Researchers found that learning a second language later on in childhood after gaining proficiency in a first language modified the brain’s structure, specifically the inferior frontal cortex.
Using a software program developed at The Neuro, the Montreal Neurological Institute and Hospital at McGill University, researchers examined magnetic resonance imaging scans of 66 bilingual and 22 monolingual men and women living in Montreal.
Working with researchers from Oxford University, the research team concluded that the pattern of brain development is similar if you learn one or two languages from birth.
However, in those who learned a second language later on in childhood, they found that the left inferior frontal cortex became thicker and the right inferior frontal cortex became thinner.
The cortex is a multi-layered mass of neurons that plays a major role in cognitive functions, such as thought, language, consciousness and memory.
The findings suggests that the task of acquiring a second language after infancy stimulates new neural growth and connections among neurons, according to the researchers. They noted that these changes are similar to those seen in people who acquire complex motor skills, such as juggling.
The researchers speculate that the difficulty that some people have in learning a second language later in life could be explained at the structural level.
“The later in childhood that the second language is acquired, the greater are the changes in the inferior frontal cortex,” said Denise Klein, Ph.D., a researcher in The Neuro’s Cognitive Neuroscience Unit and a lead author of the study.
“Our results provide structural evidence that age of acquisition is crucial in laying down the structure for language learning.”
The study was published in the journal Brain and Language.