Concept and History of CAPD Flashcards
Where is the primary auditory area?
Heschel’s gyrus located in the sylvian fissure and posterior 1/3 of the superior temporal gyrus
What is the secondary auditory area?
Posterior superior temporal lobe
What is the tertiary auditory area?
Posterior-inferior part of the temporal lobe
What is the auditory association area?
Superior temporal gyrus
Includes wernicke’s (language comprehension)
What is the sylvian fissure?
A deep cleft seen in both hemispheres (more pronounced in the left)
Separates the temporal lobe from parietal and frontal
It runs between broca’s and wernicke’s (appears to be a marker for linguistic capacity)
Is phonetic awareness required for language?
Yes
Language comprehension requires that phonetically analyzed information be communicated to regions outside the perisylvian region (where sylvian fissure is), including the angular gyrus
What is the angular gyrus?
A region of the inferior parietal lobe of the brain involved in processing of auditory and visual input and language comprehension
Lies between the parietal, occipital, and temporal lobes
It plays an essential role in integration, processing, and connection of these different areas
Connected to both broca’s and wernicke’s (which are connected to each other by the arcuate fasciculus)
What do structures around the sylvian fissure mediate?
Auditory and language repetition
Language repetition is crucial for language acquisition and vocabulary development
Even short repetitive exposure to novel words causes an increase in the rapid neural response suggestive of the formation of trace-memory
What processes auditory signals?
Heschl’s gyrus
Phonemic analysis probably takes place in the adjacent auditory association cortex (Wernicke’s area)
Speech is encoded by more anterior regions, among them Broca’s area, that directs the adjacent motor cortex to produce appropriate movements for speech production
What does damage to any of the regions near the sylvian fissure (brocas, wernickes, etc.) result in?
Impairs language repetition
Hallmark of the perisylvian aphasias
Is CAPD a controversial issue?
Yes
It means different things to different people
What is aphasia?
An impairment of language, affecting the production or comprehension of speech and the ability to read or write
Expressive and receptive abilities affected
Linked to brain damage by Broca, Wernicke, and Freud
Is aphasia always due to a brain injury?
Yes
Most commonly following a stroke particularly in older individuals
But aphasias also may occur with other cerebral disorders including brain tumors, head trauma, infections, dementia, and multiple Sclerosis (MS)
What is wernickes?
Lies in the left temporal lobe, adjacent to the primary auditory area
Language development and usage can be seriously impaired by damage (sensory/receptive aphasia)
Many patients are unaware that they make little sense when they speak
Affects individuals reading and writing
They also may have trouble understanding the speech of others
What is wernickes aphasia?
Receptive aphasia
Fluent, but nonsensical speech
Flowing gibberish
Speech, while frequently containing strings that conform to the grammatical rules of language, has no coherent meaning and typically includes made-up words
Damage to this area leads to similar deficits in people with different native languages
Linguistic function of this area does not appear tied to sound in the modern brain, as shown by the evidence of deaf aphasics (signed gibberish)
Where is broca’s area?
Inferior frontal gyrus of the frontal lobe
Controls speech production
Leads to broca’s aphasia
What is broca’s aphasia?
Motor or expressive aphasia
A signer also has trouble articulating signs and cannot communicate fluently
Most patients are aware of these deficits and easily frustrated
What is brocas aphasia characterized by?
Non-fluent speech
Poor repetition
Few words, short sentences, and many pauses (trying to get the words out)
The words come with great effort and often sound distorted
Flat and monotonic intonation (telegraphic speech) because of the deletion of function words and disturbances in word order
Aural comprehension for conversational speech is relatively intact
Patients may be able to understand speech and read, but may have limited writing skills (due to the fact that it is very close to the motor strip)
Can the cerebellum be involved in certain symptoms of brocas?
Yes
The cerebellum coordinates movements related to exact timing
May have trouble understanding speech because the timing is jumbled
Cerebellum times the way speech is analyzed
Nerves not firing synchronously results in timing issues too
Cerebellum damage can cause agrammatic and imprecise enunciation
Is the ability to speak a quickly timed executed movement?
Yes
Takes skill and timing from the prefrontal cortex and the cerebellum to correctly speak
Needs some executive function to produce it
Are most cases of aphasia mixed?
Yes
Not usually so distinct
Probably due to close connections between brocas, wernickes, and auditory areas
Cortical damage is typically not limited to a small area
What is global aphasia?
When a stroke or other condition affects an extensive portion of the front and back regions of the left hemisphere
May have great difficulty in understanding words and sentences
May have great difficulty in forming words and sentences
May understand some words but not others
Be able to utter a few words at a time
Have severe speech/language difficulties that prevent them from effectively communicating
What is anomia?
A specific type of aphasia
Difficulty remembering the proper word to describe an attribute, action, or object
More evident with infrequent words
Results from cortical or subcortical strokes or cerebral insults
Circumlocutions
What is circumlocutions?
Using more words that necessary to identify an object because they cannot remember the exact word
The fuzzy things that you wear on your feet in winter
Common
What was auditory agnosia or word deafness?
Neurologists coined these terms to describe individuals who could hear and see but could not identify objects
Describe this in victims of head wounds during WW1
Probably the early definition of central deafness
Were non-brain injured children with normal hearing also studied for these same central issues?
Yes
They demonstrated difficulty separating auditory foreground from auditory background
They also had poor language and academic skills
Took a leap of faith and assumed the same issue or damage is occurring in their brains as the adults (where the first controversy is)
Early seeds of CAPD
Who is credited with conceptualizing CAPD?
Helmer Myklebust
One of the first people to make the leap from demonstrable severe brain injury to milder manifestations of perceptual disorders
He reported that some children could hear but not sufficiently for normal language development
He described it as “disturbed” auditory perception without an apparent language disorder
One of the fundamental difficulties of these children was that they could not attend selectively to sound (all sounds are foreground sounds)
Did not suggest that it was auditory specific (multi-modal)
Often associated with analogous disorders of vision (but could occur independently)
Is there a controversy related to the foreground and background issue?
Yes
It is easy to get confused with ADHD because they experience the same thing
Could also be confused with other conditions
What did the Italian researches in 1950 hypothesize?
Lesions in the auditory cortex were not likely to be revealed by conventional speech audiometric tests
Much more difficult listening tasks were required to reveal these lesions, such as “speeded speech”
Used to assess patients with temporal lobe tumors, but it intuitively could assess patients without hard neurological signs too
When was the idea that auditory deficits can impede normal learning?
1947
A child who has suffered a brain injury or infection before, during, or after birth can show disturbances in perceptual thinking and emotional behavior, together or independently
And that such disturbances can negatively affect the normal learning process
What are the two current approaches to CAPD?
Audiologic and psychoeducational
What is the logic behind the audiologic approach?
If (C)APD is a disorder of the CANS, then it is inferred that individuals with lesions to the system should perform poorly on (C)APD tests
If a child performs in the same way on similar tests then a lesion in the same CANS structure is suspected
But they have no hard CANS lesions (leap of faith made)
Two people may have the same injury/symptoms but the etiology maybe different
Were many of the current CAPD tests standardized on individuals with brain lesions?
Yes
The SCAN-3C test
The Staggered spondaic Words (SSW) test
The Pediatric speech Intelligibility (PSI) test
What is the psychoeducational approach?
Built on the premise that a set of auditory abilities can be tested by appropriately devised measures
Example is the goldman-fristoe scale (testing auditory discrimination, auditory memory, auditory selective attention, and sound-symbol association)
The question of how the tests or results relate to auditory brain function is not clearly addressed
What did many language specialists hypothesize?
Problems in auditory perception can cause problems with language acquisition
Others think that auditory processing is only one component of language processing (factors other than auditory perception, such as cognition, language experience, and attention, may contribute to normal language processing)
What is bottom-up processes?
Sensory perceptions
Hearing is bottom-up
Builds cortical networks
Without hearing, spoken language development is not possible
Without strong language development, efficient learning will not occur
Cortical networks are required to refine the sensory perceptual processes
Is there a standardized definition for CAPD that is accepted by all?
No
Is there a gold standard or universally agreed upon diagnostic test or criteria for the assessment/diagnosis of CAPD?
No
Are there evidence-based or standardized management techniques for CAPD?
No
