Lecture 11_language.pdf

PSYC 5140 Cognitive Psychology Lecture 10: Language 2023 Instructor: Urs Maurer What Is Language? • Language: System of communication using sounds or symbols that enable us to express feelings, thoughts, ideas, and experiences Animal Communication • Ants: Chemical messengers (pheromones) • Ho...

PSYC 5140 Cognitive Psychology Lecture 10: Language 2023 Instructor: Urs Maurer What Is Language? • Language: System of communication using sounds or symbols that enable us to express feelings, thoughts, ideas, and experiences Animal Communication • Ants: Chemical messengers (pheromones) • Honey bees: – Waggle dance – Direction, distance • Primates: visual, auditory, tactile, olfactory signals – Vervet monkey: • Different warning calls for snake, eagle, and leopard https://www.youtube.com/watch?v=q8ZG8Dpc8mM https://www.youtube.com/watch?v=-7ijI-g4jHg What Is Language? • Language: System of communication using sounds or symbols that enable us to express feelings, thoughts, ideas, and experiences • Animal communication is much more rigid than human language – Limited number of sounds or gestures – About a limited number of things • Human language uses a wide variety of signals that are combined in countless ways Creativity of Human Language • Language makes it possible to create new and unique sentences because it has a structure that is: – Hierarchical system • Components that can be combined to form larger units • Speech sounds, words, sentences – Governed by rules • Specific ways components can be arranged The Universality of Language • Language has been called “universal” because it occurs wherever there are people • Deaf children invent sign language that is all their own • All humans with normal capacities develop a language and learn to follow its complex rules • Language is universal across cultures • Language development is similar across cultures – Babbling, first word (1 y), multi-word (2y) • Languages are “unique but the same” – Different words, sounds, and rules – All have nouns, verbs, negatives, questions, past/present tense Time Line of Language Evolution • Homo sapiens diverged from other species between 2 Mio and 300’000 years ago • Articulatory tract • No change in last 60’000 years • Evolutionary risk • More likely to choke • Language must have an advantage Brain Size and Language • Evolutionary development of pharyngeal area • Evolution of human vocal tract – Estimated that vocal tract evolved 125’000 years ago pharynx • Brain size increased substantially earlier: – 2-3 mio years ago • Suggests: brain size increased before vocal tract developed • What was driving increase in brain size? ↑– Social group size verbal ↑– Correlates with brain size (Dunbar, 1998) include non-verbal – Social cognition more important, e.g., theory of mind – Group size estimated on brain size: 150 (weddings and funerals) , . Studying Language in Cognitive Psychology • B.F. Skinner (1957) Verbal Behavior (book) – Language learned through reinforcement • Reward for correct language, punishment/no reward for incorrect language • Noam Chomsky (1957) Syntactic Structures – Human language coded in the genes – Underlying basis of all language is similar – Children produce sentences they have never heard and that have never been reinforced creative in • “I hate you, Mommy” using language – Studying language as a way to study the properties of the mind Studying Language in Cognitive Psychology • Psycholinguistics: discover psychological process by which humans acquire and process language – Comprehension: • How do people understand spoken and written language? – Speech production: • How do people produce language? – Representation: • How is language represented in the mind and in the brain? – Acquisition: • How do people learn language? Perceiving and Understanding Words • One of the most amazing things about words is how many we know and how rapidly we acquire them – Adults can typically understand more than 50,000 different words • Stored in lexicon (= all the words we know): – Our knowledge of words – how they sound (phonology) – what they mean (semantics) – how they are used (in relation to other words) (syntax) Perceiving and Understanding Words • The two smallest units of language are: speech sound – Phonemes: shortest segments of speech that, if changed, changes the meaning of the word - • bit => /b/, /i/, /t/ how many morphemes/ phonemes in this word ‘shoes’? morphemes: 2 ; phonemes: 3 – Morphemes: smallest units of language that has meaning or grammatical function - • table => 1 morpheme • bedroom => 2 morphemes (free morphemes) • tables => 2 morphemes (-s changes meaning) (bound morphemes) – How many phonemes and morphemes? • shoes Problem of Perceiving Words • Not everyone says words the same way – Different accents – Different speeds – Relaxed approach to speaking in natural speech • «did you?» or «dijoo»? • 50 different ways to pronounce «the» • «Schwa»: most common vowel sound in English, reduced vowel in unstressed syllables • No clear word boundaries in continuous speech Perceiving and Understanding Words • Phonemic restoration effect https://www.youtube.com/ watch?v=_CJDEMj7jdw – Occurs when phonemes are perceived in speech when the sound of the phoneme is covered up – “Fill in” missing phonemes based on context of sentence and portion of word presented – Subjects can’t tell when the cough takes place – Example of top-down processing – The meaning of words that follow the missing phoneme also what we perceive the phoneme as (Warren, 1970) Perceiving and Understanding Words • Speech segmentation: perceiving individual words in a sentence – Context: when taken out of context and presented alone, words become much more difficult to understand • Subjects being presented with their own speech, but segmented, could only identify only half of the words – Understanding of meaning: • “I scream, you scream, we all scream for ice cream” – sounds identical, context defines how they are heard • A few familiar words pop out in a stream of otherwise unfamiliar language – Statistical probabilities of sound patterns • Certain sounds are more likely to be separated by space between two words • “Pretty baby”, it’s likely that ty and ba will be separated by space Reading: The Word Superiority Effect ~ fastest • A stimulus that is either a word, letter, or non-word if flashed briefly • Followed by a mask • Two letter are presented rapidly • S task is to pick the flashed letter that was presented • Letters are easier to recognize when they are contained in a word than when they appear alone or are contained in a nonword context help with perception (Reicher 1969) Understanding Words • People have lexicons: know the meaning of ~50,000 words • How are words used in a particular language: – Create a large representative sample of utterances or written text – Called a corpus – indicates frequency of: • words, different meanings, and grammatical constructions – Useful: a lot in language comprehension is related to prediction • See Chapter 3: regularities in environment • See Chapter 8: memories influenced by world knowledge – Our ability to perceive written words depends on how frequently they Reason - appear in our lexicon make use of prediction Understanding Words • Word frequency effect – Respond more rapidly to high-frequency words – More rapid response to ‘home’ compared to ‘hike’ • Home: 547 times/million; hike: 4 times/million 1) Lexical decision task – Read a list of words and non-words silently – Say “yes” when you read a word – Faster for words that are more frequent 2) Eye movements while reading – Look at low-frequency words longer Understanding Words • Lexical ambiguity – Some words have more than one meaning • Duck: 1. ‘I saw her eating duck’ 2. ‘I saw her duck’ – Some meaning of words are more likely • “Many words have multiple meanings, but these meanings are not all created equal” (Traxler, 2012) • (see next slide) – Context clears up ambiguity after all meanings of a word have been briefly accessed Understanding Words • Meaning dominance – The fact that some meanings of a word are used more frequently than others – Biased dominance • When words have two or more meanings, and one meaning occurs more often than other meanings – tin: type of metal (dominant), small metal container of food – Balanced dominance • When words have two or more meanings with about the same frequency of occurrence – Cast: member of a play, plaster cast • Difference between biased and balanced dominance influences the way people access the meanings of words Understanding Words DV: fixations time In “the cast worked …”: •Both meanings of “cast” are activated •S looks longer at “cast” compared to control “cook” In “the tin was…”: •Biased meanings of “tin” is activated •S read the bias ambiguous word “tin” as fast as a control word Understanding Words Meaning frequency isn’t the only factor that determines the accessibility of the meaning of a word Context also plays a major role “The miners went to the store and saw that they had beans in tin” (control cup) ➔ the context indicates the less frequent meaning of tin ➔Both meanings get activated ➔Takes longer than “cup” Here context activates only the dominant meaning of “tin” ➔As fast as control Understanding Words • Accessing meaning is complicated and influenced by multiple factors – Frequency of a word – Relative frequency of a meaning, when word has multiple meanings – Context From Words To Sentences • Components of language are not processed in isolation • To understand how words create the meaning of a sentence, we first need to distinguish between the following: • Semantics: meanings of words in sentences – Changing “The cats won’t eat” to “the cats won’t bake” results in an error in semantics • Syntax: rules for combining words into sentences – Changing “The cats won’t eat” to “the cats won’t eating” results in an error in syntax Understanding Sentences • The study of brain-damages patients has provided evidence that syntax and semantics are processed in different areas of the brain – Broca’s area (in the frontal lobe) – Wenicke’s area (temporal lobe) • Broca’s aphasia: slow, labored, ungrammatical speech, and have problem understanding some types of sentences – The apple was eaten by the girl (no difficulty) – The boy was pushed by the girl (problem understanding this sentence) ➔ problems with syntax (or rather selection among competing sources of information) • Wernicke’s aphasia: not only produce meaningless speech but are unable to understand speech and writing – Don’t understand either of the above two sentences ➔ problems with semantics Understanding Sentences • Event-related potential (ERP) studies have shown syntax and semantics are associated with different mechanisms • ERP is a rapid response, occurring on a time scale of a fraction of a second • It consists of a number of components that occur at different delays (latencies) after a stimulus is presented • Two components that respond to different aspects of language are the N400 and the P600 Understanding Sentences N400 response is associated with structures in the temporal lobe. Damage to the temporal lobe reduces N400 P600 response is associated with structures in the frontal lobe. Damage to the frontal lobe reduces P600 Understanding Sentences • Parsing: mental grouping of words in a sentence into phrases – Central process for determining the meaning of a sentence • Garden path sentences – Sentences that begin by appearing to mean one thing, but then end up meaning something else – “After the musician played the piano..” – “she left the stage”, “she bowed to the audience” – “was wheeled off of the stage” • Temporary ambiguity – When the initial words are ambiguous, but the meaning is made clear by the end of the sentence Understanding Sentences • Sentences with temporary ambiguity can help us understand the mechanisms that operate during parsing • Syntax-first approach to parsing: – as people read a sentence, their grouping of words into phrases is governed by a number of rules that are based on syntax – If readers realize there is something wrong with their parsing, then they take other information into account in order to reinterpret the sentence – Late closure: parser assumes new word is part of the current phrase ➔ each new word is added to the current phrase for as long as possible Understanding sentences • [After the musician played] • [After the musician played the] • [After the musician played the piano] • [After the musician played the piano was] • [After the musician played the piano was wheeled] • [After the musician played] [the piano was wheeled] (X) X Understanding Sentences • Interactionist approach to parsing – Semantics and syntax both influence processing as one reads a sentence – The spy saw the cop with the telescope. • [The spy saw the cop] [with a telescope] • [The spy saw] [the cop with a telescope] – The bird saw the man with a telescope • [The bird saw] [the cop with a telescope] • Semantics influences the way we interpret the relationship between the words in a sentence Understanding Sentences • Our interpretation of a sentence is also influenced by the meaning of a scene we may be observing • Tanenhaus and coworkers (1995) – Visual world paradigm: involves determining how people process information as they are observing a visual scene – Eye movements change when information suggests that revision of interpretation of sentence is necessary – Syntactic and semantic information used simultaneously Understanding Sentences “Place the apple on the towel in the box” • Temporarily ambiguous: • “Place the apple on the towel” (eye movement to second towel) • “in the box” (garden path sentence, ambiguity resolved) (eye movement back to apple, then to box) If ambiguity is removed (“Place the apple that’s on the towel to the box”), then attention focuses immediately on box Understanding Sentences Two-apple condition: • “Place the apple on the towel in the box” • Sentence ambiguous, but participants expect information about which apple: • The relevant apple is the one on the towel • Participants do not look at other towel The interactionist approach predicts: when there are two apples, subjects expect the speaker to immediately let them know which apple -> in agreement with interactionist approach Understanding Sentences • We often use language as we interact with the environment • We also continually use our knowledge of the environment to make predictions about what we are about to read or hear – “Getting himself and his car to work on the neighboring island was time consuming. Every morning he drove for a few minutes, and then boarded the …” – We can easily complete this sentence (“ferry”) – This goes beyond syntax and semantics – We rely on our knowledge about the environment Understanding Sentences • Using knowledge about language construction • Our experience with sentence constructions can also influence how we predict that a sentence will be organized More frequent 1. The experienced soldiers warned about the dangers before the midnight raid 2. The experienced soldiers warned about the dangers conducted the midnight raid Garden path • • • “warned” can occur as main verb or relative clause Main verb more frequent Used in sentence 2 leads to garden path Understanding Text and Stories • Stories are more than the sum of the meaning of individual sentences – Well-written story: • Sentence in one part of story is related to sentences in other parts • Reader’s/listener’s task: – Use relationship between sentences to create coherent, understandable story – Important part: making inferences • Use knowledge that goes beyond what is written in text – Unconscious inference (Chap 3) & Constructive nature of memory (Chap 8): we use our knowledge to make inferences Understanding Text and Stories • Early demonstration of inference in language (Bransford & Johnson, 1973) Make inference “John was trying to fix the birdhouse. He was pounding the nail when his father came out to watch him and help him do the work” Most S indicate that they had previously seen: “John was using a hammer to fix the birdhouse when his father came out to watch him and help him do the work” Inference • One role of inference is to create connections between parts of a story • Coherence: representation of the text in one’s mind so that information from one part of the text can be related to information in another part of the text • Coherence can be created by difference types of inference – Anaphoric inferences: – Instrumental inferences: – Causal inferences: Inference • Anaphoric inferences: – Connecting objects/people in one sentence to objects/people in other sentences • Easy: «Riffifi the famous poodle won the dog show. She has now won the last three shows she has entered» Riffifi = She = Female dog • More difficult: «I take the kids and we fish. And then, of course we grill them fish (George Foreman) I and kids • Instrumental inferences: – Inferences about tools or methods (e.g. John’s hammer) • Causal inferences: – Events in one clause caused by events in previous sentence • Easy: «Sharon took an aspirin. Her headache went away.» • More difficult: «Sharon took a shower. Her headache went away.» Understanding Text and Stories • Situation model: mental representation of what a text is about – Represent events as if experiencing the situation – Point of view of protagonist – Does not consist of information about phrases, sentences, or paragraphs • Mental representations as simulations: we simulate the perceptual and motor characteristics of the objects and actions in a story Does the object mentioned in the sentence exist in the picture? He hammered the nail into the wall Faster RT Horizontal fit into the wall (Stanfield & Zwaan, 2001) Understanding Text and Stories The ranger saw the eagle in the sky because this one doesn’t look like it is in the sky Faster RT Results support the idea that S create perceptions that matched the situation as they were reading the sentences Producing Language: Conversations • The most common form of language production: conversations – Two or more people talking together – Dynamic and rapid – Involves shared knowledge – Need to take into account what the other person is saying – Also, what the other person knows about the topic • Given-new contract: speaker constructs sentences so they include – Given information: – information that the listener already knows – New information – New can then become given information Producing Speech: Conversations • Not following the given-new contract may result in ambiguities 1. We checked the picnic supplies. The beer was warm. It is ambiguous because we didn’t know beer was one of the supplies 2. We got some beer out of the trunk. The beer was warm. – Takes subjects longer to comprehend sentence pair that violates given-new contract – Needs to make an inference in one pair that is not necessary in the other one Producing Speech: Conversations • Given-new captures the collaborative nature of conversations • Common ground: the speakers’ mutual knowledge, beliefs, and assumptions – Each person needs to understand the knowledge that the other person brings to the conversation • How is common ground established? – Back and forth exchanges in the conversation • Example – Doctors assume that patients have limited knowledge of physiology and medical terminology • Usually say «heart attack» rather than «myocardial infarction» • If the patient is also doctor, they may switch terminology Producing Speech: Conversations • The coordination between speakers also includes using similar grammatical constructions • Syntactic coordination – Using similar grammatical constructions experiment • Syntactic priming – Production of a specific grammatical construction by one person increases chances other person will use that construction – It can lead people to coordinate the grammatical form of their statements ➔ Reduces computational load in conversation Producing Speech: Conversations In syntactic priming experiments: •Two people engage in a conversation about some task •The experimenter determines whether a specific grammatical construction used by one person causes the other person to use it Two ways say the same meaning different syntactic structure •One of the two S could be a confederate •The confederate could prime a construct so the ppt use the same form of syntactic structure • The girl gave the book to the boy • The girl gave the boy the book •The S picks a matching card •S describes the card to the other person Ended here 7/11 Producing Speech: Conversations • 78% of the trials, the form of S description matches the form of the confederate’s priming statement • Supports the idea that speakers are sensitive to the linguistic behavior of other speakers and adjust their behavior to match • Conversation: dynamic, rapid, common ground is established, syntactic forms are aligned – ➔ this reduces computational time involved in creating a conversation – Allows for understanding + production Culture, Language, & Cognition • Sapir-Whorf hypothesis: language influences thought • The nature of a culture’s language can affect the way people think (Whorf, 1956) • Winawer and coworkers (2007) – Two cultures had differences in how participants responded to blue squares based on how they were categorized 45 E Russian S responded more quickly when the bottom squares were from different categories E 17 - category Wh E 24 categories Music and Language • Similarities and differences: emotions - – Both can evoke emotions music & language – In music emotions are created through sounds without meaning – In language emotions are created through meaning and prosody • E.g., «I hate you» • Prosody in language: pattern of intonation and rhythm • Similarities and differences: creating sequences sequence otoa – Both combine elements to create structured sequences – In music sounds are combined based on their sounds – In language words are combined based on their meaning • Conclusion – Although there are important differences between music and language, there are similarities in many respects Music and Language • Broca’s aphasia Grammar – Patients with Broca’s aphasia perform poorly in syntactic language and music tasks Musical syntactic (harmonic) relations in sentences (Patel et al., 2008) • P600 effect in healthy participants - – Syntactic violation elicit a P600 effect in both language and music - (Patel et al., 1998) Some Questions to Consider • How do we understand individual words, and how are words combined to create sentences? • How can we understand sentences that have more than one meaning? • How do we understand stories? • Does language affect the way a person perceives colors?