Home sign

Because the deaf child does not receive signed or spoken language input, these children are considered linguistically isolated.

[2][3] Because home sign systems are used regularly as the child's form of communication, they develop to become more complex than simple gestures.

Home sign systems display significant degrees of internal complexity, using gestures with consistent meanings, word order, and grammatical categories.

Linguists have been interested in home sign systems as insight into the human ability to generate, acquire, and process language.

[7][page needed] Across users, these systems tend to exhibit a stable lexicon, word order tendency, complex sentence usage, and noun-verb pairs.

[8][9] Studies of home signing children and adults show consistent pairing between the form of a gesture token and its meaning.

The emergence of a conventionalized lexicon proceeds slower in a home sign system than in natural languages with a richer social network.

[13] Study of adolescent home signers show ability to express motion events, though this strategy differs from conventional sign language.

Though caregivers' co-speech gestures may serve as an initial foundation for their child's home sign system, children surpass this input.

[19][20] Social network structure influences the development of a home sign system, impacting the conventionalization of referring expressions among members.

In comparison to unschooled hearing and signing deaf individuals, adult home signers do not consistently produce gestures that accurately represent cardinal values of larger sets and do not exhibit effective use of finger counting strategies.

[25] Syntactic structure is similar between groups of home signers in different cultures and geographical regions, including word order preferences and complex sentence usage.

For example, home sign systems of children in Turkey and the United States exhibit similar patterns in sentence-level structure.

However, most young children use the head shake as an initial marker of negation, and replace it with speech or manual signs once language is acquired.