Strategic Resources Support the Interpretation of Doubly-Quantified Sentences

Strategic Resources Support the Interpretation of Doubly-Quantified Sentences Corey T. McMillan (mcmillac@mail.med.upenn.edu) Neville Ryant (nryant@babel.ling.upenn.edu) Danielle Coleman (daco@sas.upenn.edu Robin Clark (rclark@babel.ling.upenn.edu) Murray Grossman (mgrossma@mail.med.upenn.edu) University of Pennsylvania, 3400 Spruce Street, 3 West Gates Philadelpha, PA 19104 USA Abstract Quantifiers like “all” and “every” are frequent in daily language. However, when a sentence contains two quantifiers or is “doubly-quantified” (e.g., “Every boy ate a cookie”) the meaning can often be ambiguous since there are two potential interpretations: collective (e.g., several boys sharing a single cookie) and distributive (e.g., several boys each eating their own cookie). Psycholinguistic studies have established empirical evidence for conflict between interpretations of a doubly-quantified sentence and have proposed that the interpretation of these sentences is “underspecified”. However, little is known about the the neural mechanisms that support the interpretation of doubly-quantified sentences. In an fMRI experiment we demonstrate that conflict between possible interpretations of doubly-quantified sentences is supported by brain regions situated in fronto-parietal cortex. We propose that an “underspecified” account is insufficient to account for our neuroanatomical results and instead argue that strategic decision-making resources may support the interpretation of doubly-quantified sentences. Keywords: Quantifiers; Semantics; Language Processing; Decision-Making; fMRI Introduction Quantifiers like “all” and “every” are extraordinarily frequent in daily language. The meaning of these quantifiers is well known. However, when these words are used in a doubly- quantified sentence the meaning can often be ambiguous. Consider for example, the following doubly-quantified sentences containing the quantifier “all”: (1) a. All the men built a stadium. b. All the men ate a cookie. The quantifier “all” prefers a collective interpretation such as in 1(a) when there is a set of men and they worked together to build a single stadium. However, in 1(b) a conflict arises between the preferred collective interpretation and the unlikely possibility that a set of men collectively eat a single cookie. The quantifier “every” also has a preferred interpretation, but it is distributive. For example, 2(b) is consistent with the preferred interpretation – a set of men and each man ate a different cookie. However, in 2(a) a conflict arises due to the preferred distributive interpretation and unlikely event of several men each building a unique stadium. (2) a. Every man built a stadium. b. Every man ate a cookie. Together, the examples in (1) and (2) illustrate that a conflict arises when individuals read doubly-quantified sentences with a preferred interpretation and this interpretation is unlikely. Empirical evidence for quantifier interpretation conflict has been well established within the psycholinguistic literature (Kurtzman & MacDonald, 1993; Filik et al., 2004; Paterson et al., 2008) . In a seminal reading experiment Kurtzman and MacDonald (1993) presented readers with doubly-quantified sentences like “Every boy climbed a tree” followed by a continuation sentence with either a collective interpretation (e.g., “The tree was full of apples”) or a distributive interpretation (e.g., “The trees were full of apples”) and asked readers to make a plausibility judgement. Participants were more likely to accept, and therefore preferred, the distributive interpretation rather than the collective interpretation. However, the preference for a distributive interpretation was diminished when doubly-quantified sentences were in a passive voice (e.g., The tree was climbed by every kid) or in a more complex noun phrase (e.g., George has every photograph of an admiral). This prompted Kurtzman and MacDonald (1993) to tentatively endorse a parallel parsing model that simultaneously incorporates several principles for resolving quantifier ambiguity and when a principle is not available readers randomly choose between a distributive and collective interpretation. In an eye-tracking experiment, Filik et al. (2004) demonstrated that reading times for doubly-quantified sentences containing “every” were longer for sentences with a less preferred collective continuation compared to a more preferred distributive continuation. This suggests there is a processing cost when readers encounter a less preferred interpretation and is consistent with Kurtzman and MacDonald (1993) parallel processing account (see also Paterson et al. (2008)). More recently, in an event related potential (ERP) experiment Dwivedi et al. (2010) presented individuals with doubly-quantified sentences and continuation sentences similar to Kurtzman and MacDonald (1993) and these were compared relative to matched unambiguous baselines (Every