7/8/2013 ABNORMAL PSYCHOLOGY SEVENTH EDITION CHAPTER FIFTEEN CHAPTER OUTLINE. Intellectual Disabilities and Autistic Spectrum Disorders

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1 ABNORMAL PSYCHOLOGY SEVENTH EDITION Oltmanns and Emery PowerPoint Presentations Prepared by: Ashlea R. Smith, Ph.D. This multimedia and its contents are protected under copyright law. The following are prohibited by law: any public performance or displays, including transmission of any image over a network, preparation of any derivative work, including the extraction, in whole or in part, of any images, any rental, lease, or lending of the program. CHAPTER FIFTEEN Intellectual Disabilities and Autistic Spectrum Disorders CHAPTER OUTLINE Intellectual Disabilities Autistic Spectrum Disorders 1

2 OVERVIEW Autism is the most familiar ASD, which is why professionals increasingly use the term autistic spectrum disorders. Autistic spectrum disorders are distinguished by dramatic, severe, and unusual symptoms. Contrary to some views, most people with ASD also have intellectual disabilities. Three major criteria: Significant subaverage IQ (e.g., test s rating of intellectual abilities): IQ of approximately 70 or below, as measured by an IQ assessment Wechsler Intelligence Scale for Children, Fourth Edition (WISC-IV), and the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) Deficits in adaptive behavior Onset before age 18 years FIGURE 15 1 Contemporary IQ tests have a mean of 100 and a standard deviation of 15. The IQ cutoff for mental retardation (70) is two standard deviations below the mean. 2

3 Controversies About Intelligence Tests Culture-fair tests (cultural bias) How well intelligence is measured among people with intellectual disabilities What is intelligence? Limitations in adaptive skills Adaptive skills are judged by age Deficits in adaptive skills are less stable than IQ Diagnosis of Intellectual Disabilities Early Diagnostic Efforts The creation of IQ tests helped to improve the classification of intellectual disabilities. There has always been some controversy about the IQ cutoff score. Cutoff changed to 1 SD in1959 then back to 2 SD in Diagnosis of Intellectual Disabilities Contemporary Diagnosis DSM-IV-TR divides Intellectual disabilities into four levels based on IQ scores: Mild to 70 Moderate to Severe to Profound Below

4 Frequency of Intellectual Disabilities Theoretically, IQ is distributed according to the normal curve, so 2.3% of the population should have IQs of 70 or below. In reality, however, more than 2.3% of people have IQ scores below 70. Very low IQ scores, in particular, are found more often than expected, a result of the various biological conditions that produce mental retardation (Volkmar & Dykens, 2002). Causes of Intellectual Disabilities Chromosomal Disorders The most common known biological cause of MR is the chromosomal disorder is Down Syndrome. Children with Down Syndrome have 47 chromosomes rather than the normal 46. Fragile-X syndrome Most common genetic cause of MR Genetic Disorders PKU What is the twocurve model of intellectual disabilities? FIGURE 15 2 The Two-Curve Model of Intellectual Disabilities 4

5 Causes of Intellectual Disabilities Infectious Diseases Cytomegalovirus Toxoplasmosis Rubella HIV Syphilis Genital herpes Encephalitis Meningitis Causes of Intellectual Disabilities Toxins Alcohol: fetal alcohol syndrome (FAS) Mercury poisoning Lead poisoning Other Biological Abnormalities Rh incompatibility Premature birth Normal Genetic Variation Cases of intellectual disabilities of unknown etiology often referred to as cultural-familial retardation are generally assumed to be variations in the normal distribution IQ. Estimates generally indicate that up to 75% of the normal range of intelligence is attributable to genetics, but no research specifically identifies the extent of genetic contributions to cultural-familial retardation (Thapar et al., 1994). 5

6 Normal Genetic Variation Psychological Factors Grossly abnormal environments can produce gross abnormalities in intelligence. Social Factors Cultural-familial retardation is found far more frequently among the poor. Impoverished environments lack the stimulation and responsiveness required to promote children s intellectual and social skills throughout their development. Treatment: Prevention and Normalization Primary Prevention Availability and use of good maternal and child health care Planning for pregnancy Amniocentesis Gene therapy (future) Ultrasound Secondary Prevention Head Start Programs Treatment: Prevention and Normalization Tertiary Prevention Careful assessment early in life is critical to tertiary prevention. Medical screening is essential for detecting conditions like PKU. Treatment of the social and emotional needs of people with intellectual disabilities may include teaching basic self-care skills, such as feeding, toileting, and dressing, during the younger ages and various life-survival skills at later ages. 6

7 Treatment: Prevention and Normalization Normalization Normalization means that people with intellectual disabilities are entitled to live as much as possible like other members of society. The major goals of normalization include mainstreaming children with intellectual disabilities into public schools and promoting a role in the community for adults with intellectual disabilities. AUTISTIC SPECTRUM DISORDERS Autistic spectrum disorders (ASDs) begin early in life and involve impairments in relationships, communication, and behaviors. Autism is the best known and researched ASD. Autism is characterized by profound indifference to social relationships; odd, stereotypical behaviors; and severely impaired or nonexistent communication SYMPTOMS OF ASD EARLY ONSET Normal physical appearance is one reason why autism, which begins early in life, may go unrecognized In 20% to 40% of cases, children develop normally for a time but either stop learning new skills or lose the skills they have acquired (Volkmar, Chawarska, & Klin, 2005) IMPAIRED COMMUNICATION Communication problems in ASD range from few difficulties in Asperger s disorder to profound impairments in many cases of autism Dysprosody Echolalia Failure to individuate 7

8 FIGURE 15 5 Where will Sally (on left) look for the marble? Many children with autism answer in the box, evidence that they may lack a theory of mind. AUTISTIC SPECTRUM DISORDERS STEREOTYPED BEHAVIOR, INTERESTS The third defining symptoms of autism is restricted, repetitive, and stereotyped patterns of behavior, interests, and activities APPARENT SENSORY DEFICITS Respond to auditory, tactile, or visual sensation in a highly unusual and idiosyncratic manner Apparent sensory deficits Higher level of perception problems AUTISTIC SPECTRUM DISORDERS SELF-INJURY One of the most bizarre and dangerous difficulties of autism Examples: repeated head banging, and biting the fingers and wrists Should not be misinterpreted as suicidal behavior SAVANT PERFORMANCE An exceptional ability in a highly specialized area of functioning Typically involves artistic, music, or mathematical skills No adequate theory for savant performance 8

9 AUTISTIC SPECTRUM DISORDERS Diagnosis of Autism and ASD Contemporary Classification The new diagnosis for Asperger s is identical to autism, except it involves no clinically significant delay in language Retts Disorder Childhood disintegrative disorder Very rare condition characterized by severe problems in social interaction and communication, in addition to stereotyped behavior FIGURE 15 6 Autistic Spectrum Disorders in Selected Sources CAUSES OF AUTISM PSYCHOLOGICAL AND SOCIAL FACTORS For many years, parents were blamed for causing autism in their children Such harmful assertions are simply wrong Mounting evidence on biological causes GENETICS In the largest study to date, concordance rates were 60% for MZ twins and 0% for DZ twins For a broader spectrum of disturbances, the rates were 92% for MZ and 10% for DZ twins in the same study Endorphins and neuropeptides 9

10 TREATMENT OF AUTISM Controversy exists and everyone acknowledges there is no cure for autism A recent review concluded that 20% achieve a good outcome Language skills predicts positive prognosis Medication Antipsychotics (Risperdone) SSRIs No medication is effective treatment FIGURE 15 7 Adult outcomes for children diagnosed with autism. Outcomes are somewhat better in more recent studies, but good outcomes are infrequent and poor outcomes remain most common. One major change is that, in recent studies, far fewer adults with autism were cared for in institutions, reflecting increased family and community care. AUTISM AND THE PERVASIVE DEVELOPMENTAL DISORDERS APPLIED BEHAVIOR ANALYSIS Intensive behavior modification using operant conditioning techniques ABA therapists focus on treating the specific symptoms of autism, including communication deficits, lack of self-care skills, and selfstimulatory or self-destructive behavior APPLIED BEHAVIOR ANALYSIS If the first goal of ABA is to identify very specific target behaviors, the second is to gain control over these behaviors through the use of reinforcement and punishment 10