Assessment of Aphasia. Objectives: Introduction –Definition –nature of the disorder Etiology...
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Transcript of Assessment of Aphasia. Objectives: Introduction –Definition –nature of the disorder Etiology...
Assessment of AphasiaAssessment of Aphasia
Objectives:• Introduction
– Definition– nature of the disorder
• Etiology
• Meaning of phonotactics
• Aphasic characteristics & behaviors
Introduction:Introduction:• Definition:
– is a communication disorder which occurs when damage (lesion) to the adult brain impedes the use of language understanding & production.
• All aspects of language are affected with variable degrees
– Phonetic, phonological, syntactic, semantic, and pragmatic processing & performance are affected in a range of ways
• i.e. different level, extent & complexity of phonetic, phonological, syntactic, semantic & pragmatic problems contribute to the disorder in a particular individual
Introduction (Cont’d)Introduction (Cont’d)• It is described as a multimodal disorder
– The linguistic deficit does not have to be confined to
the expression and comprehension of spoken language,
but may extend to the use of written, gestural & other
symbols
– Ex: reading and writing are different modalities of
language ( which might be affected as well)
• Ideas & Meanings are well preserved
– are conveyed by the use of non-verbal behaviors, such as facial expression, gesture, pointing and drawing
Introduction (Cont’d)Introduction (Cont’d)• Non-linguistic brain functions are most likely to be affected
as well
– such as attention, memory perception, sensory reception,
motor perception, motor skills and emotional responses
• A complex of linguistic as well as non-linguistic factors that together reduce the effectiveness of communication
• A person with aphasia is idiosyncratic in
– neurological impairment, linguistic & non-linguistic behaviors, psychological response, his/her needs & ability as a communicator
EtiologyEtiology::• Brain damage resulting in aphasia can be
caused by various problems such as:– tumor– blood clot– abscess– trauma (e.g. gunshot wound, road traffic
accident, surgical intervention– Infections (meningitis, encephalitis)
• Functions impaired & their severity depend on the location & extent of damage.
Classification of aphasia:Classification of aphasia:
– According to the area affected
– According to the function impaired
Phonotactics:Phonotactics:• Explained in Grundy (page 47)
• term used in phonology
• refers to the way in which a language combines phonemes to make words
• Phonotactic rules:– describe the permissible combinations in a
particular language
Phonotactics (Cont’d)Phonotactics (Cont’d)• Aspects of phonotactics:
1. syllable structure such as;
– CV, CCV open syllables
– CVC, CCVC, CVCC closed syllables
2. particular phonemes that may occur at each position in the syllable structure, e.g.;
– In English, nasals do not occur as the 1st phoneme of a cluster in syllable-initial position /mp-/, /nt-/
– but occur in a syllable-final position as in stamp, went
PHONOLOGY & PHONETICSPHONOLOGY & PHONETICS• Problems in language expression:
• Articulatory awkwardness
– is used to describe the speech sound errors that
contribute to non-fluent speech
– Person searches, visibly & auditorily, for
articulatory positions
– produces variable phonetic errors & also
phonological errors which generally fail to
comply with the phonotactics of the speaker’s
native language
PHONOLOGY & PHONETICS(Cont’d)PHONOLOGY & PHONETICS(Cont’d)
• Articulatory awkwardness (Cont’d)
– is due to a problem of phonetic planning
– Also called verbal apraxia, speech apraxia,
apraxia of speech, aphasic articulatory defect
– it is the exacerbated by an anticipation of error
& attempts to rectify errors as they are made
PHONOLOGY & PHONETICS(Cont’d)PHONOLOGY & PHONETICS(Cont’d)
• Phonemic paraphasia
– phonemic substitutions, rearrangements and
additions, with consonants being affected rather
than vowels, & segment production achieved
with ease or fluently
– phonemes & phoneme combinations that occur
are always consistent with the phonotactic rules
of the speaker’s language, e.g. ‘squottle’ for
‘bottle’, or ‘pusting’ for ‘putting’
PHONOLOGY & PHONETICS(Cont’d)PHONOLOGY & PHONETICS(Cont’d)
• Phonemic paraphasia (Cont’d)
– Presence of sufficient phonologically accurate
aspects of the target word remaining & which
would be identified from the speech context
– Lack of contextual knowledge to interpret
produced word affects how it would be
perceived ‘neologism’
PHONOLOGY & PHONETICS(Cont’d)PHONOLOGY & PHONETICS(Cont’d)
• Neologism
– affects content words making them appear
bizarre to the extent that no real word is
recognized
• i.e. seem as if they are new words
– Words not found in the speaker’s language
– is the result of severe phonemic paraphasia
PHONOLOGY & PHONETICS(Cont’d)PHONOLOGY & PHONETICS(Cont’d)
• Neologism (Cont’d)
– In some cases, neologisms might have structural
resemblance to words in the language that could be
used in the same position in the sentence
• E.g. ‘I am wickling the…’ phonological form is
known but phonemes were misselected/
misordered
– In other cases, neologisms appear to have no relation
to an appropriate type of word for the sentence
structure
• E.g. ‘I am swink that …’
PHONOLOGY & PHONETICS(Cont’d)PHONOLOGY & PHONETICS(Cont’d)
• Problems in language reception:– Phonological or semantic impairment can result
in an impaired single word comprehension
– A range of linguistic and non-linguistic
(context), information are used for
interpretation of the units of speech
SEMANTICSSEMANTICS• Problems in language expression:
• Word retrieval errors– Impairments in the ability to produce lexical
items (vocabularies)– Different behaviors will present depending on
the• person’s processing skills &
• ‘degree of awareness’ – If aware of difficulty
» blocking & search behaviors, such as pauses, hesitations & re-attempts at initial sounds & syllables or at whole words
SEMANTICS (Cont’d)SEMANTICS (Cont’d)
• Language features reflecting problems in lexical retrieval:
• Circumlocution– Subject talks around the target word
• Such as descriptions & definitions
• Semantic paraphrasia– A real word which has the same grammatical function as
the target & has semantic association with its substitute
• E.g. “walking” for “running”
– The phonological structure (number of syllables+ some similarity in the phonemes) of the substitute word is generally dissimilar to the target
SEMANTICS (Cont’d)SEMANTICS (Cont’d)• Language features reflecting problems in
lexical retrieval (Cont’d)
• Verbal paraphasia– A real word which has the same grammatical
function but there is no recognizable semantic association with the target
– The phonological structure of the substitute word may
• show some similarity to the target word– E.g. “walking” for “wishing” ; “chair” for “chalk”
• be dissimilar to the target word (i.e. unrelated in structure)
– E.g. “quiet” for “careful”
SEMANTICS (Cont’d)SEMANTICS (Cont’d)• Language features reflecting problems in
lexical retrieval (Cont’d)
• Perseverative paraphasia– A word which has been expressed in a previous
context is inappropriately repeated in a later utterance
– A result of failure in processing a new response
• Anomia– Refers to disorders of naming rather than word
retrieval in running speech
SEMANTICS (Cont’d)SEMANTICS (Cont’d)• Problems in receptive language:
– Failure to access the meaning of a heard word– Word will be either
• perceived as a meaningless nonsense word or
• interpreted as another concept from a related semantic field e.g. “turnip” for “potato”
– Difficulty in associating a heard word
(i.e. recall) with 1 of 2 closely related pictures/items rather than with 1 of 2 unrelated ones
SEMANTICS (Cont’d)SEMANTICS (Cont’d)• Problems in receptive language(Cont’d):
• E.g. “knife” more likely to be recalled knife-boat
• Less likely to be recalled knife, fork
– Impairment in the ability to interpret thematic relations of a particular verb –reversible verbs
• E.g. “chased” in the “the mouse chased the cat”
• Thematic role are understood if the lexical entry “chased” is understood
SEMANTICS (Cont’d)SEMANTICS (Cont’d)• Factors which affect semantic comprehension:
– Memory span– Information load
SYNTAXSYNTAX• Aggrammatism
– Nonfluent output characterized by speech produced in a disconnected manner
– Function words are omitted to a greater extent than content words
– Grammatical inflections are generally lacking
– Agreement (gender, number and case) is impaired
• Paragrammatism– Function words are distorted but not omitted
PRAGMATICSPRAGMATICS• Usually the least affected aspect of language
• Many clients are able to use non-verbal signals such as – eye-gaze– pause– gesture– prosody– facial expression to indicate meanings
PRAGMATICS (Cont’d)PRAGMATICS (Cont’d)• May also
– engage appropriately in discourse
– adopt effective repair strategies
– demonstrate a range of communicative acts
including;
• acknowledgement
• greeting
• request
• question
• command
PRAGMATICS (Cont’d)PRAGMATICS (Cont’d)• Individuals with severe jargon aphasia can often
convey– communicative intent– emotion– question forms– topic change
• A person with severe verbal comprehension deficits can often make appropriate responses to – yes-no or wh- question– commands etc
because he/she recognizes the meaning implied byProsodic features
Visual cues
Contextual information
PRAGMATICS (Cont’d)PRAGMATICS (Cont’d)
• May make relevant guesses about a message if have enough contextual information
– recognition of people & environment
– orientation in time & situation
PRAGMATICS (Cont’d)PRAGMATICS (Cont’d)
• Pragmatic problems:Pragmatic problems:
– failure to recognize situations
– feigning understanding
– ignoring turn taking signals
– continuing to jargon in spite of a negative feedback
from the conversational partner
– failure to
• initiate conversation
• change topic
• Employ a full range of communicative acts
OTHER SPEECH OTHER SPEECH BEHAVIORSBEHAVIORS
• Jargon
• It consists of fluent, generally incomprehensibles
utterances which may contain any type of paraphasia and
neologism
• Automatic speech
• Well preserved even in severe cases of aphasia
– Serial speech such as;counting and days of the week
– Social responses
– Familiar overlearned sayings
OTHER SPEECH BEHAVIORS OTHER SPEECH BEHAVIORS (Cont’d)(Cont’d)
• Repetitive verbal behaviorRepetitive verbal behavior• takes several forms ; ex.
– recurrent utterances
– Echolalia
– perseveration
– stereotypy• Echolalia; repetition of all/part of an utterance just spoken by
another person
• Perseveration; reproduction of a previous response in a new situation