Morphological processing in adults and children during visual word recognition

The research presented in this thesis examines cognitive processes involved in the recognition of written morphologically complex words in skilled readers and the acquisition of these mechanisms in developing readers. All experiments focus on non-strategic aspects of rapid morphological segmentation, exploring the nature of underlying lower-level orthographic processing constraints in morphological decomposition. The influences of orthographic processing constraints upon morphological processing are explored by distinguishing between lower-level morpho-orthographic and higher-lever morpho-semantic processing mechanisms. The introductory thesis chapter reviews evidence of different forms of purely structural non-semantic morphological processes and discusses the implication for morphological processing theories as well as orthographic processing theories. The role of morphological decomposition in visual word recognition is then examined across four different chapters (testing 446 adult participants and 72 children), in both English and Spanish native speakers. To explore non-conscious stages of cognitive processing, the present research draws upon the masked priming paradigm, providing a window into early, automatic processes in visual word recognition. In Chapters 2, 3, and 4, a novel approach is used combining the masked priming paradigm with the transposed-letter priming paradigm to examine if and how the encoding of morphological information is modulated by lower-level letter position processing mechanisms, in skilled readers. The final chapter provides a summary of the presented findings across all chapters and gives an outlook on future research prospects. We conclude that morphological processing in both skilled and developing readers is based on both morphoorthographic and morpho-semantic processing mechanism, which we discuss in the context of current morphological processing theories.