Chapter 13
Bilingualism and functional connectivity
The path to efficiency across the lifespan
Four patterns describe how bilingualism affects
the functional connectivity of the brain. First, a general
observation across most of the studies I surveyed was that
bilinguals tended to have higher functional connectivity when
compared to monolinguals. Second, increased connectivity with the
salience network, a set of regions including the anterior cingulate
cortex, the bilateral insula, and subcortical regions is often
associated with language training or language
diversity where proactive attention to content is paramount. Third,
to the degree that individuals have greater exposure or mastery of a
second language, (greater proficiency and an earlier or simultaneous
age of acquisition) and can rely more on reactive control, studies
often show greater bilateral connectivity between the inferior
frontal gyri. This is also sometimes associated with decreased
activation of frontal regions implying distributed load and greater
neural efficiency. The distributed neural pattern in young adulthood
may also explain how bilingual older adults are able to sustain
their cognition at levels of neuropathology most monolinguals cannot
endure. Fourth, in studies that examined anticorrelations between
task and rest networks, bilinguals tended to have more distinct
(e.g., modular organization), and more strongly anticorrelated
task-positive and default-mode networks, and this was often
correlated with cognitive control.
Article outline
- First encounters of the bilingual kind
- Beginning at the end
- Language acquisition, language training, and brain
networks
- Methods for studying functional connectivity
- Brain networks supporting language in children: A promise of things yet to come
- How language training modifies brain networks: The role of plasticity
- Inverting the question: A capacity for language?
- Increasing complexity and density of content for greater
learning
- Interpreter training: Refinement of language systems
- Young adult bilingual brain networks
- Bilateral frontal connectivity: A hallmark of efficiency?
- Scaling bilingualism: Diverse patterns and measures
- Bilingualism’s effect in older age: Returning to the end
- Conclusions and next steps
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Notes
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References