«Structural priming to study scopal representations and operations Emmanuel Chemla (LSCP, CNRS) and Lewis Bott (Cardiff University) Squib to appear in ...»
Structural priming to study scopal representations and operations
Emmanuel Chemla (LSCP, CNRS) and Lewis Bott (Cardiff University)
Squib to appear in Linguistic Inquiry
Sentences can be ambiguous with respect to which expressions “take scope” over
others. For example, Every student read a book can be understood as meaning that all
students read a (possibly different) book or that there is a single book read by all
students. Previous work by Raffray and Pickering (2010) has shown that if people are exposed to one of the two interpretations, they can be primed to interpret subsequent scopally ambiguous sentences with that same interpretation. This could be seen as evidence for a Logical Form representation capturing scopal properties or as evidence for a scope reversal operation, whose application could be facilitated by a previous application (c.f. Quantifier Raising). We discuss the usefulness of such simple priming studies in linguistics. Based on the scope ambiguity example, we show that priming of representation and priming of operation can be distinguished. In an experiment testing the relevant predictions for our test case, we obtain that (1) priming is based not on operations but on representations, but (2) the relevant level of representation encodes only scopal relations between specific quantified expressions.
1. Introduction: representations and priming, the case of scopal relations
1.1. Scopal relations and representations Sentence (1) contains a universal quantifier every and an indefinite, existential quantifier a. Depending on which of these two elements takes scope over the other, we obtain two possible interpretations, as paraphrased unambiguously in (2).
(1) Every student read a book.
(2) a. Universal-wide scope interpretation:
For every student s, there is a book b(s) that s read.
b. Universal-narrow scope interpretation:
There is a book b, such that every student read b.
The universal interpretation in (2)a is surface scope: the scopal relation between the universal quantifier every and the existential quantifier a matches the order and hierarchy in which they appear in (1). The interpretation in (2)b is reverse scope: the scopal relation is reversed between the sentence and the interpretive level.
Our point of departure is an interesting finding by Raffray and Pickering (2010), who demonstrated that people can be primed to derive particular scopal interpretations (see details below). In this paper we emphasize that such priming results are useful to either characterize realistic layers of linguistic representations or to confirm the existence of linguistic operations of certain kinds. We do so by discussing two possible interpretations of Raffray and Pickering’s results and testing between them in an experiment.
1.2. Layers of representations and priming Raffray and Pickering’s (2010) study involved a structural priming paradigm (e.g., Bock, 1986; Branigan, Pickering & McLean, 2005; Pickering & Branigan, 1998;
Thothathiri & Snedeker, 2008; for a review see Pickering & Ferreira, 2008).
Participants completed a sentence-picture verification task that involved matching one of two pictures to a scopally ambiguous sentence, such as (1). There were prime trials 1 and probe trials. In prime trials, participants were forced to interpret the sentence with universal wide-scope (or universal narrow-scope) by the nature of the target picture, which contained a wide-scope image (or a narrow-scope image), and the foil picture, which contained an image that was inconsistent with the sentence. In the probe trials, which immediately followed prime trials, one of the pictures corresponded to the universal wide-scope interpretation of the sentence and the other to the universal narrow-scope interpretation. Participants were therefore “free” to choose either interpretation in the probe trials. Across two experiments, Raffray and Pickering found that participants were more likely to select the picture matching the wide-scope interpretation following a wide-scope prime trial than after a narrow-scope prime trial.
In other words, participants were primed to derive sentence interpretations with particular scopal relations. From these results they concluded that participants formed disambiguated
representations that specify quantifier-scope relations.
Concretely, the claim is that there exists a level of representation which looks like
the following semi-abstract patterns for the two possible interpretations of (1):
(3) Representations underlying the two interpretations:
a. Universal-wide representation: Every … is such that there is a… b. Universal-narrow representation: There is a … such that for every … These representations abstract away from some information, e.g., the content of the lexical material filling in the … parts. If these representations exist, we can understand why the activation of one of these patterns for a given sentence (the prime) can strengthen the activation of the same pattern for a subsequent sentence.
1.3. Linguistic operations and priming Priming effects can reveal a level of representation at which prime and probe are made equivalent, as discussed above. But they can also be evidence for the existence of some operation that applies equally to the prime and probe. In our concrete case, there might be an operation that transforms an interpretation of the (a) type, into an interpretation of the (b) type. This operation would correspond to a scope reversing operation, call it OSR. (An alternative plausible candidate for such an operation when indefinites are involved would be a domain narrowing operation, we come back to this in the discussion section). Such OSR operations would traditionally fall under the label of “movement” operations in the syntactic literature (e.g., Quantifier Raising, see e.g., Fox 2000). Formal and experimental results argue for the existence of such operations. For instance, developmental inquiries show that children under a certain age mostly access surface scope interpretations for a variety of configurations and only later the whole set of their corresponding reverse scope interpretations. This suggests that scope reversal is indeed a single piece in the system, a coherent operation that kids do not use early on but then, in one step, they master it across the board (see, e.g., Conroy, Lidz & Musolino 2009 for more detailed discussion).
In terms of this OSR operation, the (a) interpretation would follow from a representation at which hierarchical order and linear order have been aligned. The OSR operation could apply to this representation and reverse the scopal relations. In representational terms, we obtain: (b) = OSR(a).
We can now describe an alternative interpretation of the priming effects we discussed, as evidence for this OSR operation. Indeed, if the application OSR has been
1.4. Distinguishing representations and operations We will provide new evidence in favor of the linguistic layer interpretation, which was Raffray and Pickering’s (2010) original interpretation of their data and which may not be the most naturally available from a linguistic standpoint. Our strategy will be to study priming effects between sentences of different profiles. Specifically, we will study sentences such as (4).
(4) A student read every book.
(in our experiment: “There is a star above every heart”, see discussion below) (5) a. Universal-wide scope interpretation:
For every book b, there is a student s(b) that read b.
b. Universal-narrow scope interpretation:
There is a student s, such that every book was read by s.
Such sentences have the same two types of interpretations as our original example (1), the universal-wide interpretation and the universal-narrow interpretation. Crucially, however, the order of the quantifiers are reversed in the sentence: the indefinite a now occurs before the universal quantifier every. Hence, the two interpretations are obtained differently in (1) and (4) in terms of the OSR operation. Specifically, the OSR operation is involved to obtain the existential interpretation in the case of (1) and the universal interpretation in the case of (4). Hence, the surface scope interpretation of one sentence is the reverse scope interpretation of the other.
If the interpretation account is correct, then we should find priming of interpretation across sentence of types (1) and (4): the universal interpretation of one should prime the universal interpretation of the other. If the operation account is correct, then we should find the opposite type of priming across these sentence types, such that the surface scope of one primes the surface scope of the other, i.e. a universal-wide interpretation of one sentence primes a universal-narrow interpretation of the other.1
1.5. Extension of the prediction The operation interpretation based on OSR makes broader predictions. First, priming may occur across sentences using completely different pairs of quantifiers: sentences of the form Q1 V Q2 and Q3 V Q4 (where Q1, Q2, Q3 and Q4 are quantified DPs involving four different quantifiers) could prime each other’s surface and reverse interpretations, even though their impoverished representations as in (3) have nothing relevant in common. Second, radically different types of sentences require scope resolutions which may involve the OSR operation. For instance, negation may interact with a quantifier in roughly the same way in which two quantifiers (every and a) may We note that Raffray and Pickering (2010) tested whether sentences like (4) primed sentences like (1) (Experiment 3), just as we present in this paper. They reported that there was no significant priming effect, and that across experiments, priming was significantly greater within sentences like (1) than between sentences like (1) and (4). They further argued that this provided evidence against a straightforward representational account such as that which we suggest above. To foreshadow our findings, we find significant priming effects involving sentences like (4), in contrast to Raffray & Pickering, Experiment 3. We discuss the difference further in the General Discussion.
2. Experiment Our experiment tests whether scopal priming occurs because a representation is primed or because an operation is primed. Participants completed a sentence-picture verification task, similar to Raffray and Pickering (2010). Each trial consisted of a sentence and two pictures, and participants clicked on the picture that best matched the meaning of the sentence. The experimental trials all involved scopally ambiguous sentences. There were prime trials, in which the pictures dictated that only one meaning was acceptable, and probe trials, in which either meaning was acceptable (see Figure 1). Following Raffray and Pickering, we expected that the (forced) meaning of the sentence in the prime trials would influence the (free) meaning of the sentence in the probe trials. Sentences could either share the same abstract interpretation (e.g., universal-wide scope) across trials, or the presence of the OSR operation (e.g., reverse scope). Of interest was whether scope operation or interpretation would predict priming direction.
We used three types of configurations (sentences): Universal-Existential (U-E), as in (1); Existential-Universal (E-U), as in (4); and Universal-Negation (U-neg), as in (6). Each configuration could result in two interpretations: the universal-wide (Uwide) interpretation, as described in the a) examples of (2), (5) and (7), or as universal-narrow (U-narrow), as in the corresponding b) examples (see the Interpretation column of Table 1). The interpretations could also be classified with respect to the direction of the scopal relation, surface scope or reverse scope; but, crucially, the mapping between interpretation and the presence of a scope operation needed to obtain reverse scope varied across sentences (see the Operation column in Table 1). The dissociation between interpretation and operation meant that the priming accounts could be differentiated.
Priming was tested between all configurations. Thus, there were withinconfiguration trials, in which prime-probe pairs used the same configuration (e.g., EU primes followed by E-U probes), and between-configuration trials, in which primeprobe pairs used different configurations (e.g., E-U primes followed by U-Neg probes). For within-configuration trials, the interpretation and operation accounts make the same predictions. For between-configuration U-E/E-U trials, however, the If the scopal operation at stake with negation is different than the one for quantifiers, we also expect no priming for these sentences.
Table 1. Experimental sentences with the correspondence between interpretation and operation oriented descriptions The Interpretation column lists interpretations of each configuration and the Operation column describes the relation of this interpretation with the linear order of the words in the sentence, an operation being needed in reverse scope configurations.
Note that the U-wide and U-narrow interpretations are different for U-neg sentences than for the two-quantifier configurations. This is because the universal quantifier interacts with negation and not with an existential quantifier, as it does for U-E and E-U configurations.
2.1. Participants Eighty participants were recruited online using Amazon Turk. Two participants were removed because their native language was not English, and a further five were removed because their accuracy on the prime sentences was less than 90%.
2.2. Materials Sentences. Experimental sentences were constructed according to one of three frames.
- For U-E sentences: Every [Shape 1] is [above/below] a [Shape 2]
- For E-U sentences: There is a [Shape 1] [above/below] every [Shape 2]