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Do You Really Know Why You Do The Things You Do?

Recent research reveals how deliberate decision making is an illusion.

David Kovalenko/Unsplash
Most of our decision-making happens under the radar, but we feel we are in control of our decisions
Source: David Kovalenko/Unsplash

What would it be like if animals could tell us why they do the things they do? Some of their behavior certainly calls for an explanation. Roller dung beetles, for instance, attracted recent attention for a peculiar behavior: While rolling their dung ball, they periodically stop and climb on top of it and perform a ritualistic dance before carrying on. This seemed odd even for an animal that makes balls out of manure, so scientists recently conducted studies to understand it. It turns out that the climbing and the dancing is likely for navigation or cooling their feet—or both. Would solving the puzzle be easier if the researchers could ask the beetles themselves?

Thankfully we can ask people about their motives, but is asking really helpful? People often conceal the truth (as in, “I’m breaking up with you because I need to spend more time with my dog”) but there is a more fundamental problem. Most people think that they know how they arrive at a decision, but they don’t.

Without our knowledge, our minds often steer us in particular directions. We tend to think that we make deliberate and calculated decisions especially on matters of personal importance such as where we choose to live, what profession we choose, and how we spend or invest our money; but the reality is different. For instance, it turns out that people have a preference for living in a city or a state whose name resembles theirs. Data suggests that someone named Dennis is more likely to choose to live in Denver than a similar person with an unrelated name would be. The same is true for Mildreds in Milwaukee, Jacks in Jacksonville, Philips in Philadelphia, Florences in Florida, Georges in Georgia, and Louises in Louisiana. It turns out that there is a similar kind of preference for what people do for a living, so someone named Dennis is more likely to become a dentist than is a similar person with an unrelated name.

Stock market data suggests that investors initially prefer stocks whose names they can easily pronounce. For a period after the initial public offering, the shares of a company with a name that is easy to say such as Barnings Incorporated outperforms the shares of a company with a name such as Aegeadux Incorporated.

Behavioral data shows that a price that we accidentally consider before a purchase influences how much we end up paying. It doesn’t matter that the buyer knows that the initial amount is completely arbitrary. In one experiment, people were first asked to consider whether they would pay the dollar amount corresponding to the last two digits of their social security number (an arbitrary number) for an ordinary purchase. For instance, someone with an SSN ending with 12 considered paying $12 for a particular bottle of wine. Subsequently, those with higher-ending SSNs ended up bidding higher amounts in an auction for the item.

People would deny being influenced by their name’s resemblance to the word for a profession or the random number that they just considered for a purchase. In fact many people find the suggestion an insult to their intellect (“other people might get influenced, but I certainly don’t”). This confidence is rooted in the hidden nature of the mental processes that take these factors as inputs and our mind’s ability to present to us, in a seamless fashion, our behavior as a consequence of conscious decisions.

This point is illustrated by a series of fascinating studies with split-brain patients, people whose left and right brains are disconnected. Each hemisphere of the brain can process information and make decisions on its own. This can create conflicts when left and right brains are unable to exchange information and each hemisphere receives different information. Given that the left brain is responsible for producing speech, what happens when the patient is asked to explain behavior caused by the right brain? The left brain observes the behavior but cannot know the reason because, in split-brain patients, it doesn’t receive information from the right brain. The researchers created such a situation by showing the picture of a snowstorm to the right brain (via the left eye) and a chicken to the left brain (via the right eye). When the patient was asked to point to a related picture, the right brain (controlling the left arm) correctly pointed to a snow shovel and the left brain (with the right arm) pointed to a chicken foot. Remarkably, however, the patient explained that he pointed to the shovel because the shovel cleans the chicken shed. This is the left brain making sense of the situation with the only information it has access to (seeing a chicken and pointing to a shovel). It is post-decision rationalization in action, and it is common in ordinary people’s daily decisions.

It has been known for a while that by monitoring brain activity it is possible to predict a decision before the person has any conscious experience of making one. More recent research revealed that decisions could be detected this way up to 10 seconds before they are consciously made. What we experience as decision making then is merely creating a justification for a decision that was already made unconsciously.

The concealed nature of our decision-making processes leaves much to be discovered and this makes research in this area dynamic and exciting. The countless decisions that we make—our college major, whether to rent or buy, start or end a relationship, watch this or that show on Netflix, quit a job or keep going, spend or save, walk or drive—are driven by a sea of forces that operate under the radar in our minds. Most people would agree that there is room for better decision making; new discoveries will help us achieve this hidden prospect.


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