Wendy Callis’s “mesmerizing” work during Hurricane Sandy called attention to how facial and body movements are parts of grammar in the visual language.

As New York City Mayor Bloomberg gave numerous televised addresses about the preparations the city was making for Hurricane” Sandy, and then the storm’s aftermath, he was joined at the podiumby a sign language interpreter, who immediately became a twitter darling. People watching the addresses tweeted that she was “amazing,” “mesmerizing,” “hypnotizing,” and “AWESOME.” Soon, her name was uncovered — Lydia Callis — and animated GIFs of her signing were posted. A couple of hours later, a tumblr was born. New York magazine called her “Hurricane Sandy’s breakout star.”

Callis was great, but not because she was so lively and animated. She was great because she was performing a seriously difficult mental task — simultaneously listening and translating on the spot — in a high-pressure, high-stakes situation. Sure, she was expressive, but that’s because she was speaking a visual language. Signers are animated not because they are bubbly and energetic, but because sign language uses face and body movements as part of its grammar.

In American Sign Language, certain mouth and eye movements serve as adjectival or adverbial modifiers.

In this example, Bloomberg is explaining that things will get back to normal little by little. Callis is making the sign INCREASE, but her tight mouth and squinting eyes modify the verb to mean “increase in tiny increments.” This facial expression can attach to various verbs to change their meaning to “a little bit.”

Via: http://www.theatlantic.com/health/archive/2012/11/why-great-sign-language-interpreters-are-so-animated/264459/