A study in patients with epilepsy is helping researchers understand how the brain manages the task of learning a new language while retaining our mother tongue. The study, by neuroscientists at UC San Francisco, sheds light on the age-old question of why it’s so difficult to learn a second language as an adult.
The somewhat surprising results gave the team a window into how the brain navigates the tradeoff between neuroplasticity — the ability to grow new connections between neurons when learning new things — and stability, which allows us to maintain the integrated networks of things we’ve already learned. The findings appear in the Aug. 30 issue of Proceedings of the National Academy of Sciences.
“When learning a new language, our brains are somehow accommodating both of these forces as they’re competing against each other,” said Matt Leonard, PhD, assistant professor of neurological surgery and a member of the UCSF Weill Institute for Neurosciences.
By using electrodes on the surface of the brain to follow high-resolution neural signals, the team found that clusters of neurons scattered throughout the speech cortex appear to fine-tune themselves as a listener gains familiarity with foreign sounds.
“These are our first insights into what’s changing in the brain between first hearing the sounds of a foreign language and being able to recognize them,” said Leonard, who is a principal investigator on the study.
Read more: University of California San Francisco