The results I described in the previous post surprised me because (a) my performance suddenly got better after being stable for many tests and (b) after the improvement, further practice appeared to make my performance worse. I’d never before seen either result in a motor learning situation. If you can think of an explanation of the result that practice makes performance worse, and animal learning isn’t your research area, please let me know.
Learning researchers used to think of associative learning as a kind of stamping-in process. The more you experience A and B together, the stronger the association between them. Simple as that. In the 1960s, however, several results called this idea into question. Situations that should have caused learning did not. The feature that united the various results was that in each case, learning didn’t happen when the animal already expected the second event. If A and B occur together, and you already expect B, there is no learning. Theories that explained these findings — the Rescorla-Wagner model is the best known, but the Pearce-Hall model is the one that appears to be correct — took the discrepancy between expected and observed — an event’s “surprise factor” — rather than simply the event itself, to be what causes learning. We are constantly trying to predict the future; only when we fail do we learn.
In my motor-learning task, imagine that the brain “expects” a certain accuracy. When actual accuracy is less, performance improves. Performance stops improving when actual accuracy equals expected accuracy. The effect of more omega-3 in the blood, and therefore the brain, was to increase expected accuracy. (One of the main things the brain does is learn. If we do something that improves brain performance in other ways, it is plausible that it will also improve learning ability.) Thus the sudden improvement. The decrement in accuracy with further practice came about because, when the omega-3 concentration went down, actual accuracy was better than expected accuracy. Accuracy was “over-predicted,” a learning theorist might say. So the observed change in performance was in the opposite-from-usual direction. Accuracy got worse, not better.
Related happiness research. “Christensen’s study was called “Why Danes Are Smug,” and essentially his answer was it’s because they’re so glum and get happy when things turn out not quite as badly as they expected.”
“If you can think of an explanation of the result that practice makes performance worse, and animal learning isn’t your research area, please let me know.”
Wild guess: Repetition makes the task more boring, which reduces concentration.
Thanks, LemmusLemmus. The repetition rate wasn’t unusual when accuracy started getting worse.
Seth,
yes, but even with a constant repetition rate, couldn’t the task get more boring?
If I see film XYZ once a week, it’s going to get more boring (on average) every time I see it.
To add to my first post, it may reduce not only concentration, but also motivation.
To add to my second post, I think there may be threshold effects.
Both is nothing more than personal experience, but to illustrate, a few years ago, I got into playing a popular computer game (basically, a move-cursor-and-shoot game). Once I was pretty good at it, I lost interest.
The same happened with a pinball machine earlier. I broke the record on one and then couldn’t be bothered anymore both about that particular machine and others of the same type.
I’m sure the accuracy reduction over time wasn’t due to boredom. It started just after I’d observed one of the most fascinating-to-me results in all my self-experimentation.
Performance gets better after period of stability. Isn’t that a standard feature of learning, as the learnt stuff gets shuffled into neurons in a more permanent part of the brain (e.g., research on stroke victims who thought they reached limits of improvement possible with therapy, but found more improvements when therapy was kept up for longer periods).
Further practice makes performance worse. Well, Tim Gallwey (Inner Tennis) kinda built a career on that, didn’t he? Once you’ve learned the basic task, focus from the wrong part of the brain can interfere with performance, eh?
Also, if you haven’t already, you probably really need to control for aspirin use with these tests, due to aspirin’s ability to combine with docosanoids to form potent, inflammation-terminating resolvins and protectins.
But I just learn this stuff from Oprah, so it might be wrong.