Syntactic processing of Mandarin Chinese as a second language recruits a crucial frontoparietal network

Previous L1 syntactic processing studies have identified the crucial left frontotemporal network, whereas research on L2 syntactic processing has shown that learner factors, such as L2 proficiency and linguistic distance, can modulate the related networks. Here, we developed a function-word-based jabberwocky sentence reading paradigm to investigate the neural correlates underlying Chinese L2 syntactic processing. Twenty Chinese L2 Korean native speakers were recruited in this fMRI study. Chinese proficiency test scores and Chinese-Korean syntactic similarity scores were measured to quantify the learner factors, respectively. The imaging results revealed an effective left frontoparietal network involving superior parietal lobule (SPL), posterior inferior frontal gyrus (pIFG) and precentral gyrus (PreCG). Moreover, the signal intensity of SPL as well as the connectivity strength between SPL and PreCG significantly correlated with the learner factors. These findings shed light on the neurobiological relationships between L1 and L2 syntactic processing and on the modulation of L2 learner factors.