ISAN-THAI DIGLOSSIA: INTERGENERATIONAL TRANSMISSION AS THE KEY INDICATOR TO VITALITY

Abstract

ABSTRACTIsan-Thai Diglossia: Intergenerational Transmission as the Key Indicator to Vitality Minority languages in diglossic situations with a majority language face the danger of eventual loss of vitality. The first sign of this is when child language acquisition begins to erode. This dissertation investigates the intergenerational transmission of the Isan language, spoken in the Northeastern region of Thailand. While the Isan community believes that their language is robust and not at risk of extinction, there are potential signs of losing its vitality, including loss of vocabulary in certain domains, lower prestige for the language than Thai, amongst others. This dissertation quantitatively assesses various aspects of intergenerational transmission of both Isan and Thai among children in Northeastern Thailand. The dissertation begins by establishing that Isan and Thai are indeed different languages, and not dialects of the same language, as is commonly thought. Tests of mutual intelligibility test developed by Yang et al. (2019) and O’Grady et al. (2022) are used. The main study of this dissertation employs the Tool for Intergenerational Transmission Assessment (TITA, Deen et al., 2017), a suite of instruments designed to measure various aspects of a child’s linguistic environment and their abilities in different language domains. TITA consists of six instruments in total; however, the first five instruments are used in this study. TITA 1 and TITA 2 consist of parental questionnaires. The former uses the Household Language Questionnaire and assesses the language environment that children find themselves in. The latter used the Child Language Questionnaire which gathers parental responses on which languages their child uses and in what domains and capacities. In TITA 4 and TITA 5, children’s ability to comprehend and produce lexical items is assessed in both Isan and Thai using a picture selection task and a picture naming task. TITA 6 addresses whether children have acquired a key grammatical pattern (the passive) equally well in the two languages. We use a picture selection task and elicited production task to assess this. The ultimate results indicate that Thai surpasses Isan in many aspects, and this reveals clear signs of weakness in Isan. Lexical production lags in Isan compared to Thai, and children struggle with comprehension of passive in Isan (though not Thai) as well as production. We conclude that the language of Isan, far from being strong and entrenched, might be on its way to erosion, and may become weaken for its vitality sign in the coming decades. I hope this research will spur further attention to Isan’s preservation and revitalization.