Linking Genes, Brain Pathways to an Individual's Ability to Learn

Imagine you're a scholar planning to travel abroad to study. Or maybe you want to take a job overseas. You may know a smattering of the language spoken in the country you'll be living in, but you're by no means fluent.

What's the best (and fastest) way to learn a foreign language? Are there any shortcuts to ensure your success?

Ping Mamiya, a research scientist at the Institute for Learning & Brain Sciences, is doing a monumental study of biological mechanisms that underlie language learning. She hopes to reveal ways to help humans learn faster.

"We all learn differently," she said. Mamiya is zeroing in on brain and genetic indicators that pinpoint differences in how people learn, which could guide the design of programs and interventions that maximize learning.

Patricia Kuhl and Ping Mimaya at CNS 2015 meeting.

Photo caption: Patricia Kuhl and Ping Mimaya at the 2015 meeting of the Cognitive Neuroscience Society.

Mamiya's work was recognized this spring by the Cognitive Neuroscience Society, who bestowed on her one of its seven post-doctoral awards given this year for innovation. As part of the award, she gave a presentation at the society's annual meeting held March 28-31 in San Francisco.

"Learning a second language is one of the most challenging functions that the brain performs, especially after puberty," Mamiya said. "We're taking an integrative approach to studying language learning, by combining data from the brain and genes to understand behavior."

Read more about her findings in a blog post by the Cognitive Neuroscience Society.

Mamiya knows first-hand what it takes to become fluent in a second language. She grew up in Taipei, Taiwan and now uses a mix of English, Japanese and Taiwanese to speak with her family. In middle school she began learning English. Her English skills improved once she moved to the U.S. in 2006 to be a graduate student at Rutgers University, where she earned a doctorate in biopsychology and behavioral neuroscience in 2006.

But, she said that it wasn't until she was a mom raising her two children in the U.S. that Mamiya began feeling comfortable speaking English. Taking them to doctor's appointments, for example, with the pediatrician's rapid-fire questions felt like a more challenging language test than any other that she had taken in school.

Her research at I-LABS could make language learning easier.

Since summer 2013, Mamiya has been working in the lab of I-LABS co-director Patricia Kuhl. She started as a postdoctoral researcher and became a research scientist in January. Mamiya first became interested in Kuhl's research on how social interaction is essential for language learning in infants (pdf of research paper).

"If social interaction is critical for language learning, that suggests that executive function – the ability to pay attention to a teacher – is involved too," Mamiya said.

Executive function encompasses a range of higher-order cognitive functions, including planning, reasoning and attention. The prefrontal cortex is heavily involved in executive function. From her genetics training while at Rutgers, Mamiya knew that the COMT (Catechol O-methyltransferase) gene is heavily expressed in a fiber pathway in the prefrontal cortex.

So, if language learning requires executive function, which relies on fiber pathways in the prefrontal cortex, could it be that expression of the COMT gene in this pathway predicts a person's ability to acquire a new language?

Mamiya set out to find an answer, with colleagues at I-LABS and in UW's genome sciences department. Last August, the team collected brain scans and genetic samples from dozens of incoming Chinese students who were about to begin a 3.5-week intensive English immersion program as part of starting their undergraduate studies at the University of Washington. The students completed English language tests before and after the immersion program.

Ping Mamiya in genome sciences lab

Photo caption: Ping Mamiya at work in the laboratory of her collaborator Evan Eichler, a UW professor of genome sciences and an investigator at the Howard Hughes Medical Institute.

The research results represent a first step and are being written up for publication now. As Mamiya described at the Cognitive Neuroscience Society meeting, her findings suggest that students' success during the language immersion program was related to both the strength of the fiber tracks involved in executive function and which of the different variants of the COMT gene the individual possesses. This study was in young adults, and Mamiya plans to see if the similar brain and genetic mechanisms are at play earlier in development – during childhood. The research could reveal ways to expedite children's second language learning.

Mamiya says that the research is rewarding to her not just for the potential to improve language learning, but also as a way to more generally improve brain function. Learning a second language is just one (albeit, extremely complicated) task the brain performs, after all.

"This is why I switched from a medical to a basic research career," Mamiya said. "I want to help make more treatments available to patients with disorders related to brain function."