The brain is a totally impressive organ (and not a muscle!). It contains as many neurons as stars in our galaxy (85 to 100 billion), does not feel pain and can process complex information in just a few seconds. So much information completely phew on the brain which shows us, once again, how much this thing is badass. It is also and above all a thing full of mystery, which clearly controls our lives. Who dictates our choices. Besides, what happens up there when you have to make a decision?
1. “The halo effect” or how our social choices are guided
“The halo effect” corresponds to the first impression that someone makes on us, and determines in our brain, our reading of their qualities and faults. Some studies conducted in the business world show that, during job interviews, a recruiter is influenced by the first impression he has of the candidate. If he is seduced from the start, he will only retain the positive. Conversely, if he is skeptical from the start, he will mainly remember his faults, and his choice will quickly be oriented towards the first character.
2. Between 3 proposals, our brain will always go towards the one that makes a “consensus”
Take the example of a subscription to any magazine. Offer A costs you €10 per month, but commits you to 2 years. The B costs you double, but only commits you to one year. The C costs you €13 over 14 months. You’ll take the C, since it reduces dissonance, and has the advantages of the other two (reasonable price, and relatively short engagement). This responds to the “paradox of Buridan’s donkey”, an animal that would have died of thirst and hunger, between its bucket of water and food, not having been able to decide where to start. A third seal, containing a little of both, would have allowed him to make a choice.
3. “The anchor trap” guides our decisions
We have already told you that “the first impression is always the right one”. It’s wrong. But it’s what you think, and what makes it easier for you to cling to your first idea/impression to make a choice. This is the anchoring bias. It manifests itself in a particularly strong way with figures: it is fixed on a value and does not move from it. When you ask for a raise, your superior will anchor in his mind the first amount announced. After that, it will be very complicated to hope to obtain a little more.
4. …just like “availability bias”
Also called “availability heuristic”, it is the tendency to favor information directly available to our memory to make a choice. People are not looking for new information to shed new light on the issue, nor to find any objectivity: the choice is guided by their emotions, their memories and their recollections. These are reinforced by proximity to the source, to the detriment of more distant statistical data. For example, if you run into your old childhood friend again and he asks you to forward his resume to your employer, you’ll probably choose to do so without question.
5. Choosing a number from the infinity of existing numbers, what is the trick of the mentalists?
How do mentalists always find the number you’re thinking of when the choice is endless? Well, like in a magic trick, there is trick! Your brain does not really “choose”: the mentalist makes you do a series of calculations which, in the end, leads to a single and unique result: the number 9, and this, regardless of your starting number. You feel like you’ve made a choice, but in the end… Not really.
I show you: choose a number strictly at random (239, for my part). Multiply it by 10 (2390). Using your calculator, subtract this number from the starting number (2390-239 = 2151). Finally, add all the numbers together, and you will get a 9! (2+1+5+1 = 9).
6. Statistically, a person who is asked to choose a number between 1 and 10 will more often choose 7
More often than not, people choose the “7”. Everyone has their own explanation of why. For a time, it was thought that this could be explained by the fact that the “7” has no particular mathematical property, but in 2006 Jean-Paul Delahaye, mathematician and professor at the Fundamental Computer Science Laboratory of Lille (University of Lille), explained that this was “only valid in Europe or the United States. Other countries “prefer” the 2, the 3… So it’s a cultural bias”. For some, the reason is simple: 7 is sacred in several religions, often considered a lucky number. Others think it’s because the “7” is the highest odd prime number on the list. In English, it is sometimes considered that the choice is on him because “seven” is the only number with two syllables… Yes, the hypotheses of explanations are going well! Still, it is often this number that outweighs its 9 other comrades.
7. In reality, our brain makes a decision about 10 seconds before we realize it.
According a study conducted by researchers at the University of New South Wales in 2019, when we make a choice, our brain had already done so several seconds before us, without our being aware of it. Already in 2008, works had shown that it was possible to predict motor decisions in advance, by noting activity in the pre-frontal and parietal cortex a few seconds before the guinea pigs became aware of their decisions.