4 - Aphasia Syndromes Flashcards
In the connectionist model, what are the three layers of units?
Semantic features
Words
Phonemes
In the connectionist model, what does each word corresponds to?
A single unit in the word layer
In the connectionist model, what links words to their semantic features and phonemes?
Bidirectional Excitatory Connections
In the connectionist model, what is each word connected to?
(2)
Semantic features
Phonemes
In the connectionist models, what is lexical access achieved by?
Interactive Spreading Activation
In the connectionist model, when Semantic Units are ___________, this activation spreads throughout the ___________, and ultimately the sounds of the ___________ are retrieved.
Activated
Neural network
Intended words
What is the FIRST step in the connectionist model?
(4)
[Semantic Step/Lemma Selection]
Activation begins and spreads for a fixed amount of time
Bilateral Excitatory Connections activate all three network levels (phonemic: /k, a, t/; words: “cat”, semantic: “pet with claws, etc.”)
Semantic neighbors (“dog”) become activated due to shared semantic features
Phonemically similar words are activated due to shared phonemes (“mat,” “rat”)
(The word with the highest level of activation is from the most appropriate grammatical category)
What is the SECOND step in the connectionist model?
(4)
[Phonological Step/Phonological Encoding]
Chosen word from first step is activated
Activation Process becomes nonlinear allowing network to handle the arbitrary mapping between semantic features and phonemes
The phonemes with the highest activation are linked into slots in a phonological frame (number and kind of syllables, stress patterns)
This linking concludes phonological encoding.
When do errors in phonological encoding tend to occur?
What to these errors tend to result in?
Due to noise, one or more wrong phonemes are more active than those of selected word.
Typically results in nonword (e.g., “lat” for CAT) but can be form‐related words (e.g. “mat” or “sat” for CAT).
What are the five error patterns that can occur in the connectionist model?
Semantic (“dog”)
Formal (“mat,” “cap)
Mixed (“rat”)
Unrelated (“log”)
Nonword (“lat”)
What aphasia syndromes could appear from cortical damage?
(3)
Broca’s
Wernicke’s
Global
What aphasia syndromes could result from damage of an unknown origin?
Anomic
What aphasia syndromes could appear when there is damage to the fiber tracts?
(4)
Conduction
Transcortical motor
Transcortical sensory
Mixed Transcortical
What is the most frequently occurring aphasia?
Anomic
Besides Anomia, what other aphasia types are common?
Broca’s
Wernicke’s
Global
What type of aphasia account for 50% of cases admitted to acute stroke units?
(2)
Global
Nonclassified aphasias
When are Anomia, Brocas, Conduction, Wernickes, and Transcortical more frequent in patients?
When patients have single lesions
What are different names for Broca’s Aphasia?
(4)
Expressive Aphasia
Motor Aphasia
Anterior Aphasia
Non-fluent Aphasia
What are the characteristics of Broca’s Aphasia?
(5)
Non-fluent (Slow, laboriously and halting speech + frequent pausing between syllables, words)
Agrammatic output (telegraphic)
Comprehension relatively preserved (as opposed to expression)
Poor, nonfluent repetition
Preserved self monitoring
Why do patients with Broca’s Aphasia struggle with repetition?
Poor language and motor planning
How does Broca’s Aphasia affect writing?
(4)
Writing similar to verbal output
Agrammatic
Large letters
Function words are absent
In Broca’s Aphasia, what produces Chronic Agrammatic Aphasia?
(2)
Lesions in Broca’s areas that extend into anterior insula cortex + temporal and parietal regions
What is needed to produce Broca’s Aphasia?
Damage to deep regions
What is considered Little Broca’s?
Smaller lesions limited to Brodman Area 44 cause aphasia that resolves quickly
What is considered Big Broca’s?
Large lesions producing full-blown, complex Broca’s aphasia
What are different names for Wernicke’s Aphasia?
(4)
Sensory Aphasia
Receptive Aphasia
Posterior Aphasia
Fluent Aphasia
What are characteristics of Wernicke’s Aphasia?
(8)
Fluent (Smooth + effortress output, long + syntactical sentences, normal intonation and stress patterns)
Frequent paraphasia (Semantic, occasional phonemic)
Paragrammatism
Jargon (strings of neologism with connecting words)
Impaired repetition
Poor comprehension
Poor self-monitoring
Anosognosia (non-awareness of deficits)
Why do patients with Wernicke’s Aphasia struggle with repetition?
Comprehension deficits
How does Wernicke’s Aphasia affect writing?
(3)
Handwriting mirrors verbal output
Small Letters
Significant word errors
What are characteristics of Global Aphasia?
(4)
Severe impairments in all language functions
Difficulty with basic comprehension deficits
Some respond in conversation suggesting basic comprehension skills
Limited verbal output + some stereotypical output.
What causes Conduction Aphasia?
(2)
Lesions in upper temporal lobe, lower parietal lobe or insula
This damages the arcuate fasiculus but spares Broca’s and Wernicke’s.
What are characteristics of Conduction Aphasia?
(4)
Fluent verbal output with occasional verbal paraphasias
Grossly Impaired Repetition
Relatively preserved language comprehension
Poor oral reading
How does Conduction Aphasia affect writing?
Handwriting typically functional - can be variable
What causes Transcortical Aphasias?
(2)
Dominant hemisphere is damage but Broca’s and Wernicke’s areas are spared
Damage (hypoperfusion) to watershed region surrounding perisylvian region (isolates this region, usually due to severe narrowing of MCA)
What is the defining characteristic of transcortical aphasias?
Preserved repetition
What are the characteristics of transcortical motor aphasia?
(3)
[Damage to anterior superior frontal lobe of language dominant hemisphere]
Reduced speech output
Good Repetition (imp)
Good Auditory comprehension
What are the characteristics of Transcortical Sensory Aphasia?
(3)
[Posterior isolation syndrome - damage to high parietal lobe in dominant language hemisphere]
Poor comprehension (listening and reading)
Good repetition (imp)
Fluent, empty speech with paraphasia (Like Wernicke’s but with good repetition)
What are the characteristics of Mixed Transcortical Aphasia?
(3)
[Isolation of Broca’s, Wernicke’s and arcuate fasciculus from rest of the brain]
Good repetition (imp)
Profound impairment in all communicative areas (Global???)
Typically nonfluent
What are the characteristics of Anomic Aphasia?
(4)
Word retrieval in verbal output and writing are the only obvious symptoms
Fluent and grammatically correct spontaneous output
Unusual pausing and circumlocutions
Residual state of many aphasic syndrome AFTER time of improvement (imp)
What is fluency like for Broca Aphasia?
Comprehension?
Repetition?
Poor
Intact words and simple sentences
Poor, Nonfluent
What is fluency like for Wernicke Aphasia?
Comprehension?
Repetition?
Good
Poor
Poor, fluent jargon
What is fluency like for Conduction Aphasia?
Comprehension?
Repetition?
Fair-good
Intact words and simple sentences
Poor
What is fluency like for TCM Aphasia?
Comprehension?
Repetition?
Poor
Intact words and simple sentences
Good
What is fluency like for TCS Aphasia?
Comprehension?
Repetition?
Good
Poor
Good
What is fluency like for Anomic Aphasia?
Comprehension?
Repetition?
Good
Good
Good
What are the Aphasia taxonomies?
(4)
Traditional Syndrome Classification
Fluent Vs. Non-fluent
Expressive Vs. Receptive
Intentional (non-fluent) Vs. Attentional (fluent
Most of the tasks performed poorly by patients with Non-Thalamic Subcortical (NS) Lesions appear to involve some degree of ____________-___________ flexibility in dealing with _______ __________, devising __________ _______________, and organizing and monitoring responses.
Cogntive-linguistic
Novel situations
Linguistic strategies
When there is a stroke in the Basal Ganglia, language issues probably stem from what?
A combination of damage resulting from the stroke and hyperfusion affecting language issues.
Language deficits in Non-Thalamic Subcortical (NS) Lesions resemble what?
A frontal-type language disorder
Thalamic Aphasia most frequently found in lesions to dominant what?
Tuberothalamic and paramedian arteries
In Thalamic Aphasia, why is there a low probability of associated cortical dysfunction?
They are small arteries
What are disorders are associated with Thalamic Aphasia?
(4)
Nuclei specific
Dysfluency and conditions similiar to transcortical aphasias
Arousal disturbances
Comprehension deficits
What do we call Alexia with Agraphia?
Pareto-Temporal Alexia
What are the characteristics of Pareto-Temporal Alexia?
(4)
Oral reading grossly impaired
Cannot identify words spelled out by the examiner
Copying printing material is better than writing to dictation
Common component of aphasia syndromes and rare in isolation
What kind of profile are you likely to have when there is damage to the basal ganglia?
Atypical profile
What is alexia?
Decline in reading ability
What is agraphia?
Decline in writing ability
What do we call Alexia without Agraphia?
Occipital Alexia
What is an another name for Occipital Alexia?
Pure Word Blindness
What are characteristics of Occipital Alexia/Pure Word Blindness?
(3)
Ability to write complex sentences or narratives without ability to read what they have written
May retain the ability to identify familiar words
Difficulty copying material
What type of lesions frequently cause Apraxia to accompany Aphasia?
(2)
Frontal lobe lesions
Anterior parietal lobe lesions
What are the two types of Apraxia which may accompany Aphasia?
Ideational Apraxia
Ideomotor Apraxia
What is Ideational Apraxia?
Inability to Conceptualize, Plan, and Execute the complex sequence of motor actions involving the use of tools or objects in everyday life.
What is Ideomotor Apraxia?
Inability to correctly imitate hand gestures and voluntarily mime tool/object use.
What must you consider before diagnosing Ideomotor Apraxia?
(4)
Paralysis
Weakness
Incoordination
Poor comprehension
What is the Pseudobulbar Affect?
(2)
Neurologic disorder characterized by involuntary, severe emotional displays
Usually uncontrollable crying and/or laughing
