PSY 369: Psycholinguistics Language Comprehension: The role of memory

Center embedded structures The house burned down. The house the handyman painted burned down. He sent a letter about it to Galileo, the great Italian scientist.

Memory and comprehension Brief summary so far: What is the role of syntax in comprehension? Syntax is important for getting the right interpretation during on-line comprehension There is a lot of research examining what factors influence the on-line construction of syntax e.g., parsing principles, lexical semantics, plausibility, discourse context Today: What is the role of Memory in language comprehension?

Memory for sentences Fillenbaum (1966) Given: The window is not closed Tested: The window is not closed The window is closed The window is not open The window is open <-- surface similar, meaning different <-- surface different, meaning similar Most common error Conclusions: Meaning gets preserved, surface structure (and syntax) forgotten

Memory for sentences Think back to the beginning of class. Which of the following sentences did you read? Galileo, the great Italian scientist, sent him a letter about it. He sent Galileo, the great Italian scientist, a letter about it. He sent a letter about it to Galileo, the great Italian scientist. A letter about it was sent to Galileo, the great Italian scientist.

Memory for sentences Sachs (1967, 1974) Heard (read): “He sent a letter about it to Galileo, the great Italian scientist.” Tested: Same: He sent a letter about it to Galileo, the great Italian scientist. Act/Pass: A letter about it was sent to Galileo, the great Italian scientist. Formal: He sent Galileo, the great Italian scientist, a letter about it. Meaning: Galileo, the great Italian scientist, sent him a letter about it. Measured accuracy of detecting changes

Memory for sentences Conclusions: Meaning gets preserved, surface structure (and syntax) forgotten Sachs (1967, 1974)

Just good enough representations Ferreira and colleagues (Christianson et al 2001) Garden-path sentence While Anna dressed the baby played in the crib While Anna dressed, the baby played in the crib 100% correct 40% correct Comprehenders don’t always get all of the meaning right, but get enough to get by Did the baby play in the crib? Did Anna dress the baby?

Memory and comprehension Brief summary so far: What do we remember about sentences? Syntax may not be too important later, we remember the meaning of sentences but not so much the form (syntax) of the sentence

Center embedded structures The house burned down. The house the handyman painted burned down. The house the handyman the teacher hired painted burned down. This sentence is syntactically legal. So why is it so hard to comprehend? One possibility is that there are limitations as a result of our cognitive systems

Center embedded structures The house burned down. Memory and comprehension

The house the handyman painted burned down. Center embedded structures The house burned down. Memory and comprehension

This one may be legal, but that doesn’t mean that it is (easily) comprehensible ( the handyman that the teacher hired painted the house that burned down ) The house the handyman the teacher hired painted burned down. Center embedded structures The house burned down. The house the handyman painted burned down.

Memory and comprehension VP V laughed NP the woman S NP The man NP RR C that RR C that NP The child VP hugged V VP kissed V Typically we build right branching structures But here there is a big series of branches down the center The man that the woman that the child hugged kissed laughed.

Memory and comprehension Possible explanation for the trouble: Insufficient working memory resources to retain the intermediate products of computation made building the complex syntactic structure The man that the woman that the child hugged kissed laughed. Most readers having trouble figuring out who did what to whom (called thematic role assignment). Easier to assign thematic roles in the two sentences that form it: The man that the woman kissed laughed. The woman that the child hugged kissed the man.

Memory: a brief review InformationInformation ‘flows’ from one memory buffer to the next Information

Memory: a brief review Properties Organization Multiple subsystems for type of memory Syntax within the procedural domain (e.g., Ullman, 2004) Semantics as Associative networks Declarative Procedural episodic semantic

Memory: a brief review Properties rapid access (about 35 milliseconds per item) limited capacity (7+/- 2 chunks; George Miller, 1956)George Miller, 1956 fast decay, about 12 seconds (longer if rehearsed or elaborated)

Working Memory Working memory instead of STM Working memory

Working Memory Working memory instead of STM Phonological rehearsal mechanism Phonological store Very limited capacity Rehearsal maintains information in the store

Working Memory Working memory instead of STM Store and manipulate visual and spatial information Directly from perception Indirectly from imagery

Working Memory Working memory instead of STM Allocate attentional resources to the subcomponents Directs elaboration/manipulation of information

Measuring memory span Increasing your STM spanSTM span Chunking Grouping information together into larger units I’ll read a few more lists of words for you to recall barn snow tree car rock book key plant dress cup slide lamp dog cat mouse shoe sock toe couch pillow blanket table desk chair down flowers the by with chased yellow several girls a river boy a boy chased several girls with yellow flowers down by the river Notice that the previous two are the same words, but the syntax allows for grouping into meaningful ‘chunks’

Daneman and Carpenter (1980) Technique: This technique involves presenting sequences of 2 to 6 sentences, each of 12 to 17 words. The participant has to read the sentences out loud, and attempt to remember the last word of each. Then asked to recall as many last words as possible (in any order). Measuring memory span

When at last his eyes opened, there was no gleam of triumph, no shade of anger. Measuring memory span

The taxi turned up Michigan Avenue where they had a clear view of the lake. Measuring memory span

Recall the last words Measuring memory span When at last his eyes opened, there was no gleam of triumph, no shade of anger. The taxi turned up Michigan Avenue where they had a clear view of the lake.

I turned my memories over at random like pictures in a photograph album. Measuring memory span

I will not shock my readers by describing the cold-blooded butchery that followed. Measuring memory span

He had an odd elongated skull which sat on his shoulder like a pear on a dish. Measuring memory span

You can check out the books that you need for this course at the local library. Measuring memory span

The radio station was promoting the concert with free tickets and back stage passes. Measuring memory span

The professor could be seen on weekends in the backyard garden pulling out weeds. Measuring memory span

Recall the last words Measuring memory span I turned my memories over at random like pictures in a photograph album. I will not shock my readers by describing the cold-blooded butchery that followed. He had an odd elongated skull which sat on his shoulder like a pear on a dish. You can check out the books that you need for this course at the local library. The radio station was promoting the concert with free tickets and back stage passes. The professor could be seen on weekends in the backyard garden pulling out weeds. Ok for two sentences; Hard at 3 sentences; Very hard for 4 or more. Used to classify readers as high and low span (there is a “speaking span” version too)

Memory and online comprehension The Capacity Theory of Comprehension (Just & Carpenter, 1992) Proposed that individual differences in working memory capacity should influence how readers comprehend sentences

Memory and online comprehension The animacy of the first noun may constrain the possible interpretation of the sentence Semantically Unconstrained: The defendant examined by the lawyer shocked the jury. The defendant that was examined by the lawyer shocked the jury. Semantically Constrained (so should be faster if animacy can be used) The evidence examined by the lawyer shocked the jury. The evidence that was examined by the lawyer shocked the jury. “that was” disambiguates these sentences The Capacity Theory of Comprehension (Just & Carpenter, 1992) Proposed that individual differences in working memory capacity should influence how readers comprehend sentences

Memory and online comprehension Just the ambiguous sentences The defendant examined by the lawyer shocked the jury. The evidence examined by the lawyer shocked the jury. High span readers could use the semantic information to resolve the ambiguity

Memory and online comprehension King and Just (1991) Verbs which could provide strong pragmatic cues as to which of the two potential actors in the sentence was the agent: The robber that the fireman rescued stole the jewelry. Embedded clause Two possible agents: the robber the fireman Two verbs, which is the main verb of the sentence?: rescued stole

Memory and online comprehension King and Just (1991) Verbs which could provide strong pragmatic cues as to which of the two potential actors in the sentence was the agent: The robber that the fireman rescued stole the jewelry.. The robber that the fireman rescued watched the program. The robber that the fireman detested stole the jewelry. The robber that the fireman detested watched the program. Can bias which Noun goes with which Verb pragmatically (or not) Questions: Can speakers use this information? Does memory have an impact? Strong bias No bias

Memory and online comprehension King and Just (1991) Verbs which could provide strong pragmatic cues as to which of the two potential actors in the sentence was the agent: The robber that the fireman rescued stole the jewelry. The robber that the fireman rescued watched the program. The robber that the fireman detested stole the jewelry. The robber that the fireman detested watched the program. Main verbEmbedded relative verb

Memory and online comprehension King and Just (1991) Verbs which could provide strong pragmatic cues as to which of the two potential actors in the sentence was the agent: Results Low-capacity subjects had lower comprehension overall & slower reading in syntactically difficult regions High-capacity subjects did NOT improve with pragmatic info Low-capacity subjects did improve with pragmatic info Comprehension accuracy bothrelVmain V neither H H H H L L L L Method Word-by-word moving window procedure Data % correct on a T/F comprehension question when relative clause is tested Reading times by region

Memory and online comprehension Garnsey, Pearlmutter, Pirog (2003) The professor (who was) confronted by the student was not ready for an argument. The professor (had) confronted the student but was not ready for an argument. Question: Do readers differ specifically in how quickly they can use disambiguating words to rule out incorrect alternatives?

Memory and online comprehension - By whether preview of “by” while still fixating on verb likely Eye fixations were analyzed separately The professor confronted by the student was not ready to … Garnsey, Pearlmutter, Pirog (2003) If last fix was here, trial not used If last fix was here, trial coded as Preview Unlikely If last fix was here, trial coded as Preview Likely

Memory and online comprehension Readers who score high on the Reading Span test - Make better use of a peripherally visible disambiguating word to quickly rule out a preferred but incorrect interpretation

Memory and online comprehension What information is used to resolve syntactic ambiguities depends on individuals working memory capacity (but see Walters and Caplan (1996) for alternative view) Just & Carpenter (1992) - high span readers used semantic information early, but low span readers didn’t King & Just (1991) - high span readers did not use pragmatic information to resolve ambiguity, but low span readers did Garnsey, Pearlmutter, Pirog (2003) - span differences may also depend on where the eye lands (which determines what kind of preview readers get)

Memory and comprehension Brief summary so far: What do we remember about sentences? Syntax may not be too important later, we remember the meaning of sentences but not so much the form (syntax) of the sentence What is the role of syntax in comprehension? Syntax is important for getting the right interpretation during on-line comprehension Memory capacity may play an important role in determining what kinds of information we can use to comprehend sentences

Memory and comprehension There is room for about 15 more mins. Of material (for next semester)