Enhancing the efficiency of learning: An interview with Hal Pashler

Hal Pashler is a full professor at the Psychology department of the University of California, San Diego. He received his Master degree at Brown University and a

Ph.D. degree at the University of Pennsylvania. His current research focuses on learning and memory and their enhancement.

Most of your career you worked on attention and dual-task performance, but in the past 6 or 8 years you seem to have focused most of your efforts on learning and memory questions that might have some practical applications. How did that shift occur?

I have always thought it was kind of embarrassing that after more than a century of effort, experimental psychology has had so little actual impact on the real world--and the lack of impact actually seems to be getting worse, as more psychologists focus on questions like neural localization which are incredibly remote from practical application. We've consumed quite a bit of money but haven't given much back to the world. For many years I had noticed that experimental psychologists had turned up lots of intriguing hints of potentially useful effects in the learning area-- but few people had taken the trouble to try to test out these ideas over meaningful time intervals and with tasks that have any practical utility. So these hints just sat buried in old papers, and never got turned into useful principles that could be applied in instructional and training technologies, and in advice for students and teachers. At some point I decided to see if I could help change this, and soon after that, some new funding streams emerged in the US which have helped me to ramp up my efforts in this area.

Do you consider what you are doing in the learning and memory area to be "applied research"?

I agree with the late Donald Stokes that rather than thinking of a continuum from "basic" to "applied", it's more sensible to think of research projects varying in two independent dimensions: generality of the questions and potential usefulness of the results. There is not necessarily any tradeoff between usefulness and generality. Of course, a lot of what people call "basic research" is high in generality but low in utility, and a lot of what people call "applied research" is high in utility but low in generality. My interest is in trying to identify and test principles of learning and memory that are highly general but also potentially very useful. I think these principles often have deep implications about underlying mechanisms, and I am trying to develop those in computational modeling which I am doing in collaboration with Mike Mozer from the University of Colorado computer science department.

One of your research goals is to enhance learning. How can learning generally be improved? Can people improve their learning ability themselves?

I think that it is possible to substantially enhance the efficiency of many kinds of learning and also to retard the degree of forgetting. But whether one can change a person's learning ability- in the sense of giving training that will transfer to completely novel situations- I am not so sure of that. Some investigators have recently been reporting that playing games and doing mental exercises can improve intelligence and learning ability, but I have been hearing of problems in replicating these results. I hope it is true though!

Do you apply your findings yourself when you want to learn something?

Not so much in my own life, but in my teaching I try to incentivize students to engage in appropriately spaced learning and review. In the future I hope to apply our findings in much greater depth.

What research methods do you use?

We do experimental research on a wide variety of learning tasks, from fact learning to perceptual category learning to learning of simple kinds of math skills.

What have you learned about the testing effect* that has most surprised you?

One thing we have found that has surprised me is that there seems to be very little cost to making people guess, even when the level of learning is low and the guesses that they produce are wrong. Intuitively I would have expected that producing wrong information would always leave a harmful trace in memory, but we aren't seeing that.

You have a very impressive list of publications. Which one would you like every ‘psychonoom’ or ‘psychonomist’ to read?”

I think our Psychological Science paper on the "ridgeline of optimal retention" is a short paper that people might find interesting.

http://laplab.ucsd.edu/articles/Cepeda%20et%20al%202008_psychsci.pdf

* The testing effect refers to the higher probability of recalling an item resulting from the act of retrieving the item from memory (testing) versus additional study trials of the item.