9/23 Language and Aphasia - Woodbury Flashcards
three basic steps of using language
slightly more complex steps of using language
- receive input
- process it
- respond
- distinguish speech from noise
- identify words
- attach meaning
- interpret overarchin message
a. formulate response
b. choose approp words
c. structure correctly
d. plan motor movements
e. deliver response
language localization
98% of people, language lateralized to left hemisphere
all people, language localized to perisylvian fissure area
however, language system extends throughout cortex (“language octopus”) → can get aphasia if you damage outside of the lang core
- see diff clinical presentation
language
aphasia
- definition
- primary cause
ability to understand spoken and written language
ability to produce spoken and written language
aphasia is partial/total loss of ability to articular ideas and comprehend spoken/written language resulting from damage to the brain (acquired deficit!!!)
- by definition, if you have aphasia, ALL ATTRIBUTES MUST BE COMPROMISED TO SOME EXTENT (not necessarily equally)
most aphasias are due to vascular accidents (often involving MCA)
aphasia decision tree
naming tests
- difficulty naming objects is an indicator of aphasia
- ability to name obj is the last attribute to recover
fluent vs nonfluent?
- fluent: fluid speech (not asuming content)
- nonfluent: relatively more difficulty with output
fluent vs nonfluent aphasia
locations
cause of aphasias/specific aphasia types
most aphasias occur due to vascular accidents often involving MCA
- non-fluent aphasia (Broca’s)
- frontal lobe/insula
- blockage of MCA superior division (insula/frontal)
- fluent aphasia (Wernicke’s)
- temporal/parietal lobe
- blocage of MCA inferior division (temporal)
global aphasia with blockage of MCA (M1)
types of aphasia : what’s affected → localization
global : input and output → temporal/frontal/insula
Broca : output → frontal/insula
- Big Broca’s: present like global - can’t understand, cant express! but input fx regained after a couple of days
- Little Broca’s: less severely affected - just can’t express
Wernicke : input → temporal
conduction : relatively intact input and output BUT connection between two sets is compromised
transcortical motor : output
- similar to Broca’s
transcortical sensory : input
- similar to Wernicke’s
how do you distinguish between Broca’s/Wernicke’s and transcortical_motor/transcortical_sensory?
Broca’s and transcortical motor : input OK, output not
Wernicke’s and transcortical sensory : input not, output OK
Broca’s/Wernicke’s → core is destroyed → repetition is lost
transcortical_motor/sensory → core intact → repetition intact
Broca’s area
Broca’s contributions
inferior frontal gyrus
- Brodmann’s area 44 (pars opercularis)
- Brodmann’s area 45 (pars triangularis)
Broca’s contributions
1. localization of function: frontal lobes (Broca’s area)
2. lateralization of function: L hemi is usually dominant
3. Broca’s aphasia: expressive (non-fluent) aphasia
- Broca’s myth is that Broca’s aphasia is always due to lesion in Broca’s area
- NOT TRUE!
Broca’s aphasia
little vs big
labored, halting speech
telegraphic
naming difficulty
paraphasic errors
comprehension relatively well preserved
Little Broca’s
- presents like Broca’s
- recover usually within a year
Big Broca’s
- presents like global → transitions into Broca’s
- life-long aphasia problems
Wernicke’s area
Wernicke’s aphasia
posterior region of secondary auditory cortex
- fluent and “highly talkative”
- comprehension very poor
- difficulty following commands
- speech unintellible
- word subs
- jargon
- unaware of deficits
conduction aphasia
whats intact?
whats not? why?
characteristic presentation
disrupts communication between Wernicke’s area, Broca’s area
- repetition ability compromised BUT W and B areas are undamaged
- comprehension mostly intact
- patient mostly fluent
so what IS affected?
- lang skills that rely on speed
- ability to self-correct sentences before speaking
^ both require bidrectional comm between Broca’s and Wernicke’s areas
“paraphasic loop”
- paraphasic error (sub of a repeated word) followed by multiple iterations until error corrected
- fluency for several words, then get stuck again
transcortical aphasias
due to damage in watershed areas outside of Perisylvian Language Area
- anterior cerebral artery (transcort motor?)
- posterior cerebral artery (transcort sens?)
transcortical motor : presents like Broca’s
transcortical sensory : presents like Wernicke’s
in both, perisylvian core spared → repetition spared!
what does the R hemisphere do?
involved in recognizing emotional content of speech
damage to Wernicke’s equivalent results in inability to recognize emotional content
ex. difficulty determining when being lied to
damage to Broca’s equivalent results in “prosody deficits” - no alteration of tone/speed/emotion of speech
ex. difficulty putting emotional content into speech
