Some concept devices have even used the blinking eye as an interface method.

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Tourette's syndrome is marked by movements such as shoulder shrugging, eye blinking and head jerking, as well as bizarre vocal tics including barking and uncontrollable outbursts of profanity.

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Barking is still his dominant tic, but when he was the age of his campers, he wrestled to control several others, including eye blinking, teeth chomping and arm twitching.

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