Hachmann, W. & Schroeder, S.
Max Planck Institute for Human Development Berlin, Germany
We investigated the time course of artificial written language acquisition in adults, in particular trying to assess the process of chunking letters into words. Participants learn to read medium frequent 5-7 letter German words written in newly assigned Thai letters over three sessions. Manipulating the sublexical level, the grapheme-phoneme correspondence (gpc) is altered such that in four language sounds, the letter coding is different from standard German. On the lexical level, we manipulated the frequency of occurrence. After training, participants fulfill a lexical decision task in the new script to track their newly acquired word level reading, and a pseudoword reading task to assess level of segmentation and transfer of sublexical (gpc) rules. According to the Psycholinguistic Grain Size Theory, the time course of acquisition should follow development from letter segmentation through interactions with chunking of sublexical units to fast automatized word reading.
Participants segment words into sublexical units without instruction. Different sublexical effects are visible during training and in the nonword reading transfer task. The lexical decision task, that incorporates a full frequency x length x gpc-change design, shows transfer effects of frequency, gpc-rules and word length on the lexical level as they develop across all three sessions.