Signed languages make unique demands on gaze during communication.
Bilingual children acquiring both a spoken and a signed language must
learn to differentiate gaze use for their two languages. Gaze during
utterances was examined for a set of bilingual-bimodal twins acquiring
spoken English and American Sign Language (ASL) and a set of
monolingual twins acquiring ASL when the twins were aged 2;0, 3;0
and 4;0. The bilingual-bimodal twins differentiated their languages by
age 3;0. Like the monolingual ASL twins, the bilingual-bimodal twins
established mutual gaze at the beginning of their ASL utterances and
either maintained gaze to the end or alternated gaze to include a terminal
look. In contrast, like children acquiring spoken English monolingually,
the bilingual-bimodal twins established mutual gaze infrequently for
their spoken English utterances. When they did establish mutual gaze,
it occurred later in their spoken utterances and they tended to look away
before the end.