The Science of Persuasion – Part One

Posted on January 31, 2015

Why won’t people listen? They’re so irrational! You make a sensible, even irrefutable political argument and they’re still not persuaded.

Cognitive science tells us that persuasion is hard. When deciding whether to agree with you, people rely on emotion and ingrained beliefs far more than facts. Indeed, if your listeners hold beliefs intensely, you’re probably wasting your time no matter how many facts you can muster.

There is science behind that stubbornness. Let us explore why people’s brains react this way and use the information to restructure our arguments to make them more effective.

Confirmation bias

Generally, political science (like economics) is based on the assumption that people mostly act rationally, that their political opinions and the way they vote are based on self-interest. But that’s unrealistic.

Everyone carries in their heads a long list of preexisting beliefs, stereotypes and biases. Democrats, Republicans and Independents hold on to those beliefs despite self-interest and in the face of facts.

All of us, consciously or unconsciously, are continually seeking out information that conforms to our pre-existing beliefs, while—inside our minds—ignoring or refuting any information that disproves those beliefs. It is an unwitting selective use of evidence in which we reinforce to ourselves what we already think.

This is called “confirmation bias” and scientists have known about it for centuries. As Sir Francis Bacon explained in 1620:

The human understanding when it has once adopted an opinion…draws all things else to support and agree with it. And though there be a greater number and weight of instances to be found on the other side, yet these it either neglects and despises, or else by some distinction sets aside and rejects, in order that by this great and pernicious predetermination the authority of its former conclusions may remain inviolate.

(For a detailed discussion, see “Confirmation Bias: A Ubiquitous Phenomenon In Many Guises.”)

Bacon was explaining that real science requires real objectivity. If someone approaches science with strong predispositions, s/he will never find the truth. The same can be said of politics and public policy.

What is the cognitive science behind confirmation bias?

Inside the brain

You are discussing politics with your Uncle Mort. And you say, “Voter fraud is virtually non-existent,” which is of course demonstrably true. The reticular activating system (RAS) in his brain, led by the amygdala [uh-MIG-duh-luh], instantaneously assesses the emotional value of your words. The RAS determines that these words are emotionally charged, so it diverts thinking away from the rational part of the brain, the cerebral cortex, and engages the limbic system, which is the more primitive part of the brain based on instinct.

Mort feels a strongly negative emotional reaction. Almost immediately, his brain’s hippocampus [hip-uh-KAM-puhs] helps retrieve memories that have been stored up to reinforce his pre-existing belief. So in his mind, it’s not just that he emotionally feels you are wrong; based on cherry-picked stored information, he factually “knows” you are wrong.

In fairness to Uncle Mort, it’s not just him. Everyone’s brain works the same way. When we process information, we first assess it emotionally and then compare what’s coming in to memories of past experiences and beliefs. This is not partisan, it is human. In order to survive, our ancestors needed a strong “fight or flight” reflex—the ability to react immediately without really thinking. We still do that.

Science writer Chris Mooney emphasizes that point in his excellent article “The Science of Why We Don’t Believe Science:”

…our positive or negative feelings about people, things, and ideas arise much more rapidly than our conscious thoughts, in a matter of milliseconds—fast enough to detect with an EEG device, but long before we’re aware of it. That shouldn’t be surprising: Evolution required us to react very quickly to stimuli in our environment.

As political activists, we wish that we could reason with people and have calm, cool, rational discussions about public policy. But instead, we tend to trigger in our listeners an emotional response reminding them of memories that reinforce the emotion. We are arguing with ghosts from our listeners’ pasts—and losing.

While everyone engages in some level of confirmation bias, it’s easier to demonstrate this in political partisans, both progressives and conservatives.

A psychological experiment

Clinical psychologist Drew Westen of Emory University used a functional MRI machine to examine what was going on in the brains of partisans who supported either George Bush or John Kerry during the 2004 presidential contest. He gave test subjects a series of openly contradictory statements from each candidate. Based on confirmation bias, it was expected that each partisan would overlook the contradictions of his or her own candidate while protesting indignantly the contradictions of the other guy. And just as Westen (and Sir Francis Bacon) would have expected, the test subjects did that, precisely.

When Westen looked at the MRIs, the subjects had not engaged the rational parts of their brains. They had engaged their emotions. And further, after relying on emotion to defend their candidate and attack their opponent, the brain’s pleasure center released the neurotransmitter dopamine in the nucleus accumbens [ac-CUM-bens]. As Westen explained in The Political Brain:

Once partisans had found a way to reason to false conclusions, not only did neural circuits involved in negative emotions turn off, but circuits involved in positive emotions turned on. The partisan brain didn’t seem satisfied in just feeling better. It worked overtime to feel good, activating reward circuits that give partisans a jolt of positive reinforcement for their biased reasoning. These reward circuits overlap substantially with those activated when drug addicts get their “fix,” giving new meaning to the term political junkie.

This means that when you challenge preexisting beliefs, not only are your arguments rejected, but you are also helping emotionally reward partisans for their stubbornness, deepening their attachment to false ideas.

What’s an honest progressive to do? We can be mindful of the part of this process that we control.

Negative triggers

You can structure your argument and choose words that are far less likely to trigger that instantaneous negative emotional response. You can even trigger positive rather than negative emotions in your listeners.

You might already have some awareness of emotional triggers or “hot buttons.” For example, you may realize that people who suffer from Post-Traumatic Stress Disorder (PTSD) have memories that are intensely painful to recall. Words, phrases, situations and even smells can trigger those memories and cause the PTSD patient to relive the agony.

On a much less dramatic scale, our brains respond to emotional triggers all the time. We react to all our senses, comparing current input to our past experiences. Emotional triggers are words or other stimuli that make people subconsciously remember positive or negative situations in their pasts and actually relive, to some extent, positive or negative emotions from the past. The reaction within us is automatic, and again, extremely quick.

Negative triggers impact us more powerfully than positive triggers. This is called “negativity bias” and it’s related to our ancestors’ need to respond quickly to danger. If you look at political messages, you will notice that negative arguments tend to work better than positive ones.

Part Two of this discussion will explain how to avoid negative emotional triggers that work against you and evoke instead some positive reactions. One tip is to begin any argument from a point of agreement with your audience. A second tip for avoiding negative triggers is a central part of Dale Carnegie’s advice in How to Win Friends and Influence People: if you want to persuade, don’t tell people they are wrong.