User:Jnb21/sandbox

In 1620, Juan Pablo Bonet published Reducción de las letras y arte para enseñar a hablar a los mudos ('Reduction of letters and art for teaching mute people to speak') in Madrid. It is considered the first modern treatise on phonetics and speech therapy, setting out a method of oral education for deaf children by means of the use of manual signs, in the form of a manual alphabet to improve communication with the deaf. It is suggested that Pedro Ponce de León developed the first manual alphabet from which Juan Pablo Bonet based his writings. Wyatte C. Hall says that sign language is important for the development of Deaf children growing up because without it, they could be at risk of many health difficulties. Studies have shown that the development of neuro-linguistic structures of the brain can be affected if there is a language delay. A study showed that there is an “age of acquisition” that affects adults' ability to understand grammar based on when they were introduced to sign language (Mayberry, R. I.).