Aphasia Classification Flashcards
What are the four models of language?
neuropsychological model
computational model
contemporary neurobiological modals
connectionist model (classification systems)
What model is most frequently used today and across the world?
Classical associative connectionist
(connectionist model)
the classical associative connectionist model is a paradigm that assumes the existence of language centers located in discrete regions of the brain:
Wernicke’s area (posterior center) and Broca’s area (anterior center)
Wernicke’s area (posterior center):
holds auditory language representation
a lesion in this center impairs auditory comprehension and influences speech production
Broca’s area (anterior center):
holds speech motor representations
a lesion in this center disrupts spoken word production, but leaves auditory comprehension intact (just a theory) - impacts the way they are talking, planning, and programming issues
a lesion/disruption of the arcuate fasciculus connecting posterior and anterior language centers is assumed to cause:
auditory repetition deficits (e.g., conduction aphasia)
The classical associative connectionist model has been influential in both neurological aphasiology and clinical aphasiology despite considerable criticism on _______ and _______ grounds.
linguistic and anatomical
No fluency, no comprehension, no repetition =
global aphasia
No fluency, has comprehension, has repetition =
(no, yes, yes)
transcortical motor aphasia
No fluency, has comprehension, no repetition =
(no, yes, no)
Broca’s aphasia
No fluency, has comprehension, has repetition =
(no, yes, yes)
Transcortical motor aphasia
Fluent, no comprehension, no repetition =
(yes, no, no)
Wernicke’s aphasia
Fluent, no comprehension, repetitive =
(yes, no, yes)
Transcortical sensory aphasia
Fluent, has comprehension, no repetition =
(yes, yes, no)
Conduction aphasia
Fluent, has comprehension, repetitive =
Anomic aphasia
The key limitation of the dominant connectionist paradigm:
Only about 30% of aphasic individuals fit neatly into these categories
There is some predictability of certain ______/________ functions and their association regions of the brain.
speech/language
But, there are problems with categorization:
different people use different classification systems
it’s hard to fit many patients into one category
“The term aphasia applies to _______-_______ ________ - not to the anatomy, physiology, or cognitive mechanism.
language-specific behaviors
Cognitive Neuropsychological Model
Language is no longer understood in terms of anatomical functions but instead as several identifiable processing components leading to the end point = word production
Cognitive Neuropsychological Model:
The study of individuals with brain injury can inform our understanding of:
normal language processes
Cognitive Neuropsychological Model:
Brain damage can disrupt a model or processing component selectively, leaving other components to operate:
normally
Cognitive Neuropsychological Model:
Provide a framework for:
assessment and treatment
study Cognitive Neuropsychological Model
Computational Models
Holds that various aspects of language can be represented as patterns of activity over interconnected sets of simple neuronlike processing units that occur in a competitive and cooperative fashion.
Computational Model:
Patterns of activity within this architecture are enabled through differentially weighted ____________ between _____.
connections between units
Computational Model:
a word is linked to specific processing _________
unit/node
Computational Model:
have been used to model:
aphasic errors (e.g., paraphasias)
Study computation model (dell’s spreading activation model of speech production)
Contemporary Neurobiological Models of Language
the brain works more like a dynamic network with plasticity
Contemporary Neurobiological Models of Language:
Gray and white matter are:
part of the same interactive process; (cortices and white matter as a network)
Contemporary Neurobiological Models of Language:
Dual Stream Model has 2 major pathways
dorsal stream and ventral stream
Contemporary Neurobiological Models of Language:
dorsal stream:
supported mainly by the superior longitudinal fasciculus and arcuate fasiculus
is associated with phonological processing
Contemporary Neurobiological Models of Language:
ventral stream:
supported mainly by the inferior fronto-occipital fasiculus
is associated with semantic processing
Contemporary Neurobiological Models of Language:
FAT (Frontal Aslant Tract)
connecting the supplementary motor area to the Broca’s area
plays a role in driving and initiating speech
the connectionist classification system was adopted by…
aphasia diagnostic standardized batteries (e.g., Boston Diagnostic Aphasia Examination; Western Aphasia Battery)
the connectionist classification system is commonly used by…
professionals serving patients with aphasia
the connectionist classification system is termed “connectionist” model because of…
the inherent assumption that the various aphasic subtypes reflect disruption of specific brain centers or the connections between these centers
(Broca’s, Wernicke’s, Conduction, Global, Transcortical Sensory, Transcortical Motor, Transcortical Mixed/Isolation)
a brain lesion in the anterior/frontal lobe region:
nonfluent, expressive aphasia
a brain lesion in the posterior region:
fluent, receptive aphasia
Fluent speech:
- relatively well- preserved fluency (speech is abundant - are talking and using long sentences, verbal output range of 100-200 words per minute, normal phrase length of 5 to 8 words per minute)
- no trouble with grammar
- precise articulation
- normal prosody
- normal auditory comprehension
- meaningless words
Non-fluent speech:
- excessive slow rate of speech
- speaking effort, halting, struggle, facial grimaces, and hand gestures
- limited phrase length (4 or fewer words per phrase, telegraphic speech, speak in short chunks)
- abnormal prosody, lack of intonation and rhythm, monotonous or choppy speech
- difficulty initiating speech
- grammatical problems
patients with aphasia have also been classified according to degree of comprehension deficit:
receptive aphasia and expressive aphasia
receptive (Wernicke’s) aphasia
- used to describe the language characteristics of significantly impaired auditory comprehension and reading comprehension
- when someone is able to speak well and use long sentences, but what they say may not make sense
expressive (Broca’s) aphasia:
- denotes relatively spared language comprehension but compromised language output abilities
- is difficult to produce speech
Fluent aphasias:
- Wernicke’s aphasia
- Conduction aphasia
- Anomic aphasia
- Transcortical Sensory aphasia
Non-fluent aphasias:
- Broca’s aphasia
- Global aphasia
- Transcortical Motor aphasia
- Transcortical Mixed or Isolation aphasia
Is Wernicke’s aphasia fluent or non-fluent?
Fluent
What regions of the brain are affected if there is a lesion to Wernicke’s area?
usually left posterior and temporal lobe - often extending up into parietal lobe
Is auditory comprehension good or impaired with Wernicke’s aphasia?
impaired/poor auditory comprehension
Does Wernicke’s aphasia have poor or good word finding/retrieval skills?
poor word finding/word retrieval (“empty speech”)
- naming and repetition impaired
- speech may be filled up with general/filler words (“this,” “that,” “stuff,” “thing”)
Good or impaired repetition skills in Wernicke’s aphasia?
impaired repetition skills
What is meant by fluent speech in Wernicke’s aphasia?
Little meaning conveyed
(paraphasiaas, neologistic jargon, relative lack of awareness of errors)
Wernicke’s aphasia characteristics:
Paraphasias (substitutions, unintended utterances)
- Verbal/non-semantic:unrelated word substitutions (pencil/dog)
- Semantic: related word substitution (cat/dog)
- Phonemic/literal: sound substitution (pog/dog, log/dog)
Wernicke’s aphasia characteristics:
Jargon (utterances don’t make sense)
- Extended English jargon
- Neologistic jargon (not real English words) - Neologisms (make up a word that has no meaning)
Wernicke’s aphasia characteristics:
Logorrhea or press of speech
- abnormal speech fluency (excessive speech output)
- rapid rate of speech
more Wernicke’s aphasia characteristics:
- normal prosodic and generally intact grammatical forms
- impaired reading comprehension and writing skills
- perseverations
other characteristics of Wernicke’s aphasia:
- normal articulation (no AOS present)
- turn taking problems
- difficulty maintaining topic
- lack of insight into their disability (not fully aware)
- lack of frustration in failed to communicate
- not hemiplegic
Is conduction aphasia fluent or non-fluent?
Fluent
Lesions to what area of the brain cause conduction aphasia?
lesion to lower parietal lobe
involves arcuate fasciculus, supramarginal gyrus, or small part of Wernicke’s area
The hallmark of conduction aphasia is the:
inability to repeat or imitate speech
Conduction aphasia:
is auditory comprehension good or impaired?
auditory comprehension is impaired, but often only mildly (better recognition of errors/better self-monitoring, self-corrections)
Characteristics of conduction aphasia:
- word finding/naming problems
- inability to repeat or imitate speech
- impaired auditory comprehension
- paraphasias
Conduction aphasia:
Paraphasias
- predominantly “phonemic” type
- semantic and verbal paraphasias as well as neologisms may be present but they are less frequent or rare
Conduction aphasia:
Many patients have good ______ length, ______, and ______ of language.
phrase, syntax, prosody
Conduction aphasia:
problems with reading and writing?
variable
Lesions to what area of the brain cause anomic aphasia?
lesion to angular gyrus area or lower temporal lobe
Anomic aphasia:
What is the most common and recognized symptom of anomic aphasia?
word retrieval problems during spontaneous speech and difficulty naming when asked to name pictures or objects
Anomic aphasia characteristics:
- better auditory comprehension
- thought formulation difficulties (struggle with train of thought)
- repetition is usually intact or just mildly impaired
- syntax is OK and normal articulation
- normal or near normal oral reading and writing
- paraphasias (verbal is more common)
Lesions to what area of the brain cause transcortical sensory aphasia?
lesions to regions more posterior to Wernicke’s area, involving the angular gyrus
does Transcortical Sensory Aphasia have good or bad repetition skills?
good repetition skills
Transcortical Sensory Aphasia characteristics:
All characteristics of Wernicke’s aphasia but good repetition skills
Transcortical Sensory Aphasia characteristics:
- impaired/poor auditory comprehension
- poor word finding/word retrieval (“empty speech”)
- fluent speech (paraphasias, neologistic jargon, relative lack of awareness of errors)
- paraphasias: substitutions, unintended utterances (verbal/non-semantic, semantic, phonemic/literal)
- jargon
- logorrhea or press of speech
Transcortical Sensory Aphasia characteristics:
- normal prosodic and and generally intact grammatical forms
- impaired reading comprehension and writing skills
- perseverations
- normal articulation (no AOS present)
- turn taking problems
- difficulty maintaining topic
- lack of insight into their disability (not fully aware)
- lack of frustration in failed to communicate
- not hemiplegic
Non-Fluent Aphasias:
- Broca’s
- Global
- Transcortical motor
- Mixed Transcortical/Isolation Syndrome
