Wh-question processing in Italian-speaking adults

The processing of Wh-questions in Italian-speaking adults has been investigated by De Vincenzi (1991a, 1991b, 1996) with the purpose of showing how the computation of Wh-questions can follow processing principles, whose validity can extend cross-linguistically. The author’s attention focuses on two asymmetries, i.e. the one between subject and object Wh-questions and the one between Who and WhichNP Wh-elements.

Once the two factors are combined, four different kinds of Wh-questions are obtained:

Who Subject questions, Who object questions, WhichNP subject questions and WhichNP object questions. In all experimental sentences, the post-verbal argument (either the object in subject Wh-Questions or the subject in object Wh-Questions) is realized as a full lexical DP. Data are collected by using a self-paced reading task. Results reveal the following general tendency: participants read Who-questions faster than WhichNP-questions and subject WhichNP-questions faster than object WhichNP-questions. Moreover, the two factors interact so that the shortest reading times correspond to Who subject questions. Therefore, the asymmetry between subject and object extraction is particularly evident in the case of Who questions. In order to interpret the data, De Vincenzi (1991b) primarily evaluates processing loads; in doing so, the researcher comes to the formulation of the Minimal Chain Principle (De Vincenzi, 1991b):

(50) Avoid postulating unnecessary chain members at S-structure, but do not delay required chain members. (De Vincenzi, 1991b:199)

The principle is composed of two constraints that correspond to economical guidelines to be followed during the computation, in order to create the simplest and most economic representation of the sentence at stake. The first part of the principle requires building only the exact amount of structure that is necessary to represent the encountered linguistic material, thus avoiding the postulation of any redundant element. It follows that the parser resorts to movement only when this is unavoidable and it prefers assuming singleton chains over multiple chains. The counterpart to this first economic guideline warns

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against procrastinating the insertion of chain members required in the structure. Holding up unassigned elements in the working memory entails a considerable burden; thus, the computation load can be significantly reduced by structuring the material. It follows that the parser should assign each element to a position in the structure as soon as this is possible. In the case of Who/What questions, the parser starts its computation by encountering an element that clearly signals that movement already took place. At this point, the parser discards the hypothesis of a singleton chain and assumes the existence of at least one other element in the chain (the position where the Wh-element was first merged and subsequently extracted). Afterwards, the parser constructs the simplest possible chain, namely the shortest in terms of distance and number of nodes: this corresponds to a chain entailing subject extraction. In other words, the parser assigns the filler (the Wh-element) the first possible gap in the structure, which happens to be the one corresponding to the subject position.

This strategy reminds of the Active Filler Hypothesis proposed by Frazier & Flores D’Arcais (1989), according to whom, parsing is filler-driven and not gap-driven. In other words, authors disregard the possibility that the parser starts the search for a filler only once an unexpected gap is found. Their proposal actually claims that the parser works exactly the other way around: as soon as an element is identified as a potential filler, the search for a corresponding gap starts. In the case of subject questions, the outcome is successful: the filler is immediately assigned to a gap and the parser can continue the computation with a reduced burden. The lack of unassigned elements in the working memory keeps processing loads low and the parser does not encounter any contra-evidence to its structure, thus completing the sentence processing quickly and accurately.

In the case of object questions, the structure contains evidence against the shortest possible chain. In particular, the appearance of a second element endowed with a subject syntactic role and an agent theta-role forces the parser to abandon the first analysis and proceed through a reparation. At that point, it is necessary to revise the all structure and to repair it in order to account for the syntactic evidence at hand. In the case of object questions, it derives that the Wh-element must be assigned to a new gap, namely to the one corresponding to the internal argument in the VP. According to De Vincenzi (1991b, 1996), the well-known asymmetry between subject and object extraction stems exactly from this parsing procedure based on economical guidelines which impose to start the

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derivation by assuming the simplest structure. In the case of subject extraction, the strategy is successful, while it is not in the case of object extraction. In the latter case, this translates into longer reading times: an experimental measure that reveals the necessity to revise and repair the sentence structure.

The discussed experiments take into account a second factor: the influence of the type of Wh-element in use, namely Who versus WhichNP questions. De Vincenzi bases her discussion on properties of Wh-elements that Cinque (1990) and Rizzi (1990) had previously pointed out in their works. In particular, the author is interested in the different kinds of chains that the two elements require and their consequences for the computation of Wh-questions. Wh-elements of the Who/What type are non-referential in nature and enter chains of the antecedent-government type. Thus, once the parser meets an element of this type, it immediately starts the search for the completion of the chain within the sentence. Moreover, according to Pesetsky (1987) the interpretation of such elements can start only once these fit into the argumental structure of the sentence predicate. In De Vincenzi’s view, this enhances the pressure for finding a suitable gap for the element as soon as possible. In conclusion, Wh-elements of the Who/What type prototypically fall under the Minimal Chain Principle described above.

In contrast, Wh-elements of the WhichNP type are referential in the sense that they have the capacity to refer to an element already present in the discourse. This property subtracts the elements from being subordinated to strict locality constraints and allows them to enter binding chains, similar to those applied in the relation between a pronoun and its preceding referent. Furthermore, the parser can start interpreting WhichNP operators as soon as one is met, precisely thanks to their referentiality. Due to the combination of these two characteristics, namely referentiality and presence of a binding chain, the Minimal Chain Principle (De Vincenzi, 1996:120) constrains the processing of WhichNP questions to a lower extent. Indeed, once a WhichNP element is met, the parser assumes that it is in a singleton chain and looks for an element this can be bound to. In particular, it looks for an anaphoric pronoun. If it does not encounter any, as in the case of Wh-questions, the WhichNP element must be integrated in the sentence derivation and assigned to an argument position (the gap). The procedure is more demanding in terms of time and resources if compared to the speed and accuracy with which Who subject questions are processed. On the other hand, though, the interpretation of WhichNP

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questions proceeds in a very cautious way, that avoids the assignment of incorrect gaps and therefore prevents the necessity to revise and repair the derivation along the way. In these terms, De Vincenzi (1996) accounts for the better performance of her speakers on Which subject and object questions in comparison to Who object questions.

Summing up, De Vincenzi’s (1991a, 1991b, 1996) analysis of how adult speakers process Wh-questions builds on processing procedures that, in turn, are determined by strict economic principles. The assumption of the Minimal Chain Principles also implies that processing asymmetries (like the one between subject and object extraction) are to be attributed not only to strictly syntactic reasons. In other words, syntax is not the primary cause of the observed patterns of Wh-questions comprehension. In her view, the primary cause of processing asymmetries is the application of economical principles to specific linguistic systems. Therefore, De Vincenzi stretches the limits of her analysis beyond Italian, and claims that the principle is universally valid across languages, although its manifestation can differ, depending on the syntactic structures in use. Not only does De Vincenzi consider the Principle universally valid for adults, but she also extends it to monolingual young children. The following section provides some insights into L1 acquisition.