In the world of college and professional sports, some coaches are notorious for having a short fuse, and for utilizing what some would consider a punitive (or abusive) style of coaching.
Legendary Indiana University basketball coach Bobby Knight comes to mind, whose controversial dismissal in 2000 was in response to allegations of abusive behavior (such as the 1997 choking incident ).
The recent movie Whiplash featured a similar figure (though fictitious, of course) – a teacher whom I’m guessing most of us would just as soon avoid if we could.
But for better or worse, some of these high-profile coaches (or teachers) seem to get results, which makes one wonder…
Which approach results in better learning? Is it possible that punishment could (…gulp) result in greater learning than a reward-based approach?
The “reaching” task
A team of researchers recruited 42 participants to compare the two approaches using a classic motor learning task that is often used in such studies.
Essentially, the task is to manipulate a cursor on a screen, by moving your hand in a quick “shooting” motion to get the cursor to pass through a target. Think Fruit Ninja , but played with a mouse (and with fruit that doesn’t move), and you get the general idea.
The challenge of course, is that after giving the participants an opportunity to get the hang of the setup, they alter the calibration so that the hand motion which used to make the cursor go up, now makes the cursor go 30 degrees to the right. Annoying at first, but something you can learn to adapt to with a bit of practice.
The rules of the game
Participants were divided up into three groups – one group was the “reward” group, another was the “punishment” group, and the last was the control group (which received points for each attempt just like the other groups, but totally at random and not at all associated with their performance).
The reward group started off with £0 (yep, this was a British study), and was told that they could win money by accruing more points. They would get 4 points for hitting the target, 3 for an error of <10°, 2 for an error of <20°, 1 for an error of <30°, and 0 for an error of >30°.
The punishment group, on the other hand, started off with £12, and was told that they would lose money depending on their score. There would be no points penalty if they hit the target, but would receive a -1 point penalty for errors <10°, -2 points for errors <20°, -3 points for errors <30°, and -4 points for errors >30°.
Reward vs. Punishment vs. Control – on adaptation
The participants all started out with ~100 practice trials, where they got acclimated to the task. Then, they had to do another ~100 trials without any visual feedback.
Then the fun began as the researchers rotated the calibration 30° counter-clockwise, and started doling out points for each hit or miss.
Quick! Before we proceed with the results, take a moment to think about this. Which group do you think learned fastest?
The researchers found that the negative points and loss of money led to faster rates of learning. And not because they were taking longer to plan out their moves or because they were being more cautious or careful – as there were no significant differences in movement times between groups.
The researchers also ran a test to see if it was the loss of money which accelerated learning, or simply the negative feedback. As it turns out, the negative feedback didn’t need to be connected to any loss of money. Even when the participants were told that accumulating negative points would not affect their payment, it still resulted in faster motor adaptation.
Reward vs. Punishment vs. Control – on retention
The researchers were not just curious about how quickly one might be able to improve performance in the moment (note that there’s a difference between adaptation during practice and long-term retention or learning – read this for a refresher), but also wondered how reward or punishment might affect the durability of their learning. As in, how long would they be able to retain what they had learned?
So, after the trials for points and money, the researchers tweaked the setup so that there was no visual feedback. So while the participants could still see the target, they received no visual feedback about their movements, and had no idea how accurate their movements were. This was to test the participants’ retention of what they had just practiced, to see how long it would take for their performance to degrade (sort of like, if you plugged up your ears so that you couldn’t hear sound anymore, how long would it take for you to play increasingly out of tune?).
Want to take a guess as to what happened in this set of trials?
Although the groups started off performing at the same level in the blind trials, the punishment group’s performance (as well as the control group) decayed significantly faster than the reward group’s performance, indicating that reward feedback seems to result in greater retention of motor skill learning.
Obviously, the takeaway here is not that extreme, severe, emotionally scarring levels of negative feedback are justifiable or worth adding to your toolbox of teaching strategies. After all, we all know how it has affected us not just emotionally, but in our ability to perform effectively, when feedback (whether intentionally or unintentionally) has led us to feel shame, guilt, or some sense that falling short of expectations makes us less of a person.
If anything, the study simply underscores the complexity of motor learning, and how there are different systems in play which affect different aspects of learning. And when it comes to coaching and teaching complex skills, I still find John Wooden or Pat Summit‘s instructive approach to be most appealing.
Nevertheless, the authors suggest that there may be times when thoughtful, measured, and appropriate “negative” feedback could be helpful in accelerating the rate of learning – after which rewards could be implemented to help reinforce or cement the desired behavior into place.
So…what do you think? Have you found any benign negative feedback strategies that have been helpful in your teaching, and in cultivating confident, courageous, and resilient artists?