The document defines intellectual disabilities as limitations in both intellectual functioning and adaptive behavior. It describes degrees of severity from mild to profound intellectual disabilities. Mild intellectual disability is characterized by IQ scores of 50-55 to 70, while profound intellectual disability involves IQ scores under 20-25. The document outlines clinical symptoms, common causes including Down syndrome, and goals of treatment which aim to develop independence and social skills.

1. Lecture 2: Intellectual Disabilities
Definition : Intellectual disability is disability characterized by
significant limitations in both intellectual functioning and in adaptive
behaviour, which covers many everyday social and practical skills.
Adaptive Behaviour- is the collection of conceptional, social, and
practical skills that are learned and performed by people in their
everyday lives.
 Conceptual skills-language and literacy; money, time, and
number concepts; and self-direction.
 Social skills—interpersonal skills, social responsibility, self-
esteem, gullibility, naïveté (i.e., wariness), social problem
solving, and the ability to follow rules/obey laws and to avoid
being victimized.
 Practical skills—activities of daily living (personal care),
occupational skills, healthcare, travel/transportation,
schedules/routines, safety, use of money, use of the telephone.
Degrees of Severity
MildMental Retardation
o IQ: 50-55 to approximately 70
Moderate Mental Retardation
o IQ: 35-40 to 50-55
Severe Mental Retardation
o IQ: 20-25 to 35-40
Profound Mental Retardation
o IQ: Less than 20-25

2. 1.)Mild Mental Retardation
 Previously referred to as “educable”
 Largest segment of those with MR (85%)
 Typically develop social/communication skills during
preschool years, minimal impairment in sensorimotor areas,
often indistinguishable from “typicals” until later age
 By late teens acquire skills up to approximately the 6th
grade
level
2.) Moderate Mental Retardation
 Previously referred to as “trainable”
 About 10% of those with MR
 Most acquire communication skills during early childhood
years
 Generally benefit from social/vocational training and with
moderate supervision can attend to personal care
 Difficulties recognizing social conventions which interferes
with peer relations in adolescence
 Unlikely to progress beyond the 2nd
grade academically
 Often adapt well to life in the community in supervised
settings (performing unskilled or semiskilled work)
3.)Severe Mental Retardation
 3 – 4% of those with MR
 Acquire little or no communicative speech in childhood; may
learn to talk by school age and be trained in elementary self-
care skills
 Can master sight reading “survival” words
 Able to perform simple tasks as adults in closely supervised
settings

3.  Most adapt well to life in the community, living in group
homes or with families
4.)Profound Mental Retardation
 1 – 2% of those with MR
 Most have an identifiable neurological condition that accounts
for their MR
 Considerable impairments in sensorimotor functioning
 Optimal development may occur in a highly structured
environment with constant aid
Etiology
Down’s Syndrome (most common genetic cause)
Fragile X Syndrome (accounts for 40% of all X-linked syndromes;
most common inherited cause)
Fetal Fetal alcohol Syndrome (most common attributable cause)
These 3 account for 30% of all identified cases of MR
Clinical Symptoms for All MR Patients
Speech
• Children with ID usually have delayed language development
and difficulties speaking and expressing themselves.
• The degree of severity varies with the level of impairment of
intellectual ability.
• Mild cases can achieve language skills that are only a little
poorer than children in the normal range of development.
• Severe or profound cases can’t communicate at all or speak
only a few words.

4. Perception
• Children with ID are slow in reacting and perceiving
environmental stimuli.
• They have difficulties distinguishing small differences in the
shape, size and color.
Cognition
• Capacity to analyze, reason, comprehend and calculate, and for
abstract thinking is often impaired to a greater or lesser extent
according to severity.
• Children with mild ID are capable of achieving reading and
mathematics skills to approximately the level of a typical child
aged 9 to 12
• Individuals with severe or profound ID lack the capacity to read,
calculate or even understand what others say.
Concentration and memory
• Ability to concentrate is low and narrow. By and large, memory
is poor and they are slow at remembering although there are
exceptions (e.g., savants).
• They have difficulties recalling and their memories are often
inaccurate.
Emotion
• Emotions are often naive and immature but may improve with
age.

5. • Capacity for self-control is poor and impulsive and aggressive
behavior is not uncommon. Some are timid, withdrawn and
shy.
Movement and behavior
• Children with ID often lack coordination, may be clumsy or
show excessive movement. Meaningless or stereotyped
movements (e.g., rocking, head-banging, teeth-biting, shouting,
tearing clothes, pulling hair, playing with the genitals) are
frequent in severe ID. Destructive, aggressive or violent
behavior can also be observed.
• Self-injurious behavior (e.g. self-slapping or biting) may occur in
moderate and severe ID.
Pathologies
1.) Downs Syndrome:
 Trisomy 21
 Signs and Symptoms
o Cranium- Flat Occiput
o Eyes- Inner Epicanthal Folds, Brushfield spots,
strabismus, Nystagmus
o Ears- over folded upper helix
o Facial- Protruding Tongue, Large cheeks, Flat nasal
fold, small nose.4
o Skeletal- short, excess nuchal skin, dysplastic hips,
vertebral anomalies
o Cardiac-Atrioventricular-Septal Defect
o CNS- Hypotonia,low IQ, Developmental Delay,
Hearing problems, Development of Alzheimers in
40s

6.  Relative strengths:
o Visual (vs. auditory processing)
o Social functioning
 Relative weaknesses:
o Language expression and pronunciation
2.)Fragile X syndrome
 Increases the risk for ADHD, autism (20-60%) & social
phobia
 Increasing deficits in adaptive and cognitive functioning
with age
 Relative strengths:
o Verbal long-term memory
 Relative weaknesses:
o Short term memory, VM integration, sequential
processing, math.
3.)Prader-Will Syndrome
 Deletion in chromosome 15
 H30- Hypotonia, hyperphagia, Obsessive Hyperphagia,
morbid Obesity
o Short stature, almond shaped eyes, small
hands/feet, mild to moderate MR,
Hypopigmentation.
 Relative stability in adaptive functioning during
adolescence and early adulthood
 Relative strengths:
o Expressive vocabulary, LT memory, visual/spatial
integration and visual memory (unusual interest in
jigsaw puzzles)
 Relative weaknesses:

7. o Temper tantrums, emotional lability, mood
symptoms , anxiety, skin picking, OCD symptoms
(>50% OCD)
4.)Angelman Syndrome
 Deletion In CHR 15
 Puppet Gait
 Severe MR, Ataxiam,
 Seizures
 Tremulousness
 Hypotonia midface hypoplasia
 Fair hair
 Uncontrollable laughter.
5.)Williams Syndrome
 Deletion of Elastin gene.#
 MR, supravalvular aortic stenosis, “elfin-like” facies,
infantile hypercalcemia, and growth deficiency
 Relative strengths:
o Remarkable facility for recognizing facial features
o Loquacious, pseudo-mature “cocktail party speech”
 Relative weaknesses:
o Increased risk for ADHD, Anxiety D/O
Assessment in General
– chromosomal
analysis
– Complete Blood
Count,
– echocardiography,
– yearly thyroid
test(t3/t4/tsh)
– atlanto-occipital x-
ray
– sleep study(EEG)

8. – hearing test – ophthalmology
assessment
– History & Physical Examination paints the picture ->
Tests confirm it
Treatment/Management
Goals
• The primary goal of treatment is to develop the person’s
potential to the fullest.
• Special education and training may begin as early as infancy.
This include social skills to help the person function as normal
as possible.
• There are specific programs that people with developmental
disabilities can take part in wherein they learn basic life skills.
• These "goals" may take a much longer amount of time for them
to accomplish, but the ultimate goal is independence.
• People with developmental disabilities learn throughout their
lives and can obtain many new skills even late in life with the
help of their families, caregivers, clinicians and the people who
coordinate the efforts of all of these people.
• Family psychoeducation
 explain problem to carers

9.  give parents skills to support child development
 promote participation in family, school and community
life
 address psychosocial needs of carers
• Advice for teachers
• Manage risk/contributing factors
 hearing and vision problems
 nutrition
 maternal depression
 lack of stimulation
• Manage co-occurring epilepsy, depression and behaviour
problems