The persuaded brain

Know then thyself

Presume not God to scan

The proper study of mankind is Man. — from Essay on Man by Alexander Pope (1688-1734)

If Alexander Pope lived today, he would have been a guru to advertising agencies. The verse above has been adapted in so many PowerPoint versions as the whole marketing and promotions industry try to anchor their strategies around studies on human behavior by observation and/or focus groups. But it is not just advertising groups who need to persuade us to buy goods or services. Other groups who communicate to sway also have to rely on what we know so far on how we can persuade humans to act, to seek help, to get information, to recycle, to conserve, and even to care. Name it, we are all trying to send out messages out there to persuade the rest of us to do something. But whatever your goal is when you play the art of persuasion, you may now complete your persuasion kit by knowing the neuroscience behind it.   

Touch the space between your eyebrows. Right there, behind your skull is a part of your brain that carries out plans different from that you have decided on. It is the part whose activity that indicates if you have been persuaded. It is called the medial prefrontal cortex and it behaves in a creepy way.

The study claims to be the “first functional magnetic resonance imaging study to demonstrate that a neural signal can predict complex real world behavior days in advance.” In other words, it can predict behavior by simply looking at present brain scans. It has caused a stir in science news and it appeared in Journal of Neuroscience last June 23 entitled “Predicting Persuasion-Induced Behavior Change from the Brain.” It was already amazing enough that neuroscientists were able to predict the behavior of the subjects based on the scans of their brains. But what was even more fascinating and creepy in a sense was that the scientists were able to predict it better than the subjects themselves who, well, were in possession of these very brains in their heads.

The experiment had 10 males and 10 females watch a public health ad on the importance of using sunscreens while they were hooked on to brain scanning machines that monitored increased blood flow in parts of the brain. This is called an fMRI machine (functional Magnetic Resonance Imaging) and it enables scientists to witness your brain in motion. This is called a “neural focus group” which looks at the brains of the subjects as they are exposed to stimuli, as opposed to the usual focus groups which rely on verbal and written responses of subjects to a topic.

After the subjects viewed the ads while hooked on brain scanning machines, the subjects answered a questionnaire on whether they would use sunscreen. A week passed and the researchers called the subjects and asked them how often they used sunscreen during the week. Then they compared the self-reported intentions of the subjects a week ago and the scientists’ prediction. It turned out that the scientists’ prediction of how often they would use sunscreen was far better than what the subjects reported in the questionnaire right after their scans.

The scientists who did the study were Emily B. Falk, Elliot T. Berkman, Traci Mann, Brittany Harrison, and Matthew D. Lieberman, from the University of California in Los Angeles and the University of Minnesota. They were able to predict behavior because they banked on what excites the medial prefrontal cortex. These are events or objects that arouse critical thinking and self-awareness, not to mention your own desires and “disgusts.” This is your brain part that just gets so full of itself when it senses that something it is witnessing connects to “me, myself and I”. They suspect that if there is increased activity in this area, then it is more likely that you have been persuaded by what you have just seen (such as an ad), regardless of what you decide on right after seeing the ad. Imagine, by looking at our brain scans, they could know better than we can ourselves. That is why it is, as I said, quite creepy.

It is also eerie in another sense — in that sense that we have always known about ourselves. That we are “many.” That every moment, we are always torn between our many selves — the self that seeks safety and comfort and the self that yearns for adventure, the one that likes ice cream and the one that counts calories, the one that wants to let go and the one who needs to control. And these selves are like ghost carousel items taking turns to seize the center of our being each day. And science is telling us that there are brain parts and connections that have a hold on these carousel items far more than we are aware of.   

Over 300 years ago, Alexander Pope did summon us to understand ourselves more by studying ourselves and each other. I write back to him now in a parallel verse:

You think you know yourself

Until you see your scan

Alas, the winning bet of the future is not yours but the scan’s.

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