Paradigmatic and extraparadigmatic morphology in the mental lexicon

The present study discusses psycholinguistic evidence for a difference between paradigmatic and extraparadigmatic morphology by investigating the processing of Finnish inflected and cliticized words. The data are derived from three sources of Finnish: from single-word reading performance in an agrammatic deep dyslectic speaker, as well as from visual lexical decision and wordness/learnability ratings of cliticized vs. inflected items by normal Finnish speakers. The agrammatic speaker showed awareness of the suffixes in multimorphemic words, including clitics, since he attempted to fill in this slot with morphological material. However, he never produced a clitic — either as the correct response or as an error — in any morphological configuration (simplex, derived, inflected, compound). Moreover, he produced more nominative singular errors for case-inflected nouns than he did for the cliticized words, a pattern that is expected if case-inflected forms were closely associated with their lexical heads, i.e., if they were paradigmatic and cliticized words were not. Furthermore, a visual lexical decision task with normal speakers of Finnish, showed an additional processing cost (longer latencies and more errors on cliticized than on case-inflected noun forms). Finally, a rating task indicated no difference in relative wordness between these two types of words. However, the same cliticized words were judged harder to learn as L2 items than the inflected words, most probably due to their conceptual/semantic properties, in other words due to their lack of word-level translation equivalents in SAVE languages. Taken together, the present results suggest that the distinction between paradigmatic and extraparadigmatic morphology is psychologically real.