The Bilingual Brain

This topic examines how the brain represents and controls two or more languages and how proficiency and age of acquisition shape that organization.

Definition

The study of the neural representation and control of multiple languages in bilingual and multilingual individuals.

Scope

It covers neuroimaging evidence on whether languages share or recruit distinct neural substrates, the control networks that select languages and manage interference, and how proficiency and age of acquisition modulate brain involvement. It describes the neuroscience rather than advising on language use or education.

Core questions

• Do a bilingual's languages share neural substrates or engage distinct ones?
• What brain networks control language selection and suppress interference?
• How do proficiency and age of acquisition affect neural organization?

Key concepts

• shared versus separate substrates
• language control network
• inhibitory control
• proficiency effects
• age of acquisition

Key theories

Neurocognitive model of language control

Abutalebi and Green's account that bilingual language control recruits a network including prefrontal cortex, anterior cingulate, and basal ganglia to select and inhibit languages.

Proficiency and age-of-acquisition effects

Perani and colleagues' imaging evidence that proficiency, more than age of acquisition, shapes the cortical representation of a second language.

History

Imaging studies from the late 1990s, such as Perani and colleagues' work on proficiency and age of acquisition, and Abutalebi and Green's control-network model in 2007, established the neuroscience of bilingualism as a distinct topic.

Debates

Proficiency versus age of acquisition

Whether differences in how a second language is represented in the brain are driven mainly by proficiency or by the age at which it was acquired.

Key figures

• Jubin Abutalebi
• David Green
• Daniela Perani
• Judith Kroll

Seminal works

• abutalebigreen2007
• perani1998
• krollbialystok2013

Frequently asked questions

Are two languages stored in different parts of the brain?

Largely the same regions support both languages, especially at high proficiency, while additional control regions help select the intended language and manage interference.