Evidence for Early Morphological Decomposition: Combining Masked Priming with

■ Are words stored as morphologically structured representa-tions? If so, when during word recognition are morphological pieces accessed? Recent masked priming studies support mod-els that assume early decomposition of (potentially) morpholo-gically complex words. The electrophysiological evidence, however, is inconsistent. We combined masked morphological priming with magneto-encephalography (MEG), a technique particularly adept at indexing processes involved in lexical ac-cess. The latency of an MEG component peaking, on average, 220 msec post-onset of the target in left occipito-temporal brain regions was found to be sensitive to the morphological prime– target relationship under masked priming conditions in a visual lexical decision task. Shorter latencies for related than unrelated conditions were observed both for semantically transparent (cleaner–CLEAN) and opaque (corner–CORN) prime–target pairs, but not for prime–target pairs with only an orthographic relationship (brothel–BROTH). These effects are likely to re-flect a prelexical level of processing where form-based repre-sentations of stems and affixes are represented and are in contrast to models positing no morphological structure in lex-ical representations. Moreover, we present data regarding the transitional probability from stem to affix in a post hoc compar-ison, which suggests that this factor may modulate early mor-phological decomposition, particularly for opaque words. The timing of a robust MEG component sensitive to the morpholog-ical relatedness of prime–target pairs can be used to further understand the neural substrates and the time course of lexical processing.