Increased Gray Matter Volume Induced by Chinese Language Acquisition in Adult Alphabetic Language Speakers

Liu Tu; Fangyuan Zhou; Kei Omata; Wendi Li; Ruiwang Huang; Wei Gao; Zhenzhen Zhu; Yanyan Li; Chang Liu; Mengying Mao; Shuyu Zhang; Takashi Hanakawa

doi:10.3389/fpsyg.2022.824219

Increased Gray Matter Volume Induced by Chinese Language Acquisition in Adult Alphabetic Language Speakers

Front Psychol. 2022 Apr 25:13:824219. doi: 10.3389/fpsyg.2022.824219. eCollection 2022.

Authors

Liu Tu¹, Fangyuan Zhou¹, Kei Omata², Wendi Li¹, Ruiwang Huang³, Wei Gao¹, Zhenzhen Zhu⁴, Yanyan Li⁵, Chang Liu⁶, Mengying Mao¹, Shuyu Zhang¹, Takashi Hanakawa⁷

Affiliations

¹ College of Foreign Studies, Jinan University, Guangzhou, China.
² Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Kodaira, Japan.
³ School of Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong, Center for the Study of Applied Psychology and MRI Center, South China Normal University, Guangzhou, China.
⁴ Center for Linguistics and Applied Linguistics, Guangdong University of Foreign Studies, Guangzhou, China.
⁵ Higher Education Mega Center, Guangzhou, China.
⁶ South China Business Trade College, Guangzhou, China.
⁷ Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of Medicine, Kyoto, Japan.

Abstract

It is interesting to explore the effects of second language (L2) acquisition on anatomical change in brain at different stages for the neural structural adaptations are dynamic. Short-term Chinese training effects on brain anatomical structures in alphabetic language speakers have been already studied. However, little is known about the adaptations of the gray matter induced by acquiring Chinese language for a relatively long learning period in adult alphabetic language speakers. To explore this issue, we recruited 38 Indian overseas students in China as our subjects. The learned group included 17 participants who had learned Mandarin Chinese for an average of 3.24 years and achieved intermediate Chinese language proficiency. The control group included 21 subjects who had no knowledge about Chinese. None of the participants had any experience in learning logographic and tonal language before Chinese learning. We found that (1) the learned group had significantly greater gray matter volume (GMV) in the left lingual gyrus (LG) compared with the control group; (2) the Chinese characters' reading accuracy was significantly and positively correlated to the GMV in the left LG and fusiform gyrus (FG) across the two groups; and (3) in the learned group, the duration of Chinese learning was significantly and positively correlated with the GMV in the left inferior frontal gyrus (IFG) after correction for multiple comparisons with small volume corrections. Our structural imaging findings are in line with the functional imaging studies reporting increased brain activation induced by Chinese acquisition in alphabetic language speakers. The regional gray matter changes reflected the additional requirements imposed by the more difficult processing of Chinese characters and tones. The present study also show that the biological bases of the adaptations induced by a relatively long period of Chinese learning were limited in the common areas for first and foreign language processing.

Keywords: VBM; acquisition; gray matter; logographs; plasticity.