A quest for a unitary explanation of the object disadvantage in incremental processing: evidence from a modified maze task with Italian relative clauses

Abstract This study investigates incremental processing of subject and object relatives in Italian by comparing two experimental paradigms. Previous research has shown that object relatives are more difficult to process than subject relatives, but the source and timing of this object disadvantage remain debated. Two experiments were conducted using the same linguistic stimuli. Experiment 1 employed a novel mixed design: a lexical maze task for the relative clause combined with a self-paced reading task for the matrix clause. Experiment 2 used a self-paced reading paradigm. Results confirmed a disadvantage for object relatives across both tasks. Critically, the modified maze task revealed that this difficulty emerges immediately after the complementizer and persists in later regions, a finding that was not evident in the self-paced reading task or in previous maze task studies. This shows the greater temporal resolution of the maze paradigm for identifying the locus of syntactic difficulty in incremental processing. Although frequency-based surprisal and memory-based integration accounts explain portions of data, we consider two approaches that can offer a unified account for both early and late effects: an extension of featural relativized minimality and the cue-based retrieval account. We conclude by indicating how future research can disentangle the two accounts.