The focus of the proposed research plan is the documentation and description of the home sign systems used by RCM (age 28), living in Nueva Vida, Peru and ST (age 65) living in Totoya, Peru. Neither RCM nor ST have access to deaf education or an established sign language, yet both individuals use gestural communication systems to converse with family and friends. Through pilot work, the PI found that RCM's system displays grammatical complexity, such as spatial modulation of action signs, verbal argument structure and lexical consistency, that has not previously been observed in a home sign system. At this point, it is unclear how these features could have developed in the system of a single individual. By working with both RCM and ST, it can be established if RCM's system is a true home sign system and if the cultural attitudes of the Mjuna toward deafness aided in the development of such a complex system or if RCM and ST are two users of a single communal home sign, separated by time and space but connected through a community of speakers. Three main questions will be addressed in the research: 1) What level of grammatical complexities exist in RCM and ST's systems and how similar are the two systems? 2) How well do hearing signers adhere to the grammatical features identified in RCM and ST's systems and how consistent are they? and 3) Are RCM and ST's systems related? These questions will be explored through a variety of elicitation and experimental methods. Questions 1 and 2 will be addressed through analysis of prompted conversation, narratives and elicitation of specific grammatical structures using visual stimuli (videos and images). These productions will be coded and analyzed for structural consistency. Experiments using visual stimuli will be used to test comprehension and production consistency between the deaf and hearing consultants. These experimental methods will be used both to test mutual comprehension between signers, as well as internal consistency of the signer, by testing the comprehension of a signer's own productions. In order to answer question 3, data collected from RCM and ST using the previously mentioned methodology will be compared to establish the similarity of lexical signs as well as grammatical structures. As unrelated sign languages can have similarities due to iconicity, strict criteria for establishing relations between the sign systems will be adhered to. The analysis of home sign systems has implications for deaf education. Most deaf children are born to hearing parents. Some parents cannot, or choose not to, expose their children to a signed language, instead encouraging their children to speak. If those children are unable to acquire the spoken language, they enter school largely without language. However, many of these children have developed home signs within their family. Furthering the understanding of home sign systems gives us tools to aid such children in their transition to a conventional language, whether signed or spoken.
Deaf children born to hearing parents often do not begin acquiring a spoken or signed language until they are school-aged, though they may develop a home sign system ? a language-like gestural communication system ? to use with family members. Children who reach adulthood without acquiring a conventional language are rare, necessitating fieldwork in remote areas, such as the Amazon, where deaf individuals have no access to schooling or audiological services. The study of adult home sign systems will inform us about the contributions that deaf individuals can make to the emergence of new sign languages and may aid educators and therapists in transitioning home signing deaf children to a conventional language, whether signed or spoken.