Department of Psychiatric Neurophysiology, University Hospital of Psychiatry and Psychotherapy, University of Bern Bern, Switzerland ; Department of Clinical Psychology and Psychotherapy, Institute of Psychology, University of Bern Bern, Switzerland ; Center for Cognition, Learning and Memory, University of Bern Bern, Switzerland.
Department of Psychiatric Neurophysiology, University Hospital of Psychiatry and Psychotherapy, University of Bern Bern, Switzerland.
Front Psychol. 2014 Oct 2;5:1116. doi: 10.3389/fpsyg.2014.01116. eCollection 2014.
Within the field of neuroscientific research on second language learning, considerable attention has been devoted to functional and recently also structural changes related to second language acquisition. The present literature review summarizes studies that investigated structural changes related to bilingualism. Furthermore, as recent evidence has suggested that native-like exposure to a second language (i.e., a naturalistic learning setting or immersion) considerably impacts second language learning, all findings are reflected with respect to the learning environment. Aggregating the existing evidence, we conclude that structural changes in left inferior frontal and inferior parietal regions have been observed in studies on cortical gray matter changes, while the anterior parts of the corpus callosum have been repeatedly found to reflect bilingualism in studies on white matter (WM) connectivity. Regarding the learning environment, no cortical alterations can be attributed specifically to naturalistic or classroom learning. With regard to WM changes, one might tentatively propose that changes in IFOF and SLF are possibly more prominently observed in studies investigating bilinguals with a naturalistic learning experience. However, future studies are needed to replicate and strengthen the existing evidence and to directly test the impact of naturalistic exposure on structural brain plasticity.
在第二语言学习的神经科学研究领域，人们相当关注与第二语言习得相关的功能和最近的结构变化。本文献综述总结了调查与双语有关的结构变化的研究。此外，由于最近的证据表明，母语样的第二语言接触（即自然学习环境或沉浸式学习）对第二语言学习有很大的影响，因此所有的发现都反映了学习环境。综合现有证据，我们得出结论，在皮质灰质变化的研究中观察到左侧额下回和顶下小叶区域的结构变化，而在白质（WM）连接的研究中，胼胝体的前部则反复发现反映双语的情况。关于学习环境，不能将皮质的改变专门归因于自然或课堂学习。关于 WM 的变化，人们可以推测，在研究具有自然学习经验的双语者时，更可能观察到 IFOF 和 SLF 的变化。然而，需要进一步的研究来复制和加强现有证据，并直接测试自然暴露对结构大脑可塑性的影响。
