Aylin Küntay Language and Communicative Disorders Meeting 12 Mental Retardation Aylin Küntay Language and Communicative Disorders Meeting 12

3 features Lowered intelligence Impaired adaptive functioning (Vineland Adaptive Behavior Scale for Children) Onset during childhood Vs. Alzheimer disease Big variability (level of impairment) Mild MR (IQ: 55-70); 90%. Often not diagnosed during preschool years. Many go undiagnosed even at school. Easily confused w. learning disabilities. Moderate (IQ: 40-54); Down or Fragile X Severe (IQ: 20-39). Profound (IQ < 20).

Stability of IQ No correlation between infant IQs and IQ at 12 years of age Starts to become more predictive from school years on But more stable IQ for children with MR But might display unstability for individual children Correlations are for group data

Type of retardation DS: IQ might decrease over time Fragile X: steady IQ during preschool years; but declines around 10-15 years Some IQ instability, especially with mild MR

Developmental approaches Sequence: Universal sequence of development Similarly sequence sensorimotor development Cross-domain relations: do children with MR have the same organization of intelligence as do nonretarded children, when matched on MA? But DS demonstrates deficits in grammer relative to their abilities WS: high level linguistic abilites compared to MA Different strengths and weaknessed Need for definining various types of MR

Etiologies The 2-group approach Clear organic cause; should be differentiated Down syndrome Fragile-X syndrome Prader-Willi syndrome No clear organic cause (familial); slight hard-to-detect neurological problems; environmental deficits milder

Fragile-X syndrome Fragile site on x chromosome (causes underproduction of a protein); second leading etiology of MR Males shows more severe profiles; 15-20% show autism; more social anxiety hyperactivity

Prader-Willi syndrome Deletion on chromosome 15 Feeding/sucking problems during infancy; food preoccupations in 2 to 6 leading to obesity Obsesssive-compulsive symptoms

Fragile X videos http://www.youtube.com/watch?v=wGdH1M5lCVY http://uk.youtube.com/watch?v=nlZXu4-I6Fk (about 1 hour)

Progress report Describe very clearly (a) research/question background (b) what you aim (c) what you did so far *** (d) what is remaining 5-6 minutes for each group