Processing of temporary syntactic ambiguity in Italian "who"-questions: a study with event-related potentials

This study investigated the processing of direct Italian "who"-questions, containing a temporary ambiguity of the syntactic role (subject/object) of the initial pronoun. To this aim we measured event-related potentials (ERPs) evoked by the disambiguating verbal agreement word and by the following ones. Results showed two positive deflections, corresponding to a P300 and to a P600, only at the target verb of the object-first extraction, the condition which has been demonstrated to be less preferred by speakers. The functional meaning of this positive complex, similar to patterns already reported for German subject/object ambiguous relative clauses, was discussed with reference both to results obtained in other languages using similar sentences and to psycholinguistic parsing models.