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Language and Cognition Colombo 2011. Psycholinguistic Assessments of Language Processing in Aphasia – Word comprehension With acknowledgement to Jane Marshall. Aims of Lecture. Clarify processes involved in auditory comprehension Introduce other relevant processes (repetition and writing)
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Language and CognitionColombo 2011 Psycholinguistic Assessments of Language Processing in Aphasia – Word comprehension With acknowledgement to Jane Marshall
Aims of Lecture • Clarify processes involved in auditory comprehension • Introduce other relevant processes (repetition and writing) • Familiarise students with methods for assessing comprehension • Develop skills in interpreting test data • Introduce methods for treating comprehension problems
Speech Pictures/Objects Writing Auditory Analysis Picture Analysis Visual Analysis Picture Recognition VIL AIL GPC Semantics POL OOL Buffer Buffer PGC Speech Writing
Minimal Pairs tack cat farl farl tome tome poob poom • Demonstrates ability to carry out auditory analysis • Lexical effect? AIL or Semantics prime auditory analysis • Requires ability to retain and compare two spoken words, and accurate ‘yes’/’no’
Auditory Lexical Decision hotel prisciple dogma trantor • Assesses ability to access AIL • Requires ability to hold the word in head and indicate yes/no • Imageability effect? Suggests that decisions are supported by Semantics • Be aware of ‘yes’ bias
Word to picture matching • Tests the person’s ability to access semantics from the spoken word • Often a good place to start with testing
Synonym Judgements • Boat ship • Boat flower • Idea notion • Idea democracy Imageability effect? Many aphasic individuals find concrete items easier than abstract.
Speech Pictures/Objects Writing Auditory Analysis Picture Analysis Visual Analysis Picture Recognition VIL AIL GPC Semantics POL OOL Buffer Buffer PGC Speech Writing
Repetition • Supplements input testing. • Words v’s non Words • Concrete words vs abstract words Words ☺ non words x Non lexical route x AIL ☺ Note: Any repetition skills show AA ok. Repetition may occur without comprehension
Spelling to dictation Words vs non words Regular vs irregular words Note: • Ability to spell indicates that at least AA is functioning • Spelling may occur without comprehension • Failure may be due to writing problems rather than input difficulties
Testing Issues Consider other reasons for failure, e.g.: • Attention • ability to point • Auditory short term memory • ability to signal yes/no • comprehension of pictures Compare spoken with written input, to distinguish central semantic from peripheral problems Think about chance
Speech Pictures/Objects Writing Auditory Analysis Picture Analysis Visual Analysis Picture Recognition VIL AIL GPC Semantics POL OOL Buffer Buffer PGC Speech Writing
PK (Maneta et al 2001) • Poor discrimination of minimal pairs • Unable to repeat words • Poor performance in lexical decision • Poor at word to picture matching • Written > Spoken tests
PK (Maneta et al 2001) Conclusion: PK has impaired Auditory Analysis • ‘Word sound deafness’ • ‘Auditory verbal agnosia’ • If no other language impairments: ‘Pure word deafness’
Features of Pure Word Deafness Environmental sounds are distinguished With speech: • Lip reading helps (visual support) • Context helps • Slowed speech helps • Vowel > consonant discrimination • Voices and accents are differentiated A problem processing rapid auditory information?
Speech Pictures/Objects Writing Auditory Analysis Picture Analysis Visual Analysis Picture Recognition VIL AIL GPC Semantics POL OOL Buffer Buffer PGC Speech Writing
AH (Franklin 1989) • Good discrimination of minimal pairs • Repetition of words 81% • Repetition of non words 75% • Poor auditory lexical decision 70% • Poor word to picture matching • Poor synonym judgements • Written lexical decision 94%
AH (Franklin 1989) • Auditory Analysis is ok (minimal pairs and repetition) • Access to AIL is impaired (lexical decision) Word Form Deafness
Speech Pictures/Objects Writing Auditory Analysis Picture Analysis Visual Analysis Picture Recognition VIL AIL GPC Semantics POL OOL Buffer Buffer PGC Speech Writing
Bramwell (1897) Described a woman with very impaired auditory Comprehension She could comprehend environmental sounds: ‘is it not strange that I can hear the clock ticking and cannot hear you speak’ She could also: Speak Read Write
Bramwell (1897) She could often write to dictation Example: ‘Do you like to come to Edinburgh?’ Not understood writes ‘Edinburgh’ reads word and understands question
Bramwell (1897): Conclusions Can write irregular word to dictation: AIL POL OOL Writing • Confirms that AIL is intact • Comprehension problem is due to impaired access from AIL to semantics • Reading shows that semantics is intact and can be accessed from the written word Word Meaning Deafness
Speech Pictures/Objects Writing Auditory Analysis Picture Analysis Visual Analysis Picture Recognition VIL AIL GPC Semantics POL OOL Buffer Buffer PGC Speech Writing
CJ (Franklin 1989) • Minimal pairs good • Lexical decision good • Word repetition good • Word to picture match impaired • Synonym judgement impaired Written synonyms = spoken synonyms
Impairment in Auditory Analysis PK Maneta et al (2001) Jargon speaker with severe impairments in: • Minimal pairs • Auditory lexical decision • Spoken word to picture matching Problems in following conversation,TV, and using the telephone
Therapy 1 Minimal pair and lip-reading training Tasks • graded discrimination tasks Strategies • lip reading • cued articulation • colour coding
Strategies - Lip Reading • client given pictures of lip to sound correspondences • Advised to watch the speaker’s mouth
Strategies - Cued Articulation Hand signals made next to the mouth Show: • voicing • place of articulation • manner
Strategies - Colour Coding Used where tasks require selection of written words Consistent colours for different places of articulation: • velarcar (brown) • alveolar tar (blue) • labialbar (red)
Task Example: Phoneme to grapheme matching level 1 targets & distractors differ by 2 distinctive features /t/ TGB level 2 targets and distractors differ by 1 distinctive feature /t/ PTK
Task Example:Matching spoken to written words Level 1 “man” tan can man Level 2 “cart” cart tart part
Did it work? Auditory Input Tasks (PK can watch face)Pre Post Minimal pair discrimination 24/40 29/40 Repetition 5/20 11/20 Word to picture matching 23/40 31/40 Small (but not significant) improvements in discrimination
Conclusions from PK • Improving discrimination is difficult (although see Morris et al 1996) • The nature of the impairment may impede direct work • Recent research project at UCL/City • No change on outcome measures (e.g. minimal pair tasks) • Some change in the level of cueing needed during therapy
Word Meaning Deafness Impairment in link between AIL and Semantics • Good minimal pairs • Good lexical decision • Poor auditory comprehension Person can • Write to dictation • Comprehend written words
Therapy ideas for word meaning deafness Listen to word Write it down Read word and understand it • Internalise the writing strategy Give written context (a tool for banging in nails) Say word which is matched to picture (‘hammer’) Reduce context
Central Semantic Problems Therapy aims to improve semantic processing Possible tasks: • Word to picture matching (semantic distractors) • Categorisation • Picture/word association tasks Grayson et al 1997: semantic tasks on a jargon aphasic. Improved performance in spoken and written tasks.
General Therapy Issues Practising input may recover or restore damaged processing But Impaired comprehension may prevent understanding of therapy Input tasks are less amenable to strategies than output tasks So : Therapists often work through other channels
Conclusions • Understanding of speech can fail for different reasons • Assessment aims to determine the level of the impairment • Assessment findings influence therapy decisions, such as the selection of therapy tasks • ‘Direct’ therapy needs to be supplemented with indirect approaches aiming to modify the environment