Imagine you’re going to have a painful medical procedure. You could choose to have it last 6 minutes or 12 minutes. Which option do you take?
Six minutes, of course. Right? Well, it’s not so simple. Take a look at these charts from Daniel Kahneman’s remarkable book Thinking, Fast and Slow.
The procedure – a colonoscopy (ouch) – had identical intensities of self-reported pain, but it lasted 3 times as long for patient B than it did for patient A. Clearly, patient B will remember this as being a more unpleasant experience than will patient A.
Now here’s the interesting bit.
When asked to report on the “total amount of pain” they had experienced during the procedure, patient A “retained a much worse memory of the episode.” WHAT? Why?
There are two main reasons. One is called the ‘peak-end’ rule. The overall memory (pain in this case) can be predicted by taking an average of the most intense moment of an experience and at its end. The most intense pain for both patients was 8, but the end rating for patient A was 7, while for B it was only 1. Thus the peak-end average for A was 7.5, and only 4.5 for patient B. The procedure ended for patient A at a really painful moment, and so he remembers it as being far more unpleasant than does patient B, even though patient B’s procedure lasted 3 times as long.
How can the remembering self ignore the length of an experience, either pleasant or unpleasant? It’s called ‘duration neglect’.
In this case, “the duration of the procedure had no effect whatsoever on the ratings of total pain.” It would seem that to our memory of events, how long they lasted has little impact on how we value them.
Take this example. Participants in an experiment were asked to immerse a hand in painfully cold water for 60 seconds. They were then asked to immerse their other hand for 90 seconds. The first 60 seconds of the experience were identical to the first, but at the one-minute mark the experimenter silently opened a valve that allowed slightly warmer water to flow into the tub. For that additional 30 seconds, the participants experienced a slight decrease in the intensity of pain.
Participants were then told that they would endure a third trial, but they could choose either the 60-second or the 90-second immersion. “The peak-end rule predicts a worse memory for the short than for the long trial, and duration neglect predicts that the difference between 90 seconds and 60 seconds of pain will be ignored.” Indeed, a whopping 80% of participants chose to repeat the 90-second immersion.
Had they been asked at the start, “Would you prefer the longer or the shorter immersion?” certainly the vast majority would have chosen the shorter. But they were not asked that, and they chose to repeat the experience that, while objectively worse, held a less aversive memory.
Meet Jen. Jen lived a very happy life, “enjoying her work, taking vacations, spending time with her friends and on her hobbies.” She was killed instantly and painlessly in a car accident at the age of 30. How desirable do you feel Jen’s life was? How much total happiness do you feel that she experienced?
Here’s another story. Jen’s life was exactly the same as above, but she was killed at the age of 35. For the last five years of her life, she was slightly less happy than she had been before. Rate her overall happiness.
Now imagine Jen lived to be 60 before she was killed, living a very happy life the entire time. How desirable was her life? Go ahead, think about it, I’ll give you a moment.
When these scenarios were run by participants in experiments, the results were surprising. Adding 5 extra years to Jen’s life that were slightly less happy dropped the evaluation of the overall happiness of her life considerably. In other words, 5 additional years that were not quite as good as the previous 30 made the rating of those previous 30 years plummet. A clear example of the peak-end rule.
Moreover, doubling Jen’s life span had no effect on the overall rating of her entire life. There was no cumulative effect on the rating of total happiness: 60 years of happiness is no better than 30 years of it. Duration neglect is afoot here. “In intuitive evaluation of entire lives as well as brief episodes, peaks and ends matter but duration does not.”
We experience these effects every day, mostly unconsciously. How many times have you read a book or watched a movie that you enjoyed for pretty much its entirety, but were deeply disappointed by the ending? You tend to remember it, even if it was 98% excellent, as being mediocre at best. Endings matter. A lot.
My brother and I have often remarked on how our evaluation of a day of fishing is affected by when the fish were caught. Say we catch 20 fish each in the course of a 6-hour excursion. If most of them come at the beginning, and we have a long dry spell toward the end, we’ll end up feeling that it was a pretty weak day of fishing. If instead we finish with a flurry of action, we’ll tend to remember it as a fantastic day of fishing. It doesn’t matter that the number of fish was the same, all that matters to our perceived memory of the day was the peak of action and when it ended.
We can use this information in many situations with our kids, from choosing between ripping off a Band-Aid (plaster) quickly but painfully and slowly easing it off, to how to make a long car trip a more pleasant memory.
Take the car trip. Say you’ve got a 6-hour drive ahead of you. If you’re like me, you want to get as much road behind you as possible, stop maybe for lunch roughly half-way through, then push on the rest of the way without stopping because it’s better to just get there.
But from what we know, that approach is all wrong. If instead we take, say, two 30-minute breaks toward the end at fun spots along the road, it may add an hour to the overall trip but the memory of the trip will be far better, given the peak-end rule and duration neglect. And next time you set off on a long trip maybe your kids won’t moan so much.
There seem to me to be a huge number of applications for this simple knowledge to make activities with your kids more pleasantly memorable and the unpleasant necessities less disagreeable. Do you have any ideas, any examples where you could put this to use? We’d love to have you share.