Zawiszewski, A. , Erdocia, K. , Santesteban, M. & Laka, I.
University of the Basque Country
Several ERP studies show that morphological violations elicit a late positivity (P600), often preceded by LAN or N400) (Coulson et al., 1998; Molinaro et al., 2008). Here we investigate in further detail the generality of the neurocognitive processes underlying morphological processing. To this end we compare case marking morphemes and postpositions, debated in Linguistics as to whether they belong to one or two distinct categories (Mahajan, 2008). We conducted an ERP experiment in Basque with three conditions: (i) ergative case (ERG), (ii) dative case (DAT) and (iii) postposition “to” (TO). Morphologically well-formed nouns (irakaslea-k 'teacher-ERG', neska-ri 'girl-DAT' and klase-ra 'classroom-TO') were compared to ungrammatical counterparts (irakaslea, neska and klasea), all of them lacking the case marker or postposition required by the sentence context. 23 native speakers participated in the study. ERPs were registered while participants read grammatical and ungrammatical sentences (word-by-word) and performed a grammaticality judgment task. Results showed significantly higher accuracy and faster response times to case than to postposition violations. All violations elicited a P600 component, but only case violations generated an N400. Our results suggest that there are fine-grained distinctions in morphological processing related to grammatical category, where case and postpositions are distinct.