News and Notes about Scientific Research on Autism and other Developmental and Behavioral Disorders

Editor: Bill Ahearn, Ph.D., BCBA
Director of Research, New England Center for Children

New Studies on the Prevalence of ASDs

The Centers for Disease Control (CDC) has recently released the first national surveys of autism prevalence in the United States. Prevalence refers to the number of affected persons. Two studies, the National Health Interview Survey and the National Survey of Children's Health were conducted to estimate how often autism and specific child development and health concerns occur. The studies cover 2003 through 2004 and found that parents reported that autism was diagnosed for between 5.5 and 5.7 per 1,000 (1 in 175-181) children between the ages of 4 and 17 years old. This indicates that approximately 300,000 children in the US from 2003-2004 carried a diagnosis of an autism spectrum disorder (ASD). These estimates are slightly lower than the 1998 study of autism prevalence in Brick Township NJ (1 in 166) and higher than the 1996 surveillance estimate obtained for Metropolitan Atlanta (1 in 296). However, the confidence intervals (which refer to how far off the true prevalence may be from the estimated prevalence) in the new CDC surveys suggest that the occurrence of autism could be as high as 1 in 139 children. It was also noted that peak of prevalence occurred in children between 6 and 11 years old. This could mean that autism is more often diagnosed after the child enters school and ASDs might occur more frequently than estimated.

Though these studies are very important for determining how many persons have autism, they do not begin to address the question of whether the prevalence of ASDs is increasing. As implied by the CDC data and suggested by some autism experts (e.g., Wing & Potter, 2002), the true prevalence of autism may be higher than the current best estimates. Some have suggested that ASDs are decreasing in prevalence while others have suggested that the increased rates of autism are due to inaccurate diagnoses. In the highly regarded medical journal Pediatrics, Shattuck (2006) reviewed state educational databases for special needs children and found direct correlation between the increase in the diagnosis of an ASD and a decrease in the diagnosis of mental retardation. One problem with coming to sound conclusions based on such evidence is that currently there are inadequate systems in place for determining the prevalence of autism through school records. Estimates of prevalence based on educational databases or passive reporting systems are inadequate in that case finding is unsystematic and both are subject to intentional or unintentional biases.

The CDC publication may be found at:

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5517a3.htm
Shattuck, P. (2006). The contribution of diagnostic substitution to the growing administrative prevalence of autism in US special education. Pediatrics, 117(4), 1028-37. Wing, L. & Potter, D. (2002). The epidemiology of autistic spectrum disorders: Is the prevalence rising? Mental Retardation and Developmental Disabilities Research Reviews, 8(3), 151-161.

Time Magazine Promotes Facilitated Communication

In Time's magazines recent coverage of autism ("Inside the Autistic Mind" and "A Tale of Two Schools" by Claudia Wallis) some important advances in our understanding of this spectrum of disorders, such as its high prevalence and its complex etiology, are discussed. In fact, the author should be commended for including Isaac Pessah's expert opinion that thimerosal, previously used as a preservative in vaccines since the 1930s and widely discussed as triggering an autism epidemic, is not likely the cause of autism. However, she should be taken to task for touting Facilitated Communication (FC) as an effective intervention. More than 40 scientific studies have shown that FC is ineffective. The best studies have used double-blinded experimentation showing that those "facilitating" the person with communicative responding are controlling what is said. Another treatment described in the article was Floortime. There have been no rigorous, controlled studies demonstrating that Floortime is effective and there are good reasons to question the underlying theories of those procedures. Greenspan is a psychoanalyst and this psychological perspective is the one that suggested that parents were responsible for their child's autism because they were cold parents.

The New England Center for Children feels that it is of the utmost importance to use the most effective, empirically-validated procedures. Both FC and Floortime lack scientific support, therefore we feel neither is appropriate for the children we serve. Only one intervention, applied behavior analysis (ABA), has been empirically tested and proven effective as a means for teaching children with autism the skills they need to function effectively and independent of assistance. There have been 8 controlled outcome studies showing that ABA produces substantial gains in children with autism and over 600 peer-reviewed studies demonstrating the effectiveness of ABA procedures for treating particular challenging behavior and/or remediating specific skill deficits in persons with an ASD. No other intervention has been tested with the same rigor. There is clearly much more we need to learn about the best practices for providing effective services but it is irresponsible of Time to fail to consider scientifically sound information about autism treatment.

Furthermore, several professional organizations such as the American Academy of Pediatrics and the American Psychological Association have issued position statements declaring FC an unproven treatment. FC is beyond unproven, though, it can also be quite damaging. At one point in "Inside the Autistic Mind" it is stated that "Other classic symptoms--a lack of emotion, an inability to love--can now be largely dismissed as artifacts of impaired communication. The same may be true of the supposedly high incidence of mental retardation." I'm certain that a caregiver would like to believe that a rich social and emotional life in their child can be released with simple physical assistance in typing out messages on a keyboard but that would be naive. FC has also been used as a means of lodging unsubstantiated claims of abuse against caregivers. A 1992 PBS Frontline documentary, "Prisoners of Silence" (directed by Jon Palfreman), depicts the devastation to families and false hopes brought by this technique. Perhaps this article would not have been biased towards potentially harmful interventions if they had assigned their science writers to this task.

For information on FC, go to:

http://www.apa.org/divisions/div33/fcpolicy.html
http://aappolicy.aappublications.org/cgi/content/full/pediatrics;102/2/431

Readers' Forum

Email your questions to William Ahearn.

Q: We have a child diagnosed with autism and are planning to have another child. How early would it be possible to know whether or not our next child has autism?

A: Signs of autism often seem to be apparent by around the child's first birthday. Several studies have suggested that there are behavioral differences that can be detected at one year old even though it had long been thought that a child must be at least three before autism could be diagnosed. A recent study, published by Landa and Garrett-Mayer (2006), confirms that autism can be diagnosed very early in development. Their prospective study tested over 80 infants at either high or low risk of developing autism with an early learning skills assessment and the Autism Diagnostic Observation Schedule. They tested children at 6, 14, and 24 months and found that significant signs of poor development were apparent by 14 months. However, at 14 months the high risk group performed no different than the low risk group on visual reception (e.g., pointing to a named object). By 24 months, there were differences apparent for visual reception as well. Despite this, autism still tends to be diagnosed at 4 to 5 years of age as a child comes into or is screened for kindergarten. Pediatricians, though they often screen for general development delay, do not, by and large, screen for autism. A survey published in the Journal of Developmental and Behavioral Pediatrics found that fewer than 10% of Delaware and Maryland pediatricians screen for autism (Dosreis et al., 2006). Given that siblings of a child with an ASD are at increased risk, their development should be closely monitored. Estimates of the likelihood of an affected family having another child with autism have been reported to be between 2-8% (Muhle, Trentacoste, & Rapin, 2004; Simonoff, 1998). This means that there is somewhere around a 1 in 20 chance of a couple having another child with autism. This risk is much higher than the one faced by a couple with an unaffected child but is much lower than the risk faced by a couple whose child's autism is associated with a known medical condition of genetic origin such as fragile x syndrome or tuberous sclerosis (Simonoff). Early detection is as critical to the success of early intervention as is the form that intervention takes. "Introducing behavioral interventions even one year earlier can make a tremendous difference in the lives of children with autism and their families," said Dr. Rebecca Landa, Director of the Center for Autism and Related Disorders at the Kennedy Krieger Institute in Baltimore, MD and lead author of the (prospective screening) study. "If we are able to educate professionals to identify red flags in development we can then recognize and diagnose the disorder at one-and-a-half or two years of age, instead of three or four, allowing for earlier intervention and ultimately better outcomes." (parenthetical added - quote excerpted from Science Daily, 6/2006)

Dosreis, S., Weiner, C.L., Johnson, L., & Newschaffer, C.J. (2006). Autism spectrum disorder screening and management practices among general pediatric providers. Journal of Developmental and Behavioral Pediatrics, 27(2), S88-S94.

Landa, R. & Garrett-Mayer, E. (2006). Development in infants with autism spectrum disorders: A prospective study. Journal of Child Psychology and Psychiatry, 47, 629-638.

Muhle, R., Trentacoste, S.V., & Rapin, I. (2004). The genetics of autism. Pediatrics, 113(5), e472-486.

Science Daily (6/2006, retrieved 6/1/06). Study shows autism-related developmental 'red flags' identifiable at age two in children. http://www.sciencedaily.com/releases/2006/06/060601091142.htm

Simonoff, E. (1998). Genetic counseling in autism and pervasive developmental disorders. Journal of Autism and Developmental Disorders, 28(5), 447-456.

Research at NECC

Editor's note: The New England Center for Children has recently attended the annual meeting of the Association for Behavior Analysis in Atlanta. In this issue of the newsletter, I'm including the abstracts for three of the over 30 presentations by NECC staff. The first abstract is for Becky MacDonald's talk in an invited symposium. This presentation detailed some of the collaborative work that NECC and our Shriver Center colleagues have been conducting. This work has consisted of intense study of joint attention skills in both children with autism and typically developing children. Joint attention is a reliable correlate of the social deficits inherent in autism.

Analysis and Treatment of Joint Attention in Young Children with Autism. REBECCA P. F. MACDONALD (The New England Center for Children), William V. Dube (UMMS Shriver Center), Jennifer L. Klein, Sally N. Roberts, and Krista Smaby (New England Center for Children), and Emily Wheeler (UMMC Shriver Center)

This paper will describe a contingency analysis of joint attention in which the characteristic gaze shifts, gestures, vocalizations, are shaped and maintained by conditioned socially mediated reinforcers. According to this analysis, joint attention deficits in children with autism spectrum disorders may be related to failures of socially mediated consequences to function as conditioned reinforcers. Profiles of child performance will be shown using data from a concurrent choice procedure used to determine the value of social reinforcers, as well as, assessment data on joint attention initiations and responsiveness to joint attention bids. The assessments were administered to both children diagnosed with autism spectrum disorders and typically developing children, aged 2 to 4 years. Interobserver agreement was high for all behavioral measures. Case examples of intervention procedures to establish joint attention initiations will be presented. Results will be discussed in the context of the posited behavioral contingency analysis of joint attention.

Editor's note: The next abstract is a study by Liz Christensen and Jason Bourret. This study involved assessing and treating stereotypic behavior while analyzing the effects of the treatment on both stereotypy and appropriate behavior. They showed that stereotypy could be treated without hindering performance in academic tasks.

Selective Effects of Noncontingent Access to Reinforcers "Matched" to Problem Behavior on Problem Behavior and Academic Behavior. ELIZABETH CHRISTENSEN (New England Center for Children) and Jason Bourret (New England Center for Children)

Noncontingent access to sources of reinforcement matched to the putative sensory consequence maintaining automatically reinforced problem behavior has been shown to be an effective treatment. In the present study, a functional analysis indicated that the problem behavior (stereotypy) of two participants diagnosed with autism was automatically maintained. A competing-items assessment showed that noncontingent music suppressed vocal stereotypy in both participants. The effects of noncontingent music on stereotypy and engagement in academic responding in a classroom setting were examined using a multielement design. The results showed that noncontingent access to reinforcement matched to the hypothesized sensory consequence maintaining problem behavior produced decreases in stereotypy but no decreases in rates of trial completion or accuracy of responding.

Editor's note: The last abstract is of a study conducted by Carly Moher and Dan Gould. In this study, a technique for establishing an effective motivational system is described and some of the variables that can affect these systems are explored.

Token Training and Motivating Operation Effects on the Outcomes of Preference and Reinforcer Assessments. CARLY A. MOHER (The New England Center for Children, Northeastern University), D. Daniel Gould (New England Center for Children), Richard B. Graff (New England Center for Children), and Jason Bourret (New England Center for Children)

Preference assessments have been shown to be effective procedures for identifying potential reinforcers. Typically, the stimuli included in preference assessments are limited to edible or activity items, rather than conditioned reinforcers (e.g., tokens). The present studies made use of preference- and reinforcer-assessment procedures to evaluate the reinforcing efficacy of tokens as they were being established as conditioned reinforcers (Experiment 1). Three participants underwent a series of paired-stimulus preference assessments with edibles and tokens. In token training, novel stimuli were paired repeatedly with either the participants' highest- or lowest-preferred edible items. Reinforcer assessments were carried out using a multi-element design across conditions of baseline, novel tokens, and conditioned tokens. Following this, the effects of motivating operations on the reinforcing effectiveness of tokens was tested (Experiment 2). The reinforcing effectiveness of tokens and edibles was assessed in an ABAB design. Controlled-access and satiation conditions were compared. Results for Experiment 1 indicated that the tokens were effectively established as conditioned reinforcers. Results for Experiment 2 indicated that reinforcer effectiveness decreased for both edibles and tokens during satiation relative to the controlled-access condition.

Web Resources

• For information about the New England Center or to access and electronic version of this or previous NECC Research Newsletters, visit our Web site www.necc.org.
• For information about autism, visit the National Library of Medicine's autism site www.nlm.nih.gov/medlineplus/autism.html.
• For information about applied behavior analysis in the treatment for autism visit www.behavior.org.
• For science-based information on biomedical treatments and theories in autism visit www.autism-biomed.org.
• For information on health issues in general visit the World Health Organization www.who.int.
• For professionally-screened information on health care (including some treatments for autism and other developmental disabilities), visit www.quackwatch.com.
• For information on the Berkshire Association for Behavior Analysis and Therapy, visit http://www.babat.org.
• For information on the Association for Behavior Analysis, visit http://www.abainternational.org/.

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