KELLY MCEVERS, HOST:
For the past four weeks, we have watched a number of natural disasters unfold on the news.
(SOUNDBITE OF NEWS MONTAGE)
UNIDENTIFIED MAN #1: Harvey hit Texas with Old Testament wrath.
UNIDENTIFIED MAN #2: This morning, residents in the lower Keys stunned as they return home.
UNIDENTIFIED WOMAN: The needs are unprecedented in light of the scale of this hurricane.
UNIDENTIFIED MAN #3: After blasting neighboring Puerto Rico, where the damage is catastrophic.
UNIDENTIFIED MAN #4: Over 200 killed in Mexico in that 7.1-magnitude quake on Tuesday.
MCEVERS: Hurricanes, floods, earthquakes - experiencing these things of course is very difficult, but watching them from afar can also affect our mental health. With us now to talk about this is NPR social science correspondent Shankar Vedantam. He's also the host of NPR's Hidden Brain podcast. Welcome to the show.
SHANKAR VEDANTAM, BYLINE: Hi, Kelly.
MCEVERS: So we should start by making clear there's a big difference between directly witnessing or experiencing a disaster and watching it from a distance. What do we know about how people deal with trauma?
VEDANTAM: Well, perhaps the most important thing to start by saying is that human beings are remarkably resilient, Kelly. Lots of people go through disasters, and they come out OK. Now, some people of course are not so lucky. Post-traumatic stress disorder can produce intrusive thoughts or nightmares or flashbacks. It can be really debilitating. And the simplest way to distinguish is simply the passage of time. If symptoms persist beyond a few weeks, it's time to look for help.
MCEVERS: OK, so that's up for people who experienced the disaster. What about watching it from afar? How can that take a toll?
VEDANTAM: So here's the interesting thing, Kelly. The official criteria for post-traumatic stress disorder require direct exposure. But if you step away from whether something constitutes a diagnosable disorder to just the feeling of being traumatized, many more people are clearly affected.
You know, I remember, Kelly, after the 9/11 attacks, there were lots of people who were coming into therapists saying, I can't stop thinking about what happened. And these were people who were hundreds or thousands of miles away from the location of the attacks.
MCEVERS: Just watching it for hours and hours and hours on television.
MCEVERS: So why is it that a distant event like this can have such an effect on us?
VEDANTAM: You know, it might be helpful to step back and see the bigger picture for a moment. For nearly all of human history, people had no idea about stuff happening in another part of the world. So it would have taken days or weeks in the 18th or 19th century for someone in California to hear about an earthquake in Mexico. For most of our evolutionary history, in other words, if you heard or saw something bad, it was because that bad thing was happening right next to you. Now, in recent decades, we've changed that. We can now hear and see things that are happening in faraway places. And with radio on television, you can feel as if you are actually right in the area that is being devastated by a hurricane.
Now, of course people sitting in Maine or Michigan do consciously know that they are not in harm's way when they are watching television about a hurricane that's striking Florida or Texas. But there are still ancient algorithms in the brain that tell us if we can see and hear something terrible happening, it's probably because that terrible thing is happening right next to us.
MCEVERS: So then (laughter), you know, with all the information we have access to today, how much is too much then? I mean is there a thinking among scientists that we should cut back?
VEDANTAM: I think that actually is one of the most regular pieces of guidelines we get before every natural disaster. The question that might be worth asking is, what do you need to stay informed? It's important to keep up with the news of course, but do you actually need to watch seven straight hours of hurricane coverage if you're not directly affected - probably not.
MCEVERS: But we do want to stay informed, and we do want to stay compassionate. That's a reason we watch the news - right? - is because we feel empathy for people going through this stuff. How to do that and also protect our own mental health?
VEDANTAM: I actually think the two things go hand-in-hand, Kelly. You're going to be more effective, and in fact you're probably going to be able to do more if you keep up with the news without feeling like you yourself are in the midst of the disaster. In fact I would argue that overexposure makes things worse. If you felt traumatized watching all the coverage of Hurricane Irma, chances are that you're going to pull the blanket over your head when it comes to Hurricane Maria. You're just going to say, stop; I just can't take this anymore.
MCEVERS: So when you have those feelings, notice them. Be aware of them, and try to regulate them, yeah.
MCEVERS: NPR social science correspondent Shankar Vedantam - you can hear him every week on NPR's Hidden Brain podcast. Thank you very much.
VEDANTAM: Thanks, Kelly. Transcript provided by NPR, Copyright NPR.