Autism Spectrum Disorder (ASD)

ASD characteristics: disorder type, symptoms (2), onset, duration

• Complex neurodevelopmental disorder

• Challenges in social interaction + communication

• Stereotyped (repetitive + non-goal directed) behaviours + interests

• Present in early life

• Life-long

How diagnosed (1)

• No biological markers so based on behaviour

DSM-5 criteria (5, A - E)

• A. Deficits in social communication + interaction (all 3)

• B. Restricted, repetitive patterns of behaviour, interests, or activities (at least 2)

• C. Onset: Symptoms present in early developmental period

• D. Impairment: Clinically significant in functioning

• E. Exclusionary

• A. Deficits in social communication + interaction: symptoms (3) w/ examples

Deficits in all 3 of:

• Social-emotional reciprocity (social exchange)

  • Difficulty maintaining conversations, responding to social interaction, emotional sharing

• Non-verbal communication behaviours

  • Atypical eye contact, difficulty understanding gestures

• Developing, maintaining + understanding relationships

  • Difficulty adjusting behaviours to suit context (e.g. playground vs classroom), no interest in forming friendships

• B. Restricted, repetitive patterns of behaviour, interests, or activities (4)

Deficits in at least 2 of:

1. Stereotyped or repetitive motor movements, use of objects, or speech

2. Insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal behaviour

3. Highly restricted, fixated interests that are abnormal in intensity or focus

4. Hyper- or hypo-reactivity to sensory input or unusual interest in sensory aspects of environment

C. Onset (1)

Symptoms must be present in early developmental period

D. Impairment

Symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning/in daily life

E. Exclusionary (1)

Disturbances not better explained by intellectual disability or global developmental delay

Specifiers description + 3 levels

• Used to indicate severity level of disorder

• Level 1: requiring support

• Level 2: requiring substantial support

• Level 3: requiring very substantial support

Prevalence of ASD: % of population, male:female

• ~1% population

• 3:1 male to female ratio

Early signs (4) + regression

• Lack of social reciprocity

• Restricted eye contact

• Not responding to name

• Limited speech

• Minority of cases → regression can occur (normal dev then ‘regress’ to ASD symptoms), but normally present in early dev.

Dimensional approach to understanding ASD (1→1), “rainbow of traits)

• View: there is a continuum of ASD traits in general pop. (normally distributed)

  • Autism Spectrum Quotient (AQ): questionnaire used to measure characteristics of mild autism traits in general pop. (ASD individuals score higher on this)

• Rainbow of traits: autism is "a collection of related neurological conditions that are so intertwined and so impossible to pick apart that professionals have stopped trying"

ASD strengths: approach, morals, values, skills, expertise

• Attention to detail + thorough/systematic approach

• Strong sense of morality + honesty

• Trustworthiness, loyalty, kindness

• Artistic skills

• Expertise in specific areas (maths, creative)

Biological factors: specific genes, heritability

• No specific gene/s associated yet (likely a range)

• Strong genetic component

Biological differences: head circumference, brain size, neuron numbers, neural connections

• Abnormal growth in head circumference in infancy

• Overall brain size 2-10% larger

• Fewer neurons in amygdala, hippocampus, anterior cingulate, and cerebellum

• More interconnectivity within certain areas → specific expertise, less interconnectivity across areas

Influences in prenatal + postnatal environment that increase ASD susceptibility

• Parental age

• Low birth weight

• Multiple births

• Maternal infection

Cognitive theories to explain behavioural aspects of autism (3 main, 5 others)

• Deficits in Theory of Mind (TOM)

• Weak central coherence

• Executive dysfunction

• Limited inner speech (thinking in pictures)

• Systematising/empathising

• Context blindness

• Monotropism

• Double empathy theory

Deficits in Theory of Mind (TOM): TOM def, false-beliefs tasks, limitations (2)

• Ability to attribute mental states to self/others

• Fail false beliefs task even at age 11 (high-functioning individuals may pass)

• Deaf + ID populations also fail false beliefs test

• Can’t explain all features of ASD well

Weak Central Coherence (WCC): description, how explains ASD, benefit, note

• Difficulty using context to form parts into an integrated whole: analytic processing (parts), as opposed to holistic (context)

• Weak CC explains limitations such as not using context to disambiguate information (e.g. difficulty w/ irony/humour)

• Benefit/strength: superior performance on tasks where processing by parts is an advantage

• Revised theory: suggests preference (not impairment/need) for processing by parts

Executive dysfunction: def, example of evidence, what it explains, limitations (2)

• Higher-level processes responsible for goal-directed action

• Deficits in EF of ASD individuals:

  • Difficulty switching to sorting by different category after doing one category

• Can explain repetitive behaviours and cognitive inflexibility

• Doesn’t explain social features well

• Not autism specific

Cure/lack, shifting perspective, alternative approaches (2)

• No known cure

• Shift towards viewing as condition rather than disorder (difference rather than deficit)

Rather than changing autistic person:

• Changing environment to accept/support autistic people

• Enhance person-skills environment fit

Goal of intervention strategies (3)

• Reduce risk to self/others

• Reduce challenging behaviours

• Improve social + life skills

Evidence based approaches to ASD management (5)

• Structured learning + increasing routine/predictability

• Breaking goals/tasks/instructions into small steps

• Positive reinforcement

• Direct instruction, modelling of social situations + coaching

• Promote generalising (applying skills to other situations)

Best practice for principles of early intervention (5) *not vital to know

• Begin early (2-4 years)

• Family involvement

• Multi-disciplinary approach

• Individualised approach

• Support for transition to school