The role of age of acquisition on past tense generation in Spanish-English bilinguals: an fMRI study.

At its most basic sense, the sensorimotor/emergentist (S/E) model suggests that early second language (L2) learning is preferentially reliant upon sensory and motor processes, while later L2 learning is accomplished by greater reliance on executive abilities. To investigate the S/E model using fMRI, neural correlates of L2 age of acquisition were examined by employing a past-tense generation task on 22 L2 proficient bilinguals. Early bilinguals preferentially recruited left hemisphere sensorimotor regions involved in motoric control and articulation. In contrast, later learners, to a greater degree, engaged regions involved in executive cognitive control and lexical access. The data support the notion that early L2 learners devote neural resources to motor control during lexical retrieval. In contrast, later L2 learners recruit executive control mechanisms to generate the past tense. These data are consistent with the S/E model of bilingual language learning, and serve as an extension of cognitive control theories.

从最基本的意义上讲，感觉运动/涌现主义（S/E）模型表明，早期第二语言（L2）学习优先依赖于感觉和运动过程，而后期的L2学习则更多地依赖执行能力来完成。为了使用功能性磁共振成像（fMRI）研究S/E模型，通过对22名精通第二语言的双语者进行过去时态生成任务，研究了第二语言习得年龄的神经相关性。早期双语者优先募集参与运动控制和发音的左半球感觉运动区域。相比之下，后期学习者在更大程度上动用了参与执行性认知控制和词汇提取的区域。这些数据支持这样一种观点，即早期第二语言学习者在词汇检索过程中将神经资源用于运动控制。相反，后期第二语言学习者调用执行控制机制来生成过去时态。这些数据与双语语言学习的S/E模型一致，并作为认知控制理论的延伸。