We all know that you can't teach an old dog new tricks. But what about a new language? Previous research suggests that it is forsmall childrenis much easier to learn a new language than for their parents or even older siblings. A new study now offers a solution to make language learning easier for adults.
Using a light,imperceptible brain stimulationThrough the ear, scientists discovered improvements in adults' ability to recognize sounds in a foreign language.
In the study, published in the journal Science of Learning, the authors explain that part of what has made language learning difficult as we get older is that the adult brain no longer has the same plasticity - or that Ability to remodel its synaptic networks to accommodate new information, as it once did in childhood. But the brain hack discovered by the scientists could help adults overcome their own brain limitations.
This small stimulation device can help adults learn new languages better
To test this for language learning, the team developed a small external ear device to stimulate a participant's transcutaneous vagus nerve (tVNS) with painless electrical pulses.
Mandarin (Standard Chinese) is considered one of the most difficult languages to learn for native English speakers, in part because the language - like many others around the world - uses distinctive pitch changes to change the meaning of words that otherwise sound the same.
To test how tVNS might affect language acquisition, researchers recruited a group of 36 adults who were native English speakers and had them listen to and try to identify four different Mandarin tones - a task similar to English speaking people who don't do this can be particularly difficult.
At the end of the training, these participants were, on average, 13 percent better at classifying sounds than the other participants. Vagus nerve stimulation allowed research participants to pick up some Mandarin tones twice as quickly.
Using painless electrical impulses, this device can stimulate the brain's vagus nerve
Fernando Llanos, a postdoctoral researcher at the Sound Brain Lab at the University of Pittsburg and lead author of the study, says that demonstrating the effectiveness of tVNS in this area could prove beneficial for cognitive learning in general.
“Demonstrating that non-invasive peripheral nerve stimulation can facilitate language learning potentially opens the door to improving cognitive performance in a variety of areas,” explains Llanos.
The researchers suggest that tVNS promotes learning by enhancing neurotransmitter signals in wide areas of the brain to temporarily focus attention on the presented auditory stimulus and promote long-term learning. Further research is needed to test this mechanism.
“We demonstrate large learning effects in a completely non-invasive and safe manner, potentially allowing the technology to be scaled to a broader range of consumer and medical applications, such as post-stroke rehabilitation,” said co-author Bharath Chandrasekaran. “Our next step is to understand the underlying neural mechanism and determine the ideal set of stimulation parameters that can maximize brain plasticity. We view tVNS as an effective tool that can improve rehabilitation for individuals with brain damage.”
Referenz: npj Science of Learning, 2020;DOI: 10.1038/s41539-020-0070-0
