We present an artificial lexicon study designed to test the hypothesis that native English speakers experience interference from written input when acquiring surface voicing in German words. Native English speakers were exposed to German-like words (e.g., /？tɑit/ and /？tɑid/, both pronounced [？tɑit]) along with pictured meanings, and in some cases, their written forms (e.g., and ). At test, participants whose input included the written forms were more likely to produce final voiced obstruents when naming the pictures, indicating that access to the written forms in the input interfered with their acquisition of target-like surface forms. In a separate experiment, we attempted to moderate this negative impact of the written input by explicitly telling participants about the misleading nature of the words’ written forms, with no beneficial effect on their pronunciation accuracy. Together these findings indicate a powerful influence of orthographic input on second language lexical–phonological development that is not readily overcome by a simple intervention
