A Content - addressable Pointer Mechanism Underlies Comprehension

Ellipsis Interpreting a verb-phrase ellipsis (VP ellipsis) requires accessing an antecedent in memory, and then integrating a representation of this antecedent into the local context. This problem was investigated in 4 speed-accuracy trade-off and 2 eye-tracking experiments. To investigate whether the antecedent for a VP ellipsis is accessed with a search or direct-access retrieval process, Experiments 1 and 2 measured the affect of the distance between an ellipsis and its antecedent on the speed and accuracy of comprehension. Accuracy was lower with longer distances, indicating that interpolated material reduced the quality of retrieved information about the antecedent. However, contra a search process, distance did not affect the speed of interpreting ellipsis. This pattern suggests that antecedent representations are content-addressable and retrieved with a direct-access process. To determine whether interpreting ellipsis involves copying antecedent information into the ellipsis site, Experiments 3-6 manipulated the length and complexity of the antecedent. Some types of antecedent complexity—particularly, the number of discourse entities in the antecedent—lowered accuracy. However, neither antecedent length nor complexity affected the speed of interpreting the ellipsis. This pattern is inconsistent with a copy operation, and it suggests that ellipsis interpretation may involve a pointer to extant structures in memory. Ellipsis Natural language often contains dependencies that span several words, phrases, or even clauses. To interpret expressions with nonadjacent dependencies, language comprehenders must, at a minimum, identify the site of the dependency, access a representation of an earlier-processed constituent, and then integrate that constituent into the local structure. We report six experiments that investigate the processing of sentences with nonadjacent dependencies stemming from a verb-phrase ellipsis (VP ellipsis). The experiments were designed to test how a representation of the antecedent of the VP ellipsis is accessed at the elision site, and how it is then integrated into the local structure. our findings suggest that an antecedent of ellipsis is accessed with a content-addressable process, which enables the antecedent to be directly accessed without the need for a search through irrelevant memory representations. We also report findings that are inconsistent with claims that the retrieved antecedent is "copied" into the local structure. Rather, our results suggest that a pointer-like mechanism is used to interpret the VP ellipsis. This appears to be the case even when the antecedent contains a variable that must be reinterpreted at the ellipsis site. Verb-phrase ellipsis VP ellipsis is the omission of a verb phrase that is necessary for …