The role of semantics in the segmentation of morphologically complex words was examined using event-related potentials (ERPs) recorded to target words primed by semantically transparent (hunter-hunt,) opaque (corner-corn), and orthographically related (scandal-scan) masked primes. Behavioral data showed that only transparent items gave rise to priming. The ERP data showed both N250 and the N400 effects with transparent items generating greater priming than orthographic or opaque. Furthermore, priming effects across conditions revealed the existence of a significant linear trend, with transparent items showing the greatest effects and orthographic items the smallest, suggesting that these priming effects vary as a function of morphological structure and semantic transparency. The results are discussed in terms of a model of morphological processing.

The role of semantics in the segmentation of morphologically complex words was examined using event-related potentials (ERPs) recorded to target words primed by semantically transparent (hunterhunt,) opaque (corner-corn), and orthographically related (scandal-scan) masked primes. Behavioral data showed that only transparent items gave rise to priming. The ERP data showed both N250 and the N400 effects with transparent items generating greater priming than orthographic or opaque. Furthermore, priming effects across conditions revealed the existence of a significant linear trend, with transparent items showing the greatest effects and orthographic items the smallest, suggesting that these priming effects vary as a function of morphological structure and semantic transparency. The results are discussed in terms of a model of morphological processing. Descriptors ERP; N400; Masked priming; MorphologyPrior research on the processing of morphologically complex words has focused on identifying the extent to which morphological information is automatically retrieved during word processing. Most researchers agree that morphological information of some kind becomes available during the processing of a complex word. Nevertheless, there is still disagreement about how this information is stored in memory. Complex words may be stored as full forms in the mental lexicon or, alternatively, they may be represented as a combination of their constituent morphemes and undergo decomposition during processing.The degree to which morphologically complex words are semantically transparent may be important in determining to what extent such words undergo decomposition, as it seems intuitively plausible that lexical entries for semantically related words should be related in some way (Marslen-Wilson, Tyler, Waksler, & Older, 1994). If semantically related items share the lexical entry of their common stem, it is possible that lexical access is achieved via a representation of the stem rather than the derived form. A morphologically complex word is semantically transparent if its meaning can be derived directly from the combined meaning of its stem and affix (e.g., "un-happy"). In contrast, the meaning of semantically opaque words NIH Public Access Author ManuscriptPsychophysiology. Author manuscript; available in PMC 2009 September 24. Published in final edited form as:Psychophysiology. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript (e.g., "department") cannot be directly derived from the combined meaning of their component morphemes. Although at an earlier time in the history of the English language such words may have been related, and they may still be considered to have a morphological structure in that they consist of a clear stem and affix, the morphological relationship is formal rather than semantic.The present study aims to provide further empirical evidence with respect to the extent to which morphologically complex words are decomposed during processing, by using morphological priming and ...