When Ilber Manavbasi attempts a complicated piano riff, he rehearses more than the notes on the page.
“I practice under a variety of conditions and contexts. I practice when I’m hungry, tired, angry and happy. I practice different songs at different speeds and sometimes on different pianos,” said Manavbasi, a graduate student and researcher at the Beckman Institute for Advanced Science and Technology. “It’s the variety of practice that makes me a better performer.”
Variety may also make us better students, according to recent research by Manavbasi and colleagues at the University of Illinois at Urbana-Champaign.
Researchers found that varied practice, not repetition, prepared older adults to learn a new working memory task. Their findings, which appear in the journal Intelligencepropose diverse cognitive training as a promising whetstone for maintaining mental acuity as we age.
“People often think the best way to get better at something is to just practice it over and over again, but robust learning of a skill is actually supported by variation in practice,” said lead researcher Elizabeth A.L. Stine-Morrow, a Beckman researcher and professor emeritus of educational psychology at Illinois.
“While the importance of diversity in practice is well established in the area of motor learning, our study showed that this principle applies to the development of mental skills as well,” she said.
In their 1978 study, Kerr and Booth found that children who practiced throwing a bean bag at a target from a given distance were less likely to hit the target than children who had practiced throwing from different distances. On a larger scale, researchers have observed that preparation varies to produce a high level of performance in both sports and academics.
“World-class athletes who specialize in one sport are more likely to have had early experiences with multiple sports than their national-level counterparts, and Nobel laureates are more likely to have more early study and work experiences outside their discipline compared to nationally acclaimed award winners,” Stine-Morrow said.
He wondered how this concept could be translated into cognitive training. If learning were a sport, would a varied training regimen raise the level of play?
The researchers focused their attention on working memory, or the cognitive ability to keep one thing in mind while doing another.
“We chose working memory because it is a basic capacity needed to interact with reality and construct knowledge,” Stine-Morrow said. “It underlies language comprehension, reasoning, problem solving and many types of everyday cognition.”
Because working memory often declines with aging, Stine-Morrow and her colleagues recruited 90 Champaign-Urbana residents between the ages of 60 and 87.
At the beginning and end of the study, the researchers assessed the participants’ working memory by measuring each person’s reading ability — their ability to recall information while reading something unrelated. The researchers asked the participants to read and understand a series of logical and illogical sentences (for example, “The headdress worn by royalty is called a crown” or “An animal with orange and black stripes is a zebra”), each associated with a letter of the alphabet. Participants who remembered the letters in the correct order generally had stronger working memory, the researchers said.
Between reading span assessments, participants completed four weeks of cognitive training. During the first two weeks, participants trained on one of four practice regimens: the reading span task itself, a novel working memory task, multiple working memory tasks, and a control task unrelated to working memory. During the final two weeks, all participants practiced a variation of the reading span task.
Participants who practiced multiple working memory tasks showed the greatest improvement on the start-to-finish reading span assessment, outperforming those who had rehearsed the reading span task for all four weeks.
Although the mixed-practice group ultimately improved the most, researchers noted that it did not immediately outperform the others.
“They had to work for it,” Stine-Morrow said. “Mixed practice didn’t directly lead to better performance, but it led to better learning. That group was the slowest to improve on the reading span task, but eventually reached the highest peak.”
One reason varied practice can promote skill development is the principle of mutualism, or “mutual growth between closely related skills,” Stine-Morrow said.
These results provide early evidence for the concept of mutualism and hold promise for improving working memory later in life.
“With this study, we’ve demonstrated the general principle of mutualism through the lens of how it applies to working memory,” Stine-Morrow said. “If we extend this principle and combine it with different types of skills, we might be able to demonstrate broader effects.”
Due to limitations caused by the COVID-19 pandemic, participants used their home computers and iPads provided by the research team to complete all parts of the study remotely.
“We are grateful to the people in the Chambana community who supported our research, especially in this case, where they had to fit these activities into their lives over the course of four weeks. Most people found the activities challenging, but fun, and treated them like a game they wanted to win,” Stine-Morrow said.