Individual differences in sentence processing: Effects of verbal working memory and cumulative linguistic knowledge
The present study investigates individual differences in sentence processing. The Verbal Working Memory (VWM) model and the Two Factor Model, involving VWM and Cumulative Linguistic Knowledge (CLK), are compared in three self-paced reading experiments, in which ditransitive sentences containing high/low-frequency words (Exp. 1) and canonical/scrambled transitive verb sentences (Exp. 2, Exp. 3) are presented. Results favor the Two Factor model over the VWM model: The contributions of VWM and CLK to sentence processing are independent of each other. Two types of demands on VWM, temporal syntactic ambiguity and filler-gap dependency, are mediated by readers’ VWM capacity in scrambled sentences. CLK mediates lexical frequency effect and structural frequency effect on reading time and comprehension accuracy. We also find an interaction between VWM capacity and CLK in distant scrambling sentences, which suggests that CLK and VWM share the same cognitive resource.
