Developmental Disorders

Chapter 13

Pervasive Developmental Disorders: An Overview

Nature of Pervasive Developmental Disorders Problems occur in language, socialization, and cognition Pervasive – Means the problems span the person’s

entire life

Examples of Pervasive Developmental Disorders Autistic disorder Asperger’s syndrome

Treatment of Autism and other PDD’s focuses upon: Acquisition of language skills Improving quality of social interactions Acquiring greatest possible functional skills

The Nature of Autistic Disorder: An Overview

Autism Significant impairment in social interactions and

communication Restricted patterns of behavior, interest, and

activities

Three Central DSM-IV and DSM-IV-TR Features of Autism Problems in socialization and social function Problems in communication – 50% never acquire

useful speech Restricted patterns of behavior, interests, and

activities

Autistic Disorder: Facts and Statistics

Prevalence and Features of Autism Rare condition – Affecting 2 to 20 persons for every

10,000 people; but prevalence is increasing considerably

Autism occurs worldwide Symptoms develop before 36 months of age

Autism and Intellectual Functioning 50% have IQs in the severe-to-profound range of

mental retardation 25% test in the mild-to-moderate IQ range (i.e., IQ of

50 to 70) Remaining people display abilities in the borderline-to-

average IQ range Better language skills and IQ test performance predict

better lifetime prognosis

Increasing Prevalence?

1966 epidemiological study (Lotter, 1966)

4-5/10,000 (.05%) 2002 review of recent studies

60 per 10,000 autism spectrum disorders (.6%) 8 to 30 per 10,000 for autistic disorder (.3%)

Probably reasons for increase Identification of children with higher and lower

intelligence Broadening and refining of criteria General awareness of the disorder Diagnosing disorder in children with other

difficulties

Asperger’s Disorder: Part of the Autistic Spectrum

The Nature of Asperger’s Disorder Such persons show significant social impairments Restricted and repetitive stereotyped behaviors May be clumsy, and are often quite verbal (i.e.,

pedantic or overly formal speech) Do not show severe delays in language and other

cognitive skills

Prevalence of Asperger’s Disorder Often under diagnosed Affects about 1 to 36 persons per 10,000 people

CAUSES OF AUTISM-SPECTRUM DISORDERS

Significant genetic component Families with 1 autistic child have 3-5% risk of

having a second child with autism (rate in general pop. Is .02-.05%)

Possible/probably neurological dysfunction High rate of MR, clumsiness, abnormal posture or

gait Abnormally small cerebellum

No evidence for psychosocial causes Poor parenting does not lead to autism or related

disorders (no “refrigerator mothers”)

TREATMENT

Specialized behavioral techniques using shaping, discrimination training, reinforcement to teach small steps

Communication – speech, sign language, use of picture board

Socialization – eye contact, some limited social behavior; does not usually result in “normal” relationships (e.g., friends)

Intensive, early intervention shows significant and in some cases, dramatic treatment 20-40 hrs/wk, beginning before age 6, 2+ years This is the most important and best treatment for the

disorder Support for family

Mental Retardation (MR): An Overview

Nature of Mental Retardation Below-average intellectual and adaptive functioning Range of impairment varies greatly across persons

Mental Retardation and the DSM-IV and DSM-IV-TR Significantly sub-average intellectual functioning (IQ

below 70) Concurrent deficits or impairments in two or more

areas of adaptive functioning MR must be evident before the person is 18 years of

age

DSM-IV and DSM-IV-TR Levels of Mental Retardation (MR)

Mild MR (85%) Includes persons with an IQ score between 50 or 55

and 70

Moderate MR (10%) Includes persons in the IQ range of 35-40 to 50-55

Severe MR (3-4%) Includes people with IQs ranging from 20-25 up to

35-40

Profound MR (1-2%) Includes people with IQ scores below 20-25

Other Classification Systems for Mental Retardation (MR)

American Association of Mental Retardation (AAMR) Defines MR based on levels of assistance required Examples of levels include intermittent, limited,

extensive, or pervasive assistance

Classification of MR in Educational Systems Educable mental retardation (i.e., IQ of 50 to

approximately 70-75) Trainable mental retardation (i.e., IQ of 30 to 50) Severe mental retardation (i.e., IQ below 30)

Implications of Different MR Classification Systems

Mental Retardation (MR): Some Facts and Statistics

Prevalence About 1% to 3% of the general population 90% of MR persons are labeled with mild mental

retardation

Gender Differences MR occurs more often in males, male-to-female ratio

of about 6:1

Course of MR Tends to be chronic, but prognosis varies greatly

from person to person

BIOLOGICAL CAUSES

Genetic (only about 30% cases of MR) Tuberous sclerosis (rare, but 60% have MR); PKU

(restricted diet till age 7 since unable to break down phenylalanine); Lesch-Nyhan syndrome

Chromosomal abnormalities Down Syndrome – trisomy 21 (extra 21st chromosome) Fragile X syndrome

PSYCHOLOGICAL & SOCIAL CAUSES

Cultural-familial retardation (70% cases of MR) – mild to moderate MR

combination of biological and psychological factors? abuse, neglect, social deprivation

TREATMENT OF MR

Goal of maximizing functioning Select reasonable goals for areas of functioning

Self-care (dressing, feeding self) Communication Social skills Tasks of daily living (transportation, buying groceries) Cognitive skills developed as appropriate (read, write,

make change) Use behavioral techniques to teach skills,

shaping, repeated trials, reinforcement Individuals with MR have higher rate of other

psychological disorders (depression, psychosis)