Test 3 Flashcards
“compensatory or functional communication” target
day-to day- communication abilities
“compensatory or functional communication” goal
improving functional communication and quality of life> reducing impairment
“impairment-based” or “restorative” target
language impairment/processes (phonological)
“impairment-based” or “restorative” goal
generalisation beyond trained items/tasks, and to the communicative environment of the person
- reducing impairment> improving success of communication
Compensatory approach Pros
- focus on functional strategies for daily life
- easy for client to see impact
- easier for clinician to administer
- fit into limited number of sessions
compensatory approach cons
- functional strategies often limited in their overall impact on impairment
Impairment-based pros
greater improvement on overall language processes (generalisation)
impairment-based cons
- less immediate impact for client
- more difficult for clinician to administer
- may require more treatment sessions (potentially exceeding what insurance will cover)
generalization
the transfer of treatment gains to untreated items and every day, non-clinical environments
- ultimate treatment goal
Neuroplasticity
- use, improve, or lose it
- specificity rebuilds targeted networks
- salience is essential
- repetition and intensity promote learning and consolidation
- promote generalisation; avoid interference
- complexity enhances learning and generalisation
Models of language processing
- classic model of language processing
- modern models of language processing
Classic Model hypothesis
brain mechanisms are involved in word access/storage
Wernicke-Geschwind- repetition of spoken words
auditory cortex-> Wernickes area-> arcuate fasciculus-> Brocades area-> motor cortex
Wernicke-Geschwind- reading aloud of written text
visual signals-> angular gyrus-> Wernicke’s area-> arcuate fasciculus-> Broca’s area-> motor cortex
Strengths of Wernicke-Geschwind model
- aid framework for modern models
- started our thinking about pathways involved in comprehension and production of speech and language
- comprehension: acoustic-> concept
- spontaneous speech: concept-> motor
Problems with Wernicke-Geschwind model
- too simplistic
- only models lexical processing, not language processing
- many aphasias don’t fall into these categories
- single lesion sites don’t correspond to single deficits
functional anatomical model
- model (typical speaker) of two auditory speech processing networks, connected to BOTH motor and conceptual systems
functional anatomical model- dorsal stream
mapping sound onto sub-lexical and articulatory-based representations
- ex. speech perception and production
functional anatomical model- ventral stream
mapping sound onto meaning
- speech recognition
speech perception (dorsal stream)
- activate and maintain sub lexical items such as phonemes and related articulation
- perceiving speech sounds
- ex. “rhughet” I perceive speech sounds (they are familiar)
speech recognition (ventral stream)
- access the lexicon/stored words
- recognising words
- ex. “rhubarb” “I recognise that word”
Dorsal stream
- left-hemisphere dominant
-acoustic information received - auditory sensory/phonological + motor interface
- articulatory network
- measures of speech motor impairment
Ventral stream
- bilateral
- acoustic information received
- phonological + semantic-> lexical
- higher-level syntax/ combinatinatorial network;
… before moving on to articulation… - measures of impaired speech comprehension
representation
how language is represented- phoneme, morpheme, grapheme/letter, lemma/word form, lexical item/word, concept
process
how language is activated/accessed
modular language models
- also called box-and-arrow, local, or discrete
modular language models representation
- language units are stored locally (together)
modular language models processing
- language units are processed serially (one at a time, in order)
Distributed language models
also called connectionist
Two connectionist models:
1. parallel distributed processing (PDP)
2. interactive activation
Distributed language models representation
language is represented in terms of learned patterns/networks of activation between different knowledge units
Distributed language models processing
knowledge is processed in an interactive manner; not sequential, serial manner
Basic connectionist model principles
- knowledge (language) can be described by interconnected networks of units
- these networks or patterns of units are activated depending on the strength of the network/patterns
Basic connectionist model principles- spreading activation
- when a neutron/unit is activated, it spreads to other neuron’s/units connected to it
Basic connectionist model principles- learning
- ex. speech therapy
- learning is modifying the connections between units
Parallel Distributed Processing- Connectionism
-interconnected networks> representation
- language must me PROCESSED (not just retrieved)
Parallel Distributed Processing
- strength of representation depends on network strength
- more experience/familiarity with representation = greater network strength (connection weight)
Highlight of lecture 9
- aphasia is an impairment of language processing
- models help us understand the specifics of impairments and support clinical decision-making
Modular Models highlight
- localised representations, serial processing
- useful to consider some speech/language phenomena
Connectionist Models highlight
- interactive networks of sub lexical units
- networks connect with and between modalities
- strength of networks based on experience (learning)
Aphasia and Learning
- principles of neuroplasticity
- Learning in aphasia rehabilitation
Learning in aphasia rehabilitation
- errorless learning
- knowledge of results vs performance
Treatment/rehabilitation is learning, learning requires:
- attention
- memory
- executive function
-language - visuospatial skills
attention
attend to treatment tasks
memory
remember instructions
executive functions
work towards a goal
visuospatial skills
to attend to visual stim, facial expression, gesture
important learning components
- multimodal approach to more richly encode info
- intentional cueing framework
- metalinguistic instruction
Feedback: presence, absence, timing
low frequency feedback
may promote learning better than high frequency feedback in many context
high frequency feedback
may promote learning when training complex skills
Performance
- feedback about performance/process
- helpful during training on specifics of performance
Results
- feedback about correctness of response
- helpful in retention of trained skills
retrieval practice
self generated picture name with correct response feedback provided
- best to strengthen semantic-lexical connections
errorless learning
repeated exposure to the stimuli and its name before naming attempted
- networks tapped: lexical and phonological
- best to strengthen lexical-phonological connections
Picture Naming Task- Stage 1
meaning to a word
- required to name a picture
Picture naming task- stage 2
Word to phonology
- required to name a picture and repeat a word
Aphasia Therapy- Prior approach
focus primarily on language impairment
Aphasia Therapy- emerging approach
focus on the language impairment (restorative) and overall life satisfaction and participation (compensatory)
Aphasia Therapy- common approach
focus on life satisfaction and participation (compensatory)
Aphasia Therapy- Goal
generalization of the targeted language skills to a) untrained items and b) functional communication in the real-world
- selecting appropriate/adequate stimuli
- involving the patient and family/caregivers in treatment planning
- extending treatment outside the clinic
Who is the target of therapy?
- the person with aphasia is the central focus of the rehabilitation process
- family members, friends, colleagues, and health-care workers that need to be able to communicate with patient are involved
Who decides what therapy to give?
- predominant/traditional paradigm is SLP as expert; therapist-led approach
- emerging trend as expert; client-led approach
Therapy considerations- client
- profile of impairment
- priorities for improvement
- insurance, access to therapy, motivation, more
Therapy considerations- clinicians
- knowledge/training
- environment
- perspectives on spontaneous recovery
spontaneous recovery
- relatively rapid recovery in the weeks and months after stroke
- 3-6 months; some consider up to 12 months post CVA
- recovery is never limited
RTSS Significance to SLP
treatments may be modified or administered differently than developed or tested-> impact not treatment outcomes
RTSS Purpose- active ingredients
- what the clinician does to evoke change
RTSS Purpose: Mechanisms of Actions
how the treatment works
RTSS Purpose: Treatment targets
the aspect of functioning targeted for change
Aphasia is an impairment of language ____
processing
attention =
-processing resource
- variable cognitive resources for processing
- language networks require resources or “fuel” (attention) to boost activation of target items and inhibit distractions
allocating attention means:
more fuel and therefore more activation to target or process or items
short term memory
items temporarily activated from long-term memory/sensory input
Tasks: simple serial recall
more attention is required for _______ tasks than for ______ tasks.
working memory tasks
short term memory tasks
PWA with stronger semantic processing better
- at the first words
- primary bias
PWA with stronger phonological processing better
- last word
- recency bias
working memory
ability to maintain and manipulate items for more complex cognitive tasks (like language)
- ex. in conversation, remembering what your partner said a few moments ago
Attention with distraction
- the more prominent the accompanying distraction, the more attention is required for the task
Attention with task complexity
- greater the task complexity, the more attention is required for the task
Suppressing distractions
many believe inhibition (suppressing distractions) requires attention
- inhibition is essential of language processes
continuity hypothesis
- neurologically healthy adults appear to have aphasia If certain factors are manipulated
- diminished or misallocated attention may account for the variability, stimulability, multimodality, and transience observed in aphasia
Language Processing requires:
Attention+ short term memory+ working memory
Cognitive Linguistic Quick Test
- sustained attention/vigilance (also hemianopia/ visual attention
- examinee scans a printed page of symbols that includes target symptoms and foil symptoms
Cueing hierarchies
- a structured approach to supporting response selection
- may straighten semantic, phonological networks
- some evidence of generalization
- a good learning tool for considering impairment, language processes
phonological cueing
- therapy uses a phonological hierarchy of least to most cues
- Picture (cake)
- rhymes with “zake”
- model
semantic cueing
- picture (duck)
“swimming bird, wide beak” - “he carved a wooden duck”
Aphasia is a disorder of:
- linguistic access
- lexical retrieval is a variable in aphasia
- representations are not gone, just inaccessible
- other cognitive processes necessary for retrieval
Connectionist models can
- help us characterise the impairment
- emphasise processing over-representation
- help identify treatment stimuli and approaches
Lexical-semantic word Error types
- semantic substitutions
- mixed errors/formal errors
semantic substitution example
- cat for dog
- knife for fork
mixed errors/formal errors
- (lexical+phono)
- cat (for) rat
Characteristics of the stimuli
- word frequency
- word imageability
- word length
-lexicality
word frequency and word imageability
- tap more into lexical and lexical-semantic properties
word length and lexicality
- tap more into lexical and phonological properties
Phonomotor Treatment
- by straightening phonological level representations, bidirectional spread of activation:
- bottom up to conceptual semantics
- topdown: when a word is activated, previously weak phonological representations will not be stronger and more easily accessible
Developmental connection between phonology, orthography, and reading
- first, semantics -> phonology for communication
- later, phonology-> orthography
Word
a pattern of activity distributed over a set of orthographic units, phonological units, semantic units
Alexia
acquired difficulty with reading
2 types of Alexia
- Peripheral Alexias
- Central Alexias
Peripheral Alexia
- visual/perceptual; not aphasia
Central Alexias
often associated with aphasia
- step from linguistic processing impairment; difficulty deriving sounds and/or meaning from print
Surface Alexia
-impaired reading of irregularly spelled words
- regularisation error: “pint” rhymes with “mint” when read aloud
- BUT relatively intact reading of regularly spelled words and pseudo words
-Good grapheme to phoneme conversation
Phonological Alexia
- impairment in pseudoword reading
- no semantic reading errors
- lexicaliztation errors (flig-> fig)
- visual errors (signal-> single)
Morphological errors (baked-> baking)
Rely on sight word reading/whole word recognition- poor grapheme to phoneme conversion
-imageability effects: highly imageable words better than abstract words
Deep Alexia
- severly impaired pseudoword reading
- semantic errors in oral reading (semantic paralexia- (boot->shoe)
- lexicaliztation errors
- visual errors
- morphological errors
- imageability effects:highly imageable words better than abstract words
How Alexia Types are Classified
- locus of impairment
- Relative processing strengths/reliance
- Accuracy and Error Features
Duel Route Model
- reading invoices with several independent components and two separate processing routes (lexical and sub-lexical)
Use sub-lexical route with
-unfamiliar or nonwords
-identify and parse graphemes
-grapheme to phoneme rules
-blending of graphemes
use lexical route with
-stored word knowledge
-familiar real words
a person with surface alexia relies on…
-sublexical route
-grapheme to phoneme rules
a person with phonological alexia relies on…
-lexical route
-stored word knowledge
-familiar real words- regular and irregular
a person with deep alexia relies on…
-lexical route
- Some stored word knowledge (highly imageable words)
- makes semantic errors
A likely underlying contributor to reading difficulty in aphasia…
- general impairment in phonology
- break down in connection between the letters and their corresponding sounds
successful audition of language
-stimulus detection
-discrimination of stimuli
-retention
-categorization
-sequential retention
stimulus detection
awareness and attention
discrimination of stimuli
recognising minimal differences
retention
short and long term storage
categorisation
comparing stimulus to storage
sequential retention
organizing stimuli over time
Mortons Logogen Model
- Hear Word (spoken word)
-> - Auditory phonological analysis (analysis of the sound wave and phonological elements)
-> - Phonological input lexicon (access storage of known spoken words)
- Semantic system (access of word meaning)
Dell’s Spreading Activation Model- Heard Word
- Auditory/speech level: (pre lexical): spoken word is heard, phonological aspects analysed
- Lexical level: (Phonological in put lexicon): access store of known words
- Semantic level: (meaning) access semantic knowledge, combined features
Auditory speech level (pre-lexical) processing
- auditory analysis carried out bilaterally
-left lateralized speech-specific processing - Imaging studies show: activation of primary auditory cortex during auditory comprehension
-Lip reading has been shown to be integrated with auditory information
Mirror neurons
-motor theory of speech perception:
- speech production and speech perception processes overlap
-activation of the primary motor cortex during auditory comprehension
-auditory input: phonological perception is linked to phonological production
lexical level
-phonemes detected have a spread of activation upward to lexical level
-activate the lexical node/knowledge
-activated only words previously learned
semantic level
- the lexemes detected have an upward spread of activation to semantics
-activate the correct word for comprehension of meaning
-heavily dependent on verbal short-term and working memory
Assessment of comprehension
- first consider hearing impairment
-WAB
-CAT
Auditory Comprehension General treatment considerations
-patients will moderate-sever e auditory comprehension deficits may be more difficult to engage in therapy
- may not be able to perform more structured tasks
Marshall reccomends…
-context based approach
-clinician must be flexible
-focus on overall successes in communication, rather than what the person says or how he/she says it
-experiment with different strategies and strategy combinations to improve message comprehension and exchange
Maximizing auditory comprehension: communication strategies:
- consider extralinguistic variables
- body and face orientation
-environment: other auditory and visual inputs
-facial expresssion
-gesture
-visual aids (key words, symbols, pictures)
-Manipulate linguistic variables - manipulate timing variables
maintain communication flow
- if there is excessive flow:
- utilise stop strategy to improve patient’s ability to recognise and repair errors
- interpret and translate patient’s errored utterances
