Meaning acquisition - an der Universität Duisburg

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Universität Duisburg-Essen
Wintersemester 2006/07
PS/HS Language, meaning and use
Dozent: Prof. R. Hickey
Meaning acquisition
Anna Adaszynski, Hans-Joachim Faust,
Marius Finnern, Anastasia Nikolaeva,
Nicole Reif, Sarah Thiele
The Acquisition of Grammar
 Grammatical structure is specific to
language as a system of representation
and communication.
 The acquisition of grammar can not be
studied fruitfully without taking into
account cognitive development.
Cognitive Development
 All human beings are supposed to make
sense of the physical and social
environment they live in by universal
processes of reasoning in universal
structures of thought.
 Though speed and outcome may vary
according to socio-cultural factors,
processes and structures are
fundamentally the same.
 Humans make sense of the world of objects and
people, i.e. their reasoning patterns in systems of a
logic of actions and thinking, systems that can be
described as abstract structures.
 There are progressive changes in the relation
between the knowing subject and the object of his
knowledge though the construction of structural
fragments, then differentiations and integration into
increasingly varied and more powerful systems by
means of abstraction.
 Besides, the production and the comprehension of
utterances is interacting with many kinds of knowledge,
as well as with beliefs and emotions.
The Semantic Bootstrapping
Hypothesis (1)
 Definition: Semantic bootstrapping in linguistics
refers to the hypothesis that children utilize conceptual
knowledge to create grammatical categories when
acquiring their first language.
Thus, for example, categories like "type of
object/person" maps directly onto the linguistic
category "noun", category like "action" onto "verb",
etc. This will get children started on their way to
acquiring parts of speech, which later can be
supplemented by other linguistic information.
What does Steven Pinker think
of “semantic bootstrapping”?
 Grammitical entities do not have semantic
definition in adult grammars, but maybe in
parent-child discourse.
 When speaking to infants, parents refer to
people and physical objects using nouns,
they refer to physical actions using verbs and
so on. This also could help children to percept
grammatical relations: Physical object and
action instead of “nounhood” or “verbhood”.
 Pinker: The categorization of words can be
inferred from their semantic properties, and
their grammatical relations can be inferred from
the semantic relation in the event
witnessed.
 Grimshaw/Macnamara: Once a basis of
semantically induced rules is in place, the child
is able to learn the semantically neutral items
because of their appearance within the
structure of the sentence.
 Pinker and his Semantic Bootstrapping Hypothesis
do not claim that children allow semantically based
analyses to override distributional analysy.
 In fact the SBH claims that children have to give priority
to distributionally based analyses.
But how do they know which distributional contexts are
relevant?
Universal correlation
 Steven Pinker argues that there exist symbols with
universal properties and this hypothesis has to be
tanslated ino the fact that certain phenomena tend to
be correlated with one another across languages.
Example: the concept of “Subject”
a) the agentive argument of active action predicates
b) the nounphrase position that is usually the leftmost
nominal phrase daughter of S
c) the argument of an embedded complement that is
controlled by the matrix predicate
d) the function that objects assume during passivization
e) …
These rules are universal correlated. The symbols
labeled “Subject” are in some sense of the same
psychological kind.
The SBH amounts to the claim that
a) the child uses phenomenon
b) to label certain entities as “Subjects” in the
first rules he or she coins
c) he or she expects these entities in those rules
to enter phenomena
d) these entities are “Subjects” without further
learning
e) the child fixes the parameters of those
phenomena
 Pinker: The child is spared from having to
record all perceptible properties and
correlations involving the input elements. Just
exploitation of formal and substantive linguistic
univerals to focus on the learning process upon
those properties. (inductive)
 Chomsky: The child exploits the “rich
deductive structure” inherent in the family
resamblance correlation defining substantive
universals, and at the very start he or she uses
the semantically transparant members of the
family as the first “premises” of the duduction.

Other symbols
It is necessary to show that


the symbol enters into a set of phenomena
the phenomena must include some notion
which is available o the child
this notion has to be expressed in a question


If that is the case the SBH can be applied to
the problem of how rules incorporating that
symbol are first acquired: the child can use
the phenomenon that includes the
perceptually available notion as the inductive
basis for the symbol in question.
 Grimshaw: Linguists often use descreptive
ways of analysing he category membership of
a word, although they know that the formal way
is much better to do so. But in fact they use
semantic notions as their first hypothesis and
linguists seldom have to recategorize sets of
words after examining oher phenomena.
 Pinker: It is not unreasonable to assume that
also children can safely begin by categorizing
words in this way.
Implications for the Semantic
Bootstrapping Hypothesis (2)
 The Semantic bootstrapping hypothesis contains that children
utilize conceptual knowledge to create grammatical
categories when acquiring their first language.
 Thus, for example, categories like "type of object/person"
maps directly onto the linguistic category "noun", category like
"action" onto "verb", etc.
 This will get children started on their way to acquiring parts of
speech, which later can be supplemented by other linguistic
information.
 The hypothesis received some support from the experiments
that showed that three- to five-year-olds do, in fact, generally
use nouns for things and verbs for actions more often than
adults do.
 Syntactic bootstrapping and learning from distributional
patterns of the language have also been proposed as a way
for children to acquire word-classes.
 syntax is correlated with semantics but is not reducible
to semantics
 Question: How do children use perceptual input
(sounds and situations) to hypothesize grammatical
structures at the outset of the language acquisition
process?
 Suggestion:
 Children innately expect syntax and semantics as
correlated.
 they can derive the semantic representation by
nongrammatical means and can thereby do a
preliminary syntactic analysis of the first parental
utterances they process.
 with some grammatical rules, children are now able to
handle sentences violating these correlations between
syntax and semantics (passives, deverbal nouns),
because of their experiences in analysing.
 In situations where structures violate general rules
the child needs more information either from the
situational context or from the semantic knowledge.
 they become relaxed in the input speech they process.
 they can do this by classifying these words in terms of
their distribution within the grammatical structure.
 they can now analyse these structures.
 Semantic Bootstrapping Hypothesis can be
helpful in explaining how language acquisition
gets started.
 Problems:
 Assumption: Children can accurately encode the
meaning of a sentence an adult says.
 If the correlations between syntax and semantics
are not universal: How do children learn languages
that violate these correlations?
 If the correlations are only probabilistic, we need to
assume either, that parents filter the noncorrelated
structures (passives, deverbal nouns), or that
children can filter them using some independent
criterions.
Semantic bootstrapping
hypothesis

This figure shows
how the flow and
understanding of
information in the
language
acquisition process
is understood to
take place.
 Whereas the first picture
needs language input to
be modified to the child’s
understanding of the
situation, the 2nd figure
holds an explanation for
children understanding
sentences which are not
filtered for their
understanding (i. e.
leaving passives out). It
makes use of the
assumption that children
are capable of using
categories and labelling
for constructing meaning
and that they thus can
rely on acquired
structures to encode and
analyze utterances.
Learning by Instinct
 Lots of people think of instinct and learning
as two separate things and even
alternatives.
 Different studies have shown that this is not
right  There cannot be made a sharp
distinction between instinct and learning (in
human AND in animal behaviour!)
  Process of learning is often controlled
by instinct
“pre-programmed” genetically
 Learning by instinct appears at all
levels of mental complexity.
Ethnology and Behaviourist
Psychology
Ethnology:
 E. Is the study of instinct
 Most animal behaviour is controlled by four
basic factors:




Sign stimuli (instinctively recognized things)
Motor programs (innate responses to these things)
Drive (controlling motivational impulses)
Imprinting (a restricted and seemingly aberrant form
of learning)
Example:
 Geese build their nests on the ground. When one
goose knocks an egg out of her nest, a stereotype
and innate behaviour appears. The animal fixes its
eyes on the lost egg, stands up and rolls it back
where it belongs.
 Sign stimuli: Convex features that trigger the
behaviour
 Motor program: The egg rolling response
 Drive: The drive to protect its eggs appears two
weeks before the goose lays eggs and persists
two weeks after the eggs hatch.
 Imprinting: Goslings follow every object that
makes a “kum-kum” call
 Classical Conditioning:
 Ivan Pavlov
 Experiments with a dog
 Dog learned, that he got food, when a bell
rang
 Operant Conditioning:
 Animals learn as a result of trial-and-error
experimentation  they behave in a special
way because they want to obtain a reward or
avoid punishment.
Both positions (Ethnology and Behaviourist
Psychology ) cannot stand alone
 instinct and learning are strongly
connected
 Animals can make certain associations
easier or more difficult in different situations.
 They are innately influenced to learn
some things better than others.
Example:
 Rats easily learn to identify food that makes
them ill because of a smell, but not because
of visually or auditory cues.
An example of instinctive
learning: Bees
 Bees are collecting
nectar and pollen.
 Their instinct lets them
recognise flowerlike objects,
but they have to learn which of these objects
can give them food
 At first the bees learn the smell of flower, then
the colour and after that the shapes and colour
patterns.
 The bees prefer some smells, colours, shapes
and colour patterns.
 The bees have a hierarchical structure
in their mind.
 The smell is most important!
 Refers to the natural conditions: The
smell of a flower is nearly constant, the
colour or shape can change in different
light conditions.
 Another important organizational element
is the time of day each flower provides
nectar.
Conclusion
These facts show that honey bees learn
different things about flowers and store
them in a hierarchical order.
The things that they learn and the time they
need for it are innate characteristics.
Learning about Enemies
 Animals need to learn how to recognize and respond to
various kinds of predators and enemies
 Nesting birds for example must learn to distinguish
harmless birds from birds which hunt for eggs and
chicks
 When nesting birds detect nest predators, they attack
en masse.
→ this phenomenon is known as “mobbing”
 Birds need to learn whom to mob and whom to ignore
 This process of learning is innately guided
(1)Between the cages
there is a rotable, fourchambered box. Each
bird can see only one
chamber of the box,but it
can also see into the
other bird´s cage.
(2)Each bird is shown a
harmless species
without showing any
interest.
(3)A is shown a predator
and B is shown a
harmless one: A tries to
chase it away and gives
the characteristic
“mobbing call”.
(4)B watches A and then
joins in the mobbing
behavior.It has learned
to mob a harmless
species.
(5)When both birds are
shown the harmless bird
B teaches A to mob it as
well.
 → This aversion was
passed on from
generation to generation
Song Learning in Birds
 All birds have a repertoire of one or two
dozen calls that are innately produced
and recognized
 Several kinds of birds also have more
complex vocal patterns that must to
some extent be learned from adults of
the same species
Process of Song Learning
A bird kept in auditory isolation begins to
experiment with song notes by the time it is
about a month old
→ This period of experimentation is known as
subsong
→The chick is born with a basic innate song,
which it learns to elaborate when it raised in
the wild
 The time in which the drive to learn is high is
called the sensitive period ( before it is about 7
weeks old)
Speech Learning in Humans


Human infants innately recognize most
consonant sounds that are characteristic of
human speech, including consonants not
present in the language they normally hear
The innate ability to identify sign stimuli
present in consonants confers several
advantages:
1. It allows the infant to ignore a world full of irrelevant
auditory stimuli in order to focus on speech sounds.
2. It allows the infant to decode the many layers of meaning
in the complex and variable sound of speech
3. It provides an internal standard for the child to use in
judging and shaping speech sounds
Language and Experience
 To know a language is to know the relations
between sounds and their meanings
 These relations are acquired from specific
experience and some interpretive context,
paired with speech events
  Problem: The acquisition of language is
based on only partial and sometimes
impoverished relevant experience!
Problems from learning from
observation:
 Too many encodings:
When the mother points to a cat saying “cat”, the child might
relate the word “cat” with the meaning animal, fur, cute or tail.
 False experiences:
When a child is inspecting his mother stroking the cat and
talking of the grandmother’s visit at the same time, this might
create a false pairing.
 Abstract meanings:
Many words have no direct connection with sensoryperceptual experience (fun, good) or encode unobservable
relations (similar, brother), properties (very, the) or grammatical
functions (of, to).
Different experience, different
meanings?
 Experiments with blind children hint at
a different interpretation of the words
look and touch
 Look is more like “apprehend” or
“explore” to the blind child (manipulate,
feel all over)
 Touch is rather interpreted as “contact”
(bang, tap)
Responses of sighted, but
blindfolded children
 Touch is interpreted as simple manual
contact
 Look seems to be interpreted as
commands to do something visual (they
oriented their heads in the direction
indicated by the command)
Bibliography
 First Language Acquisition
The Essential Readings
Edited by Barbara C. Lust and Claire
Foley
2004
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