Processing Subject and Object Relative Clauses: Evidence from Eye Movements

Three eye-movement-monitoring experiments investigated processing of sentences containing subject-relative and object-relative clauses. The first experiment showed that sentences containing object-relative clauses were more difficult to process than sentences containing subject-relative clauses during the relative clause and the matrix verb. The second experiment manipulated the plausibility of the sentential subject and the noun within the relative clause as the agent of the action represented by the verb in the relative clause. Readers experienced greater difficulty during processing of sentences containing object-relative clauses than subject-relative clauses. The third experiment manipulated the animacy of the sentential subject and the noun within the relative clause. This experiment demonstrated that the difficulty associated with object-relative clauses was greatly reduced when the sentential subject was inanimate. We interpret the results with respect to theories of syntactic parsing.