THE BLOG
01/02/2014 07:01 pm ET Updated Mar 04, 2014

Yielding to Neural Temptation

Andrew Bret Wallis via Getty Images

The personally tailored sponsored ads we receive daily on our computers are rather convenient. A delivery boy bringing the newspaper to our doorstep with all the relevant ads already circled could almost match the experience. In a Hitchcock-like movie, newspaper ads would slowly creep into your house. As you sit on the sofa, an ad would instantly place itself under the palm of your hand. On one unfortunate occasion, you take a peek at it, and now it is devotedly following you around. Internet advertising reality is not that far from having a newspaper ad for a stalker. A friend confessed to me a few days ago that she owns "more than one pair of shoes that chased me around until I couldn't resist." When the distance between the tips of our fingers to an ad is so small, do we really make a choice when responding to it? Brain research suggests the opposite: The ad chooses us.

We feel uncomfortable learning that websites aggregate, profile, personalize and sell our information to third parties, but it takes us five minutes to get used to it. Mind reading has always been the most efficient way to communicate, and it feels just like it, when the shoes we were just thinking about appear in front of our eyes. Instead of us digging up information, information presents itself to us effortlessly. All we need is to choose, which we evidently do, or at least we believe we do.

Neuroscience researchers have a fairly good idea of how the brain reacts to stimuli imbued with motivational salience (such as ads, gift wraps, trademarks, warning signs, lottery cards, etc.) that signify outcomes of high value (such as a prizes, food, money, threats, etc.). A group of deep structures in the brain -- the basal ganglia -- is responsible for translating the information that motivational stimuli convey into choice. The basal ganglia mediate this process by forming an emotion-motor interface where reactions to motivating stimuli could guide actions. In a typical laboratory experiment, a rat learns to press a lever in order to drop food pellets into the food cup. The rat also learns, in a separate session, that whenever a stimulus such as a red light appears, food will drop into the cup. The interesting thing happens when the red light is turned on while the rat is pressing the lever: The rat begins to press it more vigorously. This is not very efficient on the rat's part. Each lever press delivers one food pellet, and pressing harder would not change the amount of food dropped into the cup, so why waste energy?

A study by Talmi and colleagues showed that people behave in much the same way as rats in the presence of motivational stimuli. Their study participants squeezed a handgrip in order to obtain money, and did it with greater vigor in the presence of money-related stimuli. This tells us that certain stimuli can invigorate our goal-directed actions just because they signal the same goal. If you have several goals in mind but can perform only one action at a given moment, what determines the action that would ultimately be chosen? We would like to think it is our ability to prioritize, but it could be something mundane as the little shoe image that appeared briefly at the corner of the screen, invigorating the must-buy-shoe-now action. Had it been a different image, you would have planned your vacation at the Bahamas right now. Why might these efficient "reminders" for things we had on our mind anyway be problematic? The problem is that these salient stimuli do not only invigorate our actions; they also take control of the brain processing of our thoughts.

In a study we performed in my lab, published recently in the journal Neuron, we examined the brain's reaction to such motivational stimuli. Instead of performing a real action, though, we asked the participants just to imagine the action. This type of motor imagery, such as picturing yourself throwing a ball, activates not only imagery networks but also motor regions that mediate real actions. The participants earned money for their imagery, which we tracked by measuring their brain responses in real time. In a separate session they also learned that a certain visual stimulus (such as a checkered square) signified winning money. This allowed us to create a laboratory experience that mimics your sitting by the computer, thinking of things you need to do, buy, or plan, when an ad appears on the screen. Here, we asked the participants to imagine that they were doing an action that would result in earning money, while the money-related visual stimulus appeared on the screen. Two interesting things happened in their brains.

First, we observed a boost in the neural responses of the motor imagery network. Second, the reward system of the brain, which encodes the value of the money-related stimuli, began working in coordination with the motor cortex. This neural synchronization between the "value" and "action" systems of the brain might be the gateway through which motivational stimuli act on our behavior. The motor cortex is the part of the brain that is in charge of commanding our body to perform actions. But here we engage it just by imagining an action we would have liked to perform. If the money-signaling stimulus appears while we imagine an action, the motor cortex receives a motivational cue from the reward system, and the two systems coordinate their function. This in turn could guide action selection, and determine which particular action we should execute.

Fast-forward into the future. Picture yourself sitting by your computer. Ads are appearing on the screen, and your thoughts are running in different directions. I am standing behind you, holding a device that measures your brain activation. By observing the cascade of events that each ad triggers in your brain, I could tell which action you are going to perform before you actually perform it, maybe even before you are aware of it. Neuro-marketing companies would use the technology to identify the most effective ads, and which "teasers" they should plug in to stir your thoughts in a certain way. The more you obsess about something, the higher the chances of those ads causing the inevitable. Even if you try, just by exposing yourself to ads, you increase your chances of relapse.

You believe you bought those shoes because you made up your mind, but given the neural chain of events, someone else probably made up your mind for you. The ads are there to tempt your neurons to fire in a certain way. They pave the path of your moment-to-moment decisions. This is how motivational stimuli, or advertising, works. We are surrounded by it every day. But when it is personally tailored to our brain, our free will shrinks more effectively, placing us in the path to zombiness.

There is nothing much to do about it now except avoiding ads, clearing browsing data, and trying not to think. The technology is there, and we want to stay connected. But now that we know how it works in our brain, we have a choice. We can honestly say that we choose to be manipulated.