PSYC443 - AutismPSYC443 - AutismCentral CoherenceCentral Coherence

Dr Jason LowDr Jason Low

School of PsychologySchool of Psychology

Victoria University of WellingtonVictoria University of Wellington

The triad: No single cognitive explanation

Communication Communication impairments impairments

Social impairmentsSocial impairments

Restricted/ Repetitive Restricted/ Repetitive Behaviours & InterestsBehaviours & Interests

Problems recognising thoughts and feelings?

Problems generating, planning, monitoring?

“Theory of mind”

“Executive functions”

Limitations to theory of mind & EFT Limitations to theory of mind & EFT deficit based accountsdeficit based accounts

• ToM and EF deficits may explain problems in ToM and EF deficits may explain problems in autismautism

• But people with autism also show But people with autism also show superiorsuperior performanceperformance• savant skills in music, maths, art...savant skills in music, maths, art...• excellent memory for facts...excellent memory for facts...• jigsaw puzzle and other spatial skills...jigsaw puzzle and other spatial skills...• noticing tiny changes, perfect pitch...noticing tiny changes, perfect pitch...

• Current deficit accounts (ToM, EF) can’t explain Current deficit accounts (ToM, EF) can’t explain thesethese

Central CoherenceCentral Coherence

In autism, specific imbalance in integration In autism, specific imbalance in integration of information at different levels (Frith, of information at different levels (Frith, 1989)1989)

In normal development, we have a In normal development, we have a tendency to process information in contexttendency to process information in context

This contextual processing is missing in This contextual processing is missing in autism, so they should be good in tasks autism, so they should be good in tasks that emphasise piece-meal processingthat emphasise piece-meal processing

Puzzling jigsawsPuzzling jigsaws

Frith & Hermelin (1969)Frith & Hermelin (1969)Contrasted performances on two types of Contrasted performances on two types of

jigsaw (jigsaw by shape vs. jigsaw by picture)jigsaw (jigsaw by shape vs. jigsaw by picture)Autism > normal for jigsaw by shape.Autism > normal for jigsaw by shape.

Hidden FiguresHidden Figures Shah & Frith (1983)Shah & Frith (1983)

Children’s embedded Children’s embedded figures testfigures test

Children with autism Children with autism scored above average scored above average for their mental age.for their mental age.

Block DesignBlock Design Block design test: the big Block design test: the big

shape has to be copied shape has to be copied with the little building with the little building blocksblocks So the first step is to So the first step is to

separate the given design separate the given design into appropriate segmentsinto appropriate segments

Shah & Frith (1993): Shah & Frith (1993): Autistic children obtain a Autistic children obtain a score as good and often score as good and often even better than normals.even better than normals.

Sentence Completion task: example of a CC test 1. I was given a pen and ... *2. The sea tastes of salt and ...3. Hens lay eggs and ...4. The woman took the cup and ... *5. You can get burnt by the sun and ...6. You can feed a child bread and ... *7. Little boys grow up to be men and ...8. In the sea there are fish and ... 9. In a cave lived a bat and ...10. You can go hunting with a knife and…11. You can swallow apple ... *12. The old shoe-maker mended the shoes and ...13. The fireman carried the bucket and ...14. A vet cares for cats and … *15. The night was black and ... 

SEE

PEDANTIC

MIND

DOG

PIONEER

SHIP

LEAF

WHERE

COMMUNICATE

EARLY

THROW

THE

IS

Rote MemoryRote Memory

Recall string of random words longer than usual digit Recall string of random words longer than usual digit span: both autistic and normal – remembered end of span: both autistic and normal – remembered end of string (Frith, 1970)string (Frith, 1970)

But what happens when part of string is a sentence?But what happens when part of string is a sentence? see-where-the-ship-is-….-early-communicate-leaf-see-where-the-ship-is-….-early-communicate-leaf-

throwthrow Normal – sentence part; autistic – early-communicate-leaf-throw Normal – sentence part; autistic – early-communicate-leaf-throw

(just as if random)(just as if random)

More on rote memoryMore on rote memory

Even with super-long strings – normal Even with super-long strings – normal children did wellchildren did well

Sentence structure and meaning helpsSentence structure and meaning helpsAutism: only slightly better at recalling Autism: only slightly better at recalling

sentences than jumbled words, and overall sentences than jumbled words, and overall poorer than normalspoorer than normals

Elements and their contextElements and their context She took the shoe polish away with her.She took the shoe polish away with her. She took the Polish man away with her.She took the Polish man away with her. There was a tear in his shirt.There was a tear in his shirt. There was a tear in his eye.There was a tear in his eye. Words integrated into sentence – meaning clear.Words integrated into sentence – meaning clear. Snowling & Frith (1986): Autism – cannot so readily modify Snowling & Frith (1986): Autism – cannot so readily modify

pronunciation according to contextpronunciation according to context

Impossible Figures & IllusionsImpossible Figures & Illusions

So islets of abilities …So islets of abilities …

Remember all the details of a train Remember all the details of a train timetabletimetable

Rote as opposed to meaningfulRote as opposed to meaningfulGood rote memory should have even Good rote memory should have even

better memory for meaningbetter memory for meaning In autism, good rote memory, poor In autism, good rote memory, poor

memory for meaningmemory for meaning

The case of NadiaThe case of NadiaExecuted highly Executed highly naturalistic naturalistic drawingsdrawings

Local drawing Local drawing strategystrategyWhilst realistic, no Whilst realistic, no sense of sense of imagination or imagination or communicative communicative value of picturevalue of picture

Participant with autism: vma = 7 years (a local drawing strategy)

Typically developing: vma = 7 years (a global drawing strategy)

Central Coherence as Cognitive Style

‘weak’------------------Central Coherence-----------------‘strong’e.g. good proof reading e.g. good gist

recall

A continuum of cognitive style from ‘weak’ to ‘strong’ coherence?

Area of autism risk?

Central coherence & TOMCentral coherence & TOM

Weak cental coherence seems to characterise Weak cental coherence seems to characterise people with autism at all levels of TOM ability people with autism at all levels of TOM ability (Frith, 2003)(Frith, 2003)

So mentalising is a specific, modular ability that So mentalising is a specific, modular ability that is damaged in autism.is damaged in autism.

Two different cognitive characteristics in autism Two different cognitive characteristics in autism – mind-blindness and a cognitive style that – mind-blindness and a cognitive style that favours weak central coherencefavours weak central coherence

Relation between CC and EF?

Executive Functions (EF) = ‘ability to maintain a context-appropriate set for attainment of future goals’

EF deficits found in ASD

EF interpretations of CC findings are possible E.g. inhibitory failure in sentence completion task?

Can EF and CC be disentangled?

Test: ADHD group shows inhibitory problems …

…do they show weak coherence?

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

8 to 10 yrs TD

11 to 13 yrs TD

14 to 16 yrs TD

17 to 25 yrs TD

ASD (11yrs)

ADHD (11yrs)

Performance of ASD and ADHD groups, relative to TD Males’ performance

Impulsive errors on a inhibition task do not correlate with local completions WCC findings not a function of EF problems in ASD

N local completions

Weak central coherence = poor Weak central coherence = poor global processing per se?global processing per se?

Mottron & Belleville (1993) (Navon Mottron & Belleville (1993) (Navon Task)Task)

State the smaller letter (F): slower if State the smaller letter (F): slower if global form incongruent (S) than if global form incongruent (S) than if congruent (F)congruent (F)

State larger letter, response time State larger letter, response time unaffected by incongruity of smaller unaffected by incongruity of smaller letterletter

Experienced interference from global Experienced interference from global to local and not the latterto local and not the latter

Can process global but it does not Can process global but it does not have precedence (deficit in have precedence (deficit in hierarchical organisation)hierarchical organisation)

Heightened processing at a low levelHeightened processing at a low level

Although a devastating disorder, autism is notable for strengths as well as weaknesses

Part of autism may be a cognitive style, not deficit

There may be distinct genetic contributions to this part of autism (vs. social impairment)

Studying cognitive style in ASD should

raise awareness of positive aspects of ASD

increase appreciation of the potential of individuals with ASD

inform educational approaches working to strengths not just weaknesses