Current Lecture: Sentence ProcessingSentence ComprehensionThe dog bites the manThe man bites the dogman the bites The dog.All 3 sentences have the same words but structure and meaning are different in 1 & 2 (3 is ungrammatical!)A grammar tells you what is possibleThematic role assignment tells you what the meaning isThematic Roles vs. Syntactic RolesThematic Roles—meaning basedSyntactic Roles—syntax basedThe ghost chased the vampireThe vampire chased the ghostThe vampire was chased by the ghostSo…Hear sentenceAssign each word to a roleUnderstand sentenceWhat’s hard about that?Sentence Comprehension is Hard because…Infinite number of possible sentencesSentence meanings (and words’ assignment to roles) cannot be stored in memoryOur memory won’t allow us to hold longish sentences in memory verbatimAmbiguityComplicates sentence comprehensionOccurs more than you might expectGives us a way to examine sentence processingMemory ConstraintsWorking memory allows us to hold a small number of things in mind and maintain the orderBefore we assign meaning to a sentence it is fundamentally a bunch of words in a listAmbiguityWord level ambiguityThe Desert TrainsGlobal (permanent) ambiguityOld men and women leave first.The cop stopped the robber with the gun.Local (Temporary) ambiguity—Garden Path SentencesThe horse raced past the barn fellThe old man the boatsIncrementalWe process language on a word-by-word basisDon’t wait to the end to start to figure out meaningAssign words to meaning as rapidly as possibleAttempt to anticipate meaningsThe woman will spread the butter…History—Kimball (1973)Parsing is top-downRight associationNew nodesOnly 2 S-nodes at onceClosureFixed structureCurrent Models of ProcessingGarden Path ModelConstraint Based ModelGarden Patho Model (2 stage—autonomous)Stage 1—build tree based on syntactic category informationIf info is ambiguous use minimal attachment and late closure to build 1 treeStage 2—check the semantics and see if it makes senseIf sentence doesn’t make sense revise the treeMinimal AttachmentForm the simplest possible tree (fewest nodes)Late ClosureAssume that incoming info attaches to the tree structure you already have (without a new major node).Because Jay always jogs a mile and a half this seems a short distance to him.Because Jay always jogs a mile and a half seems a very short distance to him.Constraint Based Model (1 stage—interactive)Stage 1—build lots of trees based on syntactic category information. Semantic information, contextual information, etc.if info is ambiguous create the obvious possibilitiesMay discard very low possibilities early onDecide between the choices based on which has the most activation at end of parsingAutonomous ModelInteractive ModelSemantics do NOT matterSemantics DO matterThematic roles are NOT influentialThematic roles affect parsing early onSemantic and syntactic processing ARE separableSemantic and syntactic processing are NOT separableOnly syntactic info causes garden pathsSemantic info can also cause garden pathsContextual information does NOT matterContext can affect processingFrequency information does NOT matterFrequency information does matterFerriera & Clifton, 1986Animacy is a reliable semantic cueThe defendant examined…The evidence examined…By the lawyer turned out to be unreliable____________didn’t affect reading timesVerbs & Thematic RolesCertain verbs tend to take certain thematic roles–Sneezed –agent–visited –agent,. ThemeThematic roles aren’t entirely dependent on meaning–eat/devourknowledge of verb themes might influence processingVan Gompel & Pickering (2001)After the child had visited the doctor prescribed a course of injectionsAfter the child had sneezed the doctor prescribed a course of injectionsEye movement study (reading) found no difference in sneezed vs. visited type sentencesTrueswell & Tanenhaus, 1994The fossil examined…The archeologist examined…Examined most frequently co-occurs with an animate subjectIf you give some contextual support the sentences are equally good.Osterhout & Nicol (1999)Taraban & McClelland 1988Milne 1982The granite rocks during the earthquakeThe granite rocks were by the seashoreThe table rocks during the earthquakeVerbal Context Altmann & Steedman 1988The burglar blew open the safe with the new lock and made off with the lootThe burglar blew open the safe with the dynamite and made off with the lootIf you tell a story beforehand… change the resultsVisual Context Tanenhaus and colleagues 1995Verb BiasSome verbs tend to occur in certain sentence frames more than in othersFinish the sentence:He thought…He heard…He saw the girl with the binocularsHe moved the turtle with the stickVerb Bias StudiesThe young athlete realized her potential…Realized ~ complement biasReader should expect more information to comeCsd 3117 1st Edition Lecture 15Outline of Last Lecture I. Development of the world’s writing systemsa. Orthographies II. Typical reading development in childhooda. U curveb. Stroop EffectIII. Reading Disordersa. Dyslexiab. Specific comprehension deficitc. Hyperlexiad. synesthesiaIV. Research relevanceOutline of Current Lecture V. Sentence ComprehensionVI. Thematic Roles vs. Syntactic RolesVII. Difficultiesa. Memory constraintsb. Ambiguityc. IncrementalVIII. HistoryIX. Current Models of Processinga. Garden Path Modelb. Constraint Based ModelX. Significant figuresa. Ferriera & Cliftonb. Van Gompel & Pickeringc. Trueswell & Tanenhausd. Osterhout & Nicole. Taraban & McClellandf. Milneg. Altmann &Steedmanh. Tanenhaus and colleaguesXI. Verb BiasThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Current Lecture: Sentence Processing- Sentence Comprehension- The dog bites the man- The man bites the dog- man the bites The dog.o All 3 sentences have the same words but structure and meaning are different in 1& 2 (3 is ungrammatical!)o A grammar tells you what is possibleo Thematic role assignment tells you what the meaning is- Thematic Roles vs. Syntactic Roleso Thematic Roles—meaning basedo Syntactic Roles—syntax basedo The ghost chased the vampireo The vampire chased the ghosto The vampire was chased by the ghost- So…o Hear sentenceo Assign each word to a roleo Understand sentence What’s hard about that?- Sentence Comprehension is Hard because…o Infinite number of possible sentences Sentence