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

Auditory Analysis

AIL VIL

Visual Analysis

POL OOL

Semantics

Picture Analysis

Picture Recognition

Buffer Buffer

Speech Writing

Speech Writing

GPC

PGC

Pictures/Objects

Assessing Auditory Input

Minimal Pairs

tack cat farl farltome 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 priscipledogma 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.

Auditory Analysis

AIL VIL

Visual Analysis

POL OOL

Semantics

Picture Analysis

Picture Recognition

Buffer Buffer

Speech Writing

Speech Writing

GPC

PGC

Pictures/Objects

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 wordsRegular 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

How do different impairments manifest?

Auditory Analysis

AIL VIL

Visual Analysis

POL OOL

Semantics

Picture Analysis

Picture Recognition

Buffer Buffer

Speech Writing

Speech Writing

GPC

PGC

Pictures/Objects

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?

Auditory Analysis

AIL VIL

Visual Analysis

POL OOL

Semantics

Picture Analysis

Picture Recognition

Buffer Buffer

Speech Writing

Speech Writing

GPC

PGC

Pictures/Objects

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

Auditory Analysis

AIL VIL

Visual Analysis

POL OOL

Semantics

Picture Analysis

Picture Recognition

Buffer Buffer

Speech Writing

Speech Writing

GPC

PGC

Pictures/Objects

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:SpeakReadWrite

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

Auditory Analysis

AIL VIL

Visual Analysis

POL OOL

Semantics

Picture Analysis

Picture Recognition

Buffer Buffer

Speech Writing

Speech Writing

GPC

PGC

Pictures/Objects

CJ (Franklin 1989)

• Minimal pairs good• Lexical decision good• Word repetition good• Word to picture match impaired• Synonym judgement impaired

Written synonyms = spoken synonyms

What about therapy?

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:• velar car (brown)• alveolar tar (blue)• labial bar (red)

Task Example: Phoneme to grapheme matching

level 1

targets & distractors differ by 2 distinctive features

/t/ T G B

level 2

targets and distractors differ by 1 distinctive feature

/t/ P T K

Task Example:Matching spoken to written words

Level 1

“man” tan can man

Level 2

“cart” cart tart part

Task Example:Word to Picture Matching (Level 1)

“toy”

Task Example:Word to picture matching (level 2)

“tart”

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 wordWrite it downRead 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

ButImpaired 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