Autism and Other Pervasive Developmental Disorders

Pervasive Developmental Disorders (PDDs)

Serious conditions characterized by “severe and pervasive impairment” in at least one of three areas of functioning:

(1) reciprocal social interaction,

(2) communication, or

(3) the presence of stereotyped behaviors, interests, or activities

Autistic Disorder Asperger’s Disorder

A persistent and pervasive A persistent and pervasive

deficit in three general areas: deficit in two general areas:

(1) social interaction, (1) social interaction, and

(2) communication, and

(3) flexible, adaptive behavior (2) preoccupation with idiosyncratic topics

Note: No marked delays in language

No marked deficits in intellectual or adaptive functioning

Language Characteristics of Children with Asperger’s Disorder

Language and communication Percentage

Not aware of social situation when talking 68%Talks in monologues, comments on own actions, or talks to self 56%Shows deviant modulation (e.g., monotonous) or articulation (e.g., over-exact) 54%Gets off-topic or derailed when talking 33%Pedantic or long-winded speech 30%Verbosity or “endless talking” 28%Obsessive questioning, frequently debates with others, argumentative 26%Precocious, “know-it-all” 21%Neologisms (i.e., makes up or uses unusual words or phrases) 21%Common speech problems (e.g., stutters, lisps) 21%Echolalia (i.e., repeating words of phrases) 19%

Speech characteristics of 43 children and adolescents initially seen by Hans Asperger and colleagues. Based on Hippler and Klicpera (2003).

Pervasive Developmental Disorders-Not Otherwise Specified (PDD-NOS)

Used when children display severe and pervasive impairment in social interactions, communication skills, or stereotyped interests and behaviors, but do not meet full diagnostic criteria for any other pervasive developmental disorder

Examples:

Childhood-onset autismResidual autismChildren with features of autism, but not enough to meet diagnostic criteria

Autism Spectrum:

• Autistic Disorder• Asperger’s Disorder• PDD-NOS

Associated Features

Mental Retardation

Anxiety & Depression

ADHD

Tics & Tourette’s Disorder

Tics: sudden, rapid, and recurrent motor movements or vocalizations that that are beyond the individual’s control

Tourette’s Disorder:a psychological condition characterized by the presence of multiple motor tics and at least one vocal tic

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Autism Asperger Rett's CDD PDD-NOS

Pervasive Developmental Disorder

Prevalence of pervasive developmental disorders in the general population. Most data indicate that autism spectrum disorders affect 3.6 per 1000 youth. However, recent data indicate that the prevalence of autism spectrum disorders may be as high as 6.6 per 1000 youth. Based on Centers for Disease Control (2007) and Fombonne (2005).

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Adult Outcome

Adult outcomes of people with autism. Most individuals with autism have problems in social functioning throughout life. Based on Howlin (2005).

Etiology

Genetics:

MZ concordance 31%-91%

DZ concordance 5% or less

The Autism Genome Project has identified 19 different genes that likely play roles in the development of autism spectrum disorders

Etiology

Biological causes:

• Enlarged brain volume

• Atypical brain density

• Hypoactivity of amygdala

• Hypoactivity of right fusiform gyrus

• Deficits in executive functioning (esp. orbital & medial prefrontal cortex)

Baron-Cohen (2005) suggests that children with autism spectrum disorders show “social brain” deficits

Etiology

Deficits in social cognition:

Children later diagnosed with autism show early social deficits

• Problems with joint attention might affect social and language development.

• Problems with social orientation might affect children’s understanding of

social situations and processing others’ emotions

• Delays in symbolic (pretend) play might underlie children’s problems

understanding others and responding empathically

Problems with social orientation. Researchers tracked the gaze of individuals without autism (black) and people with autism (white) as they watched films of social interactions. People without autism attended to actors’ eyes and the objects of joint attention. People with autism attended primarily to inanimate objects in the room and often missed important aspects of the

social interaction.

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No diagnosis Down syndrome Autism

Child's Diagnosis

Children with autism often fail the false-belief task, but healthy children and children with Down syndrome usually pass this task. These results indicate that children with autism have problems with theory of mind, that is, understanding the

intentions and motives of others. Based on Baron-Cohen and colleagues (1985).

A developmental model for autism. In this general model, individuals show genetic risk for the disorder which can lead to structural and/or functional differences in the developing brain. Brain abnormalities, in turn, can lead to problems in the development of social cognition during infancy. Social cognitive abnormalities also affect developing brain structure. By early childhood, deficits are severe enough to merit the diagnosis of autism.

Treatment: Early Intensive Behavioral Intervention (EIBI)

• Focuses on children’s overt behavior

• Practitioners use learning theory to guide treatment

• Therapists structure the environment to maximize learning

• The main technique is discrete trial training

A behavior is selected by the therapist

The behavior is broken down into component parts

Each part is introduced, modeled, and practiced

Therapist liberally reinforces successful execution of behavior

Therapist initially provide prompts; later, prompts are faded

Later skills build upon early skills

Treatment: Pivotal response Training

• A home-based behavioral intervention designed to increase the motivation and self-regulation skills of children with autism

• Learning is directed by the child and occurs in naturalistic settings

• Parents act as primary therapists for their children

• Child is taught to ask questions to increase his/her motivation to learn

• Therapy specifically targets children’s self-management skills

• Parents reinforce children for attempts at executing behaviors, not only on successful behavioral completion

Treatment: Treatment and Education of Autistic and related Communication-handicapped Children (TEACCH)

• A classroom-based intervention program that relies heavily on observational learning, prompts, and operant conditioning to improve children’s behavioral and communicative skills

• The primary technique is structured teaching; tasks are broken down and scaffolded by teachers/therapists so that children can successfully complete them

• Therapy techniques used in the classroom are also taught to parents; one therapist works with the child and one therapist serves as a parent consultant

Treatment: Academic Inclusion

• Children with autism spectrum disorders are entitled to a free appropriate public education and academic accommodations according to IDEA (2004)

• Academic inclusion is based on the notion that children with developmental disabilities can benefit from interactions with other typically developing children

• For academic inclusion to be beneficial, typically-developing classmates need to be systematically taught how to interact with a classmate with autism

• The main criticism of academic inclusions is that it is technically not a treatment approach; it simply refers to the setting in which treatment takes place

Treatment: Interventions with limited empirical support

Why might parents select a treatment with limited empirical support?

1. Many parents are not aware of the empirical data regarding the treatment for autism. Consequently, most parents might rely on advice from therapists, paraprofessionals, or well-meaning friends—advice that might not be empirically based.

2. Many parents have tried one of the more traditional approaches to treatment and have meet with limited success.

3. High-quality and empirically supported treatments for autism are unavailable to many families