Neural differences between monolinguals and early bilinguals in their native language during comprehension

Area of Science:

• Neuroscience
• Cognitive Science
• Psycholinguistics

Background:

• Bilingualism is associated with enhanced neural activity in language processing compared to monolingualism, particularly in the inferior frontal gyrus.
• Previous research focused on semantic processing, leaving the neural underpinnings of grammatical processing in bilinguals less explored.

Purpose of the Study:

• To investigate whether semantic and grammatical sentence processing engage distinct cerebral structures in bilinguals compared to monolinguals, specifically within their native language.
• To extend previous findings by examining neural activity during both semantic and grammatical judgments in Spanish/Catalan bilinguals and Spanish monolinguals.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to scan participants while they performed grammatical and semantic judgments in Spanish.
• The study included highly proficient Spanish/Catalan bilinguals and Spanish monolinguals as participants.

Main Results:

• Bilinguals exhibited greater cerebral activity in language-related regions, including the superior and middle temporal gyri, for both semantic and grammatical judgments compared to monolinguals.
• These observed neural differences in brain activation were not accompanied by significant differences in behavioral performance between the two groups.

Conclusions:

• Early bilingualism influences brain structure and cognitive processes involved in native language sentence comprehension.
• The findings suggest that increased brain activation in bilinguals is not limited to a single brain region and extends to various language processing areas.