Intro to atypical development Flashcards
1
Q
broad definition of development
A
- study of change and stability over the lifespan
- how we change physically, cognitively, behaviourally and socially
- due to biological, individual and environmental differences
2
Q
what do we need to remember about language (when describing atypical development)
A
- do not always need to be negative
- recognise them as differences not deficits
- diversity is important
- use terms like ‘condition’ and ‘difference’
- listen to ‘experts-by-experience’
- autistic people have led the change
3
Q
person first vs identity first language
A
- person first = ‘person with autism’
- identity first = ‘autistic person’
4
Q
what is the gold standard for testing atypical development?
A
- two control groups
1. one matched to atypical group’s chronological age
–> if perform worse than this group (only) there is a delay
2. one matched to atypical group’s mental age
–> if perform worse than both groups could be a delay or a difference
5
Q
reasons for atypical development
A
- Pre-natal effects
–> e.g. exposure to teratogen
–> fetal alcohol spectrum disorder - Environmental effects
–> e.g. complications during birth
–> cerebral palsy - Genetic effects
–> e.g. hereditary
–> e.g. spontaneous mutations (like copy number variants) - Unknown (like multifaceted effects)
–> Autism
–> ADHD
6
Q
developmental conditions with a known GENETIC cause
A
- William’s Syndrome
- Down’s Syndrome
- 16p.11.2 (example of a CNV)
7
Q
developmental conditions with a known ENVIRONMENTAL cause
A
- Fetal alcohol spectrum disorder (FASD)
8
Q
developmental conditions with UNKNOWN causes (probably multifaceted)
A
- Autism spectrum conditions
- ADHD
- Intellectual disability
9
Q
basic genetics
A
- every cell has DNA
- DNA has instructions for how to build proteins
- basis for our development
- structure and function of the body is governed by the types and amounts of proteins the body synthesizes
- DNA is packaged into genes and humans have approx. 21,000 TYPES of genes
- genes are contained in chromosomes (each chromosome contains 100s to 1000s of genes)
10
Q
very basic map of genes
A
DNA –> genes –> chromosome –> cell
11
Q
how do we label parts of the chromosome?
A
- chromosome arm = each chromosome has a short arm (p for petite) and a long arm (q)
- chromosome region = regions are labelled with numbers
–> lower numbers are those closest to the centre
12
Q
chromosomal abnormalities that can lead to atypical development
A
- genetic abnormalities can occur when there are too many or too few occurrences of particular genes
–> can have an extra chromosome (e.g. Down’s Syndrome have an extra 21 chromosome)
–> other people can have parts of their chromosomes duplicated or deleted
13
Q
brief examples of atypical conditions due to genetic abnormalities
A
- Down’s Syndrome = extra chromosome
- 16p.11.2 = duplication of a certain part of a chromosome
- William’s Syndrome = deletion of a part of a chromosome
14
Q
what is 16p.11.2?
A
- depletions and duplications of 16p.11.2 have come under scrutiny due to their association with a range of developmental conditions:
–> ADHD
–> Autism
–> Anxiety
–> OCD - can have more (duplication) or less (deletion) of certain genes
15
Q
different variations of 16p.11.2 presentation
A
- leads to developmental delay, autism or intellectual delay in some
- on others it remains undetected due to no physical or developmental symptoms
- generally only detected when children come to clinic with signs of developmental delay and autistic features
–> can be very very hard to detect
16
Q
duplications vs deletion of 16p.11.2
A
- have similar links to autism, ADHD and intellectual disability
- also have their differences
–> deletion = obesity and larger heads
–> duplication = schizophrenia and bipolar disorder
17
Q
overview of William’s Syndrome
A
- caused by spontaneous deletion at chromosome 7q11.2
- always a deletion
- very specific cause every time (same deletion at same arm and region)
- characterized by:
–> distinct facial appearance
–> cardiac anomalies
–> highly sociable personality
–> atypical cognitive profile
–> connective tissue abnormalities - very rare (approx. 1 in 10,000)
18
Q
cognitive profile of William’s Syndrome
A
- can do IQ tests and other cognitive tasks to test them
- need to remember individual differences exist
- tend to have very good language abilities
–> great verbal, descriptive and conversational ability - struggle in their visuospatial IQ/ability
–> e.g. can describe an elephant perfectly but struggle to draw an elephant and represent it visually
19
Q
what causes Down’s Syndrome?
A
- always a duplication
- always a duplication of chromosome 21
- doesn’t have to be a full duplication
–> doesn’t have to be a perfect replication
–> can be partial
20
Q
physical characteristics of Down’s Syndrome
A
- individual differences
- but some common traits:
–> Decreased or poor muscle tone
–> Shorter neck
–> Flattened facial profile and nose
–> Upward slanting eyes
–> Wide, short hands with short fingers
–> A single, deep, crease across the palm of the hand
21
Q
cognitive
characteristics of Down’s Syndrome
A
- individual differences
- some common causes:
–> Short attention span
–> Impulsive behavior
–> Slow learning
–> Delayed language and speech development
–> Variable IQ (average between 30 -70, neurotypical tends to over 100)
22
Q
mechanisms of fetal alcohol spectrum disorder
A
- alcohol is a teratogen
- ethanol is thought to alter DNA and protein synthesis
–> also inhibits cell migration which leads to physical and cognitive changes - no clear on the amount of alcohol needed to lead to FASD
–> can depend on when the alcohol is consumed
–> binge drinking leads to more severe symptoms - more prevalent than what we think
–> once reached 2-3% prevalence in Canada
23
Q
what is a teratogen?
A
agent that causes changes in an embryo
24
Q
some diagnostic criteria for fetal alcohol spectrum disorder
A
- hard to pinpoint and diagnose
- overlap with ADHD for example
- some criteria:
–> hyperactive
–> attention difficulty
–> poorer memory
–> struggle in school
–> low IQ or intellectual disability
–> poor reasoning and judgment skills
–> problems with heart, kidneys or bones etc…
25
what is intellectual disability?
- is a diagnosis on its own
- often co-occurs with other neurodevelopmental conditions (e.g. Autism or FASD)
- affects approx. 10.4 people in every 1000 (1.4%)
- diagnosis is based on IQ evaluation as well as investigation of adaptive behaviour
--> classified as mild (52-69), moderate (36-51), severe (20-35) or profound (<19)
26
different domains of diagnosing intellectual disability
1. conceptual
--> academic success
--> planning
---> executive functioning
2. social
--> friendships and relationships
--> communication
3. practical
--> coping in their day to day life
- need a rounded picture of the individual
- no genetic testing so need battery of tasks and clinician expertise
27
ADHD and Autism
- no clear cause for ADHD or Autism
--> likely to be numerous contributing factors
- as there is no clear cause, there isn't a definitive test as with genetic conditions
- diagnosis is made by behavioural observations
--> match this to list of criteria in DMS-5
28
domains we test for in ADHD
- inattention
--> hyper focus
--> lack of attention
--> can have issues with maintaining attention
--> sustaining and disconnecting attention
- hyper activity and impulsivity
29
domains we assess for in Autism
1. deficits in social communication and social interaction
2. restricted, repetitive patterns of behaviour, interests or activities
30
what impairments do the ICD look for in autism
- impairments in social interaction
- impairments in communication
- repetitive behaviours within a narrow set of interests
31
what 3 main cognitive theories of autism have emerged?
1. theory of mind hypothesis
2. executive function hypothesis
3. central coherence hypothesis
