Functional Connectivity Reveals Which Language the "Control Regions" Control during Bilingual Production

Area of Science:

• Neuroscience
• Cognitive Science
• Linguistics

Background:

• Bilingualism involves complex language control mechanisms.
• The dorsal anterior cingulate cortex (dACC) and left caudate nucleus (Lcaudate) are implicated in language control.
• Understanding how these regions manage dual-language activation is crucial.

Purpose of the Study:

• To investigate the functional connectivity (FC) of the dACC and Lcaudate in bimodal bilinguals.
• To determine how these regions interact with modality-specific language areas (LSTG for speech, LPCG for sign).
• To explore how FC patterns change in single- vs. dual-language contexts.

Main Methods:

• Functional connectivity (FC) analysis during a picture-naming task.
• Bimodal bilinguals (spoken and signed languages) participated.
• FC was measured between control regions (dACC, Lcaudate) and language-specific regions (LSTG, LPCG) in single- and dual-language contexts.

Main Results:

• In single-language contexts, dACC showed increased FC with the target language region.
• In dual-language contexts, dACC exhibited strong FC with the less proficient (signed) language region (LPCG).
• Lcaudate showed strong FC with LPCG in single-language and LSTG in dual-language contexts.

Conclusions:

• The dACC appears to monitor and support target language processing.
• The Lcaudate seems to control the selection of less accessible languages.
• Language control processes dynamically adapt to varying contextual demands in bilinguals.