Navigating through the world was once more difficult for the deaf. In the time of Aristotle, to be deaf meant to be a non-person, without the right to learn, marry, or buy land. Aristotle argued spoken language was the only pathway to learning, thus the deaf should be unable to be educated. However, Italian physician George Cardano was propelled to challenge this in the Renaissance. He discovered his son could learn through writing. It was possible to teach those who cannot hear!
In 1960 Spanish priest Juan Pablo Bonnet honed a groundbreaking method of teaching the deaf through his published work “Reduction of the Letters of the Alphabet and Method of Teaching Deaf-Mutes to Speak”, which led to the invention of the sign language. Readers learned to verbally speak through finger positions and text symbolizing the alphabet. Bonnet believed early training was vital to education for the deaf and advised each person in the home to use the manual with the child. Furthermore, Abbe Charles Michel de L’Epee established the first deaf school in France in 1771 called the National Institute for Deaf-Mutes where children could travel from all around France to attend after learning signs from their manuals.
Language is an innate human ability, even for the deaf. Deaf babies babble with their hands similarly to how others normally do with voice. A baby can learn sign language as early as 6 months, when the children typically begin to speak at 11-13 months. In fact, the Penn State College of Medicine treated a baby’s apraxia with sign language as a bridge to speech! Apraxia is a rare speech disorder affecting the accuracy of speech due to the brain struggling to coordinate the lips, jaw, and tongue. After treatment, the speech therapist and parents understood up to 90 percent of what the baby said. He used sign language less until his speech finally developed. This is important in early intervention because apraxia is diagnosed around 2 years of age.
People would be surprised to hear there are many benefits to teaching their child sign language, including that it:
Gives pre-verbal child ways to communicate
Aids child’s understanding of language
Increases communication opportunities
Decreases child’s frustration
Decreases caregivers’ frustration & confusion
Strengthens emotional bond
Helps child learn that movements have meaning
Families may find it fascinating that our closest animal cousins also found sign language useful!
Like human children who learn most words between the ages of 2 and 4, Koko the gorilla’s fastest pace in learning was between 2.5 and 4.5. At age 11, Koko could understand 800 words. After, she learned over 1,100. Koko had a companion Michael who learned at about the same pace. They could communicate with one another and express abstract concepts and tell stories about past events. Both gorillas learned to comprehend people and respond accordingly. They even learned how to understand a large amount of spoken language. Both Koko and Michael could understand 2,000 words. Visitors were caught by surprise when the two responded to their side comments. Koko is also able to respond with emotional depth about a sad movie.
Sometimes Michael and Koko wanted objects or activities they did not have words for. Then, they invented compound words out of two or more signs they did know. Koko combined SCRATCH and COMB for “brush” (SCRATCH-COMB). She even added the letter “s” at the end of “brow” to make up a sign for “browse”. This was a word the caregivers used for greens and flowers gathered for snack. The gorillas made sign language of up to 8 or more words. These would include consistent grammatical structure. Sometimes the gorillas would modify their signs to be bigger/smaller or faster/slower or in a different location to indicate feeling, emphasis, or difference in meaning.
Everyone deserves a voice. When hands start to speak, our communication becomes all the more powerful. Currently, there are up to 300 different types of sign language used today and sign language is used to tell jokes, ask riddles, express sarcasm, create idioms, make poetry, etc. These abilities are priceless, and new sign languages evolve frequently among groups of deaf children and adults. For these reasons, we can say that sign language is as important as spoken language. Although Koko passed away at 46 in 2018, with over four decades of using signs to play with humans, she would probably agree.
Sign Language. (n.d.). Retrieved from
Apraxiaadmin. “What About Sign Language, Speech Tablets, and Other Communication Forms?”
Penn State College of Medicine. (2016, September 1). Sign language may be helpful for children with rare
speech disorder. ScienceDaily. Retrieved February 6, 2020 from
KCDHH. “Sign Language History”