Prolonged hearing loss significantly impacts language retention, as demonstrated through the experiences of postlingually deafened Yoruba speakers who have lost their hearing for over twenty years. These individuals continue to communicate in Yoruba from memory, relying on lip reading, yet exhibit phonological, lexical, and syntactic losses similar to those of young children acquiring the language. The study establishes a connection between language deterioration and first language acquisition, also documenting the unique sign language and gestures developed by these speakers. This research is essential for various fields, including linguistics and deaf studies.
