We're replicating a psychological experiment about perceptions of discomfort.

(participant exhales deeply) This is a bucket of cold water.

- Yep.

You're gonna put your hand in and you're gonna keep it in there for a duration that we won't tell you.

As it's in the water, you can rate your discomfort on this scale.

If basically you're at the point where, like, "I am in agony, let me take my hand outta here," you can dial it up to that.

- Oh my God.

- Yep, can't feel my fingers

- Stinging.

- A bit achey.

- Arctic.

- Painful.

- Numb.

- Numb.

- Numb.

- [Participant] More pain.

- [Participant] Pain maybe.

- Pain, can't hold it.

And obviously you've got two hands, we'll be doing this three times.

I'm replicating an experiment originally conducted by Daniel Kahneman and Barbara Fredrickson in 1993.

Just as in the original study, I've told participants we're investigating the difference in pain perception between dominant and non-dominant hands.

I'm assuming you're right-handed?

- Yeah, I'm right-handed.

- Okay.

But that is not the true purpose of the experiment.

- Left-hand in.

- Yeah, go ahead.

- Ooh, it's cold.

And we've started.

Yeah, all the way to the wrist.

That's good.

(participant exhales deeply) What's the physical sensation like?

- Cold, (laughs) freezing.

- Yeah, there's like a point where it almost feels like a muscle cramp.

- Both numbing and tingling.

- It is getting colder and colder, yes.

Half of the participants were randomly assigned to use their left hand first, the other half used their right hand first.

They indicated in real time how much discomfort they were experiencing.

- It's getting like progressively worse.

- It feels cold.

I wouldn't wanna stay there for very much very long.

- Good.

Are you from Russia or something?

- Yes.

- So you're used to the-

- I used to cold though.

(host laughs)

At the end of the trial, I told them to pull their hand out and give an overall rating for the experience.

- About a seven.

- Yeah.

- Yeah.

I mean, I wouldn't wanna swim in that.

- No.

- Three.

- Seven.

- Six.

Then they took a 15 minute break before returning to submerge their other hand.

(intense suspenseful music)

- Yeah, I can't hold it.

Bet that's real cold, huh?

- Yeah.

I could probably go another minute, I reckon.

What about an hour?

- No.

- It's like stinging this time.

- It started to feel like I can't feel my hand now.

Something like that.

(host laughs) Is that a good thing or a bad thing?

- It's a bad thing, of course.

(both laugh)

How did that feel?

- It felt a lot worse than my right hand.

(record scratching)

What participants didn't know is that the two trials were different.

They started out the same, one hand submerged in 14 degrees Celsius water for 60 seconds, and one of the trials ended there.

But the other trial lasted an additional 30 seconds.

During that time, the water temperature increased slightly to 15 degrees Celsius.

- Have I put it in here for longer than I did last time?

Feels like it's been a while.

This increase in temperature reduced discomfort.

- It seems to make the water slightly warmer.

It's slightly less uncomfortable.

But it was still uncomfortable.

This is not the sort of thing you'd wanna do for hours.

- No, I would like genuinely just be dead right now.

(host laughs)

Again, we randomized whether the long trial was first or second, and whether it was with the left hand or the right hand.

The ultimate question was, "If I were to ask you to repeat one of those two experiences, which would you choose?"

- Probably the left hand, yes.

- You'd do that first one again?

- Yeah, I think so.

- I would say the second one with the right hand.

- The first, the right hand.

- I'll go with the first.

- The first one?

- Yeah.

In our small-scale replication, seven out of 12 people said they would rather repeat the longer trial.

In the Kahneman and Fredrickson study, this preference was even stronger with almost 70% of their participants preferring the longer trial.

That is the same trial that they, in real time, indicated was painful for a longer time.

Both trials contained the same 60 seconds at 14 degrees Celsius.

The longer trial just added an additional 30 seconds with the water warming by just one degree.

This was still uncomfortable and it was 50% longer, and yet it's the trial most people preferred.

One of the participants in the original study after reporting that he would prefer to repeat the longer trial muttered, "The choice I made doesn't seem to make much sense."

So the first trial was 30 seconds longer?

- Yeah, okay.

You endured discomfort for longer.

But at the end, the discomfort reduced a little bit.

And the extra bit is not fun.

It's not like the extra bit was like, "Oh, this is great. I want to do this."

If I asked you which trial you'd want to do again,

- Probably the first one,

You'd tell me the first one.

- Yeah.

And that's the one that's actually a longer experience of discomfort.

- Yeah.

As hard as it is to understand, under certain circumstances, apparently, people prefer more pain to less.

But why is this?

Well, to investigate, Frederickson and Kahneman ran a follow-up study where they showed short and long versions of pleasant and unpleasant videos to undergraduate students.

Examples of pleasant videos included a puppy playing with a flower,

- [Audience] Aww.

And waves breaking on a beach.

While the unpleasant videos included the aftermath of Hiroshima,

And a medical film of an amputation.

- [Audience] Eww!

After the video, students were asked to rate their experience.

What they found was the length of the video had very little effect on the retrospective evaluation, positive or negative.

Kahneman and colleagues suggest this is due at least in part to the two different ways we experience the world.

In the moment as the experiencing self, or retrospectively thinking back on events as the remembering self.

If you're going through something unpleasant and someone offers you the chance to stop, you, the experiencing self, will likely take them up on the offer.

But for the remembering self, the duration of an experience seems to have much less importance.

(plane engine revving)

This is known as duration neglect.

A 2008 study found that the length of a vacation did not have any impact on how positively the vacation was remembered.

So if the duration of an experience doesn't affect your memory of it, what does?

(light music)

(group laughing)

The answer appears to be key moments, particularly ones that elicit the strongest emotional response.

As the novelist Milan Kundera wrote, "Memory doesn't make films, it makes photographs."

And those photographs usually capture the most intense, salient moments of the experience.

The most joyful,

(child laughing)

funny, painful, scary moments in life are the ones that are remembered, and therefore they come to represent the experience as a whole.

This is a version of the representativeness heuristic, A term coined by Daniel Kahneman and Amos Tversky in the 1970s.

They were studying how people think about probabilities.

Consider a family with six children.

Is it more likely that they were born in the order boy, boy, boy, girl, girl, girl, or girl, boy, boy, girl, boy, girl?

For the majority of participants, the first order was viewed as significantly less likely.

But in reality, both orders are equally likely,

but boy, boy, boy, girl, girl, girl feels less likely because it seems less random.

I mean, people have a mental model of randomness, and boy, boy, boy, girl, girl, girl does not fit this model.

We rely on representativeness all the time as a mental shortcut, but sometimes it can lead us astray.

One famous example developed by Kahneman and Tversky is known as The Linda Problem.

Linda is 31 years old, single, outspoken, and very bright.

She majored in philosophy.

As a student, she was deeply concerned with issues of discrimination and social justice,

and she also participated in anti-nuclear demonstrations.

So which is more probable?

Linda is a bank teller,

or Linda is a bank teller and is active in the feminist movement?

The majority of people who are asked this question give the second answer,

which makes sense because the description of Linda matches our mental model of a feminist.

But mathematically, it must be more likely that she's a bank teller,

because feminist bank teller is just a subset of bank teller.

All feminist bank tellers are, by definition, bank tellers.

Stephen Jay Gould said, "I know that the conjoint statement is least probable, yet a little homunculus in my head continues to jump up and down shouting at me, 'But she can't just be a bank teller. Read the description.'"

The thing about the representativeness heuristic, like many heuristics, is that we fall for it even if we are aware that we're falling for it.

I mean, technically, eggplants, cucumbers, and avocados are all berries,

but because they aren't small and sweet like strawberries or blueberries, we don't think of them as berries.

An eggplant does not match my preconceived idea of a berry.

So even though I know it's technically a berry, I'm gonna keep calling it a vegetable.

I mean, the salient feature of an eggplant is that I cook it like I would a vegetable.

Also, annoyingly enough, a strawberry is not technically a berry.

Botany is confusing.

So the representativeness heuristic is why we think that Linda is more likely to be a feminist bank teller rather than just a bank teller,

and why I can't bring myself to call an eggplant a berry.

And representativeness is how the peak moments in our past come to represent entire experiences.

But it's not the only thing that colors our perception of the past.

Our brains better recall and therefore assign a greater importance to more recent events.

This is known as recency bias.

So if you were to list all the meals you had in the last week, it would be easier to recall the most recent ones.

That's why how an experience ends plays an outsized role in how it's remembered.

I mean, how many people are rewatching "Game of Thrones" right now, for example, compared to, say, "Breaking Bad?"

I mean, the last season of "Game of Thrones" was so awful I don't think I'll ever watch any of it ever again.

The end tainted my view of the whole thing.

(wind whooshing)

And it seems like that also applies when judging the quality of a life.

In a 2001 study, researchers told a fictional story about Jen, a never-married woman without children.

She's extremely happy.

She has a job she enjoys, many close friends, goes on vacations and has many fulfilling hobbies.

Then she's hit by a car at the age of 30 and dies painlessly and instantly.

Taking her life as a whole, how desirable do you think Jen's life was?

For the other half of participants, researchers told the same story about Jen, but added another five years to her life.

Years that were pleasant, but maybe not quite as good as the first 30.

Then they asked the same question, "Taking her life as a whole, how desirable do you think Jen's life was?"

And what they found was that people judged Jen's longer life to be less desirable.

That living for those extra five good, but not great years actually reduced the overall perceived quality of her life.

The ending matters.

They repeated this same story with a Jen that lives to age 60 compared to age 65, and the results were the same.

Adding mildly pleasant years to a very positive life does not enhance it,

but actually decreases the perception of the quality of this life.

So when it comes to holding your hand in a bucket of cold water, your overall experience of the event boils down to two things,

Oh, yeah.

Like, I find that painful.

I can't believe people have been, like, standing in front of us acting so tough.

Both trials involved holding a hand in 14 degree water for the same duration.

So presumably they created the same peak of discomfort.

But the longer trial had a nicer ending.

Discomfort is backing off.

I mean, still uncomfortable, but, like, not quite as uncomfortable.

By adding a slightly less uncomfortable 30 seconds, Kahneman and Frederickson were able to trick participants into remembering the experience more fondly.

This is clearly a bad choice for the experiencing self, but a good choice for the remembering self.

This might seem like an insignificant party trick, but it actually has huge implications for our lives.

For example, if we remember a medical procedure like a visit to the dentist or a checkup more favorably, we're more likely to do it again, and that improves long-term health outcomes.

At the end of their 1993 paper, Kahneman and Frederickson ask, "Will a physician be allowed to add an interval of diminishing pain to the end of a medical procedure if the sole benefit of the added pain is to cause the patients to retain a more favorable memory of it?"

In 2003, Kahneman did exactly that.

Along with colleagues, he conducted a trial with 682 patients who underwent a colonoscopy.

Half of them went through a normal routine procedure, the other half had an extra three minutes at the end of the procedure where the tip of the colonoscope was left in, but not moved.

So it was uncomfortable, but less painful than the rest of the procedure.

The patients who experienced the extra three minutes of discomfort at the end rated the whole experience as about 10% less unpleasant.

They were also more likely to come back to do a follow-up screening procedure.

The peak-end rule also appears in design for customer experiences.

The cheap hot dogs at the exit of Ikea are an example.

The positive experience of a cheap, tasty hot dog or ice cream cone leads to a better memory of the whole shopping experience.

It's like a doctor giving a lollipop to a child after a checkup.

(gentle music)

Knowing that this is how the brain creates memories allows us to create better memories for ourselves.

If you wanna run more, don't do painful hill sprints at the end of your workout.

Instead, maybe do a pleasant cool-down walk while you talk to a friend or listen to your favorite music.

Wanna create better memories of your vacations?

Making it longer won't matter as much as creating exciting and novel days.

Make sure there's a high-peak experience, and also end it with something pleasant.

Are you quitting your job and want people to remember you fondly?

Well, make sure you are extra nice to your colleagues during your last few weeks.

In short, to create better memories, you should optimize for the peak and the end.

So the best way to close out a YouTube video is, I guess, with a wholesome message.

And why not footage of a cute dog playing with flowers?

(celestial music)

Our mindset plays a huge role in our perception of the environment.

And while this makes some experiences seem more enjoyable, it can also cause us to see things as worse than they really are.

But luckily, you can train your mind like a muscle to make meaningful improvements to your day-to-day life.

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I wanna thank Headspace for sponsoring this part of the video, and I wanna thank you for watching.