10: Neurodevelopmental Disorders Flashcards
What is intellectual disability?
IQ of less than 70
Impairment in intellectual functioning and everyday activities
Large variation
How do cognitive tests have to be adapted for people with intellectual disabilities?
Easy read documents Model responses Fewer items Simple task instructions More time on responses
What is the floor effect?
Where the least difficult items on a test are still too difficult for some people
What comparison populations can we use when studying intellectual disability?
Chronological age: People of the same age
Mental age: Those of the same mental abilities
What is a chronological age matched control group?
A control group of typically developing people of the same age
What is a mental age matched group?
Typically developing people with the same cognitive abilities
Not always the same age
What causes down syndrome?
Trisomy of chromasome 21
What is the prevelance of down syndrome?
6.6 people per 10,000
What did Pennington find about people with down syndrome?
They have impaired memory
What did Lanfranchi find about peopel with down syndrome?
They have a general impairment of executive functioning capabilities
How do the cognitive abilities of those with down syndrome compare with the normal population?
Poor expression of langiage
Impaired verbal memory
Difficulties in executive functioning
How is the brain of peope with down syndrome different?
Smaller frontal lobe and hippocampus
Ventral visual stream is affected which leads to poor object memory
Later developing areas are more affected
What is the link between dementia and down syndrome?
Higher risk with an earlier onset
What percentage of people with down syndrome go on to develop dementia?
95%
What causes Williams syndrome?
Deletion of 27 genes from a copy of chromosome 7
