We use our mind every second of every day, but it's safe to say no one understands exactly how it functions. Even psychologists and neuroscientists are often stumped by why we think and behave the way we do.

Some of those researchers have appeared on the TED stage to talk about the questions that keep them up at night. The following 11 talks - on topics like decision-making, happiness, and our concept of time - are some of the most thought-provoking in TED's collection.

Each one will bring you one step closer to understanding who you are, and who you might be.

1. Tali Sharot: Your inherent bias toward optimism is a double-edged sword.

Sharot is a neuroscientist who, along with her colleagues, was able to reduce people's optimism by controlling activity in certain areas of their brains. 

On the one hand, this could be a positive development. After all, Sharot says in her talk that people underestimate the likelihood of bad things like cancer happening to them, so they're less likely to take precautions like scheduling medical checkups.

But on the other hand, Sharot says that optimism enhances our well-being because it acts as a self-fulfilling prophecy. When we believe we're going to land that job or promotion, we're more likely to get it.

So how do you reconcile those two viewpoints? "We would like to protect ourselves from the dangers of optimism, but at the same time remain hopeful," Sharot says. "The key here really is knowledge."

She illustrates this idea with a cartoon of penguins trying to fly off a cliff. The ones that are successful have a back-up plan:

"If you're an optimistic penguin who believes they can fly, but then adjusts a parachute to your back just in case things don't work out exactly as you had planned, you will soar like an eagle, even if you're just a penguin," she concludes.

2. Dan Ariely: You have less control over your own decisions than you think.

Most of us believe we're totally in control of our own decisions. But as Ariely, a behavioural economistexplains in his talk, we're incredibly susceptible to outside influences.

One of his most enlightening examples is based on an old Economist advertisement for three subscription levels: $59 for online only, $159 for print only, and $159 for online and print.

Ariely figured out that the option to pay $159 for print only exists so that it makes the option to pay $159 for online and print look more enticing than it would if it was just paired with the $59 option. 

Using examples from medicine and online dating, Ariely proves that traditional economics can't fully explain irrational human behaviour - and that's where behavioural economics comes in.

"When it comes to the mental world … we somehow forget that we are limited," he says. 

"I think that if we understood our cognitive limitations in the same way we understand our physical limitations … we could design a better world."

3. Sheena Iyengar: The freedom to choose is not always empowering.

Iyengar's talk illuminates how our beliefs about choice are shaped by our cultural backgrounds. For example, Americans tend to believe that if a choice affects them, then they should be the one to make it.

Compare that to people from Asian backgrounds, who generally believe that it's best to defer to other people you trust and respect.

"It is a mistake to assume that everyone thrives under the pressure of choosing alone," she says.

Iyengar, a psycho-economist, debunks the idea that the more choices you have, the better decisions you make. In fact, she says, when you give people 10 or more options, they tend to make poorer decisions in areas like healthcare and investing. 

Ultimately, Iyengar says it's about accepting that constraint can in some contexts be more liberating than freedom.

The American narrative promises "freedom, happiness, success. It lays the world at your feet and says, 'you can have anything, everything'", she explains.

Yet upon closer examination, Iyengar says you'll realise that the idea of choice is much more complicated and can be interpreted in many other ways.

4. Daniel Kahneman: Your happiness depends heavily on your memory.

According to Kahneman, a behavioural economist, every individual is divided into an experiencing self and a remembering self. The differences between these two selves are critical to our understanding of human happiness. 

To illustrate this idea, Kahneman refers to an experiment in which two groups of patients underwent a colonoscopy.

The group that experienced the peak of their pain at the end said they suffered more - even when their procedure was shorter. Kahneman says that the second group's experiencing selves suffered less, but their remembering selves suffered more.

The remembering self, Kahneman says, is the one that makes decisions, like which colonoscopy surgeon to choose the next time around.

"We actually don't choose between experiences, we choose between memories of experiences." Even when we contemplate the future, Kahneman says, "we think of our future as anticipated memories."

Bottom line: What makes you happy in the immediate present won't necessarily make you happy when you reflect on your life overall - and it's important to consider that idea the next time you're making a big decision.

5. Dan Gilbert: You have no idea what will make you happy in 10 years.

Ask people how much they'd pay to see their favourite musical artist play a concert in 10 years, and they'll say about $129. Ask them how much they'd pay to see their favourite artist from 10 years ago play today, and they'll say about $80.

For Gilbert, a Harvard psychologist, this disparity reflects our fundamental misunderstanding of how much our values and personalities change over the course of time. 

In his talk, Gilbert explains that we constantly think we're done growing - we think our favourite artist today will still be our favourite in 10 years. But in reality, we're never quite finished, and there's a good chance we won't love that artist the same way in a decade.

He calls this phenomenon "the end of history illusion".

"Human beings are works in progress that mistakenly think they're finished," he says. 

This is ultimately why, Gilbert says, we so often make decisions we regret. Understanding this cognitive limitation is one way to make wiser choices going forward.

6. Carol Dweck: There's power in believing you can achieve.

Dweck is a psychologist best known for her hypothesis of fixed versus growth mindsets. People with a fixed mindset believe achievement is based on innate talent alone, while those with growth mindsets believe their abilities can be developed through hard work.

Ultimately, Dweck says in her talk, people who exhibit growth mindsets are more successful.

This hypothesis has important implications for the way we raise kids.

For example, instead of telling kids how smart they are, we can instead focus on their attitude. Dweck mentions a study in which some kids were explicitly told that when they learn something new, their brain gets stronger.

As it turns out, those kids performed better academically than kids who weren't taught this growth mindset.

"We can praise wisely, not praising intelligence or talent. That has failed," she says.

"But praising the process that kids engage in - their effort, their strategies, their focus, their perseverance, their improvement - this process creates kids who are hardy and resilient."


7. Peter Doolittle: You can remember more of what you experience.

Doolittle's talk highlights the relative limitations of our working memory, or the part of your consciousness that you're aware of at any given moment.

According to Doolittle, a professor of educational psychology, we can remember about four different things for about 10 to 20 seconds unless we do something with that data, like talk to another person about it. Otherwise, that information disappears.

Fortunately, Doolittle offers several strategies for enhancing your working memory and preventing those cognitive slip-ups most of us are all too familiar with. One strategy is to conceptualise things in images.

"We are built for images," Doolittle says. "We need to take advantage of that."

Another technique is to ask questions, even to yourself, that help you process incoming information. Do you agree with the person speaking? How can you apply the ideas in your own life? 

Ultimately, Doolittle says, "what we process, we learn. If we're not processing life, we're not living it. Live life".

8. Philip Zimbardo: Your perspective of time is a major factor in your happiness.

Zimbardo, a psychologist perhaps best known for conducting the Stanford prison experiment, is also fascinated by people's time perspective, or how we divide our experience into different temporal categories.

In his talk, Zimbardo says that people differ in how much they value past, present, and future experiences. You can break it down even further: In each group, some people focus on the positive and some people focus on the negative. 

He suggests that our unconscious bias toward a particular time zone and toward positive or negative information influences every decision we make.

If you're overly focused on the future, for example, you may sacrifice time with family while you're striving for success.

 The optimal time perspective for decision-making is high on past-positive, while only moderately high on future experiences and positive present experiences.

Zimbardo uses himself as an example: "I'm here as a future-oriented person who went over the top … I've added present-hedonism, I've added a focus on the past-positive so, at 76 years old, I am more energetic than ever, more productive, and I'm happier than I ever have been."

9. Ben Ambridge: Most of what you know about the human mind is wrong.

Ambridge, a psychologist, devotes his talk to deconstructing some of the most common misconceptions about human psychology.

Here are some examples of the myths:

  • Rorschach inkblot tests can assess your personality. (They're not used by modern psychologists.)
  • Some people are visual learners; others are auditory learners. (The best instruction method depends on what you're trying to learn.)
  • We only use 10 percent of our brain capacity. (Nearly everything you do involves the whole brain.)

Perhaps the greatest myth Ambridge wants to dispel is that "psychology is just a collection of interesting theories, all of which say something useful". 

"The only way we can make progress is to test these predictions against the data in tightly controlled experimental studies. And it's only by doing so that we can hope to discover which of these theories are well supported," he says.


10. Tim Harford: Don't resist discomfort - it could make you more productive.

Harford is a columnist at The Financial Times and the author of the 2016 book Messy, in which he argues that a little bit of disarray can make you more creative.

In his 2015 talk, Harford makes a similarly counterintuitive point: Some frustration, or awkwardness, or other obstacles on the path to success can ultimately enhance your productivity.

Here's one example Harford cites to support his point: For a 2006 study, researchers had groups of students try to figure out a murder mystery.

Some of the groups included four friends; some of the groups included three friends and a stranger. Sure enough, groups with the stranger were more likely to solve the mystery correctly.

Interestingly, however, groups of friends were more confident that they'd solved the mystery correctly than the groups with one stranger.

"I think we need to gain a bit more appreciation for the unexpected advantages of having to cope with a little mess," Harford tells the audience.

If we lean into difficulty and challenge instead of resisting it, we might find that the results of our efforts are even more remarkable than they would otherwise be. 

11. Brian Little: There's no such thing as a completely stable personality.

According to cognitive psychologist Brian Little, everyone has three natures.

There's your 'biogenic"'nature, or your neurophysiology. There's your 'sociogenic' nature, which is informed by sociocultural factors. And perhaps most interestingly, there's what Little calls your 'idiogenic' nature: what makes you you.

Little's talk focuses on this idiogenic nature, and on the fact that labelling someone an introvert or an extrovert isn't quite sufficient. What makes every person different, he says in his talk, is their personal projects.

When we're working on these personal projects - one example he gives is trying to get proper care for a parent who's in the hospital - our 'free traits' emerge.

So even if you're ordinarily agreeable, you might act disagreeable when dealing with the tiresome hospital administration.

Little says: "Don't ask people what type you are; ask them, 'What are your core projects in your life?'"

Little's core project is being a professor. Even though he technically identifies as an introvert, he says he acts in a typically extroverted way at 8 am to keep his students engaged.

Then, of course, knowing that he's more introverted, he goes somewhere on his own to recharge - even if that's the men's room.

This article was originally published by Business Insider.

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