Transcript IDEA-Definition of Serious Emotional Disturbance (SED)

Chapter 4
Mental Retardation
Definitions of Mental Retardation
• AAMR’s 1983 definition in IDEA
– Significantly subaverage intellectual functioning
– Deficits in adaptive behavior
– Manifested during the developmental period
• AAMR’s new definition based on needed supports
– Significant limitations in both intellectual functioning and
conceptual, social, and practical adaptive skills; the disability
originates before age 18
• Intensity of supports:
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Intermittent - As needed, short-term supports
Limited - Consistent support for limited time
Extensive - Consistent support in some settings
Pervasive - Consistent, high intensity support in most settings
Identification and Assessment
Assessing Intellectual Functioning
• Standardized tests are used to assess intelligence
– A diagnosis of MR requires an IQ score at least 2 standard
deviations below the mean (70 or less)
• Important considerations of IQ tests:
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IQ is a hypothetical construct
IQ tests measure how a child performs at one point in time
IQ tests can be culturally biased
IQ scores can change significantly
IQ testing is not an exact science
Results are not useful for targeting educational objectives
• Results should never be used as the sole basis for making
decisions regarding special education services
Normal Curve
Assessing Adaptive Behavior
• Adaptive behavior is the effectiveness or degree with
which the individual meets the standards of personal
independence and social responsibility expected of his
age and social group
– Measurement of adaptive behavior has proven difficult
because of the relative nature of social adjustment and
competence
– Adaptive Behavior Scales (ABS-S) – Observational scale. Part
1 – independent functioning Part 2-Maladaptive behavior
– Vineland – Informant assessment
– Scales of Independent Behavior-Provides a comprehensive
assessment of 14 areas of adaptive behavior and 8 areas of
problem behavior
Prevalence and Causes
Prevalence
• During the 2000-2001 school year, approximately 1% of the total
school enrollment received special education services in the MR
category
• Mild MR cases make up about 85% of all persons with MR
Causes
• More than 750 causes of MR have been identified
• For approximately 50% of mild MR cases and 30% of severe MR, the
cause is unknown
Biological Causes
• Prenatal causes include:
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Chromosomal disorders
Inborn errors of metabolism
Developmental disorders
Toxic exposure through maternal substance abuse
• Perinatal causes include:
– Intrauterine disorders
– Neonatal disorders
• Postnatal causes include:
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Head injuries
Infections
Degenerative disorders
Malnutrition
Chromosomal and Genetic Causes
• Tuberous sclerosis – Tumors in nervous system
• Phenylketonuria (PKU) – inability to metabolize enzyme
phenylalanine
• Hurler Syndrome – Inability to break down various
carbohydrates
• Tay-Sachs disease – abnormal buildup of lipids within body
tissue
• Fragile X – Triplet, repeat mutation on the X chromosome
• Down Syndrome -21st set of chromosome is a triplet
Environmental Causes
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Toxoplasmosis – Protozoic infection
Rubella – German measles infection
Radiation – Exposure to radiation in utero
Malnutrition – Pre- and post-natal lack of adequate nutrition
Drug abuse – exposure in utero
Blood type incompatibility
Mosquito bite - encephalitis
Anoxia – loss of oxygen (umbilical cord around neck)
Environmental Causes
• Biggest preventive strike was the development of the rubella
vaccine
Prevention
• The biggest single preventive strike against MR was the
development of the rubella vaccine in 1962
• Toxic exposure through maternal substance abuse and
environmental pollutants are two major causes of
preventable MR that can be combated with education and
training
• Advances in medical science have enabled doctors to
identify certain genetic influences
• Although early identification and intensive educational
services to high-risk infants show promise, there is still no
widely used technique to decrease the incidence of MR
caused by psychosocial disadvantage
Characteristics of Students with MR
• Mild MR
– Usually not identified until school age
– Most students master many academic skills
– Most able to learn job skills well enough to support themselves
independently or semi-independently
• Moderate MR
– Most show significant delays in development during the
preschool years
– As they grow older the discrepancies in age related adaptive
and intellectual skills widens
• Severe MR
– Usually identified at birth
– Most have significant central nervous system damage
– Likely to have health care problems that require intensive
supports
Wild Boy 1800
–Dr. Jean Marc Itard was the first to
develop a individualized educational
procedure. He developed a student
centered approach.
–Wild Child
– Itard, J.M.G. (1962). The wild boy of Aveyron. (G.
Humphrey & M. Humphrey, Trans.). New York:
Appleton-Century-Crofts. (Original works published
1801 and 1806).
Educational Approaches
Curriculum Goals
• Functional curriculum
– A functional curriculum will maximize a student’s
independence, self-direction, and enjoyment in school, home,
community, and work environments
• Life skills
– Skills that will help the student transition into adult life in the
community
• Self-determination
– Self-determined learners set goals, plan and implement a
course of action, evaluate their performance, and make
adjustments in what they are doing to reach their goals
Characteristics of Effective Instruction
• Explicit and systematic instruction
• Task analysis
• Direct and frequent measurement of student performance
• Active student response
• Systematic feedback provided by the teacher
• Transfer of stimulus control from prompts to task
• Generalization and maintenance
Educational Placement Alternatives
• Some children with MR attend special schools
• Most are educated in their neighborhood schools
– Special classes
– Regular class with support
– Resource room
• The extent to which a student with MR should be included
in the regular classroom should be determined by the
student’s individual needs
Current Issues and Future Trends
• Some concerns of the current definition of MR include:
– IQ testing will remain the primary means of assessment
– Adaptive skills cannot be reliably measured with current
assessment methods
– The levels of need supports are too subjective
– Classification will remain essentially unchanged in practice
• Acceptance and membership
– An especially important and continuing challenge is moving
beyond the physical integration of persons with MR in society
to acceptance and membership that comes from holding
valued roles