The online processing of semantic and pragmatic content Brian - PDF document

The online processing of semantic and pragmatic content Brian Dillon LINGUIST510

Psycholinguistics Comprehension: How do we compute the meaning of a sentence in real time? What are the online computations that we use to map word strings to structured meanings when reading or listening? grammatical knowledge (extra-)linguistic context [[words]] words memory attention

Psycholinguistics - What is the grammatical / cognitive mechanism that achieves (scalar) implicature? Some students enjoy psycholinguistics.

The Garden Path The horse raced past the barn fell BEVER (1970)

The Garden Path The horse raced past the barn fell - Syntactic analysis proceeds incrementally - The ‘ main verb’ parse of ‘raced’ is preferred over the ‘reduced relative’ parse BEVER (1970)

The Garden Path The horse raced past the barn fell - Garden Path Theory: main verb analysis is preferred because it is structurally simpler: there are fewer syntactic nodes/phrases to postulate on MV analysis. So it is computed more rapidly, and becomes the parse we initially adopt.

The Garden Path The horse raced past the barn fell - Pragmatic Theory (?): main verb analysis is in some sense “pragmatically preferred” over reduced relative analysis (in the so-called ‘null context’). Such a theory would imply that pragmatic computations occur incrementally.

The Garden Path Suppose that comprehenders incrementally interpret sentences, including presuppositions, implicatures. Then… MV: [ NP The horse] raced … - What are presuppositions, implicatures generated by this (partial) parse? RR: [ NP The [ RC horse raced … ] ] - What are presuppositions, implicatures generated by this (partial) parse?

The Garden Path MV: [ NP The horse] raced … There’s a (unique) horse RR: [ NP The horse raced … ] … There is a (unique) horse which +1 ) is a member of some larger set of horses. +2 ) This horse was raced somewhere and +3 ) the other horses weren’t raced to this place…

The Referential Theory MV: [ NP The horse] raced … RR: [ NP The horse raced … ] … Principle of Parsimony (Crain & Steedman 1985): Parse which carries fewer unsatisfied presuppositions/ entailments ( implicatures-BWD) is adopted by hearer, all else being equal. Explains Garden Path effect: RR analysis carries ~3 more unsupported implicatures (in ‘null context’) than MV parse, so is dispreferred.

The Referential Theory MV: [ NP The horse] raced … RR: [ NP The horse raced … ] … Prediction: The probability of experiencing a garden path should decrease with the number of implicatures associated with a reduced relative parse of input string.

The Referential Theory Def: The children taught by the Berlitz Method passed the test. Bare plurals, existential: Children taught by the Berlitz method passed the test Bare plurals, generic: Children taught by the Berlitz method pass the test Experiment: Use Rapid Serial Visual Presentation (300ms/word), and ask for rapid grammaticality judgment. CRAIN & STEEDMAN (1985)

The Referential Theory + CRAIN & STEEDMAN (1985)

The Referential Theory YOUNGSTERS CRAIN & STEEDMAN (1985)

The Referential Theory PUSHED CRAIN & STEEDMAN (1985)

The Referential Theory INTO CRAIN & STEEDMAN (1985)

The Referential Theory THE CRAIN & STEEDMAN (1985)

The Referential Theory COULDN’T CRAIN & STEEDMAN (1985)

The Referential Theory MOVE CRAIN & STEEDMAN (1985)

The Referential Theory ???? CRAIN & STEEDMAN (1985)

The Referential Theory + CRAIN & STEEDMAN (1985)

The Referential Theory YOUNGSTERS CRAIN & STEEDMAN (1985)

The Referential Theory PUSHED CRAIN & STEEDMAN (1985)

The Referential Theory INTO CRAIN & STEEDMAN (1985)

The Referential Theory THE CRAIN & STEEDMAN (1985)

The Referential Theory CROWD CRAIN & STEEDMAN (1985)

The Referential Theory COULDN’T CRAIN & STEEDMAN (1985)

The Referential Theory MOVE CRAIN & STEEDMAN (1985)

The Referential Theory ???? CRAIN & STEEDMAN (1985)

The Referential Theory % “UNGRAMMATICAL” Responses: Definite heads > Indefinite Existentials > Indefinite Generics (29%) CRAIN & STEEDMAN (1985)

The Referential Theory “Syntax proposes, semantics disposes”: The parser incrementally generates a semantic interpretation+presuppositions+implied meaning in parallel for some (maybe all) possible parses, and uses the latter to select a parse for further computation. CRAIN & STEEDMAN (1985)

The Referential Theory Can other linguistic operators introduce contexts that support RR parses fast enough to prevent garden pathing? Focus operator only requires contrast set (viz. focus alternatives). Can a focus operator that needs a contrast introduce bias towards postmodifier parse of ambiguous material?

The Referential Theory Bare, Def: The businessmen loaned money at a low interest rate were told to record their expenses. Only, Def: Only the businessmen loaned money at a low interest rate were told to record their expenses. CRAIN, NI & SHANKWEILER (1996)

The Referential Theory / ( Only ) the businessmen/ loaned/ money at a low/ interest rate/ were told / to record their/ expenses/ Experiment: Self-paced reading. Readers see one section of sentence at a time, and they press a button to advance through the sentence. Reaction times to the button press are recorded; processing difficulty is expected to surface as long reaction times. CRAIN, NI & SHANKWEILER (1996)

The Referential Theory / ( Only ) the businessmen/ loaned/ money at a low/ interest rate/ were told / to record their/ expenses/ ms CRAIN, NI & SHANKWEILER (1996)

The Referential Theory / ( Only ) the wealthy businessmen/ loaned/ money at a low/ interest rate/ were told / to record their/ expenses/ ms CRAIN, NI & SHANKWEILER (1996)

The Visual World

The Visual World Recognize “apple” 150ms Fixate “apple”

Tanenhaus et al (1995) Ambiguous Instruction: “ Put the apple on the towel in the box” Parse 1: “Put [ the apple on the towel] in the box” Parse 2: “Put [ the apple ] [on the towel] in the box”

Tanenhaus et al (1995) Unambiguous Instruction: “ Put the apple that’s on the towel in the box”

Tanenhaus et al (1995) “ Put the apple on the towel in the box” 2-Referent Context 1-Referent Context

Tanenhaus et al (1995) 1-Referent Context In 1-referent context with ambiguous instructions, listeners look to incorrect goal ( B ), suggesting they’ve been garden- pathed.

Tanenhaus et al (1995) 2-Referent Context In 2-referent context with ambiguous instructions, listeners do not look to incorrect goal ( B ).

Tanenhaus et al (1995) i) uniqueness presupposition for determiner calculated immediately, ii) presupposition immediately evaluated against extra-linguistic (visual) context… iii) … biasing listeners to postmodifier parse of ambiguous PP

Tanenhaus et al (1995) Implication: The need to satisfy the uniqueness presupposition of definite the 2-referent context causes comprehenders to anticipate a PP postmodifier!

‘Continuous referential processing’ So far: Listeners rapidly compute presuppositions and implicatures off of partial input; Use this information to information syntactic parsing decisions; Continuously evaluate presuppositions and implicatures against (extra-)linguistic context

Scalar implicatures Question: Why should comprehenders attempt to minimize unsatisfied implicatures a la Parsimony? Why not make ALL the implicatures and just deal with it? Hypothesis: The calculation of an implicature is a cognitive operation with measurable cost; it is to be avoided, all else being equal.

Scalar implicatures Some students enjoy psycholinguistics. Lower-bounded reading: some, maybe all, students like psycholx Upper-bounded reading: some, but not all, students like psycholx HUANG & SNEDEKER (2009)

Scalar implicatures Some students enjoy psycholinguistics. Hypothesis : Derivation of upper-bounded reading involves computation of scalar implicature, which requires an extra processing step. Some Some, Some, not compute scalar maybe all all access literal meaning implicature HUANG & SNEDEKER (2009)

Scalar implicatures Some students enjoy psycholinguistics. Prediction : We should observe that comprehenders i) are slower to access upper-bounded reading than lower- bounded and ii) should show evidence lower-bounded reading at some point in processing stream. Some Some, Some, not compute scalar maybe all all access literal meaning implicature HUANG & SNEDEKER (2009)

Scalar implicatures Point to the girl that has some/two of the socks…

Scalar implicatures Two : Point to the girl that has two … Only compatible with this referent.

Scalar implicatures Some : Point to the girl that has some … If lower-bound reading computed first, reference is ambiguous here.

Scalar implicatures Some : Point to the girl that has some … If upper-bound reading computed immediately, sentence is only compatible with this referent.