Autism 1 - Victoria University of Wellington

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Transcript Autism 1 - Victoria University of Wellington

PSYC443: Autism
Session 1
Dr Jason Low
School of Psychology
Victoria University of Wellington
Case 1
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JN at 18 months, did not take delight in engaging in
pretend play and had communication difficulties. He had
a large collection of calculators (he was interested in
numbers). With his collection of toy cars, he was
interested only in placing them in long straight lines in a
particular pattern and was mesmerised with the spinning
of wheels. He often echoed what people said and most
of the time it seemed as if he was looking through
people, not at them.
Case 2
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Stephen Wiltshire born in London. As a child,
was mute and did not relate to other human
beings. Even by age 3, he had no language,
uncontrolled tantrums and lived entirely in his
own world. At the age of five, noticed that the
only pastime he enjoyed was drawing (esp.
buildings). Once, he was taken on a helicopter
ride over the city of London. After a brief ride, he
returns to the ground where, in three hours, he
completes a stunningly detailed and remarkably
accurate drawing of London from the air which
spans four square miles with 12 major
landmarks and 200 other buildings drawn to
perfect perspective and scale
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http://www.youtube.com/watch?v=AxA
R9dnSuQM
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http://www.autismspeaks.org/sp
onsoredevents/autism_every_d
ay.php
Reasons to study atypical
development?
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for PSYC443: as a window through which to
view normal development
 elucidating cognitive processes key to
normal development
Historical perspective
Autism was first described in 1943 by
psychiatrist Leo Kanner. Applied the term
to children who were socially withdrawn
and preoccupied with routine, who
struggled to acquire spoken language.
 Autistic loneliness
 Desire for sameness
 Islets of abilities
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Kanner’s main conclusion
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These children have come into the world
with an innate inability to form the usual
biologically provided affective contact with
people.
Historical Perspective:
Hans Asperger
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Autism was again described
in 1944 by Austrian
paediatrician Hans Asperger.
Applied term to children who
were socially maladroit,
developed bizarre obsessions
and yet were highly verbal
and seemingly quite bright.
Hans Asperger: Case of Fritz
When somebody was talking to him he did not
enter into eye contact fundamental to
conversation
 Normal speech melody was missing
 Stereotypic body movements (e.g., beating
rhythmically on thighs)
 From very early on he had shown an interest
in numbers and calculations
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•
Disturbance of contact existed at some deep level
of affect and / or instinct
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Asperger
Syndrome
Diagnosis in late childhood
or even adulthood
No language delay as
children
Social interaction difficulties
& usually focused
preoccupations (“little
professor”)
Variants of the same
underlying disorder
Neurotypical
Autism
Aspergers
Lessons from history
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Case of the Wild Boy of Aveyron
(named Victor) (found in 1797 near
Toulouse)
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His affections are limited; cares for no
one, and is attached to no one.
He reflects on nothing. His imbecility is
evident in his gaze.
The most harmonious sounds make no
impression on his ear (but is sensitive to
opening of the cupboard containing
walnuts).
Indifferent to all childish amusements.
Educating Victor
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Jean-Marc Itard in 1801
took on the task of Victor’s
education
Showed some acquisition
of sign language and a few
words (milk, oh god)
Never learned the meaning
of social values (“a true
idiot”)
Victor and autistic loneliness
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“Mme Recamier seated Victor at her side,
thinking perhaps that the same beauty that
had captivated civilised men would receive
similar homage from the child of nature,
who seemed not yet 15 years old. Too
occupied with the abundant things to eat,
which he devoured with startling greed as
soon as his plate was filled. When dessert
was served, and he had filled his pockets
with all the delicacies that he could fetch,
he calmly left the table. Suddenly a noise
came from the garden. We soon glimpsed
Victor running across the lawn with the
speed of a rabbit. To give himself more
freedom of movement, he had stripped to
his undershirt. Reaching the main avenue
of the park, climbing the nearest tree with
the ease of a squirrel, he perched in the
middle of the branches.”
The Mother’s dilemma
Autism Triad
Social
deficits
Imaginative
Deficits
Communication deficits
Yes
Epidemiology
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Rates in studies between 1966 and 1991: 4.4
cases per 10,000 (Wing & Potter, 2002)
Rates between 1992 and 2001: 12.7 per
10,000 (Fombonne, 2003)
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Epidemic of autism?
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Changes in diagnostic practice?
Increased awareness?
Earlier diagnosis
Issues of study design & case ascertainment
Epidemiology
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Boys disproportionately affected (ratio 3.4
or 4.0 to 1; Frombonne, 2003; Volkmar et
al., 1993)
Possible that males have lower threshold
 More severe neurodevelopmental
abnormalities needed in girls
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Organic Context
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Concordance rates for MZ twins (36%91%) higher than compared to DZ twins
(0%) (Bailey et al., 1996)
Elevated level of serotonin (chemical
messengers) in 25% of individuals with
autism (Klinger & Dawson, 1996)
Structural abnormalities in limbic system
(emotion), amygdala (social cognition),
and areas of cerebellum (sensori-motor
integration) (Bauman, 1996)
 Dawson (2001): 3- and 4-year-olds
reactions to neutral and fear depicting
photos. Brain activity of autistic
children didn’t change in response to
the different images.
Need to ask whether it is specific brain
damage or a disorder of development
The Great Vaccination Scare
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Sudden increase, blame novel environmental agent
(e.g., vaccination)
First signs of autism noticed at 2nd year
Proportion of cases show regression
Proportion of cases have severe gastric conditions
So MMR vaccination = autism?
Evidence?
 Meaning of increasing number of cases
 Number of cases diagnosed in relation to introduction
of MMR in various countries?
 Difficulties in diagnosing in first year of life
Difficulties in Diagnosis
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DSM-IV (1994) – Autism
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A total of six (or more) items from impaired
social interaction, and one each from impaired
communication and impaired imagination, and
onset prior to 3 years of age
Often, earliest signs go unnoticed
 Problems arise with borderline cases
 Additional problems that may overshadow
autistic features
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Difficulties in diagnosis
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Knobloch & Pasamanick (1975): 50 children
identified with “failure to regard people as
persons” – compared to 50 controls
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Followed up 3 to 10 years later
Those seen before 12 months – failure to regard
people as persons disappeared
Those seen in the second or third year were definitely
diagnosed as autistic later on
What facts can be learned from the above example?
What happens in adulthood?
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The disability does not go
away
But through treatments (e.g.,
behavioural learning, language
training, physical props to
mental states), improvements
in adaptation and behaviour
can be observed
Can be guided into a niche
where skills are put to good
use
But future of any child with
autism remains uncertain, as
with any child
a disorder of unknown cause
From here on …
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Theoretical (and associated methodological)
approaches to studying the autism triad
Theory of Mind (Mindblindness)
Executive (Dys)Functioning
(Weak) Central Coherence
Do these approaches highlight domain specificity issues,
or are they interacting?
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Where and how does language fit in?