Transcript Aphasia: Symptoms and Syndromes Ling 411 – 04

Ling 411 – 04
Aphasia:
Symptoms and Syndromes
Simple Functions / Complex Functions
A question came to me in class when you mentioned that
localization does not work for complex functions (e.g. rats
navigating mazes), because the brain can compensate with
other brain areas. It seems to me that "understanding speech“,
localized in Wernicke's area, is actually a pretty complex
process...how is simplicity/complexity determined?
This is a general question, but I'm interested in the implications
of this question to also the Broca's area and any other
relevant areas. Either a general explanation or a point in the
right direction to what sort of researchers work I want to look
at would be greatly appreciated.
Thanks!
Halle
Simple Functions / Complex Functions
Complex
function
Simple
function
Phonological Production / Speaking
 Speaking is a complex process
• Therefore, involves multiple areas
 Phonological production is a simple process
• Broca’s area
 together with parts of primary motor area
and subcortical areas
 Other processes in speaking
• (other than phonological production)
Phonological Recognition / Understanding
 Understanding speech is a complex process
• Therefore, involves multiple areas
 Phonological recognition is a simple process
• Wernicke’s area
 together with primary auditory area and
subcortical areas
 Other processes in understanding
• (other than phonological recognition)
Doubts about Wernicke’s Area
Steven Pinker:
Wernicke’s area …was once thought to underlie
language comprehension. But that would not explain
why the speech of these patients sounds so psychotic.
The Language Instinct (1994)
Friedemann Pulvermüller:
…patients with Wernicke’s aphasia have difficulty
speaking…. These deficits are typical…and cannot be
easily explained by assuming a selective lesion to a
center devoted to language comprehension.
The Neuroscience of Language (2002)
Erratic Speech in Wernicke’s Aphasia
“I feel very well. My hearing, writing been
doing well. Things that I couldn’t hear from.
In other words, I used to be able to work
cigarettes. I didn’t know how…. Chesterfeela,
for 20 years I can write it.”
From Harold Goodglass
Understanding Aphasia (1993)
Lessons from Carl Wernicke
Carl Wernicke:
Primary functions alone can be referred to specific
areas…. All processes which exceed these primary
functions…are dependent on the fiber bundles, that is,
association.
Aphasia Symptom Complex (1874)
Any higher psychic processes exceeding these primary
assumptions cannot be localized but rest on the mutual
interaction of these fundamental psychic elements
which mediate their manifold relations by means of the
association fibers.
Recent Works on Aphasia (1885-86)
Wernicke and Connectionism
Kandel, Schwarz, and Jessel:
“…Wernicke proposed (1876) that only the most basic
mental functions, those concerned with simple perceptual
and motor activities, are localized to single areas of the
cortex, and that more complex intellectual functions result
from interconnections between several functional sites. In
placing the principle of localized function within a
connectionist framework, Wernicke appreciated that
different components of a single behavior are processed in
different regions of the brain. He thus advanced the first
evidence for the idea of distributed processing, which is
now central to our understanding of brain function.”
Essentials of Neural Science and Behavior (1995:13)
Basic functions and complex functions
 Phonological recognition is a basic function
 It is located in Wernicke’s area
•
along with, perhaps, the area intermediate
between primary auditory area and W’s area
 Speaking is a complex function
• It is a cooperative effort of several areas,
•
including Broca’s area and Wernicke’s area
Phonological recognition is a necessary
component of speaking
Wernicke’s Area and Speaking
 Phonological images guide speech production
 Phonological recognition monitors production
 Compare..
• Painting without visual perception
• Playing a piano without auditory perception
 Conclusion: Of course phonological
recognition (i.e. Wernicke’s area) plays a
role in speech production
Pulvermüller’s Statement
…patients with Wernicke’s aphasia have difficulty
speaking…. These deficits are typical…and cannot be
easily explained by assuming a selective lesion to a
center devoted to language comprehension.
The Neuroscience of Language (2002)
Paraphrasing Pulvermüller
…patients with Wernicke’s aphasia have difficulty
speaking…. These deficits are typical…and cannot be
easily explained by assuming a selective lesion to a
center devoted to language comprehension.
The Neuroscience of Language (2002)
Altered quote:
…patients with damage to the occipital lobe have
difficulty drawing pictures…. These deficits are
typical…and cannot be easily explained by assuming
a selective lesion to a center devoted to visual
perception.
Aphasic Symptoms
Varieties of language deficits
Inferences from language deficits
Problems of interpretation
Some speech of a Broca aphasic
Examiner: What brought you to the hospital?
Patient: Yes ... Monday ... Dad, and Dad ... hospital, and
... Wednesday, Wednesday, nine o'clock and ...
Thursday, ten o'clock ... doctors, two, two ... doctors
and ... teeth, yah. And a doctor ... girl, and gums, and I
(Patient was trying to explain that his father had
brought him into the hospital on Wednesday to have
some work done on his teeth.)
Speech production: a complex process
 The motor realization of speech involves the
smooth coordination of a number of separate
neuromuscular systems
 Sensory feedback and monitoring enter this
process at many points
 Coordination
• Activity of different systems must be
coordinated
• Planning of neural activity has to precede lowlevel activation by varying amounts of time
• Lead time from neural activity to muscle
activity differs from system to system
(Goodglass, 62)
More, from a (different) Broca’s apasic
"Me ... build-ing ... chairs, no, no cab-in-ets.
One, saw ... then, cutting wood ... working ..."
Attempt to describe “cookie theft”
picture (Broca’s aphasic)
Cookie … Okay … the cookie jar … and the kid
is a … uh … stool … bump … the skool …
skool … uh … hurt … and girl … I don’t know
…
Goodglass 139
Agrammatism in Broca’s aphasia
Examiner: Can you tell me about why you came back to
the hospital?
Patient: Yes … eh … Monday … eh … dad … Peter Hogan
and dad .. hospital. Er … two … er … doctors … and … er
… thirty minutes … and … er … yes … hospital. And .. Er
… Wednesday … Wednesday. Nine o’clock. And … er …
Thursday, ten o’clock … doctors … two … two … doctors…
and … er… teeth … fine.
E: Not exactly your teeth … your gP: Gum … gum …
E: What did they do to them?
P: And er … doctor and girl … and er .. And er gum …
(Goodglass 105)
Some speech of a Wernicke aphasic
Examiner’s question: Who lives at home with you?
Patient: My wife, she goes her work to work on it
but her heffle is all about it.
On testing for comprehension of single words,
patient can point to only one of six objects that are
named for him. His attempts to write result in a
jargon similar to his speech.
Goodglass 2
Another Wernicke aphasic
Attempt to describe a picture showing a young woman
standing with books in her arms, portrayed in a farm scene
with family members engaged in farm labor:
“Well, all I know is, somebody is clipping the
kreples and some wha, someone here on the
kureping arm … why I don’t know.”
Examples of anomia
I gave him a … Oh God! I know it!
Why can’t I say it?
I lost my … I keep my money in it.
Some speech of a conduction aphasic
Patient: I came into the hospital for some
tecs ... Some secs … tesk … T E S … tests.
Goodglass 73
Paraphasia
 Verbal paraphasia
• Use of one word instead of the intended one
• Usually, same part of speech
 Phonemic paraphasia
• Unintended phonemes or sequences of
•
phonemes
“paker” for “paper”, “sisperos” for “rhinoceros”
 Neologistic paraphasia
• “tilto” for “table”
• See, my refkid is … are bad. Oh, my cathopes
noe too good. Well, my gupa wasn’t too good.
(85)
Examples from a picture-naming test
Patient
Target Word
Response
Mr. W.
(Broca)
stethoscope
asparagus
pinwheel
nozzle
telescope – not right
carrot – no
kite
hose – no
Father L.
seahorse
(Wernicke) globe
stethoscope
hourglass
mandarin
atlas
octopus – no*
it’s a weather
*A picture of an octopus had
been presented earlier in the test
(Goodglass 78)
Phonemic paraphasia in
a conduction aphasic
Target Word (picture)
Response__________
Dart
cart … part … chart
Broom
broo … croo … broom
Scroll
scrip… screl … scrit …
roll it up … sholl … scroll
Bench
fence … park bence … bench
Pinwheel
pan .. P E A … peanwheel …
pinwill … penwhale … pinfin …
no pinwheel
(Goodglass 88)
Perisylvian Aphasic Syndromes
The most common perisylvian aphasias
in order of frequency of occurrence
Broca Aphasia
2. Wernicke Aphasia
3. Conduction Aphasia
1.
Characteristics of Broca Aphasia








Non-fluent speech
Sparse verbal output
Poorly articulated
Consists of short phrases
Produced with effort
Mostly nouns and other content words
Deficiency or absence of inflectional affixes
Absent or deficient syntactic structure
Word classes in Broca aphasia
 Mostly nouns
 Some adjectives
 A few verbs
• Generally uninflected or in ‘-ing’
form
 Function words few or non-existent
Comprehension in Broca aphasia
 Generally good
 More or less impaired for syntactically
complex sentences
 Difficulty in comprehending the same words
that are omitted in speech production
• Also, difficulty with repetition of these words
 Difficulty understanding relational words
• E.g. bigger/smaller, up/down, within/without
Verbal short-term memory deficit
(in Broca aphasia)
 Patients can readily point to individual
objects or body parts named by the
examiner
 But when asked to point to the same items
in a specific sequence they often fail at
the level of only two or three items
Benson & Ardila 124
How to explain?
Subtypes of Broca aphasia
 Type I
• A.k.a. little Broca aphasia
• Milder defects
• Less extensive damage
• Better prognosis
 Type II
• Symptoms worse
• More extensive damage
 These are not distinct, but variations
• Two spans along a scale
Conduction Aphasia
 Originally postulated by Wernicke
 Good comprehension
 Poor repetition
• Many phonemic paraphasias
 Defective production
• Many phonemic paraphasias
 Different subtypes
• Different areas of damage
 5 to 10 percent of all aphasias
Pronunciation deficits
 Broca’s aphasia
• Correct phonemes, faulty articulation
• The problem is more phonetic than phonemic
 Conduction aphasia
• Correct articulatory realization of phonemes
• But incorrect phonemes
• The problem is phonemic, not phonetic
 I.e., phonemic paraphasia
 (B&A call it ‘literal paraphasia’)
How to explain?
Areas of damage in conduction aphasia
 Different areas for different subtypes
 Arcuate fasciculus
 Left parietal lobe
•
•
Goldstein: ‘central aphasia’
 Probably the supramarginal gyrus (?)
Lower postcentral gyrus
 Luria: ‘afferent motor aphasia’
 Insula
 More than one of these areas can be
damaged in individual cases
Coronal section,
showing Sylvian
fissure, insula,
etc.
end