Morphological Complexity and Lexical Processing Costs

Abstract

Although many words are formed by more than one morphological constituent, not all of them are complex words. In the framework of morphological analysis, the term ‘complex word’ usually sets apart words formed by a root, a stem index and inflectional affixes, from words formed by derivation, modification or compounding. This distinction is quite simplistic since all words display a certain degree of complexity. In the literature, there are abundant claims that morphological structure plays an important role in word processing, but the level of morphological complexity is never taken into account. In this paper, we will try to contribute to the discussion of the role of morphological structure for written word processing, namely by taking into consideration the level of morphological complexity of a particular set of Portuguese derived words. We will look at the results of a priming experiment involving a lexical decision task on three sets of derivatives in -oso: the first set is formed by compositional structures; in the second, we have included words that display an allomorph of the suffix (i.e. –oso ~ –uoso); and, in the third set, we gathered words that make use of an allomorphic base. The results of this experiment confirm that derived word processing is sensitive to the morphological structure of the word and they also show that compositional structures involve lower processing costs. Hence, these results allow us to claim that the degree of morphological complexity of complex words needs to be considered for the study of written word processing.