Transcript 4-5 Definitions of Intellectual Disability

Exceptional Children
An Introduction to Special Education
Tenth Edition
William L. Heward
© 2013, 2009, 2006, 2003, 2000
Pearson Education, Inc. All rights reserved.
Chapter 4
Intellectual Disabilities
Focus Questions
What
implications for special education does viewing
intellectual disabilities as an inherent trait within the individual
or as a state of functioning that reflects the fit between a
person’s capacities and the contexts in which the person is to
function?
What
should teachers know about IQ tests and the
assessment of intellectual functioning?
Which
is more important in determining a person’s level of
adaptive functioning: intellectual capability or a supportive
environment?
How
are the characteristics of students with intellectual
disabilities relevant to planning and delivering instruction?
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Focus Questions (cont.)
What
factors might account for the wide differences in the
prevalence of intellectual disabilities within the school-age
population across states and school districts?
Why
has the prevention of intellectual disabilities proven so
difficult?
What
should curriculum goals for students with intellectual
disabilities emphasize?
What
are the most important features of effective instruction
for students with intellectual disabilities?
What
is needed to make education for a student with
intellectual disabilities appropriate in a general education
classroom?
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Definitions of Intellectual
Disability (ID)
IDEA Definition
•
Significantly sub-average intellectual functioning
•
Deficits in adaptive behavior
•
Manifested during the developmental period
Three criteria for a diagnosis
•
Significant sub-average intellectual functioning - a score of
two or more standard deviations below the mean on
standardized intelligence tests
•
An individual must also have significant difficulty with
adaptive behavior
•
The deficits in intellectual functioning and adaptive behavior
must occur during the developmental period to help
distinguish intellectual disabilities from other disabilities
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Definitions of Intellectual Disability
(cont.)
AAIDD 2002 definition
•
Intellectual disability is characterized by significant limitations
in both intellectual functioning and in adaptive behavior as
expressed in conceptual, social, and practical adaptive skills.
This disability originates before age 18.
Five assumptions essential to applying the definition
•
Limitations in present functioning must be considered within
the context of community environments typical of the
individual’s age peers and culture.
•
Valid assessment considers cultural and linguistic diversity as
well as differences in communication, sensory, motor, and
behavioral factors.
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Definitions of Intellectual Disability
(cont.)
Five assumptions essential to applying the AAIDD definition
(cont.)
•
Within the individual, limitations often coexist with strengths.
•
The purpose of describing limitations is to develop a profile of
needed supports.
•
With appropriate personalized supports over a sustained
period, the life functioning of the person with intellectual
disability generally will improve.
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Classification of Intellectual Disabilities
by IQ Score
Classification by the degree or level of intellectual
impairment as measured by IQ test
Mild
50-55 to approximately 70
Moderate
35-40 to 50-55
Severe
20-25 to 35-40
Profound
Below 20-25
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Identification and Assessment
Assessing Intellectual Functioning
Standardized IQ tests are used to assess intelligence
Important considerations of IQ tests:
•
IQ is a hypothetical construct
•
IQ tests measures only how a child performs at one point in
time on the items included on the test
•
IQ tests can be culturally biased
•
IQ scores can change significantly
•
IQ testing is not an exact science
•
An IQ score should not be used to determine IEP objectives
•
An IQ score should never be used as the sole basis for
making decisions regarding special education services
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Assessing Adaptive Behavior
•
Adaptive behavior is the collection of conceptual, social, and
practical skills that have been learned by people in order to
function in their everyday lives.
•
The adaptive skills exhibited by a person with ID are critical
factors in determining the supports a student requires for
success in school, work, community, and home
environments.
•
Measurement of adaptive behavior has proven difficult
because of the relative nature of social adjustment and
competence.
• Most instruments consist of a series of questions that a
person familiar with the individual answers,
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Characteristics of Students with ID
Cognitive functioning
•
•
•
•
•
Memory
o Difficulty remembering information
Learning rate
o Well below that of typically developing children
Attention
o Slower to attend to relevant features of a learning task
than students without disabilities
Generalization and Maintenance
o Trouble using new knowledge and skills in settings
different from the context in which they first learned those
skills
Motivation
o Exhibit an apparent lack of interest in learning or in
problem-solving tasks
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Characteristics of Students with ID
Adaptive behavior
•
•
•
Self-care and daily living skills
o Individuals who require extensive supports must be taught
basic self-care skills
Social development
o Maintaining and sustaining friendships and personal
relationships present significant challenges for many with ID
Behavioral excesses and challenging behavior
o More likely to exhibit behavior problems than are children
without disabilities
Positive Attributes
•
•
•
Many display tenacity and curiosity in learning
Get along well with others
Are positive influences on others
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Prevalence and Causes
•During
the 2009–2010 school year, 460, 964 students ages 6 through
21 received special education under the category of ID.
•
These students represented 7.8% of all school-age children in special
education.
•ID
is the fourth-largest disability category.
•Prevalence
rates vary greatly from state to state.
Causes
•
•
•
•
More than 350 risk factors associated with ID have been identified.
35% of cases have a genetic cause
Another third of cases involve external trauma or toxin
Etiology remains unknown for another third of cases
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Biological Causes
Prenatal causes include:
•
Syndromes
•
Chromosomal disorders
•
Maternal illnesses/Parental age
Perinatal causes include:
•
Prematurity
•
Birth injury
•
Neonatal disorders
Postnatal causes include:
•
Head injuries
•
Infections
•
Degenerative disorders
•
Malnutrition
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Environmental Causes
Psychosocial disadvantage occurs when no biological
risk factor is evident as a cause of ID.
Environmental influences include
• Poverty and malnutrition
• Minimal opportunities to develop early language
• Child abuse and neglect
• Chronic social or sensory deprivation
• Lack of access to prenatal or birth care
• Parental drug use or smoking
• Parental immaturity or cognitive disability
• Parental lack of preparation for parenting
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Prevention
The
biggest single preventive strike against ID was the
development of the rubella vaccine in 1962
Toxic
exposure through maternal substance abuse and
environmental pollutants are two major causes of preventable
ID that can be combated with education and training
Advances
in medical science have enabled doctors to identify
certain genetic influences using the following screening
procedures and diagnostic tests
o Ultrasound and maternal serum alpha-fetoprotein
o Amniocentesis
o Chronic villi sampling
o Genetic counseling
o Mandatory newborn screening tests for inherited and
biomedical risk factors
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Educational Approaches
Curriculum Goals
Academic curriculum
• Content in the basics of reading, writing, and
math
Functional curriculum
• Content to increase a student’s independence,
self-direction, and enjoyment in school, home,
community, and work environments
Self-determination
• Content to help a student set goals, plan and
implement a course of action, evaluate their
performance, and make adjustments in what they
are doing to reach their goals
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Instructional Methods
Task Analysis
• Breaking down complex or multisteps into smaller subtasks
Active Student Response
• An observable response made to an instructional antecedent
Systematic Feedback Provided by the Teacher
• Information provided to students about their performance
Transfer of Stimulus Control
• Gradually and systematically withdrawing response prompts
Generalization and Maintenance
• The use of what is learned across settings and over time
Direct and Frequent Measurement of Student Performance
• Objective and frequent recording the performance of
behavior
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Educational Placement Alternatives
During the 2008–2009 school year, 17% of students
with ID were educated in the general education
classroom
27% were served in resource room programs
48% were served in separate classes
7% of students with intellectual disabilities are
educated in separate schools, residential facilities,
or home/hospital environments
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