Tactile sign language is most often used by people who are deafblind, meaning they both cannot hear and cannot see. Instead of traditional sign languages (like ASL in English or LSF in French), the tactile sign language is understood by an individual using their hands to understand, via touch senses, what another person is communicating.
The origins of tactile sign language are quite recent. While sign language itself evolved over hundreds of years, deafblind people were often forced to live in isolation. Around the 1970s, efforts were made by multiple institutes for the deaf or blind to create a form of communication for deafblind people.
It’s important to note that tactile sign language is its own form of communication, separate from visual sign languages like ASL or LSF. Someone can communicate using visual sign languages, made tactile by the ‘hand over hand’ method, where an individual places their hands over top of the communicator’s hands while they are signing in order to understand what is being communicated. This is most often used by people who lost their ability to hear first but learned visual signing before losing eyesight due to a different condition.
Other methods have also been developed such as tracking, where an individual places their hands on the wrists of the communicator to feel them track signs visually, and tactile fingerspelling, where the communicator traces letters or signs onto the palm of the deafblind person. Further, on-body signing is used to communicate with people who are born deafblind or who have intellectual disabilities and cannot adequately learn hand-based tactile methods.
Because hearing and vision loss are both on a spectrum, some deafblind people are able to communicate in other ways, for example using a brailler with some tactile elements. That said, tactile sign language in all its forms remains the primary way that deafblind people communicate.
Deafblindness impacts an estimated 15 million people globally, but there are few public figures with deafblindness. One of the most famous examples is Helen Keller, the 20th century American novelist, disability advocate, and political activist. After losing her sight and hearing abilities as an infant, she learned to communicate through tactile fingerspelling and went on to use a modified typewriter to write books, pamphlets, and articles advocating for people with disabilities.