Interesting study on cognitive biases from Daniel Kahneman’s Thinking, Fast and Slow …
Patients undergoing a painful medical procedure – think, colonoscopy without anesthesia – recorded their pain levels during the procedure on a range from no pain (zero) to excruciating (10).
Some of the procedures were short in duration … others were longer.
Below is the pain chart for 2 representative patients.
The patients were asked – after the fact—how painful the procedure was.
What’s your bet? Which patient claimed to have undergone the more painful procedure?
Obvious answer is B, right?
B’s pain got as bad as A’s during the early part of the procedure … and B’s procedure lasted a lot longer.
A claimed the more painful procedure.
How can that be?
Kahneman chalks it up to 2 cognitive biases: the peak-end rule and duration neglect.
Let’s take peak-end first …
Researchers concluded that patients rated their overall procedure pain as a function of the peak level of pain endured and the level of pain at the end of the procedure.
So, while A & B reached the same level of peak pain … A’s peak was closer to the end of the procedure – and very memorable. Apparently B – whose procedure lasted longer — had time for the memory of the peak pain to fade.
B didn’t hold it against the procedure that it lasted a comparatively long time. That’s duration neglect.
The biases have relevance beyond medical procedures.
Imagine that you go to a concert.
The artist gives you a couple of hours of great musical entertainment,
But, during the encore, he goes off an expletive-filled tirade against a cause that you support.
How enjoyable was the concert?
Most people would walk out with a sour taste in their mouth … not humming one of the artist’s songs.
That’s duration neglect (diminishing the hours of strong performance) and peak-end rule (the unpleasant tirade during the finale).
Bottom line: appreciate the good times … and be happy if the pain ends early.