We all have ideas about how we're going to behave in a crisis or emergency. It's almost never how things actually go. What you learn in a real disaster is that you have another personality, a disaster personality, and it's helpful to understand it better before you need it.

So if you look at human behavior across all different kinds of disasters across all of history, you see a huge spectrum of responses. Sometimes people start hysterically screaming. (Marion screaming) Other times, people shut down. They freeze.

Believe it or not, people laugh in the face of a life-or-death situation. Maybe most often, people carry on doing whatever they were doing before, and sometimes people rise to the occasion and do incredible things. They're heroes who lead hundreds of people out of mayhem,

who save lives at great personal risk. And it's really hard to predict, just looking at the person, how they're going to behave. For my book, "The Unthinkable," I followed people who had survived really hellacious disasters of all kinds,

and what you find is there's a pattern, even across very different contexts, from plane crashes to earthquakes. Almost always, people go through a period of denial, profound disbelief, and delay. Then people go through a period of deliberation.

People get really social. They do something that researchers call milling, where they discuss with each other what's happening and what they should do next. And finally, is the decisive moment, where people either take action or flee or cooperate in some way.

Or, most often, shut down and do nothing at all. Denial. Just the other day, I was walking through Dupont Circle in Washington, D.C., and I heard a gun go off around four o'clock in the afternoon on a random Tuesday.

(gunfire booms) It was very close. I could tell it was like a block away. I looked around, and nobody reacted. Everybody in that neighborhood, where there aren't a lot of shootings, kept walking as if it didn't happen.

People were on their phones. They were talking to their friends. They were drinking their coffee, and I was like, "What?" And then I remembered that, of course, people don't expect this to happen here, so they're acting like it didn't happen.

There's something called normalcy bias, which you see in all kinds of disaster situations, where people tend to think, "Whatever is happening, it's going to be fine." Our brains take whatever input we get and compare it to what we've experienced before.

So every firefighter has a story like this, where they come into a bar or restaurant, and there's smoke filling the ceiling. And the fire alarms are going off, and nobody's moving. Everybody's still, you know, drinking their drinks

and acting like it's not happening. This is very, very typical, especially for people who either have no training for emergencies, which is most of us, or who have never been in a life-or-death situation like that.  Deliberation.

One of the disasters I spent a long time studying was the evacuation of the World Trade Center on 9/11, partly because we have incredible research and survey data on the thousands of people who evacuated that day. And what you find is that, on average,

people took about six minutes before they even began evacuating. People took the time to gather books they were reading, shut down their computers before they left. But most of all, the first thing people did was to talk to each other,

and we've all experienced this, right? I mean, you've probably been in a situation where a smoke detector goes off. The first thing you do is you look around to see what everybody else is doing, right? That's a very natural reaction.

But deliberation is really helpful in a lot of cases because it's kind of like the wisdom of the crowd. If you have people around you who know things that you don't know, then you can make better decisions. It's a good survival response

if the people around you know anything about how to get out of the building or what might be the actual threat. One of the things that people are often surprised by is how social disasters can be. Typically, people become much more polite and considerate than they normally are,

which is the opposite of what we might expect. One of the reasons the evacuation took so long is that people who were evacuating from the upper floors would let the people coming in below them go first. On average, the World Trade Center evacuation took

About a minute per floor, which was twice as long as safety engineers predicted, even though the buildings were only half full at the time. And part of that was because of delay and denial, but also because of deliberation.

The decisive moment. This is where everything that's happened before in the denial, delay, and deliberation phases comes home to roost. For example, most serious plane crashes are actually survivable, which is surprising, but it turns out that most planes, if they crash,

they end up on the ground and on fire, and the whole trick is to get out really fast. But those delay and deliberation phases can really slow you down. There was a famous plane crash in Tenerife, Canary Islands, years ago,

and what they found is that even though people could have gotten off the plane, they actually died there from smoke inhalation from the fire. Many of them were found sitting in their seats. So there was a lot of research done

about why this happened, and what you find is that humans, like most mammals, tend to shut down in really frightening situations for which they have no training or prior experience. Researchers call it 'negative panic.' People do nothing.

They shut down, which is actually a good survival response in certain situations, but not in a plane crash. So that decisive moment is the culmination of everything that's come before. But there was one gentleman on that plane who, before the plane even took off,

He looked around and noticed where the exits were, which is what people who study plane crashes always do. He knew exactly how many rows away the exits were, and he had a mental model for how to get out of the plane.

So when the crash occurred, he grabbed his wife's hand—who was, at that point, kind of frozen, paralyzed—and he said, "We're getting out of here." They got off, and they survived. The people sitting around them did not.

One of the tricky things about fear is that it's super helpful in small doses, but when you have too much of an injection of stress hormones, like cortisol, you start to deteriorate. You lose eye-hand coordination. You lose your peripheral vision.

It feels like time slows down. The brain is trying to help you under extreme stress, but unless you've had some really good, realistic training, it tends to become counterproductive—like it's too much stress. So your eyes, your brain will fixate

on the perceived threat, which may or may not be the full threat. It's a really tricky, slippery slope. In any kind of disaster, fear is useful, but not too much. So people who tend to do better in disasters are people

who have had some training or some rehearsal beforehand. So, in the case of the gentleman on the Tenerife flight, he had actually been in a house fire as a child. So he knew how quickly smoke can fill a space.

and that the real threat in most fires is smoke. So that experience helped him push through the denial phase more quickly. So that's the decisive moment where your past experience, who you're with, right, how long you're stuck in denial,

all of those things really shape what you do or don't do. A lot of our survival instincts don't serve us very well in the modern world. The good news is you can actually evolve on purpose through realistic training. So the better you understand your environment

and the risks that you face, and the more prepared you are for some of the problems you might encounter, especially denial and delay, the better you can push through those phases and make an intelligent decision under stress. We are capable of incredible things,

but we have to respect regular people enough to help them be agents of their own destiny. We have to trust them to do the right thing but give them the information in advance. The biggest mistake I've seen in every disaster I've ever covered

is that the people in charge do not trust the public. They think that the public is going to panic, misbehave, do stupid things, and so they don't tell them the full truth, which leads the public to sometimes do unwise things.

That problem is bigger than most of the threats we face. The fear of panic has killed more people than most disasters themselves.  Want to dive deeper? Become a Big Think member and join our members-only community. Watch videos early and unlock full interviews.

Prime your mind for disaster — while you’re still in control | Amanda Ripley

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Big Think

Unexpected Disaster Personalities and Reactions

Individuals' planned crisis behavior rarely matches reality; disasters reveal a distinct 'disaster personality'.

Responses vary widely: hysteria, freezing, laughter, or continuing normal activities.

Some display heroism, while others' reactions are unpredictable.

Research on various disasters reveals patterns in human behavior.

Initial denial and disbelief followed by a period of deliberation.

Social interaction ('milling') to discuss the situation and plan next steps.

Example of denial: lack of reaction to a gunshot in a normally safe area.

Normalcy bias: tendency to believe things will be fine, even in dangerous situations.

Example of normalcy bias: people ignoring smoke and fire alarms in a bar.

Deliberation and Social Dynamics in Disasters

World Trade Center evacuation study shows an average of six minutes before evacuation began.

People prioritize social interaction, observing others' reactions.

Deliberation leverages the 'wisdom of the crowd' for better decision-making.

Increased politeness and consideration are common during disasters.

World Trade Center evacuation took longer due to delay, denial, and deliberation.

Many plane crashes are survivable, but delays hinder escape.

Tenerife plane crash example: people died from smoke inhalation due to inaction.

'Negative panic': shutdown response in frightening situations without prior experience.

A passenger's prior experience with fire enabled quick reaction and survival.

Fear is helpful in moderation, but excessive stress impairs coordination and judgment.

Prior training and experience improve performance under stress.

Past experiences shape reactions; the passenger's childhood fire experience aided his response.

Past experience, social context, and duration of denial influence actions.

Realistic training improves responses by addressing denial and delay.

Empowering individuals through information and preparation is crucial.

Mistrust of the public by authorities hinders effective disaster response.

Fear of panic causes more harm than many disasters themselves.