ABSTRACT
This chapter reviews research on OEs on L+ phonology, a topic that has received much attention in the past decade. After a short historical background, it shows how orthographic forms facilitate the acquisition of L+ sounds and words. Then, it presents and discusses evidence of negative effects: Orthography-induced sound additions, omissions, and substitutions. The last category is the most frequently reported, and it is often caused by an incongruence between the grapheme-phoneme correspondences of the L1 and the L+. It is then argued that OEs are ultimately caused by inconsistencies between the L+ orthographic knowledge of L+ learners and users and how the L+ writing system actually works, resulting in unattested grapheme-phoneme correspondences (GPCs). To offer a balanced view, the next section reviews studies that reported no OEs and discusses possible reasons for such null effects. Finally, the chapter reviews what is known about variables that may modulate OEs, concluding that there is not enough evidence.
