Language and brain development

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Transcript Language and brain development

Theories of first language acquisition
We are not born speaking!
Language must be acquired.
◦ Learning vs. acquisition
If we think of all that is entailed in knowing a
language, it seems quite a challenge.
Children do not learn a new language but
naturally acquire it through an innate
language device.
Learning vs. acquisition
Language is an innate faculty
We are born with a Language acquisition
device (LAD)
◦ A set of language learning (acquisition) tools
◦ All humans have a universal grammar (UG)
What evidence is there for innate knowledge of
certain basic language features present in all
human languages?
◦ All languages have:
A grammar
Basic word order
Nouns and verbs
Subjects and objects
Consonants and vowels
Most languages have a similar word order
SVO = The teacher gave a lecture
75% of the world languages use either SVO or
OSV very rare: Yoda (star Wars)
Strong with the force you are
Humans then learn to specialize this
“universal grammar” (UG) for the particulars
of their language.
Word order, syntactic rule preferences
Phonetic and phonological constraints
Semantic interpretations
Pragmatic ways to converse
 Evidence
for innateness of language?
 The biologist Eric Lenneberg defined a list of
characteristics that are typical of innate (preprogrammed) behaviors in animals.
Maturationally controlled, emerging before they
are critically needed
Do not appear as the result of a conscious
Do not appear due to a trigger from external
Are relatively unaffected by direct teaching and
intensive practice.
Follow a regular sequence of “milestones” in their
Generally observe a critical period for their
When is language necessary?
When do children usually begin
speaking/using language coherently?
Is this criterion met?
Does a child decide to consciously pursue
certain skills? (e.g., walking)
Do babies make a conscious decision to
start learning a language?
Is this criterion met?
What would prompt a child to take up
What would prompt a child to begin
Is this criterion met?
We CAN teach prescriptive rules of
language. But we’re not talking about that
We correct children’s errors sometimes.
Does it help?
◦ ‘”Yesterday I goed to my friend’s house’
In fact, “coaching” seems to hurt rather than
help language ability in children.
Is this criterion met?
In spite of different
backgrounds, different
locations, and different
upbringings, most children
follow the very same
milestones in acquiring
Is this criterion met?
What is a critical period?
For first language acquisition, there seems to be a
critical period of the first five years, during which
children must be exposed to rich input. There is
also a period, from about 10-16 years, when
acquisition is possible, but not native-like.
For SLA, the issue is more complicated… More on
that later.
Is this criterion met?
CPH: Proposed by Lenneberg
◦ This hypothesis states that there is only a small
window of time for a first language to be natively
◦ If a child is denied language input, she will not
acquire language
 Genie: a girl discovered at age 13 who had not
acquired her first language
If humans do have an LAD, it must be located
somewhere physically…
(Chomsky denies that it can be physically
found in the body)
Insights from Neurolinguistics
Brain and spinal cord constitute the central
nervous system (CNS)
◦ Purpose: Communication
Cellular unit of the nervous system: neurons
◦ CNS consists of about 12 billion neurons.
◦ Brain consists of about 10 billion neurons.
Brain stem is the control system
◦ Regulates breathing, muscle movement, sleep, body
temperature etc.
Phrenology (Gall, 1796)
Brain consists of two
◦ Right side controls left body
side and vice versa
◦ Dichotic listening tests
Hemispheres are
connected through
Corpus callosum
Language is a left
hemisphere phenomenon
Paul Broca (French surgeon and
◦ Research on brain damage
◦ Broca’s area
◦ Broca’s aphasia
Carl Wernicke (German physician)
◦ Confirmed theory of left hemisphere
◦ Wernicke’s area
◦ Wernicke’s aphasia
What language impairments are found in
Broca's aphasia?
Nonfluent, labored, and hesitant speech
absence of function words and inflectional
short utterances,
relatively intact comprehension,
awareness of deficit.
The language symptoms of Wernicke's
aphasia are complementary to those of
Broca's aphasia.
fluent but empty speech,
grammatical inflections, normal prosody
utterances of normal length
poor comprehension
unaware of deficit.
Goodglass, H., & Kaplan, E. (1983). Boston Diagnostic Aphasia Examination. (2nd ed.). Media, PA: Williams & Wilkins.
“Cookie jar…fall
er: “overflow?”] Yeah.”
Heny, Jeannine. “Brain and Language (Clark, 634-657).
Well, this is…mother is away here workingout
o’here to get her better, but when she’s
working, the two boys looking in the other
part. One their small tile into her time here.
She’s working another time because she’s
getting, too.”
Heny, Jeannine. “Brain and Language (Clark, 634-657).
Young man, both spoken and sign language:
◦ Accident and damage to brain
◦ Both spoken and sign languages are affected
Deaf-mute person, sign language:
◦ Stroke and damage to left-side of the brain
◦ Impairment in sign language
Language learning and brain development go
hand in hand.
Children need to be exposed to language
Brain is resilient:
Early damage can cause right hemisphere to
take over language control.
Explain how Genie’s language
development fits into the theories of
Lenneberg, Chomsky and brain
According to this text, what is the
strongest evidence supporting the
theory of a “critical period” for
language acquisition?
Was Genie’s early language
deprivation the ONLY factor that
contributed to her abnormal language
development? Explain what other
factor(s) might have been involved.