The Effects of Semantic and Syntactic Factors on Complex Word Processing

The studies in this thesis examine the semantic and syntactic factors that influence the recognition of morphologically complex words. The experiments of Chapter 2 explored the competing mechanisms between stem homographs. Unmasked priming experiments showed that the presence of inhibitory priming between complex words that correspond to different meanings of a homograph is dependent on the relative dominance of the prime-target pair. That is, inhibitory priming was found when the prime corresponded to the dominant meaning of the homograph and the target to the subordinate meaning (e.g., fined as a prime for FINEST), but not when the relative dominance was reversed (e.g., longer-LONGING). Within a masked priming paradigm, the incompatible condition with dominant primes and subordinate targets did not produce facilitatory priming, while facilitatory priming was found when relative dominance was reversed. Chapter 3 examined the effects of semantic transparency on unmasked morphological priming and base frequency effects, and found that the size of the morphological priming and base frequency effects interacted with semantic transparency in a continuous manner. Specifically, complex words that were higher on transparency (e.g., thriller) produced larger priming and base frequency effects than partially transparent words that were low on transparency (e.g., archer), while words with no semantic overlap with their stems (e.g., corner) did not produce any significant results. The experiments reported in Chapter 4 looked at nonword processing. The processing of nonwords with derivational suffixes was based on the interpretability of the stem and affix, where the more interpretable combinations (e.g., STRENGTHIFY) were harder to identify as nonwords than the less interpretable ones (e.g., OAKABLE). For the nonwords with inflectional suffixes, those with grammatically incompatible stem-affix combinations (e.g., GIANTED) were easier to reject as words compared to the semantically incompatible (e.g., OXYGENS), and interpretable nonwords (e.g., GOOSES), which suggests that the processing of nonwords with inflectional suffixes was based on the type of incompatibility between the stem and affix. The implications of these results for existing models of complex word processing were discussed, including connectionist frameworks, the supralexical model, and pre-lexical decomposition models