Intellectual Disability Flashcards
(24 cards)
How is psychology concerned with intellectual disability?
-definition, diagnosis & classification,
-Incidence and prevenance
-Psychometric assessment
How does the DSM-5 define intellectual disability?
What are it’s diagnostic criteria’s?
Neurodevelopmental disorders or intellectual developmental disorders
1)evidence from childhood
2)deficits in general mental abilities confirmed by assessment
3)limitations in adaptive functioning
DSM has specifiers to demonstrate severity (mild, moderate, severe, profound). These are split across the social, cognitive and practical domains
What are examples of mild intellectual disability?
-Conceptual difficulty learning to read and write
-Socially immature
-Practically require support with transport, shopping and finance.
What are the characteristics of intellectual disability?
-Evidence from childhood (before 18)
-If someone previously functioned normally, then becomes mentally deficit, this is due to something else
-Significantly low IQ - two SD below mean (70). About 3% of the population
-Classification shouldn’t be based on IQ alone! Adaptive functioning more important
-Consideration of cultural concept
What is meant by adaptive functioning?
Conceptual, social and practical adaptive skills
Can be viewed as the fit between cultural expectations and behavioural performance
What is the history of the classification of intellectual disability?
Esquirol (18002), idiots and imbeciles - idiots more severe
Guggenbuhl, cretinism (1800s), deficits from iodine deficiency.
Changing terminology, crippled children’s society to CCS disability action in 2017
What are the different ways of classifying intellectual disability?
-Aetiology or cause
-Mental ability
-Educational classification
-Support needs
How is down syndrome classified by aetiology?
Genetic
-Down syndrome (non-disjunction of chromosome 21 during meiosis)
-1 in every 735 live births
-typically mild-moderate intellectual disability
-IQ 40-70 range
-Executive functioning may be impaired
-Social behaviour a strength
-Vulnerable to Alzheimer’s.
How is fragile X syndrome classified by aetiology?
-Fragile X is classified by mild emotional or learning problems to severe intellectual disabilities with autism - intellectual individuals with full mutation alleles usually function in the mild to moderate intellectual disability range
verbal skills stronger than visuospatial and mathematical
-Cause my mutation on gene FMR1
-1 in every 3600
How is intellectual disability classified by support needs?
Intermittent, limited, extensive, pervasive.
How is intellectual disability classified by intellectual ability?
Wechsler scales >70.
Grossman (1983)
mild 50-70
moderate 30-50
severe 20-30
profound >20
“you can’t really measure IQ below 50”
Define incidence and prevalence in epidemiology
Incidence:
the number of new cases occurs in a certain time period, in a year
Prevalence:
The total number of people with a disease of condition in a population at a point in time
Prevalence of people with Intellectual disability
-CIDS (cog, int, dis) around 1% of population
- 1% in most countries
-Severe is around 6 per 100,000
How is intellectual disability measured through adaptive behaviour?
-Evidence since childhood
-Low intellectual ability
-Adaptive functioning deficits
What are the vineland adaptive behaviour scales
Evaluates people with intellectual and developmental disabilities
Measures daily living skills - what you can/can’t do without assistance
Can be used on a range of things
What are the ABAS-3?
A rating scale for measuring adaptive behaviour
How well/often we do things.
Measures 10 specific skills/domains:
-Communication
-Community
-Functional academics
-Home living
-Health and safety
-Leisure
-Self-care
-Self-direction
-Social
-Work
How is the ABAS-3 measured and developed?
10 domains,
25 questions per domain
4 point Likert scale
250Q total
New items written for ASD, ADHD and ID.
ABAS-3 has been standardised. All skills given a mean and SD for standardisation purposes.
What is the reliability of the ABAS-3?
Test-retest:
Reported for all age groups and adaptive skills
test-retest was done over 3 weeks
R=0.78 communication skills
Inter-rater reliability:
Reported for all age groups and adaptive skills
r=0.8 functional academics
What is the validity of the ABAS-3
Concurrent and convergent validity
-correlation with vineland, Reynolds, and other IQ tests
Clinical or criterion groups
-children with ASD and ID
How is intellectual disability assessed through receptive vocabulary?
Peabody picture vocabulary test PPTV-5
“point to the chicken”
Used for people with speech impairment
Two-parallel versions
Has been standardized to be representative of US population aged 2 - 90.
What is the reliability and validity of the PPTV-5?
Reliability proven through internal consistency and split-half, test-retest, parallel forms
Validity:
-content validity
-concurrent/convergent
-criterion groups
How is intellectual disability measured through behavioural assessment?
Behaviour modification and Applied Behaviour Analysis
-Operant psychology - Skinner
-Operationalization of behaviour
-Behaviour modified by it’s consequences
-ABCs of behaviour
-Stimulus control
Very relevant to ID
Define stimulus control and generalisation?
Stimulus control:
Environmental stimuli that reliably predict positive or negative consequences will influence behaviour
Generalisation:
-Stimuli similar to learned one will influence behaviour
What is the token reinforcement case study?
Obesity and walking, token reinforcement, ABAB design
