The first language filter (or "native language neural commitment") refers to the brain's tendency to process, perceive, and "filter" new sounds and language structures through the established neural pathways of the native tongue. By roughly 8–10 months of age, infants stop being "universal listeners" and begin losing the ability to distinguish non-native sound contrasts, focusing instead on those in their native language.
Here is how this filter impacts hearing and language learning:
Impact on