Title: Language Processing
1Language Processing and Comprehension
- Revised for Syllabus of 2014
2Consider the following
- What is more complicated Language or
Mathematics?
3Consider 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?
4Now, 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?
5And 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
6- 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!
7Welcome to a world where a word is worth a
thousand pictures
- Welcome to the world of language!
8Topics 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
9Topics Covered
Reading
10Background
- 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.
11Background
- 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.
12Definition
- Psycholinguistics is an area that studies the
psychological processes involved in the use of
language - both production and comprehension
13Activity
- 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 !
14Background
- 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! ?
15Background
- 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!
16Background
- 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.
17Background
- 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!
18Language and Communication
19Language 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
20Language 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
21Language and Communication
- So what is language?
- Hockett (1960, 1961) - differences between
language and communication.
22Language and Communication
- Use of speech
- Arbitrary association
- Naming
- Semanticity
- Structure dependence
- Displacement
- Generativeness
- Expressive power
23Use 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
24Arbitrary 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
25Naming
- 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
26Semanticity
- Use of symbols (words) to identify everything
- Language depends heavily on this
- Semanticity is a critical feature of human
language
27Structure 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
28Displacement
- 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
29Generativeness
- 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
30- 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)
31Expressive 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.
32Expressive 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!
33Language 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
34Language 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
35Language 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
36Language 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.
37Language 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
38Summary
39Functions of Language
- Nature of Human of Language
40Functions 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.
41Functions 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
42Functions 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?
43Functions 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?
44Functions 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
45Definition
- Speech acts communicate the required or intended
action to the listener
46Summary
47(No Transcript)
48Structure of Human Language
49The Structure of Language
- Phonemes
- Phonology
- Morphemes
- Morphology
- Words
- Phrases
- Sentences
- Syntax or Constituent Structure rules that
govern organization of all the above!
50The Structure of Language
51The 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
52The 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!
53Definition
- The study of how language sounds are produced and
comprehended is Phonology - The study of how syllables are created and
comprehended is Morphology
54Definition
- 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
55Summary
56Constituent Structure
- Structure of Human Language
57Constituent 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.
58Constituent 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!
59Constituent 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)
60Nature of Constituents
Look at the following sentences and arrange them
into natural groups i.e., group together words
that seem to belong together
- The young woman carried the heavy painting
- The kind-hearted boy helped his new friend across
the pond - Students who remember well will be more active in
class
61Nature 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!
62Nature of Constituents
63Nature 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!
64Nature 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!
65Definition
- A constituent is a group of words, like phrases,
that can be combined meaningfully and that convey
a single idea in a sentence!
66Activity, 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!
67Constituents and Understanding
68Summary
69Structure of Human Language Strategies for
Identifying Constituents
70Strategies 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)
71Strategies 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
72Strategies 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)
73Strategies 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!
74Strategies 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)
75Definition
- 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
76Strategies 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.
77Strategies 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).
78Summary
79Structure of Human Language Transformational
Grammar
80Transformational 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.
81Transformational 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.
82Transformational 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!
83Transformational 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!
84Transformational 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
85Transformational Grammar
- For example they are cooking apples can be
written in two ways
86Transformational Grammar
87Transformational 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
88Transformational 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?
89Transformational 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
90Transformational 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
91Transformational 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
92Transformational 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.
93Transformational 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.
94Transformational 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.
95Definition
- 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
96Summary
97Language Comprehension Factors Affecting
Comprehension
98Factors 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
99Factors 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
100negatives
- 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.
101negatives
- 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.
102negatives
- 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
103negatives
- 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)
104Factors 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
105the 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
106the 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
107the 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
108Factors 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.
109ambiguity
- 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
110ambiguity
- 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
111ambiguity
- 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.
112ambiguity
- 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
113ambiguity
- 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)
114ambiguity
- 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
115ambiguity
- 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).
116ambiguity
- 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
117ambiguity
- 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.
118ambiguity
- So, much more research is required to determine
which approach is more accurate.
119Summary
120? That is all!?
121(No Transcript)