People who are deaf-blind do not necessarily totally deaf or totally blind. Deaf-blindness have a combination of hearing and vision loss. The degrees of hearing and vision loss may vary person to person.
Individual Causes of Deafness and Blindness.
Usher Syndrome is said to be the cause of half the cases of deaf-blindness. Usher Syndrome is a genetic condition in which a person is born hard of hearing or deaf and loses their vision later in life.
There are cases where a person is born deaf-blind but many cases where someone is either deaf or blind and becomes deaf or blind later in life. For people who are deaf-blind they are able to see enough to communicate using sign language. Others are able to use tactile sign-language if they are unable to see.
To learn more about the causes of deafness, read AudioEye’s article about Hearing Impairments and to learn more about the causes of blindness, read AudioEye’s article about Blindness.
People who are deaf-blind use the same resources as others with assistive technology. People who are deaf-blind use screen readers to access content but they have additional technology to process the content information. Screen readers normally verbalize the text but people who are deaf-blind connect refreshable braille displays to their computers. The refreshable braille display works with the screen reader to convey the content to the end user. Depending on the braille display, they have the capacity to provide anywhere from 20 to 80 characters at a time. As the screen reader conveys the information, the braille keyboard pushes small pins up through holes to form Braille characters for the end user to read. The user can press a button for the pins to go down and come up reading new lines of text.