The Science Behind Persuasion

I distinctly remember my dad telling me that commercials couldn’t convince him to buy anything—he was a man immune to all marketing ploys and tactics.

Fast forward to my father buying BluBlockers. If you aren’t familiar with these aberrations, you are one

of the lucky ones.

Now if you were to ask my father, the commercials for these things had nothing to do with his purchase. Nope, he had this idea all by himself. He knew he needed sunglasses and just happened to pick these up.

Reminiscing about my dad’s love of infomercials got me thinking about persuasion. How does it work? Why does it work, and what purpose does it serve? We have to traverse the often murky waters of various persuasive techniques every day, so we may as well know a few things about it.

Persuasion is social

Persuasion is part of the way we communicate. Our social lives are immensely important to our very survival. It is part of why we take such great pains to be understood by others and to understand those around us.

You may not realize it, but the moment you enter a room your brain is already working out who the most popular people are. The brain does this instinctively because it knows that being around popular people is important for its ability to exert influence (be it social or otherwise) over others.

The brain uses two systems to help determine who the popular folks are:

  • The reward system: will this person be able to assist me in the future? What kind of return can I expect from maintaing or building this relationship?
  • Social cognition system: This is what helps us recognize the feelings, emotions, and intensions of others.

Why is this relevant?

This is the same system that helps us determine which ideas we like and want to spread, which is exactly what researchers at UCLA found.

In the study, researchers separated two groups of students into “interns” and “producers”. The interns watched a series TV pilots while their brains were scanned using functional magnetic resonance imaging (fMRI). After viewing the pilots, the interns had to record their recommendations for which pilot should be produced. These videos were then passed onto the student group of producers who made a decision on the TV pilots based only on the interns arguments.

Researchers found that there is something in the brain that activates when people find an idea worth sharing with others. It’s called the temporoparietal junction (TPJ) and it activates the moment you see something you want to pass on.

The interns who were most successful at persuading the producers were the ones who experienced the most activation in their TPJ. The TPJ is also part of the mentalizing network of the brain. That’s a fancy way of saying it’s your ability to think about the thoughts and feelings of others. The mentalizing network is also composed of the dorsomedial prefrontal cortex—which regulates choice behavior. The more these two regions were activated, the more successful the interns were at persuading others.

Persuasion isn’t only about what you find useful, it’s how you believe that information will be useful to others. Persuasion, has an extremely large social element that is wired deep with in our brains.

The expert effect

You know how you say to yourself, “Like I’m going to buy that stupid product just because some celebrity is shilling for it…”

Here’s one thing you can be cautiously optimistic of, if it didn’t work, marketers would not continue to do it. The celebrity expertise effect has been fairly well documented. But just how much does the expert effect influence us? The answer is a heck of a lot.

single exposure to an object + celebrity expert endorsement results in improved memory and more positive attitudes towards the object itself.

We are just more likely to believe people and trust their opinion if we believe they have relevant knowledge. Which is also why not all celebrity endorsements work, we have to actually perceive the individual relaying the message as an expert.

If Will Ferrel was going to talk to you about a comedy school you’d think, “Yah, that makes sense, he’s funny, he knows what he’s talking about, I trust his opinion.”

What we’re doing here is inferring their expertise on a product based on what we know about them as a celebrity. Though this can happen with anyone whom you view to be as an expert. The greater confidence you have in someone’s expertise, the more you trust them, the greater the chance you will be persuaded by their argument.

That old chestnut…

No discussion of persuasion can exist without discussing the Elaboration Likelihood Model (ELM). ELM says there are two different ways in which communication can persuade us and here they are:

Central processing: active/critical thinking that stems from our involvement with the message or if that message is contingent on a timeframe. You have to have the motivation and understanding of the message in order to do this kind of processing.

Peripheral processing: takes cues from other parts of the message which may not be directly related to the strength of the message itself. You can engage in peripheral processing without exerting a significant amount of mental energy which is why we use it so much of the time.

We use the ELM to help us process all of the messages we receive each day. Marketers know this, which is why they spend a good amount of money trying to appeal to both central and peripheral processing.

Say you are in the market for a new computer, you’ll be paying a lot of attention to the specs, the price—the important details. Still, retailers don’t want to exclude everyone else who isn’t immediately interested in purchasing a computer. They still want to attract other people and they do this by using prestige, credibility, and other peripheral cues.

There are also a few (million) other highly effective persuasive techniques that are employed to get you to behave or think about an item in a certain way.

Here are a few that you’ll be most likely to see:

It’s just lists, on lists, on lists

You see lists all the time. There are entire websites devoted to nothing but lists. That’s because they are infinitely effective at getting and maintaing your attention. The majority of us read via scanning in order to identify relevant information. Lists help us to locate information efficiently.

Sequential cues help us process information rapidly, it’s why lists are such a powerful persuasive tool. It appeals to the peripheral message processing that each of us do every single day.

  1. Lists enable me to repeat the same core message (whilst giving you the impression that I’m saying something different).
  2. Repetition is key to sending a persuasive message (see what I did there).
  3. It allows me to explain why in a concise manner (which is necessary for persuasion).

Variety is the spice of life and of persuasive messaging

People are more likely to be persuaded when they receive multiple persuasive messages from different social-groups. It’s not simply a numbers game.

Let’s say you are perusing Facebook and you see that 10 friends of yours are super amped about seeing the new X-Men movie. That’s okay but that is not likely to persuade you to see the movie. If, however, you saw a co-worker, a friend, and a family member all post about the movie…well, you’d be FAR more likely to see the movie.

This is about relatability. What is the likelihood that those around me are doing the same thing? If we believe that those around us are engaging in activity, we are far more likely to do it ourselves.

It’s not about you

I remember writing persuasive essays back in college thinking I was producing some real epic crap. I thought that being persuasive was about describing why something was important or relevant to me, but persuasion isn’t really about you at all. It’s about the person you are trying to connect with.

Messages that are highly tailored to the individual are the most likely to be persuasive. Highly successful persuasive campaigns activate an individuals self-reflection areas of the brain— the medial prefrontal cortex. Researchers can actually predict how effective a persuasive campaign will be based on how activated these areas of the brain are.

Here is what researchers found when they examined the brain scans of people exposed to a pro-sunscreen campaign:

“The stronger the activation in the medial prefrontal cortex, the more likely people were to use sunscreen two weeks after the study. Activity in this brain region was even better at predicting whether participants would use sunscreen than the participants’ own reports in interviews conducted immediately after the imaging.”—Matt Lieberman

How in the world do you incorporate this stuff into your actual daily life? Well, here’s how:


I’m not going to walk into a room, sit down and say, “So here’s how it’s going to be…” Unless I want everyone to dislike me immensely.

Successfully persuasive people watch first. They understand the dynamics of a group, how people interplay off of one another. They figure out what is missing and what they can contribute.

You have to consider your persuasive argument within the context of the space and time in which you are presenting it. What sounds good in the vacuum of our minds, doesn’t always translate to a crowded room full of people. The most persuasive people aren’t always the loudest. They are the ones who have fully considered their arguments and positions.


For the love of everything that is good in this Universe, stop talking and listen to people. Hear them out. Actually learn about their interests and concerns by asking questions. You can do this by responding in question form, this gives you a chance to learn and listen.

By building a rapport you increase the connection you have with the individual which helps increase the likelihood that your message will actually get through to them. Listening doesn’t just means you have one conversation with someone and then expect them to do your bidding for you for the rest of eternity. You have to actually do the work of establishing a sincere relationship.


People mistakenly assume that compromise means you lost but that’s not true at all. What compromise allows you to do is to show the other person (or group) that you actually value their contributions and place them within the same realm of importance as your own.

“When colleagues see that a persuader is eager to hear their views and willing to make changes in response to their needs and concerns, they respond very positively. They trust the persuader more and listen more attentively. They don’t fear being bowled over or manipulated.”—HBR

Comprising is about creating trust and a conciliatory environment. Ultimately, here’s what it comes down to: people don’t want you to tell them what to do or how to behave, they want to believe they came to this conclusion all by themselves.

The moment you begin to see or hear a message, your brain is already trying to figure out how it can use that message to influence others or to get some kind of future reward.

It’s not callous. The majority of us don’t try to persuade people because we are evil bastards. Persuasion is just another survival tool for us, it helps us engage in beneficial social activity which ensures our continued existence.

Also, if reading this can help you avoid purchasing ugly sunglasses than really this was all worth it.