Multilingualism is a modern phenomenon that is gaining more and more importance in our globalized world. An increasing number of studies have shown that multilingualism leads not only to cognitive advantages compared to monolingualism, but also changes the brain on a functional and structural level, underlying behavioural learning and performance. Structural changes have been observed in previous studies and have generally implied an increase in grey matter (GM) volume, GM density or white matter (WM) integrity for multilinguals compared to monolinguals. Previous studies are inconsistent in terms of the different factors examined and the obtained measurements and findings. The present study thus aimed at further investigating the structural correlates of multilingualism using nonparametric voxel-based morphometry (VBM) and a surface-based analysis in FreeSurfer...