The Biological Effects of Multilingualism on the Mind
- Diya Jafari
- 6 days ago
- 4 min read
Introduction
Language is not exclusively a vessel of history, culture and social identity, rather it extends further, deep into the brain, altering its makeup and significantly enhancing cognitive ability. 60% of the world’s population is made up of polyglots hence, 60% of the population has increased neuroplasticity, the brain’s ability to modify itself 2. Learning languages is one of the greatest ‘mental workouts’, strongly linked to the delay of mental conditions such as Alzheimer's and dementia 3, it continues to improve connections and quality of life.
How the brain processes language
Bonjour. Ciao. Hello. These words have just activated the Wernicke’s area of your brain. Located in your left temporal lobe it’s responsible for language comprehension 1. The main components of your brain that digest language are the Broca’s and Wernicke’s areas, located in the left frontal and temporal lobes. The Broca’s area, responsible for speech production and articulation 1. Research suggests that the Broca’s area is functional during silent reading, specifying its role in language comprehension and internalisation. It coordinates mental ideas with physical actions. Other research suggests that motor neurons are contained within the Broca’s area. These neurons fire when we complete an action or observe someone else completing the same action. This may explain its position in speech and gesture based communication. 4
The Wernicke’s area of the brain is considered to be the receptive language region of the brain. Although in close proximity, the Wernicke's and Broca's area both serve independent functions. Wernicke's area is responsible for language comprehension. In collaboration with the auditory cortex, it aids in the comprehension of both written and spoken language comprehension by turning sounds and symbols into meaning. Additionally, it plays a large role in semantic processing, which is the ability to link words with their respective meanings and identify relationships. The Broca’s and Wernicke’s areas interlinked through a bundle of nerve fibres called arcuate fasciculus. When we hear language, it’s construed by the Wernike’s area where it’s interpreted and a signal is sent to the Broca’s area allowing comprehensible communication. 5
The physical effects of bilingualism
MRI scans reveal an enlargement of the hippocampus, the centre for memory and learning, in bilingual individuals. This volume increase was later confirmed by researchers to be due to studying a second language as a young adult. Another study further proved the increase of white and grey matter in the brains of those enriched with languages. Increased white matter pathways lead to improved linguistic proficiency, cognitive flexibility and long-term cognitive benefits. Grey matter, linked with information processing, also increased in individuals with higher linguistic education than those of their monolinguistic counterparts. Overall, languages increase neuroplasticity and cognitive flexibility. 6
But what is neuroplasticity and cognitive flexibility? Neuroplasticity is the brain's ability to process information and adapt. It can bring physical changes inside your brain as your brain essentially undergoes a process of ‘rewiring’ itself to adapt to your external conditions. However, neuroplasticity isn’t simply about learning new things, it’s your brain’s ability to regrow and repair itself, especially critical after events such a stroke or traumatic brain injury. 7. Cognitive flexibility is the brain's ability to switch between thinking about different concepts or reconstructing at the intake of new information. 6. It often takes place during changing circumstances or when encountering challenging problems. A common demonstration of cognitive flexibility is multitasking. The brain is rapidly moving through different tasks and requirements all at once. 8
The delay of mental disease
Research has shown that learning a second language has prevented the onset of mental disease such as Alzheimer’s by 4.5 years. It’s suggested by researchers that due to the larger cognitive reserve of polyglots, their brains are more rigid towards diseases such as Alzheimer's. 9. Learning languages is a workout for your brain, similar to lifting weights to exercise your arms.
Conclusion
Overall, speaking more than one language provides the mind with immense benefits. By growing the brain and neural pathways, it serves as an armour, protecting the brain from disease and shielding it during times of cognitive difficulty. As a whole, learning a second language provides more benefits than harm. It’s a skill that everyone should have to maximise quality of life and cognitive function.
1
Andrews, Chloé. 2019. “What Happens to Your Brain When You Learn a New Language? - Unbabel.” Unbabel. February 19, 2019. https://unbabel.com/what-happens-to-your-brain-when-you-learn-a-new-language/.
2
MSEd, Kendra Cherry. 2025. “How Neuroplasticity Works.” Verywell Mind. October 23, 2025. https://www.verywellmind.com/what-is-brain-plasticity-2794886.
3
St. Augustine College, The Cognitive Benefits of Being Bilingual: St. Augustine, February 2, 2026, December 17, 2025
4
Simply Psychology, Broca's Area of the Brain: Function and Location, February 2, 2026, May 06, 2025
5
Simply Psychology, Wernicke's Area: Location and Function, February 2, 2026, June 11, 2025,
6
N, May, and May N. 2024. “How Language Learning Reshapes Neural Pathways: A Journey Through the Brain’s Transformation.” Liberty Language Services. August 29, 2024. https://www.libertylanguageservices.com/post/how-language-learning-reshapes-neural-pathways/.
7
Clinic, Cleveland. 2023. “Brainwork: The Power of Neuroplasticity.” Cleveland Clinic. December 13, 2023. https://health.clevelandclinic.org/neuroplasticity.
8
“Cognitive Flexibility | Religion and Philosophy | Research Starters | EBSCO Research.” n.d. EBSCO. https://www.ebsco.com/research-starters/religion-and-philosophy/cognitive-flexibility.
9
Alzheimer’s Research UK. 2024. “Speaking a Second Language Shows Benefits in Alzheimer’s - Alzheimer'S Research UK.” March 4, 2024. https://www.alzheimersresearchuk.org/news/speaking-second-language-shows-benefits-alzheimers/.
Comments