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Evidence for imperfect adult performance

Depth of processing in language comprehension: not noticing the evidence, A. J. Sanford and P. Sturt, Trends in Cognitive Sciences 6:382-386 (2002). Good-enough representations in language comprehension, F. Ferreira, K. G. D. Bailey, and V. Ferraro, Current Directions in Psychological Science 11:11-15 (2002). Constraints on sentence comprehension E. Gibson and N. Pearlmutter,, Trends in Cognitive Science 2:262-268 (1998).

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How people compose the meanings of sentences from individual words

The government has other agenciesand instruments for pursuing these other objectives

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The Good enough approach to language comprehension holds that language processing is sometimes only partial and that semantic representations are often incomplete

Traditional theories assume that sentenceprocessing is algorithmic and that meaning is derived compositionally

But there is a new approach the argues with that.

Good-enough representations in language comprehension

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Depth of processing in language comprehension: not noticing the evidence

The time-course of processing

The depth of processing

There are two factors to be consider while analyzing sentences:

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Models of sentence processing

Garden-path model

Constraint-satisfaction model

Example: “Mary saw the man with the binoculars”

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While analyzing the sentence, not all the evidence are noticed.Thus the use of lexical semantics can be far from complete.

To the question :“How many animals of each sort did Moses put on the ark?”

Is the meaning of a sentence always the sum of its parts?

This also show that people unconsciously normalize strange sentences to make them sensible.

Many people answered two.Instead of thinking about the meaning behind the question.

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Another experiment done by Barton and Sanford tested the ‘survivors’ anomaly, to the question

‘After an aircrash, where should the survivors be buried?’injured

Half of the participants gave an answer like ‘bury them where their relatives want’

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Pragmatic and discourse influences on processing depth

Like in the survivors example before, sometimes earlier knowledge is used in order to understand the meaning of the sentence. This is called Depth Charge.

Example:

No missile is too small to be banned

No head injury is too trivial to be ignored.

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Recent studies of whether interpretations are good enough

Misinterpretations of Garden-Path Sentences

Version 1 Version 2

Do people delete from memory their initial misinterpretation of a sentence after reanalysis?

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Recent studies of whether interpretations are good enough

Misinterpretations of Garden-Path Sentences

Example:

While Anna dressed the baby played in the crib.

(1) Did the baby play in the crib?(2) Did Anna dress the baby?

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Misinterpretations of Garden-Path Sentences

The goal of the experiment:

Are people ever tricked by simple, but implausible, passive sentences?

(1) The man bit the dog.(2) The man was bitten by the dog.(3) The dog bit the man.(4) The dog was bitten by the man.

When people read or hear a passive sentence, they use their knowledge of the world to figure out who is doing what to whom.

Recent studies of whether interpretations are good enough

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The challenges in comprehension

The structure built by the language processor is fragile and decays rapidly ,that’s why the representation needs almost immediate support from context or from schemas.

The linguistic system must cope with potentially interfering information.

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What makes a structure likely to be misinterpreted?

Passives require semantic roles to be assignedin an atypical order

One example of a language that allows some freedom in the active and passive is Odawa.

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For example:

(1) Mary bought a brand new radio.

(2) It was in Selfridge’s window.

(3) Later, when Joan saw it, she too decided it would bea good purchase.

Many processes are incomplete, and that interpretations are not as full as possible, but are often ‘underspecified’.

Interpretations are not always full

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Shallow processing in computational linguistics

The sentence is not always fully analyzed.

It depend on the requirement for a full/shallow analysis

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Underspecification in human language understanding

Scope disambiguation

The selection of word meanings in cases of ambiguity of meaning

Underspecification can be caused in three cases:

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Scope disambiguation

The selection of word meanings in cases of ambiguity of meaning

Underspecification in human language understanding

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Scope disambiguation

(1) Kelly showed every photo to a critic last month.

(2) The critic was from a major gallery.

(3) The critics were from a major gallery.

If underspecified representations are used by humans, then people should be able to integrate the meaning of a multiply-quantified sentence without committing to any one scope ordering

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(a) [ The scientist collaborates with the professor [who had advised the student [ who copies the article] ] ]

(b) [The student [who the professor [ who the scientist collaborated with ] had advised ] copied the article]

Sentences with a complex scoping can be harder to understand

Example:

you

SAS

SASB

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Underspecification in human language understanding

Scope disambiguation

The selection of word meanings in cases of ambiguity of meaning

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Some words have several meanings ,the question is do readers select between them?

In the experiment two types of words were cheeked

Words like:

pupil - student/part of eye

newspaper – printed paper/company

Vietnam – the country/the war

Ambiguity of meaning

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Amanda believed the senator….

(a)… during the speech

(b)… was lying to the committee.

There are also problematic words like believe

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Focus and subordination

The word order, or the right question, can focus our attention on a specific word.

For example in the Moses illusion:

It was Moses who put two of each kind of animal on the ark. True or False?

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Principle of compositionality

Socrates was a man

S was a M

Meaning of a complex expression is determined by the meanings of its constituent expressions and the rules used to combine them.

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Text change – detection: Changing the words in the sentence, after seeing it

(A) The newsagent had just hired a new paperboy tocover the downtown area. The paperboy finished hisrounds after he ate his breakfast. There were a lot ofdeliveries to be made.

completed

(B) The newsagent had just hired a new paperboy tocover the downtown area. After the paperboy finishedhis rounds, he ate his breakfast. There were a lot ofdeliveries to be made.

started

0

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30

40

50

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Semantic distance between the replaced words

Per

cen

tag

e o

f co

rrec

t u

nse

rin

g

(A) sentance

(B) sentance

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Conclusions

Good-enough interpretations help the language system coordinate listening and speaking during conversation.

Subordination and focus represent ways of signaling what is important in a discourse, and we have seen how they play a role in determining depth of processing.

We saw today that:

Some sentences are not analyzed always completely.

Parts of the sentence that aren’t analyzed are added from our previous experience or context