5. Broca’s aphasia = expressive aphasia
Paul Broca
•Agrammatic speech/writing
•One word at a time
•Able to comprehend
6. Brain Mechanisms and Language
Implications for Normal Language Processing
Stimuli
Visual Input Visual region Wernicke’s Arcuate
Broca’s area
of the brain area fasciculus
Somasentory Wernicke’s Arcuate
Tactile input region Broca’s area
area fasciculus
of the brain
Auditory Input Auditory region Wernicke’s Arcuate
Broca’s area
of the brain area fasciculus
7.
8. Broca’s aphasia = lack of production
Wernicke’s aphasia = lack of comprehension
Conduction aphasia = no relation between both processes
Caramazza and Zurif (1976) Broca’s
area may
(1) The book that the girl is reading is yellow.
be
necessary
(2) The horse that the bear is kicking is brown. for syntax
Broca’s Linebarger, Schwartz and Safran (1983)
aphasics may
be able to
construct (3) How many did you see birds in the park?
syntactic
representations (4) The little boy fell down, didn’t it?
but fail to use
them
9. Lateralization of Language Processes
Split-Brain Research
- Severed corpus callosum
- No communication between hemispheres
Preventing epilepsy
What is perceived with the left visual fields goes to the right
hemisphere and viceversa.
10. Lateralization of Language Processes
Lateralization in Normal Brains
The visual field task
The dichotic listening task Different stimuli for
Broadbent (1954)
each ear
Showed
Left
Input Right ear Input
hemisphere
Right
hemisphere
11. The dichotic listening task Different stimuli for
each ear
Normal
Brains
Contralateral are stronger than Ipsalateral
pathways pathways
The dichotic listening task
Split
Brains
Speech
Left ear Right ear
Stimuli
12. failed The contralateral pathway is not
Left ear helpful – no corpus callosum
because
The ipsalateral pathway is
blocked by the contralateral
pathway.
Wood (1975)
Non-linguistic task
linguistic task
Greater right
Greater left hemisphere activity
hemisphere activity
13. Lateralization of Language Processes
Left Hemisphere Right Hemisphere
•Better appretiation of
pragmatic aspects
oSarcasm
oWhite lies
oHumor
•Alternative meanings last
longer