Intellectual disability
stefiat
Intellectualdisabilities.pptxOverview and Normality
Almost all psychological disorders are developmental disorders in the sense that they change over time
And most originate in child even if the symptoms don’t begin until adulthood
Neurodevelopmental disorders originate in childhood and persist overtime and the are all assumed to be neurologically based
Childhood is considered particularly important because of all the brain changes occurring in the first few years
Social, emotional, cognitive changes occur in sequence. Learn one and then another
So the disruption of any skills will impact the ability to learn other skills.
Example: The absence of early relationships has serious consequences
If people are not important to them what will motivate them to speak?
Knowing what processes are disrupted can help us understand the disorder better and develop interventions
Changes at biological and psychological level can reduce the impact of the disorder
Note of caution
There is great concern within the field that we are pathologizing normal development
For example, echolalia is not unique to autism. Many kids do this when first learning how to talk “mama mama mama mama” but w/ autism often we see it occurring later than it should. So this is a delay not a pathology
Book “the disease called childhood” or “Why French kids don’t have ADHD” two good examples of this perspective relative to ADHD.
Thoughts?
Intellectual Disability ID
Significantly below average intellectual and adaptive functioning
Difficulties with day to day activities
DSM V identifies difficulties in three domains
Conceptual (Language, reasoning, knowledge and memory)
Social (social judgment, ability to make friends)
Practical (managing personal care, getting a job)
History of treating people with ID is bad
Society has often devalued these ppl
The field has changed dramatically
ID is like ASD in terms of the variety of presentations
Some ppl can live independently and some can require help just to bathe or get dressed
Clinical description
Individuals can have mild to severe impairments
Language and communication skills are the most obvious impairments
Some may never learn to use speech
Cognitive processes are also affected so may have difficulty learning
Criteria in DSM V no longer includes several numeric cutoffs based on IQ
Instead looking at a comprehensive assessment of functioning
Must have below average intelligence though with an IQ of less than 70 but that is not sufficient for diagnosis
Also must have significant difficulty in areas such as communication, self-care, home living, social and interpersonal skills, use of community resources, self-direction, functional academic skills, work, leisure, health and safety
This is important because it does not include those who function well in society but do poorly on IQ tests
Below-average intellectual abilities must be present before age 18
That way can’t diagnose adults who suffer brain damage with ID
Clinical description continued…
This disorder perhaps more than any other is defined by society
The cutoff IQ score is based on statistics not on inherent qualities in the people who have ID
Little disagreement on diagnosing of those with severe disabilities but what about those in the mild range (which is the majority)
In the past the breakdown was according to IQ, approximately (give or take 5):
50-70 Mild- Should be able to live independently
35-50 moderate- same as above or w/ minimal help
20-40 severe- may not acquire speech and may need help with basics
Below 20 profound- same as above
Now DSM breaks it down into level of support needed: intermittent, limited, extensive, pervasive
Statistics
About 90% of people with ID have mild form so “intermittent support needed”
Total of 2% of population
Prognosis varies considerably, those with less severe forms can live normal productive lives
Chart above is prevalence of children receiving SES for ID in the US age 6-17
This is a chronic disorder
Over the last century IQ scores have risen meaning people have to constantly readjust IQ tests to keep the average around 100
What about those ppl who linger around the score of 70 and how do these adjustments affect them?
| Year | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 |
| Prevalence | 9.1 | 8.6 | 8.2 | 7.7 | 7.5 | 7.2 | 6.9 | 6.7 | 6.6 |
Causes
There are hundreds of known causes: environmental, prenatal, perinatal, postnatal
Heavy use of alcohol among pregnant women can lead to FAS, exposure to disease and chemicals during pregnancy, poor nutrition during pregnancy, lack of oxygen during birth, head injuries etc.
Genetic influences
Chromosomal disorders, single-gene disorders, mitochondrial disorders and multiple genetic mutations
Single gene disorders that involve a dominant, recessive or x-linked gene
Only a few dominant genes result in ID
Natural selection makes for those who carry ID on a dominant gene less likely to reproduce and pass the gene along
One example is tuberous sclerosis (1/30,000) leads to ID and seizures
PKU (phenylketonuria) on recessive gene. Leads to inability to break down phenylamine (found in diet soda for example)
Leads to ID, seizures, behavior issues
This can now be screened for but requires specialized diets that pregnant mothers may not stick to (or know about)
Lesch-nyhan syndrome is on the x chromosome found in males only, leads to ID and signs of cerebral palsy, SIB etc.
Most cases however have no known cause
Some studies have found genetic mutations in the sperm or egg occurring after fertilization in kids with ID of unknown origin
Causes continued
Chromosomal influences
Down syndrome or trisomy 21(extra 21st chromosome), is the most common chromosomal form of ID
Originally called mongoloidism due to facial features
Slanting eyes with folds in corners, flat nose, small mouth and protruding tongue
Also tend to have congenital heart problems and as adults are at higher risk for Alzheimer's
Risk is tied to maternal age; as age rises so does risk
Reason: eggs are exposed to all the toxins cumulative over the year or changes in hormones
But more kids with DS are born to young mothers simply because young mothers have more babies
Testing is available during pregnancy and positive tests lead to abortion 25% of the time
Fragile x
Mutation on the tip of the x chromosome, primarily affects males because they lack the other x
Women with the disorder have mild to moderate symptoms but me tend to have more severe symptoms
ID, short attention span, hyperactivity, perseverative speech
Psychosocial dimensions
Abuse, neglect and social deprivation can also contribute
Treatment
Biological treatment is not an option
Interventions typically resemble those for kids with ASD, teaching them independent living skills
Long term goals including participating in community life so the more severe the disability the more help they will need
Communication training, self care, vocational training etc.
Concerns expressed are often about people with ID being aggressive or SIB
Best way to address this has been debatable
Punishment is an option but there are alternative ways to address this w/o punishment including FCT
Current debate is where to do this teaching, in seclusion or in public schools with support?
Prevention
Early intervention can target and assist kids who are at risk for developing ID (based on impoverished environment)
National head-start program is a good program for early intervention
Combines education, medical and social supports for kids and their families
At some point we may be able to do prenatal gene therapy where we intervene on an identified genetically disordered fetus before birth
