Second language acquisition (SLA) research offers valuable insight on how languages are learned and how they coexist and influence each other. Sign language learners offer unique perspectives on SLA, allowing researchers to test theories that are otherwise constrained by access to only one modality. Current literature on sign language learning focuses primarily on bimodal bilinguals, mostly hearing adults learning their first sign language (M2L2 learners). However, other groups of L2 signers exist, including deaf learners who have previously acquired a sign language and are learning a new one (M1L2 learners). M1L2 acquisition offers unique insights into complex interactions including multilingualism, modality, and timing of acquisition. We argue that M1L2 signers are a key comparison group for investigations of various L2 and so-called modality effects and also represent a crucial test case for re-examining the traditional constructs of “native speaker/signer” and the effects of initial language delay or deprivation on subsequent language acquisition.

中文翻译：

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模态在 L2 学习中的作用：学习者获得第二手语的重要性（M2L2 和 M1L2 学习者）

第二语言习得 (SLA) 研究提供了有关语言如何学习以及它们如何共存和相互影响的宝贵见解。手语学习者提供了关于 SLA 的独特视角，使研究人员能够测试那些因只能使用一种模式而受到限制的理论。目前有关手语学习的文献主要关注双模态双语者，其中大多数是学习第一手语的听力正常的成年人（M2L2 学习者）。然而，还存在其他 L2 手语者群体，包括之前已经获得手语并正在学习新手语的聋哑学习者（M1L2 学习者）。M1L2 习得为复杂的交互提供了独特的见解，包括多语言、模式和习得时间。我们认为，M1L2 手语者是研究各种 L2 和所谓模态效应的关键比较群体，也代表了重新审视“母语者/手语者”的传统结构以及初始语言延迟或语言延迟的影响的关键测试用例。剥夺随后的语言习得。