atypical development Flashcards
define developmental psychology
the study of change and stability over lifespan
specifically: physically, cognitively, behaviourally, and socially
due to: biological, individual, and environmental differences
language used describing people
lots of language is negative (impairment, deficit) - use condition/difference instead
no “othering” - listen to those with lived experience - research led by those with condition
person first vs identity first language
person-first language e.g. person with autism
identity first language e.g. autistic person
reasons for atypical development (4)
pre-natal effects (e.g. exposure to teratogen)
- fetal alcohol spectrum disorder (FASD)
environmental effects (e.g. birth complications)
- cerebral palsy
genetic effects
- hereditary
- spontaneous mutations (copy number variants)
unknown (multifaceted)
- autism spectrum conditions
- ADHD
- intellectual disability
3 developmental conditions with known genetic causes
william’s syndrome
down’s syndrome
16p.11.2 (CNV)
genetics - 4 levels
DNA
genes (21,000 types)
chromosome
cell (23 pairs)
labelling parts of the chromosome
chromosome arm
- each has a short arm (p)
- and a long arm (q)
chromosome region
- small sections along the arm
- labelled with numbers
- lower numbers = closer to the centre
chromosomal abnormalities (2 ways)
too many or too few occurrences of particular genes
e.g. extra copy of chromosome 21 in Down’s syndrome
or parts of chromosomes (genes) that are either duplicated or deleted - CNVs = copy number variants
duplication = 16p11.2
deletion = William’s syndrome
16p11.2
CNVs related to ADHD, autism, intellectual disability, anxiety, OCD
deletion and duplication are both correlated
region on the short arm of chromosome 16
only detected when children are tested for developmental delay or autism
William’s syndrome
- cause
- symptoms
- incidence
spontaneous deletion at chromosome 7q11.2
distinct facial appearance, cardiac anomalies, highly sociable, atypical cognition (strong verbal IQ, weak performance/visuospatial IQ) connective tissue abnormalities
1/10,000 people
Down’s syndrome - cause
duplication of chromosome 21 - so have 3 copies of it rather than 2
can be full or partial copies with one of the arms
Down’s syndrome - physical characteristics (6)
- 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
Down’s syndrome - cognitive characteristics (5)
- Short attention span
- Impulsive behavior
- Slow learning
- Delayed language and speech development
- Variable IQ (average between 30 -70)
what is a teratogen
agent that causes change in an embryo
e.g. alcohol
FASD cause
fetal alcohol syndrome disorder
unclear how much alcohol needed to lead to FASD - depends on when during gestation it in consumed
binge drinking (4 drinks in 2 hours) leads to more severe symptoms
ethanol is thought to alter DNA and protein synthesis and inhibit cell migration - leads to physical and cognitive changes
estimated 2-3% children in Ontario have FASD
