Procedimientos y técnica .1 Obtención de las soluciones: (59)

Building a syntactic structure for incoming material and a representation of a sentence is assumed to happen instantaneously. With unambiguous sentences, this is comparatively straightforward, with ambiguous sentences less so. Ambiguity means that there are two options available for the parser to build so the parser will only select one of the two. There are two types of structural ambiguity; global and local. Globally ambiguous sentences are not resolved by the end of the sentence as in (6);

(6) Visiting relatives can be a nuisance

It is unclear in (6) whether the noun “relatives” is the object of the verb visiting or the subject of the verb be. The sentence does not provide any clues as to which reading is the correct one.

In sentences like (6), the interpretation the parser selects is one of the two interpretations. As the sentence is not disambiguated, the interpretation of the sentence is unlikely to be revised. But not all ambiguous sentences are like (6). Locally structurally ambiguous sentences are ambiguous only up until a point at which the content disambiguates between the two possible interpretations. In this case, only one interpretation is ultimately viable.

Garden-path sentences are a particular type of sentence with local structural ambiguity where the parser is misguided towards an erroneous initial interpretation of the sentence. An example of a garden-path sentence is (7) or (8)

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(7) He put the frog on the napkin on the table.

(8) While Mary dressed the baby slept.

Until a point (7) and (8) have two potential interpretations yet after the disambiguating material one of the two becomes unavailable.

The difficulty with (7) is that the parser will build a syntactic structure for the sentence but at the point of the second PP, the sentence becomes unambiguous and one of the two interpretations becomes unavailable. In the case of “He put the frog on the napkin on the

table”, speakers may consider the first PP to be a modifier of the verb and interpret it as the

destination (e.g. Trueswell et al. 1999). However, after the second PP, this becomes unviable and the first PP can only be interpreted as a modifier of the noun frog2. If the parser has already built a syntactic representation inconsistent with the ultimately correct reading of the sentence, this needs to be revised and a new one built after the parser has become aware of the need to do so. Similarly in (8), the parser is guided towards interpreting the NP “the baby” as the object of the verb “dressed”; it is only after the second verb “slept” that one realises that the NP has been misinterpreted and that it is the subject of the second verb (e.g. Trueswell et al. 1999). There is considerable research into whether children can do this in the same way as adults (see Chapter 4 for a more detailed review) but whether or not bilingual children can do so remains an empirical question.

Garden-path sentences have traditionally been used to test models of language processing. Structure-based accounts (Frazier, 1987a) posit that initial decisions regarding syntactic

2 _{Technically, in the aforementioned example, the first PP can still be interpreted as the}

destination with the second PP being interpreted as a modifier of the first PP (i.e. Put the frog on the napkin that is on the table). This possibility is not discussed in the original studies on garden-path effects (e.g. Trueswell et al., 1999) potentially because the visual stimuli would not support such an interpretation, as they wouldn’t in the studies on garden-path sentences in this thesis.

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structure formation are exclusively driven by the reader’s knowledge of the syntactic structures and possible constituents. The semantics of the verb or the distributional properties are not initially relevant in this type of account. Two parsing strategies have been postulated to guide the parser; minimal attachment and late closure. Minimal attachment (Frazier, 1987a, 1987b; Frazier & Rayner, 1982) is a tendency for the parser to attach incoming material parsimoniously in order to create the simplest syntactic structure possible. Therefore, in a sentence such as (9)

(9) The judge believed the defendant …. and threw out the charges / was lying”

(example from Osterhout, Hollcomb & Swinney, 1994:786), although both the option of a direct object to the verb and an embedded clause are possible, the human parser will most likely adopt the first interpretation because a sentence with an embedded clause would be structurally more complex and therefore, avoided until it was clear this was the appropriate syntactic representation of the sentence. It is under minimal attachment that the PP “on the

table” in (7) will be interpreted as the adjunct to the verb put rather than a complement to the

noun frog. For (8), the parser will attach the NP “the baby” as the object of “dressed” in order not to create an embedded clause and therefore, keep the sentence as simple as possible. The second parsing strategy is late closure (Frazier & Fodor, 1978). Under late closure, incoming material is assumed to be attached to the local clause that is processed and not to previous clauses. This entails that within embedded clauses new phrases are attached to the embedded clause and not the main clause.

Alternatively, lexically-driven accounts posit that syntactic interpretation is built on the semantic knowledge of the complement taking verbs (McDonald, Pearlmutter & Seidenberg, 1994; Lapata, Keller & Schulte im Walde, 2001). Lexically-driven accounts of processing are strongly related to expectation-based probabilistic accounts (Levy, 2008; Roland, Dick &

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Elman, 2007) under which the probabilistic knowledge of the distributional properties of different linguistic features impacts their processing. Therefore, in (8), the second NP will be interpreted as the object of the verb because “dress” is more frequent as a transitive rather than an intransitive verb. As such, the parser is lead to expect “dress” to be a transitive rather than transitive verb. For (9), it is the semantics of the verb “believe” and the nouns “judge” and “defendant” that make a transitive interpretation more likely, in other words, the meaning of the words makes this reading more plausible. In the aforementioned examples, different accounts don’t make conflicting predictions. This is not always the case.

The garden-path model is an account within a broader theoretical framework where processing is rigidly serial or stepwise. In this type of account, other factors such as word meaning or pragmatics are not assumed to play a role in initial parsing decisions (Ferreira, 2003; Ferreira & Henderson, 1991; Fodor, Bever & Garrett, 1974; Fodor & Ferreira, 1998, Fodor & Inoue, 1994; Frazier, 1987; Frazier & Rayner, 1990). Processing is assumed to be initially purely structural and independent of other sources of information. It is only at the later stages where non-syntactic cues becoming relevant. In this sense, processing under the garden-path model is assumed to be highly modular. Lexically-driven and probabilistic models belong to the opposite strand of theoretical accounts known as constraint-based models (MacDonald, Pearlmutter & Seidenberg, 1994; Seidenberg & McClelland, 1989). In these models multiple sources of information such as semantics or pragmatics are active from the onset of processing and assist in determining the interpretation. Processing is not assumed to be serial but also cues are utilised in parallel. As such processing is not posited as something modular but interactive. Evidence so far suggests that the parser in adults makes use of non-syntactic information to facilitate processing; such information may be related to lexical properties of the words in the sentences (e.g. Ferreira & Clifton, 1986; Trueswell, Tanenhaus & Kello, 1993 for the effects of animacy), prosody (Nakamura, Arai & Mazuka,

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2012; Papangeli & Marinis, 2010), discourse (Ferreira & Clifton, 1986). Another source of information which may be utilised is non-linguistic; the presence of two referents in a visual scene has been shown to facilitate processing by reducing or helping to avoid effects of misinterpretation (Tanenhaus, Spivey-Knowlton, Eberhard & Sedivy, 1995; Trueswell, Hill, Logrip & Sekerina, 1999; Spivey, Tanenhaus, Eberhard & Sedivy, 2002). The motivation for this is that the number of referents has a pragmatic function as the presence of the second referent for sentences like (7) triggers the need to provide a motivation for a modifier to a phrase in order to disambiguate, thus avoiding garden-path effects.

An alternative account which does not fall within either of these two strands is the theory of good enough processing (e.g. Ferreira, Bailey & Ferraro, 2002; Ferreira, Engelhard & Jones, 2009, Karimi & Ferreira, 2016). Under this account, processing is claimed to not always be structural but more heuristic in sentences which are difficult. In these cases, multiple different types of cue are assumed to be used as in constraint-based models. Language processing is posited as potentially only partial and the arising representations incomplete (Ferreira et al., 2009) or lacking in detail and that the parser may remain with the erroneous interpretation. Evidence for this can be drawn from the fact that people may respond positively to the question “Did Mary dress the baby?” when hearing a sentences as in (8), “While Mary dressed the baby slept” (Christianson et al. 2001). This is the wrong interpretation as the verb “dress” in this case is intransitive rather than transitive; the second NP in the sentences is, thus, in the absence of overt morphological case, interpreted as the object of the verb. The initial interpretation needs to be abandoned at the second verb as the ambiguous NP will be interpreted as a subject. The fact that participants respond to the comprehension question in a way that is consistent with a transitive reading of the verb “dress”, entails that the original misinterpretation persists. Under the good enough account, the representation built is posited to also be informed by schematic knowledge the speaker of a language may have.

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It should be noted that more recent accounts of good-enough processing do not ignore syntactic structure; reanalysis is assumed to take place. In fact, in more recent accounts, it is considered largely complete; the main tenet of good-enough processing accounts regarding the global interpretation of ambiguous sentences is that the initially assigned interpretation is not fully erased but that both interpretations seem to partially co-exist (for evidence for this see Slattery, Sturt, Christianson, Yoshida & Ferreira, 2013).

In sum, these two linguistic features tested are suitable to examine real time processing of sentences in bilingual children and adults, and to test key features observed in monolingual children but also adults such as incrementality, revision and reanalysis, and use of information from other sources in real time. The remainder of the chapter provides an overview of the main theoretical issues in sentence processing in bilingual children and bilingual adults as well as empirical evidence. It concludes with an outlining of the central research questions and an overview of the structure of this thesis.