Virtually Immersed in Language: a DTI Study on Rapid Neural Plasticity and Virtual Learning Environments in L2 acquisition

Abstract: Objective Second language learning continues to be a field of growing interest both in academia and everyday life. As such, a more comprehensive understanding of the best learning methods remains an important area of focus. This study aimed to investigate single-session vocabulary acquisition and neural underpinnings of language learning through Diffusion Tensor Imaging (DTI), in relation to immersive language learning contexts. Method A total of 46 native Swedish speakers were compared before and after learning Mandarin Chinese in three groups: Virtual reality learning group (VR), Video game learning group (VE) and Controls. Potential changes in white matter organization were assessed using fractional anisotropy (FA) and an immediate and delayed vocabulary test provided a link between neural changes and learning outcomes. Results A significant increase in FA was found for the learning groups together (VR+VE) compared to the control group (t(31) = 3.89, p < .001) in the posterior part of the corpus callosum, known as the splenium. However, comparison of the learning groups separately revealed no significant differences in FA scores between the gaming modalities. This finding was further reflected in the vocabulary assessment: immediate and delayed recall indicated no significant differences between the gaming conditions (F(1,30) = 3.58, p = 0.068). Conclusion These findings contribute to our understanding of the rapid neural reorganization underlying language learning. The results highlight the effect of language learning on white matter plasticity but do not support more immersive 3D virtual reality outperforming a traditional 2D game environment in this learning method.