Abstract
Stenning, Shepherd, and Levy (1988) showed that when simple texts switch reference predictably between individuals, changes of reference neither cost reading time nor degrade memory performance. The present experiments examine the effects of unpredictable referential change. Experiment 1 demonstrates that unpredictable reference change does cost processing time, as a function of the amount known about the referent to which attention shifts. Analysis reveals a distinction between primary and secondary individuals related to referential change. It also reveals word-length effects, both decelerations and accelerations proportional to description length, which are interpreted in terms of use of the articulatory loop (Baddeley, 1986). Experiment 1 reveals involvement of primary/secondary status in the process of switching reference and shows that the word-length effects cannot be interpreted in terms of frequency. Experiment 2 strengthens support for the primary/secondary distinction and confirms the use of the articulatory loop. The present results suggest a central role for distributed information about sequence in representing complex semantic structures both in immediate and in long-term memory. Predictable switching costs no time because the transparency of the relation between surface sequence and underlying semantic structure is preserved. The distinction between primary and secondary individuals emerges with unpredictable reference because it restores this transparency.