Processing temporary syntactic ambiguity: The effect of contextual bias

Abstract

This paper reports two experiments using sentences with a temporary ambiguity between a direct object and a sentence complement analysis that is resolved toward the normally preferred direct object analysis. Postverbal noun phrases in these sentences could be ambiguously attached as either a direct object or the subject of a sentence complement, whereas in unambiguous versions of the sentences the subcategorization of the verb forced the direct object interpretation. Participants read these sentences in relatively long paragraph contexts, where the context supported the direct object analysis (“preferred”), supported the sentence complement analysis (“unpreferred”), or provided conflicting evidence about both analyses (“conflicting”). Self-paced reading times for ambiguous postverbal noun phrases were almost equivalent to the reading times of their unambiguous counterparts, even in unpreferred and conflicted context conditions. However, time to read a following region, which forced the direct object interpretation, was affected by the interaction of verb subcategorization ambiguity and contextual support. The full pattern of results do not fit well with either an unelaborated single-analysis (“garden path”) model or a competitive constraint-satisfaction model, but are consistent with a race model in which multiple factors affect the speed of constructing a single initial analysis.

Keywords:

• Syntactic ambiguity
• Context
• Ambiguous region

Acknowledgments

This research was reported as a part of a Master's thesis submitted by Mohamed Taha Mohamed to the University of Massachusetts. It was supported in part by Grant HD18708 from the National Institute of Child Health and Human Development (NICHD) to the University of Massachusetts. The contents of this paper are solely the responsibility of the authors and do not necessarily represent the official views of NICHD or the National Institutes of Health (NIH). We thank Adrian Staub for his comments on earlier versions of this manuscript, especially for advocating the race model that we present.

Notes

¹ The “constraint satisfaction” position has earlier roots in Tyler and Marslen-Wilson (1977) and in the “detective model” advanced by Clark and Clark (1977) and J. A. Fodor, Bever, and Garrett (1974).

² The ambiguity manipulation in this experiment compares unambiguous direct object verbs with verbs that ambiguously take a direct object or a sentence complement. There is a substantial literature about the effects of relative frequency of direct object versus sentence complement use of ambiguous verbs, but the literature is somewhat unclear about such effects. Some studies examine whether relative frequency of usage affects the size of any garden-path effects observed (Ferreira & Henderson, 1990; Kennison, 2001; Trueswell et al., 1993; Wilson & Garnsey, 2009), and others examine the interaction of relative frequency and plausibility (Garnsey et al., 1997; Pickering et al., 2000). Perhaps the safest conclusion to draw from these studies is that large biases toward one analysis or the other do not always block the simpler direct object analysis, but that evidence for the direct object analysis being entertained and evaluated for plausibility is most reliably obtained when the direct object and sentence complement analyses are roughly equally frequent, as they are in our materials.