Week 4 Flashcards
Word Processing
- Nearly All PWA have comprehension deficit at some level
- Show written word and have PWA select correct picture
- Often a matching activity
Functional Levels of word Processing
- Sensation: I hear something
- Perception:
a. Discriminate between 2 sounds (same or different?)
b .Identification task (point to the /b/ sound)
c. Discrimination-identification (point to ‘fan’) - Recognition: recognizing a word, not necessarily understanding it. (Lexical decision task: is this a word?)
- Comprehension of word
Semantic Memory
concept that matches what we’ve heard and lexical representation as well
Concept
unit of semantic memory, e.g., ‘cat picture’
Lexeme
‘cat’, ‘chat’.. depending on language; written representation with letters
Semantic Networks
- How concepts are organized
- Related concepts are close together -> neighbors
- Less related concepts are more distant
- Are culturally dependent
Semantic Priming Effect
- Lexical decision task with semantic priming effect.
a. Prime: nurse (related); flower (unrelated)
b. target is doctor - Lexical decision is faster when preceded by a semantically related prime vs unrelated prime = semantic priming effect
- PWA demonstrate semantic priming effect
- Ambiguous primes with multiple meanings activate both meanings.
Attributes of sentence comprehension
1.Complexity – passive more difficult than active
-Negative makes it more difficult
-Embedded clause is harder
-Think about complexity as a continuum
- Reversibility
-It will be more difficult if reversible - Canonicity
-Easiest to understand structure
(Assess comprehension across different tasks)
Sentence comprehension deficits
o Need to understand thematic roles
-What’s the role of this or that noun
o How do we assess clients sentence comprehension?
-Match a sentence to a picture
-Follow instructions to manipulate objects
-Answer questions
Explaining comprehension deficits: Why do people with PWA have difficulties with sentence structure?
o Lexical processor
o Syntactic processor
o Interpretive processer
-Are these operating at the same time or in order?
-Are all damaged? Or just some?
Lexical system and sentences
o Lexical decision task with priming sentence for ambiguous word
o E.g., plant
o Pw/oA people define ambiguously
o PWA prime for only one meaning in context
Syntactic parsing mechanism
brain assigns structure to the words that we hear
Syntactic system & sentences: Processing theories
- may be identified with general cognitive systems such as working
memory - syntactic information associated with inflection isn’t activated fast enough
- syntactic processor isn’t impaired in an all-or-none fashion, is impaired
partially - People with aphasia don’t activate meanings of morphemes quickly enough
Do PWA have a cognitive limitations?
attention that exacerbate a language-specific
difficulty
* maybe
Is STM implicated?
not in comprehension deficits
Symptoms of Confrontational Naming Task
- Slow to respond
- Vague words
- Circumlocutions
- Paraphasias
Visual Agnosia
-Word errors not due to aphasia
-deficit in recognizing an object despite a normal visual system
-might recognizing the object through touch or hearing it (sound it makes)
Cognitive Neuropsychological
Model
- Operates serially (in a set order)
- For PWA, does the impairment lie in the semantic system or lexical system?
- Chart: 1st step problem = visual agnosia
-Semantic is the concept of meaning
-Phonological is the word itself
Chart: Picture of object -> Picture recognition -> Conceptual Semantic System -> Phonological Output Lexicon -> Articulatory Processes -> Spoken Name
Semantic Deficit
naming specific category could be a semantic deficit
Lexical Deficit
-they can do naming task
-can access first letter but not word
Psycholinguistic Model
- Not differentiating between storage and process
- Simultaneously, rather than Serial fashion
- Picture word interference task
-Measure time to name picture
-Competing word
-Interference from semantically related word slowed them down
-Lexical access speed things up
Action Naming (Verbs)
- Are there grammatical category-specific deficits?
- Which is more difficult, verbs or nouns?
- posterior damageà nouns
- anterior damage à verbs
- Does that mean nouns and verbs are stored like this?
Word Retrieval and Fluent Aphasia
- anomic or other fluent aphasia -> emphasize word-finding over sentence structure
- narratives vs. picture naming
- word finding in narratives better than picture naming
- we should assess word retrieval with
- naming
- narration
- and probably, conversation
What does circumlocution reveal about semantic vs lexical information?
- one study:
- show pictures of famous people
- in cases of anomia, people w/anomic aphasia
- gave semantic information 91% of the time
- identified first letter only 7% of time
Conduction Aphasia and Word Retrieval
Lexical access problem?
Wernicke’s Aphasia and Word Retrieval
- more errors overall
- less likely to have ”tip of tongue” syndrome
- Neologistic jargon or semantic jargon?
- semantic access vs. lexical access?
Grammatical Symptoms
- Grammatical Morpheme Omissions
- Grammatical Morpheme Substitutions
- Structural simplification
-Actives > passive structure
-Fewer subordinate clauses
-Simple sequences, e.g., “a large house, a white house” rather than “a large, white house” - Don’t make high level structural errors (e.g., illegal word order)
Agrammatism and Broca’s
- People with Broca’s seem to retain grammatical knowledge (*Can tell when a sentence is not right)
- People with agrammatism activate a canonical form to convey message. (e.g., simplification strategy)
(Lost access to more complex grammar)
Have PWA lost Grammar knowldege?
No, PWA have not lost knowledge of grammar
-> impairments should be identified with processing
- if aphasia is an impairment of processing, that affects how
we approach therapy - try to figure out where/what level the impairment is
Sublexical or Nonlexical Reading Route
Does not depend on activation of words in the lexicon
-See word in print-> letter-to-sound conversion -> phonological buffer
e.g., flig, skurt, lemmun, kattul
Where to assess reading impairments?
Assess at word, sentence, and paragraph level when possible
Alexia
o Disruptions at different points along the pathway
o Orthographic lexicon: storage of familiar strings of letters
o Phonological buffer = short term WM
o You can skip semantic system to phonological buffer (sublexical route)
o Not reliable with certain words like ‘yacht’
Pure Alexia
- aka, alexia without agraphia
- retain ability to spell and write
- impairment between visual and
language system - will do letter by letter strategy
- short words easier
o Specific to reading
o No writing issues
o Can still access othrographic input lexicon, just need to do it letter by letter
o Longer words likely to be slower and wrong
Surface Alexia
Impairments in the lexical semantic
reading route
Difficulties with:
* irregular spellings, e.g.,
* homophones, e.g.,
* homographs, e.g.,
* low frequency words more difficult
o Impairments between lexical and semantic systems
o damage could be in a few different areas
Phonological Alexia
-Sublexical Route
o non words will be harder
o lexicalization: ‘dusp’ read as ‘dust’
-Sound to letter and letter to sound conversion blocked
Deep Alexia
o Same as phonological alexia with damage to semantic system
Agraphia
- ASSESS
- spontaneous writing
- written naming
- writing to dictation
- copying
Phonological Agraphia
- difficulty spelling nonwords
- spelling errors typically not
phonologically plausible - e.g., flewen for ‘flower’
o take a nonword like dusp make it dust
(sound to letter conversion blocked)
-Impairment: Sublexical Route
-High frequency > low frequency
High imageability > low imageability
Content words > grammatical
❌ non-words
Deep Agraphia
-Impairment: Semantics + phonological
-High frequency > low frequency
High imageability > low imageability
Content words > grammatical
❌ non-words
❌ semantic errors
Surface (lexical) agraphia
- lost or degraded orthographic
representations
Difficulties with: - irregular spellings, e.g.,
- homophones, e.g.,
- low frequency words more difficult
-Impairment: Orthographic output
Regular words > irregular words
High frequency words > low frequency
Graphemic Buffer Agraphia
-Impairment: Graphemic buffer
-Short words > longer words
o longer words are going to be harder just because they are longer
- a short-term memory issue
- lexical-semantic and sublexical
routes are intact - long words more difficult than
short words - types of errors:
- omissions, e.g., sweater ->sweatr
- substitutions, e.g., peanut -> peanul
- transpositions, e.g., painter -> painetr
- additions, e.g., flower -> flowaer
Allographic conversion agraphia
-well-formed but incorrect letters or
disturbed letter formation
-Preserved oral spelling
selective impairment:
* upper vs. lower case
* print vs. cursive
Person will have preserved copy, but
impaired transcoding (e.g., ask to
transcode from upper to lower case)
Allographic conversion agraphia:
treatment
use self-dictation!
Alexia/agraphia: summary
- identify where person has impairment
- which type of words are hard to read or write?
- Note: there is no fixed relationship between aphasia type and alexia/agraphia deficits
