a b s t r a c tThe current study investigates reading aloud words in Persian, a language that does not mark all its vowels in the script. Behaviorally, a masked onset priming effect (MOPE) was revealed for transparent words, with faster speech onset latencies in the phoneme-matching condition (i.e. phonological prime and target onset overlap; e.g. ﺱ ﺍ ﻝ /sɒːl/; 'year' -ﺹ ﻭ ﺕ /sot/; 'voice') than the phoneme-mismatching condition (e.g. ﺕ ﺍ ﺏ /tɒːb/ 'swing' -ﺹ ﻭ ﺕ /sot/; 'voice'). For opaque target words (e.g. ﺹ ﻝ ﺡ /solh/; 'peace'), no such effect was found. However, event-related potentials (ERPs) did reveal an amplitude difference between the two prime conditions in the 80-160 ms time window for transparent as well as opaque words. Only for the former, this effect continued into the 300-480 ms time window. This finding constrains the time course of the MOPE and suggests the simultaneous activation of both the non-lexical grapheme-to-phoneme and the lexical route in the dual-route cascaded (DRC) model.