SCIENCE How the Bilingual Brain Switches Languages With Ease Similar concepts in different languages share an

• Bilingual brains map equivalent concepts from different languages to the same neural “address” (a shared semantic geometry), so meaning — not language — guides activation across languages [Rice News].
• Individual neurons can prefer one language, but larger neural networks preserve language-independent relationships between concepts, enabling easy switching [SingularityHub].
• Bilinguals recruit the same language-combination regions as monolinguals when building phrases, so switching feels seamless because the brain uses shared processing machinery for meaning and syntax [Rice News; Scientific American].

Follow-up Questions:

1. How did researchers measure the “shared semantic geometry”?

2. Does age of acquisition affect how languages are represented in the brain?

3. Can this shared mapping explain bilingual tip-of-the-tongue errors or code-switching?

4. Do literacy or writing systems change the neural overlap between languages?