- Different countries have different sign languages.
Why should there be more than one sign language? Doesn’t that just complicate things? This question would make sense if sign language was a system invented and then handed over to the deaf community as an assistive device. But sign languages, like spoken languages, developed naturally out of groups of people interacting with each other.
- Sign language does not represent spoken language.
Because sign languages develop within deaf communities, they can be independent of the surrounding spoken language. American Sign Language (ASL) is quite different from British Sign Language (BSL), despite the fact that English is the spoken language of both countries.
That said, there is a lot of contact between sign language and spoken language (deaf people read and write or lipread in the surrounding language), and sign languages reflect this. English can be represented through fingerspelling or artificial systems like Signed Exact English or Cued Speech. But these are codes for spoken or written language, not languages themselves.
- Sign languages have their own grammar.
There are rules for well-formed sentences in sign language. For example, sign language uses the space in front of the signer to show who did what to whom by pointing. However, some verbs point to both the subject and object of the verb, some point only to the object, and some don’t point at all. Another rule is that a well-formed question must have the right kind of eyebrow position. Eyebrows should be down for a who-what-where-when-why question, and up for a yes/no question. If you use the rules wrong, or inconsistently, you will have a “foreign” accent!
- Children acquire sign language in the same way they acquire spoken language
The stages of sign language acquisition are the same as those for spoken language. Babies start by “babbling” with their hands. When they first start producing words, they substitute easier handshapes for more difficult ones, making for cute “baby pronunciations.” They start making sentences by stringing signs together and only later get control of all the grammatical rules.
- Brain damage affects sign language in the same way it affects spoken language.
When fluent signers have a stroke or brain injury, they may lose the ability to sign, but not to make imitative or non-sign gestures. They may be able to produce signs, but not put them in the correct grammatical configurations. They may be able to produce sentences, but with the signs formed incorrectly, creating a strange accent. They may be able to sign quickly and easily, but without making any sense. Neurologically, making gestures is quite different from using sign language.
- Sign language is a visual language.
This one is pretty obvious, but it’s important to mention. Sign language is just like spoken language in many ways, but it’s also different. Sign can be very straightforward and formal, but it can also take full advantage of its visual nature for expressive or artistic effect. Which, when you think about it, doesn’t make sign language all that different after all. For expressive purposes, we can take full advantage of spoken language’s auditory nature. We can also take advantage of facial expressions and gestures when we speak. Everything that would be in an artistic spoken performance—the words, the ordering of clauses, the pauses, the breath intake, the intonation and melody, the stressing or deemphasizing of sounds, the facial and vocal emotion, the body posture and head and hand gestures—come through together in sign language.
- Sign language can vary even in the same region
As found in all human languages (both signed and spoken) observed by linguists, language naturally changes over time and geography. It also varies from person to person, across regions, and situations.
Variation is commonly defined as “a different way of saying the same thing” (e.g. “pop”, “soft drink”, and “soda” for the same thing or meaning). There are different types of variation: phonological, regional, gender-related, and few other types.