. So maybe it could be interesting to look into a third option." By this time, the lion has already eaten out your liver as an appetizer and is texting his buddies to come over and join him for the main course. Also, the amygdala signals the hippocampus, responsible to lay down memories, so that next time you see a lion, the information is processed much quicker and your survival chances go up. Last but not least, the amygdala signals the hypothalamus who's in charge of regulating a whole bunch of hormones, but will dive into that in the next lecture. So the brainstem activates the available resources to react to the threat at hand in three different ways. What follows are three different survival strategies. The first one is to flee; run for your life. In order to do so, the brainstem will send out a message to pump more blood towards our legs so the muscles get more oxygen and we can run faster, hopefully, outrunning danger. The second survival strategy is to fight. If the opponent is of a fair-size compared to us, it might be an option to hold the ground and face the enemy. Now, this doesn't mean that we will necessarily fight as we can win just by intimidating our enemy. Still, on a physiological level, blood will be rushed, not towards the legs this time as with the fleeing strategy, but towards our arms and hands to be able to punch and claw as well as to our jaws as to bite and tear our opponent apart. Most people are already familiar with these fight or flight strategy. However, there is a third one that evolution gave us, and that is to freeze. Basically, we will try to make ourselves as small as possible so that the predator might overlook us or even consider that we're not interesting enough as a prey. To do so, the brainstem will not accelerate our heart rate as with the two form strategies, but on the contrary, we'll slow it down. Energy levels will drop and our whole body will slow down. This way, hopefully, the predator will overlook us and we will have successfully live through another day. So here they are, the three survival strategies: We can flee, fight, or freeze. Lucky for us, there are not that many packs of wolf or hungry grizzly bears walking around in our modern cities. Yes, of course, our lives can still be threatened when crossing a street or if we're unlucky enough to get mugged, and the amygdala will respond accordingly, making us run faster, intimidate our aggressor, use a submissive strategy as not to get hurt, or call upon groups solidarity. The thing is, our amygdala also gets activated when our life is not in danger. It gets triggered when faced with a perceived danger, which could be actually anything. We're probably the only species on earth that is capable of worrying about something that might never happen. So whenever we face a perceived danger, which doesn't have to be life threatening, by the way, the amygdala will activate and will make us feel something that has become widespread in our modern lives. We will feel stress. And yes, the three original survival strategies live on in our modern day stress reactions. We will still flee, fight, and freeze. Let me show you how. Instead of having a huge grizzly bear standing in front of us, it could be our boss or our partner, or maybe we're just stuck in a traffic jam. So how do we flee, fight, and freeze? When the amygdala goes for the first strategy, our main objective is trying to escape. We want to get out of there. We will feel anxiety overwhelming us. Our overall attitude is the desire to be somewhere else. So how does it show? Fleeing is all about movement. So our hands might start shaking. If we sit down, our feet will move. Our fingers will start playing with a pen or touching a ring. We'll feel the need to go to the bathroom even if we already went three times in the last five minutes. Stage fright is a perfect example of flee stress. We might feel tension in the legs. Our voice could become unstable. We could even have palpitations. By now, our head is probably a mess, incapable of thinking straight and confusion all around. At night, insomnia is common. All this is nothing else than our brainstem telling us, "Run, buddy. Run for your life." When the amygdala goes for the fighting option, our objective is to intimidate. We're becoming aggressive, yes, but it's a defensive aggression. Overall, we get a feeling of superiority. We're able to crush the thread at hand if need be. So how does it show? Try to remember an argument you might have had recently. Fighting is all about power, so tension will start to build up. It's an overall tension with a particular focus on the neck, arms, and jaw. Our voice will be louder and more articulated. Movements will become stronger as well. In those moments, we have absolutely no patience whatsoever. Our eyes will not let go of the target. Squinting even slightly is common. It helps to focus on our target. We are in fight mode. And if we need to land some punches, they better hit our opponent. The third way of expressing stress is through the freeze strategy. In freeze mode, our objective is to search for protection. We're not feeling capable of dealing with this situation at hand by ourselves so we feel demoralized. The overall attitude is one of helplessness. We can't do this alone. We need help. So how does it show? Freezing is all about vulnerability. Our body is slowing down. We will have a lower voice, talk slower, even use less words. Crying is common. Our overall energy level will hit rock bottom. We'll feel tired, extremely tired. We might even feel oppressed, having difficulties breathing. Yeah, at this point, well, you shouldn't really worry. You're just stressed out. Your brainstem is in control now. So here they are, our three stress reactions to a perceived danger. Depending on the situation, our amygdala will pick one out. So every one of us ends up showing the three stress reactions, even though most of us have something like a preferred stress response. Which one is yours? Do you know? Well, why don't you find out? Next lecture is a small test which will help you determine what strategy your amygdala favors. Do you flee, fight, or freeze?