Announcements
NO SECTIONS TOMORROW, 11/11:
Veterans’ Day
But….
CLUE Session takes place as usual (11/11)
@ 6:30p-8:00p in MGH 278
LING 200 -- McGarrity
1
Today
Intro to Neurolinguistics
Language and the brain
Aphasia
Readings: 9.0 – 9.2
LING 200 -- McGarrity
2
What is Neurolinguistics?
The study of language and the brain
Seeks to understand the physical bases
of language storage and processing using
experimental methods
LING 200 -- McGarrity
3
The Brain
Divided into two
hemispheres: the left
and right hemispheres
Front
Left
hemi
Right
hemi
The hemispheres are
connected by bundle of
nerve fibers: the corpus
callosum
Corpus
callosum
4
The Brain
Contralateral control:
Each hemisphere
controls opposite side of
body
Left hemisphere
controls right side of body
Right hemisphere
controls left side of body
LING 200 -- McGarrity
5
The Brain
Lateralization: the brain is asymmetrical
such that each hemisphere is specialized
for certain cognitive functions
LING 200 -- McGarrity
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Lateralization
Left hemisphere:
Analytical processing (analyzing information)
Language, speech sounds
Mathematics
Temporal relations
Intellectual reasoning
LING 200 -- McGarrity
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Lateralization
Right hemisphere:
Holistic processing (recognizing overall
patterns, e.g., face recognition)
Nonspeech sounds
Music (in musically naïve individuals)
Visual-spatial skills
Emotional reactions
LING 200 -- McGarrity
8
How do we know this?
Medical and Experimental evidence
LING 200 -- McGarrity
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Evidence for Lateralization
Split-Brain patients:
Corpus callosum is surgically severed
Two hemispheres cannot communicate
with each other; act independently
Video clip from "Pieces of Mind: The Man with Two Brains“
Transcript available at:
http://www.pbs.org/saf/transcripts/transcript703.htm
LING 200 -- McGarrity
10
Split-Brain patients
Left
Hemisphere
“fruit”
Right
Hemisphere
“face”
corpus
callosum
Left
Eye
Right
Eye
LING 200 -- McGarrity
11
Left hemisphere: Language
Aphasia:
Any language deficit caused by damage to
the brain (e.g., bullet, stroke, infection, etc.)
Aphasia almost always caused by left
hemisphere damage
LING 200 -- McGarrity
12
Left hemisphere
Front
Broca’s area
Wernicke’s area
LING 200 -- McGarrity
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Left hemisphere: Language
Broca’s area:
organizes articulatory patterns of language;
also controls use of inflectional, function
morphemes
Wernicke’s area:
involved in comprehension and selection of
words from mental lexicon
Arcuate fasciculus:
connects Broca’s and Wernicke’s areas
LING 200 -- McGarrity
14
Broca’s aphasia
Labored, halting speech
Lack of inflections and function morphemes
Comprehension is generally good
LING 200 -- McGarrity
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Broca’s aphasia
LING 200 -- McGarrity
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(asked to describe picture)
“Cookie jar… over … chair… water…
empty…ov…ov…[Examiner: ‘overflow’?]
Yeah.”
LING 200 -- McGarrity
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Wernicke’s aphasia
Speech is fluent (i.e., can use function
words, inflections) but semantically
incoherent
Lexical errors, nonsense words,
circumlocutions
Comprehension is poor
LING 200 -- McGarrity
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