Autism Spectrum Disorder Flashcards
What are the characteristics of autism?
neurodevelopmental disorder
emerging in infancy
onset peaks in early childhood
broad range of impairment and intellectual disability
What are the persistent deficits in social communication and interaction seen in autism?
social-emotional reciprocity
non-verbal communication
developing, maintaining, and understanding relationships
What are the restricted and repetitive patterns of behavior in autism?
stereotyped or repetitive motor movements
inflexible adherence to routines
restricted and fixated interests
hyper or hypo-reactivity to sensory input
How is autism spectrum disorder described in the DSM-V?
DSM-V is the first edition to characterize autism as a true spectrum disorder, condensing many previous categories of developmental disorders
What are the DSM-V categories of autism spectrum disorder in the DSM-V from minimal support to very substantial support?
autistic savant
pervasive developmental disorder (NOS)
Asperger’s syndrome
Autism
autistic disorder
childhood autism
infantile autism
childhood disintegrative disorder
What are the disorder associated with autism spectrum disorder in the DSM-V in order from minimal support to very substantial support?
Fragile X syndrome (female heterozygous)
Fragile X syndrome (male)
Rett syndrome
What are the deficits in social-emotional reciprocity in children with ASD?
little initiation of social interaction
absence of sharing of emotions
reduced or absent imitation
language use (if present) restricted to requests rather than commentary or conversation
What are the deficits in social-emotional reciprocity in adults with ASD?
difficulty processing social cues
struggle in novel social situations
What are the deficits in non-verbal communicative behaviors in children with ASD?
reduce or absent eye-contact
impaired joint attention: pointing or following pointing, showing or bringing to share interest
What are the deficits in non-verbal communicative behaviors in adults with ASD?
compensatory social behaviors
wooden or exaggerated body language
poor integration of eye contact, gesture, posture, facial expressions
What are the deficits in developing and maintaining relationships in children with ASD?
absent or reduced social interest
lack of shared and/or imaginative play
insistence on play by fixed rules
What are the deficits in developing and maintaining relationships in adults with ASD?
struggles with situational differences in appropriate behaviors
struggles with language use: irony, white lies, sarcasm
preference for solitary activities
“incomplete” friendships: one-sided relationships, friendships solely based on s shared interest
What are repetitive behaviors in ASD?
vary according to age and ability
simple motor stereotypes: hand flapping, finger flicking
repetitive use of objects: spinning coins, lining up toys
repetitive speech: echolalia, use of “you” in self reference
ritualized patterns of behaviors: pacing, repetitive questioning
adherence to routines/resistance to change: distress at small changes, insistence on rules, rigidity in thinking
restricted and fixated interests: child preoccupied with vacuum cleaners, adults spending time writing out timetables
fascinations or aversions related to sensory input: aversion or fixation to sounds, smells, tastes, or textures
What are the associated features of ASD?
intellectual impairment (>60%)
language impairment
motor deficits
self-injury
anxiety and depression in adults
seizures (25%)
What are the DSM-V specifiers of ASD?
severity: graded from 1 (requiring support) to 3 (requiring substantial support)
accompanying intellectual impairment
associated with a known medical condition or environmental factor: Rett, Fragile X, or down syndromes, epilepsy, fetal alcohol syndrome, valproate exposure
What is prevalence of autism?
higher prevalence in males (2:1 for ASD or 4:1 for Asperger’s)
current estimates range from 0.2-1.4% (1 in 68 in US data)
oft-quoted “historical” prevalence of ASD is 0.04% (4 in 10,000)
What are the two hypotheses to explain observed increases in rates of ASD?
rates of autism are increasing due to the influence of an as yet unidentified environmental factor
diagnoses of autism are increasing due to increased awareness, surveillance, and therapeutic support
What is the vaccine hypothesis of ASD?
diagnosis of autism have increased since the introduction of the measles-mumps-rubella vaccine in 1971
age of appearance of autistic symptoms correlates with age of vaccination
What is the controversy of the vaccine hypothesis?
exhaustive meta-analyses demonstrate no changes in rates of autism relating to MMR
Wakefield was shown to have multiple conflicts on interest, manipulated evidence, and broke rules of ethics in his research
study retracted partially 2004, fully 2010
Wakefield prosecuted for serious professional misconduct and struck off the UK medical register
What is the gastrointestinal hypothesis of ASD?
gastrointestinal problems associated with dietary gluten have been proposed to contribute to development of autism
open-label studies promoting gluten-free diets for autistic patients have shown improvement of symptoms
specific GI problems are not identified as a common comorbidity in children with autism: rates comparable to the general pediatric population
testing for general gluten-sensitivity is not available: studies examining celiac disease show no apparent interaction with autism
the only blinded study of gluten tolerance showed no relationship between improvement in autistic symptoms and gluten intake
What is the diagnostic hypothesis of ASD?
criteria for a diagnosis of autism have been redefined several times since 1960s
rates of autism are comparable across cultural and international borders
rates of ASD among adults (including those born before 1971) are comparable to children
increased rates of autism in the US from 1994-2003 correlate with declines in other diagnostic categories (e.g. mental retardation)
retrospective analyses using current diagnostic criteria on historical datasets suggest comparable rates
availability of services and public awareness (e.g. de-stigmatization) have helped increase diagnoses
What is the onset and development of ASD?
autism is usually diagnosed by 3 years of age: prospective studies show deficits in social responsiveness and communication are observable by 6-12 months
regression in ~25% of ASD cases: absent in Asperger’s
characterized by delays in development, with varied outcomes
not progressive beyond developmental periods
often fairly responsive to behavioral interventions: early intervention improves treatment efficacy
What are the common psychiatric co-morbidities of ASD?
anxiety
depression
obsessive-compulsive disorder
What are the common psychiatric co-morbidities in parents of children with ASD?
anxiety
depression
What are the historical perspectives on ASD?
intellectual disabilities have been aggressively persecuted
ancient Spartans threw “defective” babies from a cliff
British mental deficiency act (1913) placed those with mental retardation into custodial care
US supreme court (1927) upheld forced sterilization for mental retardation
Alberta sexual sterilization act (1928) amended in 1937 to allow sterilization without consent for those deemed mentally defective (until 1972)
What is the “refrigerator mother” theory of ASD?
Leo Kanner, who first described autism in 1943, put forward the idea that autism was affected by maternal behaviors
Bruno Bettelheim popularized the idea that autism was caused by mothers who did not communicate properly and withheld affection from their children in the 60s-70s
Bernard Rimland proposed a neurological basis for autism in his 1964 thesis and led the foundation of the Autism Society of America
What is the empathizing brain?
drive to identify another’s thoughts and emotions
prediction of behavior of individuals
involves speculation about affective states
What is the systemizing brain?
drive to analyze variables and construct systems
predict behavior of systems
detail/process oriented
What is the “male brain theory” of autism?
balance between empathizing and systemizing define the stereotypic gender differences
female (E > S)
male (S > E)
autism (S»_space; E)
What are the genetic causes of autism?
heritability estimate up to 90%
20-50x increased risk of a second child having autism
60-90% concordance in monozygotic twins
10% concordance in dizygotic twins
What are the specific genetic syndromes that cause autism?
Fragile X syndrome
Rett syndrome
tuberous sclerosis
duplications at 15Q1-Q13
What are the environmental causes of autism?
fetal alcohol exposure
fetal valproate exposure
