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We fear uncertainty


This is a simple chapter and I don't think many of us really need too much convincing. 


From an evolutionary standpoint, uncertainty had a high potential for danger. If you are certain how something will turn out,  you'd probably encountered it before (and you have lived to tell the tale). If you are certain how something will turn out, you can prepare for it. Now imagine your ancestor entering a dark valley they have never visited before - would there be predators? Would there be difficult terrain? When we don't know what's going to happen,  our bodies and minds react instinctively to protect us. Fear is triggered to deter us from going further into uncertainty and to turn around and stick to what we know. 


This is still evident today. Are we more frightened when we walk through a quiet lane in the dark or in the day? Think about horror movies or haunted houses - it often happens in a dark environment, where there is more uncertainty. Also, remember the first time you did anything - your first day at school, your first speech in public, your first date, what did you feel? Now compare to how you feel after doing something for the 100th time. 


Neuroscientist Beau Lotto elaborates more on how the brain reacts to uncertainty below:

"How do you get seasick? You get seasick because your rain cannot reconcile the uncertainty of conflicting signals. When you go down below in a boat and your eyes are moving and registering the boat, and your eyes are saying, “Oh, we’re standing still,” but your inner ears are saying, "No, no, we’re moving.” And your brain cannot deal with that conflict so it gets ill. 

While getting a little seasick is not the end of the world the consequences of too much uncertainty can be tremendous. Too much uncertainty increases brain cell death. It decreases plasticity in the brain and transforms you into a more extreme version of yourself."

One last thing on uncertainty. When things ahead are uncertain, your brain becomes uncomfortable and fearful. It then starts to generate terrible outcomes that can potentially happen. The greater the lack of clarity in what would happen next, the worse these thoughts get.


This is what psychologists call "awfulising" - a dramatic and irrational thought process, where we overestimate the negative consequences of events and perceived threats.  In the process of awfulising, you start feeling more fear and greater inertia to stay in certainty. And this is a major reason change is very difficult.


This quote, commonly attributed to Mark Twain, is quite apt: "I am an old man and have known a great many troubles, but most of them never happened.”

So how can we manage our fear of uncertainty? On one hand, this fear could be well-founded: uncertainty could lead to a bad outcome for us; on the other, there are so many things to try out in life and if we always try to keep it safe, we would hardly live at all. 

The 2 articles below provide answers:

1) How can we manage our fears?

2) How Isaac Lidksy dealt with going blind


Pregnancy kit

Ethan Bromberg-Martin and Okihide Hikosaka showed that monkeys, too, prefer to be in the know.5 The hairy animals were not applying to Harvard Business School, of course; nor were they curious to receive information regarding their reproductive system. What was occupying the monkeys’ minds was whether they were about to receive 0.88 milliliters of water (a big reward) or just 0.04 milliliters of water (a small reward).

This is how the experiment worked: on each trial, the monkey would receive either a big water reward or a small water reward. By moving its eyes to one of two symbols on a screen (let’s say a blue star or pink square) seconds before the water was delivered, the monkey could indicate if it desired advance 

information. The monkeys were trained for weeks to make sure they understood what every symbol meant. If the monkey selected to receive this advance information, a third symbol appeared on the screen (for example, a red circle), indicating whether the monkey was about to get lots of water or just a little. Finally, the water was delivered straight into the monkey’s dry mouth.

When all the data had been gathered, Bromberg-Martin and Hikosaka were amazed to find that not only did monkeys want advance information, they were also willing to “pay” for it. The monkeys were willing to give up a few drops of precious water in order to know ahead of time if they were about to get a large reward or just a small one. Time and time again, the monkeys would move their eyes to indicate that they wanted to know.

When neurons “fire,” they generate a signal, which flows down the neuron as a current, in and out of the cell. The micro-electrode can pick up on these changes in voltage. What Bromberg-Martin observed was that the monkey’s brain was treating information as if it was a reward in and of itself. These neurons, known as “dopaminergic neurons,” were firing in response to information as they would in response to water or food.

Dopaminergic neurons are cells in the brain that release the neurotransmitter dopamine. These neurons send signals from the midbrain, an evolutionarily “old” part of the brain, to many other regions of the brain, including the striatum, a part of the brain that processes rewards, as well as areas in the front of the brain that are important for planning. Dopamine is released when we expect a reward and when we receive an unexpected reward. Well, it turns out that dopamine is also released when we expect information and when we unexpectedly receive information. In the brain, the “currency” for tangible goodies, like sex and plum pie, looked a lot like the “currency” for pure knowledge. In fact, Bromberg-Martin was stunned to see that the neurons were firing at a similar rate to the expectancy of information as they would to the delivery of 0.17 milliliters of water. In other words, the neurons were as excited by advance knowledge as they were by drops of H2O, which are necessary for our existence.

In one experiment, Filip Gesiarz and I invited people to play a lottery game. Every time they played the game, they were presented with two digital doors—a blue door and a red door. Behind each door awaited a cash prize; some prizes were relatively big, and some were small. The red door was always better than the blue door—behind the shiny red door lay more cash than behind the blue door. A computer program would select one of the doors for the participant at random, and they would be given whatever was behind it. Before the computer made the choice, we allowed people to have a sneak peek behind one door. Would they like to see what was hidden behind the red (large prize) door or the blue (small prize) door? Their decision would have no effect on the outcome. Time and time again, people preferred to open the red door over the blue door. They wanted to know what the best-case scenario was, not the worst.

Caroline Charpentier and I teamed up with Ethan Bromberg-Martin. This time,

instead of recording the activity of neurons in a monkey’s brain, we recorded activity in the human brain using a brain-imaging scanner.

Imagine you are a participant in our experiment. You meet Caroline, the French experimenter, who explains that you will be lying in a long tube-shaped brain-imaging scanner while playing a lottery game. The game will be divided into two parts. Half of the game will be all about winning. Each time you play the lottery, you will either win one dollar or get nothing. Pretty good, you think. The other half of the game is all about losing. Each time you play the lottery, you will either lose one dollar or lose nothing. Not great, I know, but you have no choice; if you want to participate in the experiment, you must play the game. Oh, and every time you play the lottery, Caroline will ask you if you want to know the outcome of that round of the game or remain ignorant. At the end of the experiment, we will pay you the total of what you earned throughout, regardless of which outcomes you selected to reveal and which to remain ignorant of. Think about it as if you are sitting in front of a slot machine: you close your eyes and pull the lever; the reels spin round and round and eventually stop. Do you open your eyes? Do you want to know?

Just like Kate and Bromberg-Martin’s monkeys, people wanted to know. But they wanted to know more about potential wins

than potential losses. In other words, people were more likely to open their eyes if they were playing the win-or-nothing slot machine than the lose-or-nothing slot machine. What’s more, the better the odds of winning with the slot machine, the more people wanted to know the outcome. We displayed the probability of winning each time people played our little lottery—the more likely people were to win, the more they wanted to know, and the more likely they were to lose, the less they wanted to know. In other words, people want to tear open envelopes that promise good news and toss away ones that promise bad news.

What about the brain? Remember those neurons Bromberg-Martin discovered firing in the monkeys’ brains in response to advance information about water? We found evidence that suggested that neurons in the same region in the human brain also increase activation in anticipation of information about financial gains. However, in anticipation of information about losses activation was decreased. In addition, whenever our participants knew information was coming—regardless of whether it was information about losses or wins—another region in the brain, the orbital frontal cortex, was activated. It seems that in our brains there are two types of responses to information; one type of neurons values knowledge per se, and the other type values knowledge that is likely to make us feel good.

An even more striking example comes from a study of 396 women 

who gave a blood sample and were later told that those samples had been analyzed to identify genes that predispose a woman to breast cancer.9 Would they like to receive the results of the test? The women simply had to say yes, with no effort required. Yet 169 chose not to know. This is quite staggering! Unlike people at risk of developing Huntington’s disease, individuals at risk of suffering from breast cancer can take precautionary actions to reduce the likelihood of their developing the disease. Nevertheless, 42 percent of the individuals tested decided not to receive information that could possibly save their lives.

This may seem surprising, but think about it like this: while the benefit of knowing would be to reduce the uncomfortable feeling of uncertainty, the cost of knowledge would be not having the option to believe what you would like to believe. As long as we are ignorant of the test results, we can continue believing that we are healthy; we can fill our minds with positive thoughts. Taking the test puts those thoughts in danger, because once we receive the test results, we cannot unlearn them. Once you know that you carry an ill-fated gene, that knowledge will be engraved in your brain forever. If the diagnosis is undesirable, your life will change instantly. So not knowing can, perhaps, keep us happier at

Was this a pleasant experience? Oftentimes when we are making extreme changes to our lives such as changing careers, moving to a new place, trying something potentially dangerous for the first time we see a drop in our health and mental state. This is because our brains are deeply wired to avoid this type of uncertainty at every turn. 

Every minute of every day we are making hundreds of assumptions, which helps us mentally avoid uncertainty. As I type this I assume the chair I am sitting on will not give way and leave me sprawled out on the floor. I assume the desk in front of me was assembled correctly, I assume the keyboard on which I am typing will continue to work, and so on and so forth. 

These assumptions are absolutely critical to our survival. Can you imagine what a nervous wreck we’d be if I stopped to make sure my chair was sturdy each minute. First of all I’d never finish writing this article but even worse I would most likely worry myself into no longer using this chair, checking the screws on my desk, and monitoring the battery life of my keyboard. 

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