ASD Flashcards
what is ASD?
a neurodevelopmental disorder defined by sig diffs in 2 areas:
- social communication/ social interaction
- restricted and repetitive behaviors/interests/ activities (RRBs)
*need sympts in both domains for diagnosis
social communication/ social interaction
may be indiff to physical contact, make little/no eye contact, infrequent gestures, limited facial expressions used, isolated and unimaginative play
- may not respond to others’ emotions, uninterested in making friends
- tendency to focus on parts of faces rather than face as a whole
- may not imitate others (in neurotypical this is the norm)
restricted and repetitive behaviours/activities
repetitive movements (hand flapping) and use of objs, insistence on sameness (lining toys up specifically) and if disrupted, provokes extreme distress; narrow interests
- echolalia: repeat words back
- extreme responses to sensory input (sounds like a vacuum, textures for clothing, smells)
DSM criteria
persistent deficits in social communication and social interaction across multiple contexts
- 2+ markers of RRBs
- symptoms present from early childhood; specific symptoms/characteristics are noted using specifiers (if assoc w/ medical/genetic condition) and modifiers (if there is also intellectual disability)
early atypical autism spectrum disorder
intended to identify children 9-36 months who do not meet diagnostic criteria for ASD but have sig symptoms and impairment
associated characteristics
cognitive
language
motor
behavioural
physical/health
assoc characteristics: cognitive
30-40% have intellectual disability; diffs in exec functions common (struggle w/ planning/ organization, problem solving)
- central coherence: refers to tendency of humans to interpret stimuli in a global way and takes broader context into account (ppl w/ autism don’t really do this, they process in small pieces rather than look at whole picture)
assoc characteristics: language
35-40% do not develop communicative speech; lang may be marked by echolalia, pronoun reversal, unusual information (putting emphasis in diff places can make it hard to understand speech)
assoc characteristics: motor
50-80% have difficulties w/ gross motor skills (doing up buttons, holding pencil), fine motor skills, or co-ordination or balance
assoc characteristics: behavioral
about 30% show self-injurious behs (more likely w/ comorbid intellectual disability)
- head banging, excessive skin scratching or rubbing
assoc characteristics: physical/health
probs w/ sleep (frequent awakenings) and/or eating (can lead to high rate of gastric probs, stomach pain, nausea), about 25% develop seizures (more likely later in adolescence or young adulthood)
prevalence rates
2-3% of children in general pop; Canada 2019: 2%; Global 2022: 1%
- higher estimates now because there is a lot more awareness of symptoms, broader diagnostic criteria, and better detection
sex differences
more common among boys (4:1)
- core symptoms are the same; girls may show fewer RRBs and higher scores on lang skills and social motivation
- girls appear to be diagnosed at lower rates and diagnosed later in life
when do symptoms emerge, and what is avg age at diagnosis?
symptoms emerge during first 1-2 yrs of life; reliable detection at 12-18 mos, reliable diagnosis by 24 mos (used to be 36mos)
- avg age at diagnosis: 4yrs
- symptoms may show up b/t 6-12mos of life, prefer unusual objs, looking at diff angles, squinting a lot
symptom pattern over childhood
- preschool: classic symptom pattern
- school age: more responsive socially, but odd behs and self-stimulation/injury more common
- adolescence: symptoms continue, hyperactivity and self-injury may worsen, some make dev. gains, others don’t
symptom pattern in adulthood
symptoms, associated characteristics may improve, but diagnostic stability is high, ASD is lifelong condition
Simonoff et al. (2020) changes from 12-23yrs
youth followed from 12-23yrs: ASD symptoms remained the same, IQ increased (by 7+ points, huge inc), linked to higher language level in childhood
etiology
a biologically based neurodev disorder that involves genetic and enviro factors
bio factors
- family, twin, gene studies show sig heritability (up to .80), likely involving single and multiple gene mutations
- larger brain volume, specific structural abnormalities (frontal, amyg, cerebellum), dec blood flow in some regions (frontal, temporal), disrupted connectivity among brain regions, inc white and grey matter
enviro factors
gene expression is affected by enviro factors before, during, and/or after fetal brain dev (older parental age, meds, drug exposure, low birth weight
early interventions are used to…
reduce/minimize impact of core diffs, maximize independence and quality of life, help the person and fam manage diagnosis
best early intervention
highly structured skills-oriented strategies have shown the most success
- esp when tailored to child
- provide educ and support to fam
- some children also given antipsychotic meds to help reduce challenging behs
- maximize child’s independence and QOL
best intervention features include
- early
- intensive
- low student-to-teacher ratio
- high structure
- fam inclusion
- peer interactions
- generalization
- ongoing assessment
3 things we have learned from prospective longitudinal studies of infant siblings of children who have been diagnosed with ASD
1) recurrence risk of ASD in infant siblings = up to 20% (10X higher than prevalence of ASD)
2) many behavioral markers emerge around 12 months (sometimes earlier); social abilities before 12 months do not rule out development of ASD
3) high risk siblings who do not develop ASD by 36 months may have other dev challenges (cog/lang delay)
identify any 4 myths that persist about autistic individuals
- children “grow out” of autism (it is lifelong)
- they don’t have emotions (they are just not expressed as expected)
- caused by vaccinations
- they are all geniuses in science fields (many w/ avg intelligence, and in other fields; about 10% are extraordinary)
