Researchers have demonstrated for the first time that the beneficial effects of multilingualism on autism symptoms in children are connected to improved executive functioning — a set of cognitive skills used in everyday tasks such as planning, problem solving, retaining information, and adapting to new situations.

“As a first-generation American, and the daughter of immigrant parents, my native language is deeply tied to my identity and family connections,” explained Celia Romero at the University of Miami and lead author of the study in an email.  “I was shocked to learn that many families are advised against raising their [autistic] child in a bilingual environment, despite no evidence that bilingualism hinders cognitive or language development.”

This, says Romero, is problematic as limiting a child’s exposure to something like their parent’s native language can disrupt family bonds and does, in fact, impact social development.

Challenging these common misconceptions, Romero and her colleagues set out to investigate whether the “bilingual advantage,” the idea that being able to speak more than one language improves cognitive abilities, is true for children with autism.

“Our study found that children with [autism] who are exposed to multiple languages tend to have stronger executive function skills, including better control over their actions and greater ability to switch between tasks, compared to children with [autism] who speak only one language,” Romero said.  

“I hope our research sheds light on this issue and sparks more studies that provide families with the guidance they need to make informed decisions about language use in the home,” she added.

Autism, language, and dispelling fears

Autism is a neurodevelopmental condition marked by core symptoms that include difficulties in socialising and communicating, and exhibition of obsessively repetitive behaviours such as arm flapping or rocking.

Scientists believe these symptoms are intrinsically linked to the brain’s ability to carry out executive functioning skills, which include the ability to practice inhibition and understand the perspective of others.   

“While much research has explored these factors individually, our study highlights how multilingual exposure may influence not just cognitive skills, like task-switching and self-control, but also social abilities […] in children with autism,” said Romero.  

Collaborating with researchers at the University of California Los Angeles (UCLA), Romero studied 112 autistic and typically developing children aged 7-12 years old. Of this population, just under half were autistic, and of the autistic individuals, about 40% spoke more than one language.

Parents were asked to complete questionnaires as a means of measuring the degree of autism symptoms their children displayed. These parents, and those of typically developing children, also completed questionnaires that were designed to specifically measure the executive functioning skills of their children. The researchers then compared autism symptoms between monolingual and multilingual autistic children, and performed a further statistical analysis known as a “mediation analysis.”

“Mediation analysis helps us see if the relationship between two variables [in this case, multilingualism and autism symptoms] is explained by a third variable,” explained Romero. “One strength of this approach is that it helps us understand how multilingualism might be associated with [autism], rather than simply identifying that a relationship exists.”

A simple association indicates there is a relationship between two factors but does not explain why or how they are related. What mediation analysis does is take this a step further, suggesting whether this relationship is connected to or explained by a third factor.

Using this analysis, the researchers were able to determine the connection between multilingualism and autism symptoms, finding it is indeed mediated by executive functioning. More specifically, autistic and typically developing children who can speak more than one language tended to be able to practice inhibition, shift their attention, and understand the perspective of others better than those who only spoke one language. Separately, multilingual children had fewer autistic symptoms than those that spoke only one language.

“If you have to juggle two languages, you have to suppress one in order to use the other,” commented Lucina Uddin, professor, and neuroscientist at the University of California Los Angeles (UCLA) and senior author of the study in a press release. “That’s the idea, that inhibition might be bolstered by knowing two languages.”

On to the next level

Despite offering valuable insights, the study findings should be interpreted cautiously.

The statistical analyses cannot prove that multilingualism is the cause of improved executive function and ASD symptoms, only that there is a connection worth exploring.

There could be other unknown factors at play influencing these relationships, such as family language practices, social economic status, and peer social interactions. Parent reported measures of their children’s cognitive abilities and symptoms may also be biased and subjective. Future studies that include more objective performance-based measures of these functions could help address this and refine the data.

Finally, the study’s results are from a relatively small sample size and may not be generalised to the wider population because more data in a larger number of autistic children from diverse cultures and language backgrounds is needed.

Uddin says that the team want to replicate their findings in another study and expand their work to include brain imaging.

“In this new study, we are assessing executive functions in monolingual and bilingual children with autism using a wide range of tests,” said Uddin. “We are also collecting magnetic resonance imaging data to help us better understand how being exposed to multiple languages influences brain development in children with autism. We hypothesize that brain activation and connectivity supporting executive function may be different in multilingual children.”

With such studies to determine underlying mechanisms underway, it is hoped a deeper understanding could further the development of interventions to improve clinical outcomes for these children. Until then, the researchers suggest multilingualism may offer a “natural intervention strategy” to strengthen executive functional skills in autistic children with multilingual backgrounds.

Reference: Romero, C, et al., Multilingualism impacts children’s executive function and core autism symptoms, Autism Research (2024). DOI: 10.1002/aur.3260

Feature image credit: Artem Kniaz on Unsplash