week5_s08

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McGarrity
COM 374 Week 5 outline – Language and the brain
I.
II.
III.
IV.
V.
Double dissociation of language and intelligence (general cognitive abilities)
A. Good language, poor intelligence
i.
Christopher, autistic savant http://www.uga.edu/lsava/Smith/Smith.html
a. severely mentally disabled, autistic
b. can speak 15-20 language
ii. Crystal, Williams syndrome http://www.wsf.org/multimedia/friendlygenes.htm
a. significantly mentally disabled
b. has excellent (almost overdeveloped) language skills, unique vocabulary
B. Good intelligence, poor language
i.
Specific Language Impairment (SLI)
a. normally developing in all respects except language
b. slow progression through stages of acquisition, problems with inflections
ii. ‘KE’ family (FOXP2 gene)
a. Average IQ
b. poor articulation/pronunciation of speech, but not a motor problem
c. poor/incorrect inflections
iii. Aphasics (see below)
The Brain
A. Contralateral control: left hemisphere controls right side of body, right hemisphere
controls left side of body
B. Laterialization: the brain is asymmetrical such that each hemisphere is specialized for
certain cognitive functions
C. Left hemisphere:
i.
Analytical processing
ii. Speech sounds (language), mathematics, temporal relations, intellectual
reasoning
D. Right hemisphere:
i.
Holistic processing
ii. Nonspeech sounds, music, visuo-spatial relations, emotional responses
Split Brain patients
A. Corpus callosum is severed
B. Left and right hemispheres operate independently
C. Provides evidence for lateralization
D. ‘Pieces of Mind’ transcript: http://www.pbs.org/saf/transcripts/transcript703.htm
Aphasia
A. Any language deficit caused by damage to the brain
B. Almost always caused by left hemisphere damage
i.
Broca’s aphasia: labored, halting speech, word-finding problems, lack of
‘function’ words/inflections (‘agrammatic’), good comprehension
ii. Wernicke’s aphasia: speech is fluent, correct word order, use of function
words, lexical errors, nonsense words (‘neologisms’), circumlocutions, poor
comprehension
C. Double dissociation: comprehension and production of language
Aphasia in ASL signers
VI.
VII.
VIII.
IX.
A. Damage to left hemisphere: signing is affected as in spoken languages
i.
Broca’s: sign slowly, omit inflections; good comprehension
ii. Wernicke’s: sign fluently but confusingly, show comprehension problems
B. Damage to right hemisphere (‘left (hemispatial) neglect’): left side of body/visual
field is ignored or neglected; impaired spatial understanding and recognition/use of
facial expressions
i.
In ASL users, facial expressions and left-side signs/space can be recognized
and used just for signing ASL syntax
ii. Demonstrates abstractness of language and its independence from the
modality in which it is expressed
Language and thought
A. Some theories about the relationship
i.
Thought = Language
ii. Thought determines language
iii. Sapir-Whorf hypothesis
a. Language determines thought (strong version)
b. Language influences thought (weak version)
Thought = language
A. Philosophers: since animals can’t speak language, they lack consciousness
B. Aristotle: the deaf can’t speak, so they lack reason/can’t be educated
C. Evidence against:
i.
Animals can think (vervets)
ii. Babies can think (Mickey experiment)
iii. Deaf adults w/o language
iv.
Creative thought
Thought determines language
A. People have thoughts and then put them into words
B. Babies must develop cognitively before they can speak
C. Evidence against:
i.
Mental math in bilinguals
Sapir-Whorf hypothesis
A. Linguistic determinism (Language determines thought)
i.
Pro: Pirahã tribe in Brazil: lack of counting terms leads to inability to count
http://www.sciencemag.org/cgi/content/full/1094492/DC1
ii. Pro: ‘Doll w/ Marble experiment’
a. hearing kids and deaf kids of deaf parents perform correctly
b. deaf kids of hearing parents perform incorrectly
c. Conclusion: deaf kids of hearing parents lack the cognitive skill to do the
experiment due to lack of complex language
iii. Con:
a. Translation between languages
b. Neologisms
c. Intended meanings
d. Ambiguity
B. Linguistic relativity (Language influences thought)
i.
Pro:
a. Color terms: The way our language slices up the color spectrum influences
how we remember colors later
b. Spatial orientation in Australian langs.
Study questions:
What do sign languages and whistling languages like Silbo Gomero demonstrate about the
human language faculty?
What is your own view on the relationship between language and thought? Support your view
with relevant examples.
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