Download Slides Ch 2 - Department of Linguistics and English Language

Chapter 2
The Brain
Ideas about brain parallel
ideas about machines

1500s: brain is hydraulic pump
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1900: brain is switchboard
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1950: brain is serial processing computer
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Present: brain is parallel processing computer
Neurons

Dendrites receive info from other neurons
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Axons pass info to other neurons
Synapses
Cocaine

Cocaine doesn't allow dopamine to be reabsorbed. It builds up
and produces pleasure.
LSD

Serotonin also passes between the synapses. LSD replaces it
because it is similar.
Ecstasy
Antidepressants

Antidepressants keep serotonin from being reabsorbed. Lack of
serotonin causes depression.
Neurons


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Are at rest until they receive neurotransmitters from other
neurons
Once they get enough they are activated
When activated, inhibitory neurons reduce activity in other
neurons

Excitatory neurons increase activity in other neurons

The strength of the connection between neurons varies
Learning

Neurons make new connections between each other
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The strength of the connections between neurons changes
Learning

Neurons make new connections between each other

The strength of the connections between neurons changes
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Does this really explain it?
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It is so complex we can't really understand it
Memory

Patterns of connections and strengths of connections encode
memory
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The same neuron may be involved in millions of memories.

Computers don't store things this way. They run out of memory
Mirror
Neurons

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Monkeys had electrode on neurons that control hand and mouth
movements
When monkeys moved mouth and hands the electrons fired
When monkeys watched person pick up food and eat, the same
neurons fired
Mirror Neurons
Mirror
Neurons


In fMRI studies a part of the brain that moves the hand show
activation when the hand is moved.
It also shows activation when watching someone else's hand
move
Mirror
Neurons

Speculation that people with autism have problems with mirror
neurons
Apraxia

Brain damage that affects area involved in muscle movement
Top down, bottom up


Top-down: information at higher levels influences processing at
lower levels (use past experience to discover pattern)
Bottom-up: lower levels of processing occur without help from
higher levels (use features and clues in stimulus to find pattern)
Top down, bottom up


Bottom up—looking at each word or sound in order to
understand language
Top-down—using context in order to understand what someone
is saying
–
Tip of tongue phenomenon
Same ambiguous symbol interpreted differently
What do you
see?
What are the
words?
EAT
 GOAT
 LIFE


Top down or bottom up?
Experiment

2 groups

One heard story about sailors
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The other hear story about violence
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They were asked to identify this word:
Experiment

2 groups

One heard story about sailors

The other hear story about violence

They were asked to identify this word:
ROPE

Top down or bottom up?
Experiment


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Words cut out of recorded conversation
They were presented individually to
people
Only 50% correctly identified
The same words were understood in
the conversation with no problem
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Miller & Isard1963
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Three types of sentence:

a)Semantically & syntactically OK strings:


b)Semantically anomalous, syntactically OK
strings:


Accidents carry honey between the house.
c)Syntactically anomalous strings:
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
Accidents kill motorists on the highways
Around accidents country honey the shoot.
Listeners had to identify a word masked by a hissing sound
(white noise)

Performance accuracy: (a) better than (b) better than (c)
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=> Top-down influence from the semantic level
Phoneme
Restoration


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Warren & Warren (1970)
One phoneme was obscured by a cough (‘*’); subjects , subjects
fill in the missing sound and are not aware of it.

It was found that the *eel was on the axle.
(wheel)

It was found that the *eel was on the shoe.
(heel)

It was found that the *eel was on the orange.
(peel)

It was found that the *eel was on the table.
(meal)
Top-down influence from the semantic level on sound
identification
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
fi yuo cna raed tihs, yuo hvae a sgtrane mnid too. Cna yuo
raed tihs? Olny 55 plepoe out of 100 can.
i cdnuolt blveiee taht I cluod aulaclty uesdnatnrd waht I was
rdanieg. The phaonmneal pweor of the hmuan mnid, aoccdrnig
to a rscheearch at Cmabrigde Uinervtisy, it dseno’t mtaetr in
waht oerdr the ltteres in a wrod are, the olny iproamtnt tihng is
taht the frsit and lsat ltteer be in the rghi t pclae. The rset can be
a taotl mses and you can sitll raed it whotuit a pboerlm. Tihs is
bcuseae the huamn mnid deos not raed ervey lteter by istlef, but
the wrod as a wlohe. Azanmig huh? yaeh and I awlyas tghuhot
slpeling was ipmorantt! if you can raed tihs forwrad it.
Mispronuncia
tion
Detection
Marslen-Wilson & Welsh (1978)
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(mispronunciation detection in a shadowing task)
–Listeners had to repeat back text with some mispronunciations
in it
–In a highly predictable context listeners were unlikely to repeat
a mispronounced sound as it was (rather they restored an
intended pronunciation)
Example

As rain from Hurricane Rita threatened to once again
flood the city, the Army Corps of Engimeers was
racing to patch New Orleans' fractured levee system
while residents were forced to decide yet again
whethel to stay or go. Forecasters said the storm that
swiped Florida on Tuesday could strengthen to a
Catedory 4 and hit Texas by the end of the week. But
a slight turn to the right was possible and engimeers
feared additioral rain could swamp the city's levees.
Language is
automatic

Say color of the word you see
Language is
automatic

Say color of the word you see
Table
Language is
automatic
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Say color of the word you see
Green
Language is
automatic
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StroopTest (discovered by John Ridley
Stroopin 1935)
Interpretation: the Stroop effect
emphasizes the interference that
automatic processing of words has on
the more mentally "effortful" task of just
naming the colors
Gender
Differences

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Males have larger brains (6-8% larger)
Females have greater cortical complexity in some areas of the
brain
Corpus callosum is larger in females

May help incorporate emotion and language
Gender
Differences
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Gray matter: information processing

White matter: information transfer (multitasking?)
Who is better
at L2?

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Payne et al. 2011 looked at gender differences but held the
following constant:

a. Age of acquisition
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b. Working memory capacity
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c. Number of L2 classes taken,
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d. English reading comprehension
Everyone took a Spanish comprehension test
Who is better
at L2?
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Results:
Women were better on L2 comprehension test than men—even
when all the above were held constant
Is language
innate?
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Linguists versus psychologists

Linguists (Chomsky) argued that there is a
language acquisition device (LAD) in the mind,
preprogrammed before birth to learn language,
that allows any human to learn a (native)
language with similar success

Psychologists said “prove it”

Linguists couldn’t
Linguists vs.
psychologists
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Psychologists say “language is like any other skill”
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Linguists say “language is special”
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Psychologists are looking for proof that differences in some skills
means better able to learn language
Linguists are trying to prove that other skills and language are
not linked.
So--Psychologists say things like memory influence the ability to
learn language.