Autism Spectrum Disorder (ASD) Flashcards
ASD was not described until
1940s
What are the DSM-5 Diagnostic Criteria for ASD?
o Deficits in social emotional reciprocity
o Deficits in nonverbal communication
oDeficits in developing, maintaining relationships
o Stereotyped, repetitive movements, speech, etc.
o Insistence on the sameness of routines of rituals
o Fixated interests of unusual intensity or focus
o Hypo or hyper activity to sensory input
what are some Stereotyped, repetitive movements, speech, etc. seen in ASD
→ Lining up/stacking toys in the same way over and over
→ Echolalia – repeating what other people say
→ Idiosyncratic phrases that are repeated frequently
how are ASD kids Hypo or hyper activity to sensory input
→Apparent indifference to pain, temperature
- self injury (banging head)
→Adverse response to specific sounds, textures, etc.
- bright lights, loud noises disturb them
→Excessive smelling, touching of objects
- Unusual ways of exploring objects (tactile), also towards people
ASD kids have the Highest level of comorbidity with what other disorder?
intellectual disability (formally called retardation)
What are some specifications for ASD
o With or without intellectual impairment or language impairment
o Associated with medical, genetic, environmental conditions
o Associated with another mental, behavioural disorder
o With Catatonic Excitement: excessive movement – slightly resembles hyperactivity in ADHD
What is APA treatment?
o Training the individual to use language (linking words with objects)
what are some associated features of ASD not necessary for diagnosis?
- Intellectual and/or language impairment
- Motor deficits
- Self-injury
- Disruptive or challenging behaviours
- Prone to anxiety, depression (adolescents or adults)
In what type of ASD is self injury most common?
o In the lower 40-50% it is very prevalent to the point where bones are broken
prevalence of ASD according to DSM-5?
100/10,000 = 1%
list the increase in prevalence (2003-2010) By Age.
o In 2-4 yr olds: 170% increase
o In 5-9 yr olds: 108% increase
o In 10-14 year olds: 204% increase
list the increase in prevalence (2003-2010) By Sex.
o Boys: 142% increase
o Girls: 161% increase
between 1987 and 1998 there was a ____% increase in prevalence
270
Why was there such a large increase in the prevalence of ASD?
• Increased awareness • Earlier Diagnosis (1 or 2 yrs) • Changes in diagnostic practice • Diagnostic substitution (kids with ASD were labeled as having only intellectual disability) • More Environmental toxins = more cases
What is the sex bias in ASD
• 4-5 times as common in boys than girls
Where is the lowest male/female ratio?
extreme low range of cognitive function
where is the highest male/female ratio?
normal range of cognitive function
____% of ASD will meet criteria for another disorder, ____% will meet two or more
70%, 40%
What disorders is ASD comorbid for? (%)
→intellectual disability: 70%
→ Anxiety of phobic disorder: 42%
→ ADHD: 40%
→ Opposition defiant Disorder: 28%
What psychological processes do ASD kids excel at?
o visuo-spatial processing
o Attention to detail
o Rote memory
What are savant abilities, who develops them?
o An island of special ability in a sea of deficits
- the lower half of the autism spectrum, in as high as 10%
What are some examples of savant abilities
o Mathematics, esp. rapid calculation
o Music – very quickly learn an instrument and repeat a musical piece after having heard it just once
o Calendar calculations
What are 2 hypothesis about savant abilities?
1) Whatever the diathesis deficits are also code for savant talent
2) We all have these abilities but they are somehow shutdown by our normal neurodevelopment
What are some motor development problems and the percentages associated with each?
- 60% = dysdiadochokinesia (Trouble with rapid alternating movement)
- 33% = Problems with gait or balance
- 15% = abnormal muscle tone
- 5% = abnormal reflexes
- 5% = Abnormal motor coordination
What is the Theory of mind view of ASD?
Deficit in understanding mental states
→States of Knowledge or ignorance
o can’t know what other people know/don’t know
→ Have difficulty understanding Pretense, deception and lying
→ Trouble with jokes, irony and sarcasm
What are some criticisms of the theory mind view of autism?
→ Social impairment before precursors of ToM
o showing symptoms in infancy before ToM develops
→ ToM & communication emerge independently
→ ToM found in High functioning autism
→ ToM deficits in mental retardation (not specific to autism)
What are some abnormalities ASD kids exhibit when perceiving faces/emotions?
o Sort faces by physical features not emotions
→ difficulty sorting by emotion
o scan faces by looking at the exterior of the face
o ERP differences between familiar/unfamiliar objects, not faces (mother vs. stranger)
o Superior temporal gyrus activates during face perception (the same area that TD kids use to process objects)
What is the extreme male brain theory of ASD?
Males=systematizers, females=empathizers.
ASD kids have extreme male brain, explains lack of empathy and insistance on routine
What evidence supports the extreme male brain theory?
→Parents of autistic children (POA) faster on embedded figures test
• POA are more likely to have systemizing fathers
• POA show male patterns of brain activation
• POA higher on self-reported autistic trait
• 2 systematizing parents = higher chance of having a child with autism
What is the intense world theory of ASD?
o Hypersensitivity to stimulus = meaning there is hyperactivity in the brain
o Autism = extreme introversion to
cope with choas
o Brain has too many connections
o Amygdala (overactive) = rapid conditioning of fear
o High intra-connectivity, low inter-connectivity
In what ways do ASD kids cope with internal choas?
• Social withdrawal = language decrement
• Repetition, stereotypy = controlling chaos
• face perception problems
→ They have difficulty organizing the multiple stimulations that arise from perceiving a face
• fear of world & withdrawal
WHat research has been done with Valproic acid
VPA in pregnant women = increased risk of ASD (10%)
VPA in rat puppies = brainstem damage, social withdrawal, hyper reactive to stimuli, more cortical cells and connections (higher arousal)
What are the 2 types of empathy?
- Cognitive (CE) = understanding others’ epistemic mental states (same as ToM)
- Emotional (EE) = Feeling what others feel as a result of other’s emotions
What is the Empathy imbalance hypothesis?
o Autism = High EE, deficient CE
o Autistic symptoms (withdrawal) = protection from intense empathic emotions by avoiding social interaction.
What evidence supports the empathy imbalance hypothesis?
- ASD kids = more facial affect than other in an empathy arousal paradigm study.
- Adults with autism show more facial EMG when shown expressions of happiness, fear
- look away from images images of distressed people
- Asperger’s adults report high levels of distress to others’ suffering
- eye contact with others is “painful” for people with autism
What are some problems with the empathy imbalance hypothesis?
→ What about high comorbidity with mental retardation
→ What about language development and idiosyncratic language
→ What about face-processing deficits
→ What about early eye-tracking data, and cuddling failure (how is this related to empathy imbalance since empathy doesn’t develop until 2 years old)
list the 5 theories of autism
• Theory of mind • Intense World theory • Extreme Male Brain Theory • Empathy Imbalance Hypothesis • Executive Function Theory (deficits in function in the prefrontal cortex)
what are the 3 major deficits in autism?
- Social Cognition (Face recognition, Emotion processing)
- Language and communication
- Motor behaviour and coordination
What are mirror neurons?
They get active when we perform some kind of behaviour
→ Also become activated when someone else does the exact same behaviour
• ASD kids have problems in mirror neuron functioning
→ Only fire for own activity, not for others
What brain areas have fewer cells/ fewer dendritic connection in ASD?
Amygdala, Cerebellum, Prefrontal cortex (also has lower bloodflow), Temporal lobe
What are some size differences in brain areas of ASD patients?
o Reduced corpus callosum size (long range interconnectivity)
o Brain volume and ventricle volume is larger = large head circumference
What happens in language areas of ASD kids
→ Reduced activity between areas during language processing
FFA and ASD?
→ Abnormal FFA activity (temporal lobe) in face perception
what is the rate of seizures in autism, who gets them?
o High rate (33%) of seizure acidity
→ More frequent in females (because they are typically at the lower levels)
what percent of ASD kids show abnormal EEG results?
o EEG abnormalities in 50% of ASD kids
Excessive connections in _______ and too few with the __________
Frontal cortex, rest of the brain
What neurotransmitters have been linked to autism?
DOPAMINE
o Role of dopamine in movement problems
o Dopamine-blocking agents
SEROTONIN
•Elevated blood levels of serotonin in 33% of autism patients
o Synthesis of serotonin rises to 150% of normal adult level between ages 2 and 15 years old
What are the concordance rates of ASD as shown through twin studies?
o MZ concordance = 65-75% (0.9)
o DZ concordance = 3-10% (0.5)
what genetic conditions is autism associated with?
o Fragile X syndrome, PKU, Congenital rubella (German measles)
o Chromosome 15 duplication
Social/communication impairments are found in __% of siblings of ASD
20
What is Pleiotropy?
o Genes that code for heightened risk of autism also confer susceptibility to other disorders (depression, schizophrenia)
Parents of children with ASD also have higher probability of having what disorders?
Anxiety, depression, substance abuse
how many chromosomes have been implicated in ASD
15 of 22
What are some environmental risk factors associated with ASD?
- Maternal smoking in 1st trimester
- Caesarian delivery (conditions that make it necessary)
- Baby small for gestational age
- Older fathers
- Maternal prenatal exposure to pesticides or air pollution
- Prenatal German measles infection (rubella)
- Mother not born in Europe or North America ( do not have built in immunity to viral infections)
- Summer conception
What are some treatments of ASD?
• Applied Behaviour Analysis • Teaching social skills (high functioning cases) • Pharmacotherapy o Tranquillizers (Neuroleptics) and Antidepressants
