what is autism?
a neurodevelopmental disorder with an organic basis because of the sensory and motor and neurological features of autism.
who developed the Theory of Mind?
Baron-Cohen 1985/2005
who developed the Central Coherence Theory?
Happé and Frith, 1989
what has there been emphasis on behind theories of autism?
the emphasis has been on identifying and describing the psychological mechanisms that link the biological substratum and behavioral manifestation of autism.
what is there evidence to suggest that plays an important role in autism?
there is now substantial evidence that an impairment in the ability to recognise that other people have thoughts and that these thoughts are different from one’s own thoughts plays an important role in autism.
what does an absence of mentalisation or theory of mind ability mean for those with ASD?
Absence of mentalisation or theory of mind ability deprives the person with autism of key information about the intentions, motives and actions of other people.
this may account for other aspects of autism such as the apparent failure to integrate lower-level perceptual information into higher-level concepts as described by the central coherence theory of ASD, and possibly the preference for the observable and predictable.
what are the Pervasive Developmental Disorders/ PPD’s?
- autistic disorder
- asperger’s disorder
- childhood disintegrative disorder/ CDD
- Rett’s disorder
- PDD otherwise not specified (PDD-NOS)
What is the Theory of Mind, by Baron-Cohen?
-autistic kids cannot engage in meta-representations, ie. cannot develop ToM
-Problems with ToM ability are manifested in ASD as a central difficulty in understanding and relating to other people, due to an inability to infer the mental state of another person through their speech, actions and non-verbal communication, in particular due to their specific impairments in reading the mind of the eyes, Baron Cohen 2001.
Specific training in using mentalisation techniques has shown but limited success in developing generalisable skills.
Impaired mentalisation is an important factor in disorders such as psychosis, such a direct linkage has not been demonstrated in Asperger’s Syndrome.
…ToM embodies social cognition deficits
what research have Baron-Cohen produced in relation to ToM?
- have difficulty understanding mental state words
- don’t show pretend/ symbolic play
- not aware that eye region indicates thoughts/wants
- unable to deceive
- don’t understand non-literal statements
Executive Dysfunction Deficit, Bola 2007?
executive function: suppression of incorrect response, ability to retain info in working memory, involved in flexible planning.
- Executive functioning has been identified as impaired in ASD, in particular the ability to generate novel responses together with other impairments in planning and shifting attention, Bola 2007.
is there research behind Executive Dysfunction Deficit?
- deficit with frontal lobe, leading to pervasive behaviour
- Executive Dysfunction occurs with other disorders, so by itself it cannot explain autism and may co-occur with ToM deficit
- fails to explain superior skills in certain areas, Savant skills
ASD and memory functioning, in relation to executive functioning?
people with ASD seem to have normal abilities with regard to semantic and procedural memory functioning. they often have difficulties in autobiographical memory functioning, manifesting as an impairment in the spontaneous recall of self-experienced information.
what is the Weak Central Coherence theory, by Happé and Frith, 1989?
- normal people desire a high-level meaning of information, this feature of human processing is disturbed in ASD
- autism is biased towards local information rather than global
- ppl with autism fail to succumb to visual illusions and fail to use context in reading
- Weak Central Coherence theory predicts good performance with attention to local information, recognise object as a single part
- poor performance at recognising global meaning and integration of parts
what are the three complementary theories of autism?
1) Theory of Mind deficit
- social and communication deficits
2) Executive Dysfunction Deficit
- stereotyped behaviours and narrow interests
3) Weak Central Coherence
- special talents and peaks in performance
what sensory problems impact upon people with ASD?
- hyperacusis (which is auditory hypersensitivity),
- tactile oversensitivity
- tactile and somatic under-sensitivity including lower pain threshold
- hypersensitivity to sound, especially high pitched frequencies such as those made by babies, sirens, audible reversing indicators on vehicles, explosions, banging, especially of doors.
- such auditory hyperacusis appears to be a ‘hard-wired’ sensory dysfunction that is not readily amenable,
- Clinical psychology experience indicates that attempts to desensitise people with ASD to such signs throigh gradual exposure may result in considerable distress and is not recommended.
what are characteristics of autism?
- insistence on sameness
- diff in expressing needs like pointing and gestures
- repeating words instead of responsive language
- showing distress for no apparent reason
- prefers to be alone
- difficulty mixing with others
- not liked to be cuddled/cuddle
- little/ no eye contact
- sustained odd play
- inappropriate attachment to objects
- no real fears of danger
- spins objects
- not responsive to verbal cues and act as if deaf when hearing is in normal range
are there genetic tests or biomarkers for ASD?
there are no genetic tests or biomarkers for ASD.
what did Wing and Gould in 1979 develop?
Wing and Gould in 1979 developed the concept of the ‘Triad of impairments’ to describe the presentation of children identified as being autistic.
- The Triad included impairments in communication social interaction and imagination.
- The Triad of impairments have been reconceptualised in terms of lifelong deficits onto dimensions of: social communication and restricted and repetitive behaviour.
how is the severity of the presentation of autism assessed?
the severity of the presentation is recorded for both the social communication and restricted and repetitive behaviours dimensions over three levels, which are:
1) requiring support
2) requiring substantial support
3) requiring very substantial support.
why is autism seen as a fractionated disorder?
Autism is a fractionated disorder; that is the social communication and repetitive and restrictive behavioral elements are possibly genetically separate traits that tend to co-occur, and are not behavioral expressions of a single underlying genetic disorder.
have estimates of the prevalence of ASD has changed?
estimates of the prevalence of ASD has changed considerably over the past 20 years, primarily as a result of changes in diagnostic criteria and also due to professional and public awareness of ASD, resulting in more diagnosis being both sought and made:
2-6 cases per 1000; growing rate of 10-17% per year
4:1 male to female ratio can be observed, in itself an indication of the genetic basis of autism
comorbidity.
ASD comorbidity?
ASD has been positively identified in conjunction with:
- fragile x syndrome (up to 50%)
- down’s syndrome (up to 39%)
- most commonly associated with ADHD, considerable overlap between ASD and ADHD in symptomatology, including impaired social communication and patterns of restricted behaviour and interests, leading up to 28% of children with ASD meeting diagnostic criteria for ADHD.
how do we screen for ASD?
many cases of ASD are potentially identifiable in infancy using instruments such as:
-The Modified CHecklist for Autism in Toddlers, which can be used with infants aged 18 months and above.
-The Infant Toddler Checklist is valid from 9 months upwards.
-The Social Communication Questionnaire can be used on older children aged 5 -11 years.
CHAT/Checklist for Autism in Toddlers
are there early signs of ASD in babies?
further evaluation warranted if:
- no babble/coo @ 12mths
- not gesturing @ 12mths
- not say a single word @ 16mths
- any loss in language or social skills @ any age.
