The debate surrounding the advantages and disadvantages of bilingualism for children has been pitting linguists and psychologists for nearly 100 years old. Back then, most experts believed that bilingual children were doomed to suffer cognitive impairments later in life. But the science has marched on.
The early myths surrounding bilingualism originated in studies in the US and the UK from the two world wars. Unfortunately, these studies had serious flaws. The subjects were children of war; refugees and orphans who suffered trauma and whose education was disrupted for years.
Not to anyone’s surprise, these children performed quite poorly on the language tests they were given. However, did any of the researchers stop to consider the impact of PTSD on these children? How could they? PTSD was relatively unknown at the time, so instead the poor results were attributed to the children’s bilingualism.
The Case Against Bilingualism for Children
The primary concern regarding bilingual children in the ensuing confusion as a result of learning two languages simultaneously. How could this young child avoid the practically guaranteed confusion that will result from mixing the languages? So instead of being adept at two languages, the child probably won’t be competent in even one!
The McGill Study that turned things around
In the1960s, a landmark study was published by Elizabeth Peal and Wallace Lambert at McGill University in Montreal, that was seminal in causing the views of bilingualism in children to shift.
The McGill study showed that contrary to the accepted belief that bilingual children will suffer a cognitive delay or a longer-term deficit, that their bilingualism can benefit the children in their cognitive development!
Benefits were demonstrated both regarding improved executive function as well as metalinguistic awareness, which is the capacity to conceive of language regarding abstract units and associations.
Improved Executive Function
Executive Function is the umbrella term that refers to those skills that allow a person to control, direct and manage their attention. It also includes the ability to filter out what is irrelevant, focus on what is relevant, and the ability to plan.
People who are bilingual are mastering two languages simultaneously. Such mastery is activated automatically on the level of the subconscious. In other words, the bilingual person is in a mode of constantly managing the interference of the languages. This is necessary so that the wrong word in the wrong language isn’t said at the wrong time.
These filtering and organizational skills are among the most complex brain functions that exclusively human beings perform. The “processing center” is the prefrontal cortex, which is the part of the brain responsible for advanced processing; the bilateral supramarginal gyri, which play a role in linking words and meanings; and the anterior cingulate.
Research has shown that being bilingual alters brain structure as a result of these necessary accommodations. In other words, the benefits of being bilingual aren’t temporary but rather long-term serving that child well into adulthood!
Enhanced Brain Development
Neurons, the cells in the brain contain little branching connections called dendrites. Gray matter refers to how many cell bodies and dendrites there are. Brain scans have shown that bilingualism increases the density of the gray matter- in other words; it promotes the creation of brain cells.
Bilingualism increases white matter in the brain as well. This white matter is a fatty substance that covers axons optimizing the connections between neurons, allowing messages in the brain to travel quicker and more efficiently across the brain and neural networks.
So it seems that contrary to what was initially believed about bilingualism in children may not be true at all. Exposing this myth may have far-reaching implications for the children of immigrant and bilingual families, their speech therapy needs, and the language strategies needed to be designed to enhance their development.