Being Bilingual May Help to Delay Cognitive Decline in MS, Study Suggests

An ability to speak more than one language may help to protect people with multiple sclerosis (MS) against the cognitive decline caused by the disease, new research suggests.

The study, “Multiple sclerosis and bilingualism: Some initial findings,” showed that MS patients who speak two languages (bilingual speakers) score better on cognitive tests than patients able to converse in only a single tongue (monolingual). It was published in the journal Linguistic Approaches to Bilingualism.

Speaking two languages, or bilingualism, is thought to benefit executive function — the set of cognitive processes necessary for goal-directed behaviors. As such, it is believed this ability might work to delay in a person the onset of symptoms associated with degenerative diseases.

One recently published study, for instance, found that MS patients in Austria who took part in an eight-week English language course showed healthy changes in gray matter volume in certain brain areas, measured on imaging scans.

A study led by researchers at the University of Reading, in the U.K., and Hospital Universitario Gregorio Marañón, in Spain, investigated how bilingualism affected cognitive function in people with MS, a disease that is commonly associated with problems in cognition (e.g., difficulties finding the right words, remembering things, or making decisions).

“This is the first study that we’re aware of that has tested the idea that there is an advantage for bilinguals when it comes to neurodegenerative diseases such as MS,” Fraibet Aveledo, PhD, a lecturer in child language development and bilingualism at the University of Reading, and the study’s first author, said in a press release.

“While most studies analyse clinical records of patients with dementia, our study has directly compared four groups of people and reveals a significant cognitive boost for MS patients who speak multiple languages compared to their single language peers,” Aveledo added.

Researchers looked at groups of bilingual and monolingual MS patients, matched for similar levels of cognitive abilities, recruited at Gregorio Marañón Hospital in Madrid.

Participants were asked to perform a Flanker task, cognitive test that assesses executive functions called ‘monitoring’ (which refers to the ability to keep track of one’s behavior) and ‘inhibitory control’ (the capacity to control oneself and suppress irrelevant behaviors, so as to do act appropriately in a particular context).

Results showed that bilingual MS patients and healthy subjects performed similarly on the tests, while monolingual patients scored significantly worse than people without MS, particularly on the ‘monitoring’ task.

In light of their findings, researchers proposed that speaking two languages “might counteract cognitive deficits related to MS, especially with respect to monitoring,” and added that the findings “provide some preliminary evidence for the cognitive reserve hypothesis in bilingual MS patients.”

The cognitive reserve theory postulates that people with greater cognitive reserve — the flexibility a person’s brain has in allocating cognitive resources, which depends on genetics and lifetime exposure to environmental factors such as education — are able to cope better with damage to the brain. Essentially, they can withstand more advanced disease before experiencing the difficulties that a person with poorer cognitive reserve would exhibit at earlier disease stages.

“The exciting thing about this study is that it demonstrates for the first time the benefits of bilingualism, including having a preventative effect against cognitive decline in MS,” said Christos Pliatsikas, PhD, a professor in psycholinguistics at the University of Reading.

“People with MS want to work to improve their daily-basis functioning, and studies like this one offer new information about how to build-up their cognitive reserve from early stages,” added Yolanda Higueras, PhD, a neuropsychologist in the MS Unit at Gregorio Marañón Hospital.