Language Processing

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Language Processing and Comprehension

• Revised for Syllabus of 2014

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Consider the following

• What is more complicated Language or
  Mathematics?

3
Consider this

• School children differ in their ability to master
  math and yet
• At an even earlier age (as toddlers and
  preschoolers), almost all children learn to
  speak!
• Does that mean Math is more complicated?

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Now, consider this

• An average computer today can perform the most
  complicated mathematical calculations with ease
  and yet
• Despite years of research, no computer has as yet
  learnt to speak! (i.e., use language in the
  same way that humans use it)!
• Does this mean language is more complicated?

5
And this

• To use math, you need to learn rules to solve a
  set of problems
• To use language, you need
• not to recognize a set of sentences, but rather
• to learn a set of rules for constructing and
  understanding novel sentences.
• Can you understand this

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• Subhash Chandra Bose invaded India with an army
  of purple gorillas in 2007, by flying over the
  Alps when the black mountains rose and broke
  their wings, and Bose and his army were forced to
  land in the snow, nursing their wings. But they
  were up in a thrice and once they crossed the
  green desert, they fought the pink elephants that
  were guarding the borders and took everyone
  captive till the Pakistani government paid a
  ransom of rotten tomatoes to set India free!

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Welcome to a world where a word is worth a
thousand pictures

• Welcome to the world of language!

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Topics Covered

• Part 1 Nature and Structure
• Nature of human language
• Structure of human language theory of
  constituent processing, Chomskys
  transformational grammar, word organization,
  factors affecting comprehension
• Part 2Language Comprehension
• Understanding spoken language processes
  involved in speech perception
• Reading Process, theories of word recognition,
  factors affecting reading comprehension

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Topics Covered
Reading
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Background

• The area of cognitive science that examines how
  people learn and use language to communicate
  ideas is called psycholinguists.
• Cognitive science itself is an interdisciplinary
  field that draws on research from psychology,
  computer science, neuroscience, philosophy,
  linguistics to name a few.

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Background

• Psycholinguistics is also interdisciplinary and
  draws from research in many areas but primarily
  in psychology and linguistics.
• Within Psychology, it draws from research in
  attention, perception, memory, thinking, etc
• In linguistics, it draws from research in
  phonology, morphology, syntax, semantics, etc
• It also draws from computer science and
  neuroscience.

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Definition

• Psycholinguistics is an area that studies the
  psychological processes involved in the use of
  language - both production and comprehension

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Activity

• Repeat after me Heads, shoulders, knees and
  toes!
• Tell me your mothers name!
• Who is sitting next to you?
• What colour is your footwear?
• Notice how easily you were able to understand my
  instructions and say what is in your mind !

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Background

• Language is used with little difficulty by
  everyone who learns it at an early age.
• Thus, language processing, comprehension, and
  production seem extremely simple.
• People are remarkably efficient in understanding
  and producing language
• However, though we use language with ease, it is
  one of the most complicated of cognitive
  phenomena! ?

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Background

• At the heart of psycholinguistics are two
  questions
• What knowledge of language is needed for us to
  use language (tactic i.e. knowing how to speak
  or explicit i.e., knowing what processes are
  involved in speech?) and
• What cognitive processes are involved in the
  everyday use of language
• We shall try to answer these questions in the
  next two units!

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Background

• Language appears to be universal across all human
  societies.
• In the 1970s, a stone age tribe, the Tasaday, was
  found in a remote part of the Philippines. The
  tribe had been removed from any contact with the
  rest of the world.
• Yet they spoke a language
• Moreover, others could learn their language, and
  they could learn other languages.

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Background

• So, it seems that despite the apparent diversity
  of human languages, all societies use language in
  similar ways, and any language can be learned by
  anybody.
• Therefore, there must be certain underlying
  similarities across all languages ever invented
  or yet to be invented!
• Deep freeze, Blazing, blue star for way out!

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Language and Communication

• Nature of Human Language

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Language and Communication

• Language is not communication
• Language is a tool
• Other modes of communication
• All species have forms of communicating
• Many systems are very elaborate

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Language and Communication

• Wolves - emotions - position of ears, lips, and
  tail
• Primates and cats -facial expressions - fear,
  aggressiveness
• Birds - songs - sexual readiness, possession of
  territory
• Honeybees - dance - direction, distance and
  quality of honey

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Language and Communication

• So what is language?
• Hockett (1960, 1961) - differences between
  language and communication.

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Language and Communication

• Use of speech
• Arbitrary association
• Naming
• Semanticity

• Structure dependence
• Displacement
• Generativeness
• Expressive power

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Use of Speech

• Not vocalizations, but speech
• Do species other than humans use speech?
• Does language really need speech?
• What about
• Braille
• Sign language
• So not a critical feature

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Arbitrary Association

• Human language involves arbitrary relations
  between words and what the words refer to
• Buffalo, Bu-fe-low
• Why not big-fellow, or marshmallow or owaka?
• A rose by any other name
• Some animal systems involve similar arbitrariness
  e.g., bird songs
• So, not a critical feature

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Naming

• Think of a friend
• Humans depend heavily on naming
• Almost as if to say if we can name something, we
  have understood it, as if a name conveys all
  there is to know about the object!
• Monkeys warning signs use similar naming, but
  range is limited
• Whether naming is critical or not is debated

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Semanticity

• Use of symbols (words) to identify everything
• Language depends heavily on this
• Semanticity is a critical feature of human
  language

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Structure Dependence

• ships works he with v/s he works with ships
• Some forms of animal communication follow
  sequence but it is merely that a sequence
• Human language depends highly on structure parts
  of speech
• Structure dependence is a critical feature

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Displacement

• Communicate events from the past as well as about
  the future
• when I grow big like you, you will become small
  like me and I will give you a bath
• Intentions and imaginations - Cheshire cats,
  walking and talking playing cards, a flood of
  tears
• Displacement is a critical feature

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Generativeness

• By reconstructing a finite set of basic units,
  new messages can be regularly and frequently
  constructed
• Generativeness is a definite critical feature
• I LOVE ONLY YOU
• See how this can change

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• I love only you
• (and none other)
• Only I love you
• (and no one else does)
• I only love you
• (and nothing more, so dont expect ever lasting
  commitment, love is not worth the bondage)
• I love you only
• (I will have to leave you anyway because I have
  to marry this other person, but dont worry, I
  will always love you)

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Expressive Power

• Communicate an amazing range of thoughts
• When I grow up, I will be a monster!
• Monkey rraup, ?? I see an eagle hey, there
  is danger about in the form of an eagle.
• But that is the limit of the communiqué.

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Expressive Power

• The monkeys communication system does not extend
  to other associations such as I dont see an
  eagle, or Thank heavens it wasnt an eagle or
  Good gracious, was that an eagle, it looked more
  like a pterodactyl, or are you afraid of
  eagles?, or That was some huge eagle that we
  saw yesterday wasnt it, or even I hope the
  eagle doesnt come this way tomorrow!

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Language and Communication

• Nor can the bee dance to talk about the lovely
  sights he saw in his search for nectar!
• Expressive power is a critical feature
• But EP is highly dependent on generativeness,
  thus in itself, so may not be such a critical
  feature - debated

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Language Acquisition Device

• Why cannot parrots, dolphins, etc use language?
• Chomsky and others language is species-specific
• Chomsky humans have an LAD which is lacking in
  other species other species can not be taught
  language

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Language Acquisition Device

• Keith and Cathy Hayes attempted to train a chimp
  name Vicki to pronounce English words in the
  1940s
• In the 1960s, David Premack developed and tried
  to teach Sarah (a chimp) an artificial language
  where coloured plastic shapes stood for words
  fixed on a magnetic board

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Language Acquisition Device

• Around the same time (1960s), Terrace used a
  chimp called Nim Chimpsky to learn American Sign
  Language (ASL)
• Beatrice and Allen Gardner tried to teach a chimp
  named Washoe to use ASL, also in the 1960s
• Savage-Rumbaugh (1994) taught a bonobo called
  Matata language using a lexigram, her son Kanzi
  actually learnt it.

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Language Acquisition Device

• But while the chimpanzees learning was certainly
  impressive, it in no way apes the speed or
  flexibility that human children exhibit while
  learning language.
• Moreover, there is no evidence that these chimps
  used anything like sentences.
• Thus, only humans are capable of language

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Summary
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Functions of Language

• Nature of Human of Language

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Functions of language

• Imagine a situation when language in any form was
  forbidden!
• Language is virtually an essential part of every
  social interaction.
• And since social interaction is the most common
  action in life, language is an essential part of
  life.

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Functions of language

• Usually, when we speak, we are also doing
  something.
• For e.g.,
• I bet India will come back with at least two
  golds this Olympics
• I will return that book tomorrow

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Functions of language?

• Speech acts (Austin, 1962 Searle, 1969).
• Three most common types of speech acts correspond
  to the three types of sentences
• declarative,
• question,
• Imperative?

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Functions of language

• Helsinki is the capital of Sweden.
• Do you think it will rain today?
• Give me that carton of grape juice!
• Sometimes, the boundaries are blurred and
  intended or required action determines the speech
  act (or type of sentence)
• Can you shut the door?

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Functions of language

• Whatever the purpose, speech acts almost always
  require that information be conveyed to the
  listener.
• good heavens, that is such a dusty table,
• oh dear, its time to feed the baby)
• So the essential function of language is that it
  be able to convey information

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Definition

• Speech acts communicate the required or intended
  action to the listener

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Summary
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(No Transcript)
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Structure of Human Language

• Language

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The Structure of Language

• Phonemes
• Phonology
• Morphemes
• Morphology
• Words
• Phrases
• Sentences

• Syntax or Constituent Structure rules that
  govern organization of all the above!

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The Structure of Language
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The Structure of Language

• But a sentence that is syntactically correct is
  not enough to make good conversation
• mangoes wishing tape
• It should be semantic convey meaning

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The Structure of Language

• Finally, a conversation is not merely an exchange
  of meaningful information.
• In fact, social rules dictate the type of
  conversations that may or may not take place.
• These are called pragmatics the social aspects
  of language that govern most social interactions!
• For e.g., you may not say will you shut up to
  your teacher, no matter how tired or bored you
  are!

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Definition

• The study of how language sounds are produced and
  comprehended is Phonology
• The study of how syllables are created and
  comprehended is Morphology

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Definition

• The study of how words are organized is Syntax
• The study of meaning of language is Semantics
• The study of the social rules that govern
  language is Pragmatics

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Summary
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Constituent Structure

• Structure of Human Language

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Constituent Structure

• As you read this sentence you must combine
  the various phonemes, morphemes, words, and
  phrases together, decode the meanings of each
  individual constituent, and the combinations,
  to understand what the sentence means.

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Constituent Structure...

• Understands sounds like m e t y o r
• Meaning of words like your, met, mother, mall,
  yesterday
• Meaning of the phrases and the meaning of the
  whole sentence.
• A lot of cognitive work?
• Yes, but your brain manages to decode in
  milliseconds!

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Constituent Structure

• A constituent is a phrase or basic unit of the
  sentence, usually containing more than one word,
  but less than an entire sentence.
• As a rough guide, a constituent is a group of
  words that can be replaced by a single word
  without a change in function and without doing
  violence to (without violating) the rest of the
  sentence (Clark Clark, 1977)

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Nature of Constituents
Look at the following sentences and arrange them
into natural groups i.e., group together words
that seem to belong together

1. The young woman carried the heavy painting
2. The kind-hearted boy helped his new friend across
   the pond
3. Students who remember well will be more active in
   class

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Nature of Constituents

• Now the sentence the young woman carried the
  heavy painting could be broken down into two
  major parts young woman and carried the
  painting.
• We could easily replace the constituent young
  woman with a single word and not change the
  meaning of the sentence replace with
  Mruganayani, teenager, student and the meaning
  would not change!

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Nature of Constituents
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Nature of Constituents

• But woman carried the is not a constituent
• Why do listeners or readers look at constituents?
• Meaning of the word depends on its position in
  the phrase!

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Nature of Constituents

• painting is both a noun and a verb Nina was
  painting the cow
• block
• We are one block away from our destination
• Anita stacked the last block in the tower
• It was the block in the road that made us use
  the goat path
• The location of the word determines its meaning!
  at least in Formal ENGLISH!

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Definition

• A constituent is a group of words, like phrases,
  that can be combined meaningfully and that convey
  a single idea in a sentence!

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Activity, Read the paragraph and recite it to me

• Winnie the pooh was sitting on the branch of an
  oak tree one morning when he heard a rumbling
  noise, and felt the branch go up and down.
  Really, it was distant thunder and a gust of
  wind, but Winnie the pooh thought it was
  something else. Help! Help! he cried, A
  hungry Heffalumps trying to rob my honey. Quick,
  somebody! Help me!

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Constituents and Understanding
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Summary
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Structure of Human Language Strategies for
Identifying Constituents
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Strategies for identifying constituents

• Kimball (1973) proposed that listeners have
  developed a variety of strategies for dividing
  sentences into constituents.
• One strategy concerns function words.
• Function words are words that are very important
  for the structure of a grammatical sentence
• (for example prepositions and conjunctions)

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Strategies for identifying constituents

• Kimball suggested that whenever listeners find a
  function word, they begin a new constituent
• Pushpa said that Amit went to the store
• Listeners would begin a new constituent when they
  hear the words that and to.
• Now, try with this sentence
• The dog and the cat slept on the sofa in the
  living room

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Strategies for identifying constituents

• Kimball proposed that listeners develop a second
  strategy to accompany the first
• As soon as a function word indicates the
  beginning of a constituent, the listeners search
  for content words.
• Content words are words that refer to persons,
  objects, and actions
• (for example nouns and verbs)

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Strategies for identifying constituents

• A function word such as in alerts the listener
  to search for a noun.
• The listener knows that a noun must come, no
  matter how many other words intervene
• In the deep, dark, long-forgotten, spooky
• You know that a noun must come eventually!

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Strategies for identifying constituents

• Clark and Clark (1977) point out other strategies
  such as the use of affixes.
• Affixes are word parts that indicate the part of
  speech of the word.
• (for example -er, -y, -ly, etc)
• -er are typically nouns (painter, writer)
• -y words are typically adjectives (pretty, nasty)
• -ly are typically adverbs (finally, quickly)

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Definition

• Function words are words that determine the
  structure of language, they have to do with the
  surface structure or syntaxContent words are
  words that convey the idea through language, they
  have to do with semantics or deep structure

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Strategies for identifying constituents

• Thus, Clark and Clark suggest that listeners use
  these word parts to identify parts of speech.
• Thus by knowing the parts of speech, listeners
  can identify constituents in terms of nouns,
  verbs and therefore noun phrases and verb phrases.

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Strategies for identifying constituents

• But these strategies are not fool proof they do
  not guarantee a solution and may also be
  misleading (clever, lonely, lily).
• But they usually allow us to understand a
  sentence correctly.
• That is why these strategies are called
  heuristics (rules of thumb used in solving
  problems).

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Summary
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Structure of Human Language Transformational
Grammar
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Transformational Grammar

• People usually think of a sentence as an orderly
  sequence of words.
• Noam Chomsky (1957, 1965) proposed that there is
  more to a sentence that meets the eye
• Chomsky argued that human language abilities
  could only be explained in terms of a complex
  system of rules and principles represented in the
  minds of the speakers.

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Transformational Grammar

• Chomsky devised a model of transformational
  grammar to convert underlying deep structure to
  surface structure of a sentence.
• Surface structure is represented by the words
  that are actually spoken or written.
• Deep structure is the underlying meaning of the
  sentence, something more abstract than the words
  themselves.

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Transformational Grammar

• Chomsky pointed out that two sentences may have
  very different surface structure, but very
  similar deep structureTrisha threw the
  ballThe ball was thrown by Trisha
• In the example, the surface structure is very
  different in both sentences none of the words
  occupy the same position and some words that
  appear in one sentence do not appear in the other
  one at all!

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Transformational Grammar

• And yet, the meaning of both sentences are
  identical the deep structure is the same.
• In contrast, two sentences may share the same
  surface structure, but very different deep
  structurePrabha is easy to pleasePrabha is
  eager to please
• The sentences differ by a single word and yet
  mean two different things entirely!

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Transformational Grammar

• Further, sentences can have identical surface
  structures but very different deep
  structuresThe shooting of the hunters was
  terribleThe lamb was too hot to eatThey are
  cooking apples
• One way of analysing the deep structure is to
  rewrite the sentence differently using rewrite
  rules

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Transformational Grammar

• For example they are cooking apples can be
  written in two ways

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Transformational Grammar
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Transformational Grammar

• Chomsky proposed that people understand sentences
  by transforming the surface into a basic deep
  structure or kernel form.
• They use transformational rules to convert
  surface structure to deep structure while
  understanding language.
• And they use transformational rules to convert
  deep structure to surface structure while
  producing language

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Transformational Grammar

• Chomskys ideas inspired many studies during the
  60s and 70s.
• Mehler (1963) found that people recalled kernel
  sentences such asthe biologist has made the
  discovery better than one such ashasnt the
  discovery been made by the biologist?

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Transformational Grammar

• The reason for this is that the first sentence
  does not require many transformations to be
  understood it is an active statement.
• However, the second statement is a negative,
  passive question and requires many
  transformations to be understood i.e., brought
  to the active statement form

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Transformational Grammar

• However some research has not been in favour of
  Chomskys theory.
• For e.g., a sentence such asthe cookies were
  smelled by John should be easier to understand
  (take lesser time to process and verify)
  thanthe cookies were smelled because the
  second sentence requires an additional
  transformation to drop the by John

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Transformational Grammar

• However, Slobin (1966) demonstrated that the
  second sentence took less time to verify!
• So, there are exceptions
• In general, psychologists support Chomskys
  notion of a distinction between surface and deep
  structure

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Transformational Grammar

• But the notion of a close correspondence between
  the number of transformations and psychological
  complexity has been met with scepticism
  (Prideaux, 1985 Tartter, 1986).
• In other words, just because a sentence requires
  more transformations does not mean it is more
  difficult to understand.

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Transformational Grammar

• Chomskys more recent theories place less
  emphasis on transformations and more on
  grammatical information contained in the
  individual words (Chomsky, 1973, 1981 Wasow,
  1989).
• For example, the word greet not only conveys
  information about the word but also specifies
  that the word must be followed by a noun.

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Transformational Grammar

• Defining the grammatical information is more
  useful in determining how the meaning is conveyed
  rather than by just determining the number of
  transformations that need to be made.
• In fact, various factors affect the understanding
  of a sentence and some of these are dealt with in
  the next session.

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Definition

• Transformational grammar is the process through
  which surface structure can be transformed to (or
  broken down into) deep structure and deep
  structure can be transformed to (or used to
  create) surface structure

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Summary
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Language Comprehension Factors Affecting
Comprehension
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Factors Affecting Comprehension

• Research on transformational grammar also sparked
  an interest in the factors that influence
  understanding of sentences.
• In general, certain types of sentences are more
  difficult to understand than others these
  include
• Sentences with negative
• Sentences that have a passive voice
• Sentences that are ambiguous
• We shall consider each of these in turn

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Factors Affecting Comprehension - Negatives

• Sentences that have negatives tend to be more
  difficult to comprehend.
• For instance, this sentence that appeared in a
  newspaper article would be very difficult to
  comprehendALBANY The Assembly yesterday
  overwhelmingly approved a state Equal Rights
  Amendment free of revisions intended to restrict
  its influence on a womans right to an abortion

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negatives

• The sentence contains many implied negatives.
• Sentences that have negative words (no, not) or
  has implied negative, always take more time to
  process than sentences that have affirmatives
  (Taylor Taylor, 1990)
• A classic study by Clark and Chase (1972) studied
  this phenomenon.

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negatives

• Participants were asked to verify sentences such
  as thisStar is above plus. OR Plus
  is not above star.
• In both cases, the statement is true, but
  participants responded more quickly and made
  fewer errors if the sentence was affirmative.

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negatives

• If a sentence with one negative can cause
  misinterpretation, what of sentences with two or
  three negatives such as thisFew people strongly
  deny that the world is not flat (Sherman, 1976)
• The sentence has three negatives and is almost
  incomprehensible.
• Understanding decreases as the number of
  negatives increase

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negatives

• Sherman (1976) presented participants with
  affirmative sentences and sentences with one,
  two, three, or four negatives.
• He found that people understood every one of the
  affirmative sentences (100 accuracy) while
  people understood only 51 of sentences with four
  negatives (slightly better than guessing 50)

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Factors Affecting Comprehension the passive
voice

• Chomsky pointed out that active and passive voice
  forms may differ in surface structure but have
  the same deep structure
• Active form is more basic and has very few words,
  but the passive form requires additional words.
• Moreover, the active form is used seven times
  more often than the passive form in English

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the passive voice

• Further, some passive forms sound awkwardthe
  movie was watched by us
• And there are no passive forms for certain
  wordsIshanvi is sleeping - convert that!
• Verbs such as sleep, resemble, be, and cost do
  not have passive forms

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the passive voice

• Hornby (1974) asked people to judge whether a
  picture correctly represented a sentence.
• People responded faster if the sentence was
  activethe girl is petting the catthan if it
  was passivethe cat is being petted by the girl

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the passive voice

• The active voice is definitely easier to
  understand
• Earlier, the passive voice was highly recommended
  for scientific writing. Fortunately now, the
  current style manuals of many publications (such
  as APA) recommend using the active voice

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Factors Affecting Comprehension ambiguity

• As we discussed earlier, ambiguous sentences are
  more difficult to understand
• There are three kinds of ambiguity and each has a
  different effect on understanding
• The first is lexical ambiguity a word has two
  meaningstime flies like an arrow,but fruit
  flies like a banana.

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ambiguity

• The sentence is difficult to understand because
  the word flies has two meanings.
• Many puns and riddles are based on lexical
  ambiguity
• A second type of ambiguity is surface structure
  ambiguity in which words can be grouped together
  in more than one way

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ambiguity

• The only ones who volunteered are a few
  incompetent people like Nitin and you
• In this sentence you can be competent or
  incompetent
• A third type is deep structure ambiguity in which
  the essential logical relations between phrases
  can be interpreted in two ways
• senator found drunk on Capitol steps

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ambiguity

• An ambiguous sentence is one with a single
  surface structure but two or more different deep
  structures.
• Foss (1970) asked people to listen to ambiguous
  and unambiguous sentences. At the same time,
  they performed an additional task pressing a
  button every time they heard the sound b in a
  sentence.

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ambiguity

• RTs were longer when the participants were
  listening to an ambiguous sentence than an
  unambiguous one.
• Foss reasoned that ambiguous sentences need more
  processing time and thus the capacity for other
  tasks is lesser
• Theorists disagree about how listeners process
  ambiguous material

113
ambiguity

• Some theorists favour the PDP and argue that when
  people encounter potential ambiguity, the
  activation builds up for all meanings of the
  ambiguous items
• The degree of activation depends on the frequency
  of the meanings and the context (Simpson, 1984
  Simpson Burgess, 1985)

114
ambiguity

• So in the example,
• Pat took the money to the bank
• All the different meanings of the word bank will
  be activated such as
• But financial institution will be more highly
  activated than the other meanings of bank such as
  blood bank, river bank, etc

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ambiguity

• However, other theorists argue that context
  constrains the meaning activation at the very
  beginning itself
• These theorists believe that only a single
  interpretation of the sentence that is most
  appropriate in the context will be activated
  (Glucksberg, 1986).

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ambiguity

• For instance, if the sentence
• Pat received his monthly salary and he wanted to
  keep it safe
• Preceded the sentence
• Pat took the money to the bank
• Then it is unlikely that the brain will waste
  time and energy in activating all the other
  meanings of the bank, when the meaning financial
  institution is obvious from the context

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ambiguity

• However, if the passage read
• Pat took the money to the bank. He believed in
  the fable and wanted to make his wish come true.
  He wanted to drop the three coins in the river,
  repeating Annes name each time. Then she would
  consent to marry him.
• The meaning of the word bank will remain
  ambiguous till the reader/ listener comes to the
  word river. In this event, obviously the PDP
  approach makes more sense.

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ambiguity

• So, much more research is required to determine
  which approach is more accurate.

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Summary
120
? That is all!?
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