Short-term language experience shapes the plasticity of the visual word form area

Abstract

Previous studies have identified a region in the left fusiform gyrus that responds selectively to visual words, termed the visual word form area (VWFA). Converging evidence from neuropsychological, electrophysiological, and functional neuroimaging studies suggests that the VWFA is wired up largely by long-term experience because it responds specifically to words and letter strings only in an orthography a subject knows. However, it is less clear whether the plasticity of the VWFA can be modulated by short-term language experience. Here, we used functional magnetic resonance imaging (fMRI) to address this question by examining whether the representation for novel stimuli could be constructed in the VWFA after a short-term language experience. In particular, we trained subjects to associate a set of novel stimuli with English letters. We found that VWFA response to the trained stimuli was significantly higher than that of untrained stimuli after 3 days of association training. This learning-induced change in neural activities was absent in other specialized cortical areas involved in face perception or in processing object shapes. Multivariate pattern analysis further revealed that the learning-induced representation engaged the same neural population underlying the representation for language forms constructed through long-term experience. Our study clearly illuminates that the plasticity of the VWFA can be shaped by short-term language experience, bridging the gap between short-term and long-term experiences in language learning.