Contagious: Why Things Catch On

by Jonah Berger

when we talk to others, we’re not only communicating information; we’re also saying something about ourselves.

When we rave about a new foreign film or express disappointment with the Thai restaurant around the corner, we’re demonstrating our cultural and culinary knowledge and taste.

Since we want others to think we’re interesting, we search for interestin...

Interesting products didn’t receive any more word of mouth than boring ones.

No correlation between levels of interest, novelty, or surprise and the number of times people talked about the products.

Imagine you’ve just gotten an e-mail about a new recycling initiative. Do you talk about it with your coworkers later that day? Mention it to your spouse that weekend? If so, you’re engaging in immediate word of mouth.

Ongoing word of mouth, in contrast, covers the conversations you have in the weeks and months that follow. The movies you saw last month or a vacation you took last year.

Movies depend on immediate word of mouth.

For most products or ideas, however, ongoing word of mouth is also important. Antibullying campaigns not only want to get students talking right after the campaign is introduced, they want them to keep spreading the word until bullying is eradicated.

But interesting products did not sustain high levels of word-of-mouth activity over time.

At any given moment, some thoughts are more top of mind, or accessible, than others.

Triggers are like little environmental reminders for related concepts and ideas.

Could voting in a church lead people to think more negatively about abortion or gay marriage? Could voting in a school lead people to support education funding?

firehouse). A significantly higher percentage of the people who voted in schools were in favor of increasing funding for schools. The fact that they were in a school when they voted triggered more school-friendly behavior.

Most conversations can be described as small talk.

We don’t want to sit there silently, so we talk about something. Anything. Our goal isn’t necessarily to prove that we are interesting, funny, or intelligent. We just want to say something to keep the conversation going. Anything to prove that we’re not terrible conversationalists.

So what do we talk about? Whatever is top of mind is a good place to start. If something is accessible, it’s usually relevant to the situation at hand. Did you read about the new bridge construction? What did you think about the game last night?

Furthermore, not only did triggered products get more immediate word

Ziploc bags may be boring, but they get mentioned week in and week out because they are frequently triggered. By acting as reminders, triggers not only get people talking, they keep them talking. Top of mind means tip of tongue.

But as we saw in our fruits and vegetables study, a strong trigger can be much more effective than a catchy slogan. Even though they

hated the slogan, college students ate more fruits and vegetables when cafeteria trays triggered reminders of the health benefits.

So while students may agree with the message when they read it, unless they are triggered to think about it when they are actually drinking, the message is unlikely to change behavior.

But for books by new or relatively unknown authors, negative reviews increased sales by 45 percent. A

Even a bad review or negative word of mouth can increase sales if it informs or reminds people that the product or idea exists.

But coffee is a particularly good thing to link the brand to because it is a frequent stimulus in the environment.

Products and ideas also have habitats, or sets of triggers that cause

people to think about them. Take hot dogs. Barbecues, summertime, baseball games, and even wiener dogs (dachshunds) are just a few of the triggers that make up the habitat for hot dogs.

message, the message that grew the habitat (by associating Boston Market with dinner) increased word of mouth by 20 percent among people who previously had associated the brand only with lunch. Growing the habitat boosted buzz.

Competitors can even be used as a trigger.

“Bob, I’ve got emphysema.” So now whenever people see a Marlboro ad, it triggers them to think about the antismoking message.

Researchers call this strategy the poison parasite because it slyly injects “poison” (your message) into a rival’s message by making it a trigger for your own.

As we discussed, one key factor is how frequently the stimulus occurs.

But this proved ineffective because the chosen stimuli—holidays—don’t happen that often. So Anheuser-Busch revised the slogan to “Weekends are made for Michelob,” which was much more successful.

The more things a given cue is associated with, the weaker any given association. It’s like poking a hole in the bottom of a paper cup filled with water. If you poke just one hole, a strong stream of water will gush out. But poke more holes, and the pressure of the stream from each opening lessens. Poke too many holes and you’ll get barely a trickle from each.

Linking a product or idea with a stimulus that is already associated with many things isn’t as effective as forging a fresher, more original link.

But there’s only one problem. I can’t buy a bath mat in a bathroom. The message is physically removed from the desired behavior. Unless I leave the bathroom, turn on my laptop, and buy a mat online, I have to remember the message until I get to a store.

So the DOH made a video showing someone opening what seems like a normal soda can. But when he starts to pour it into a glass, out spills fat. Blob after blob of white, chunky fat. The guy picks the glass up and knocks the fat back just as one would a regular soda—chunks and all.

Unlike the bath mat ad, its video triggered the message (don’t consume sugary drinks) at precisely the right time: when people are thinking of drinking a soda.

As a result, most-shared lists have a powerful ability to shape public discourse. If an article about financial reform happens to make the list, while one about environmental reform barely falls short, that initially small difference in interest can quickly become magnified.

For something to go viral, lots of people have to pass along the same piece of content at around the same time.

Okay, so sports articles are less viral than dining articles. But why?

Practical Value chapter, sharing useful information helps others and makes the sharer look good in the process.

Awe-inspiring articles were 30 percent more likely to make the Most E-Mailed list.

The most obvious difference between different emotions is their pleasantness or positivity. Awe is relatively pleasant, while sadness is unpleasant. Might positive emotions increase sharing, but negative emotions decrease it?

The answer was definitive: positive articles were more likely to be highly shared than negative ones.

Articles that evoked anger or anxiety were more likely to make the Most E-Mailed list.

Understanding arousal helps integrate the different results we had found so far. Anger and anxiety lead people to share because, like awe, they are high-arousal emotions. They kindle the fire, activate people, and drive them to take action. Arousal is also one reason funny things get shared.

Low-arousal emotions, however, like sadness, decrease sharing.

People think that if they just lay out the facts in a clear and concise way, it will tip the scales. Their audience will pay attention, weigh the information, and act accordingly.

Rather than harping on features or facts, we need to focus on feelings; the underlying emotions that motivate people to action.