Autism Spectrum Disorders and Intellectual Disability

Part of the Autism and Child Psychopathology Series book series (ACPS)

Abstract

There is a significant overlap between autism spectrum disorders (ASDs) and intellectual disability (ID). In this chapter, we review this co-occurring relationship. We choose to tackle this task by examining issues related to definition and classification, biological underpinnings, and epidemiology. We then discuss the impact of level of functioning on the presentation of ASDs and their associated features as well as the similarities and differences between the two disabilities in terms of psychopathology and adaptive behavior. This chapter is not meant to be a comprehensive review of the literature. Rather, it is meant to provide a summary of relevant and contemporary studies on these selected themes.

References

  1. Abrahams, B. S., & Geschwind, D. H. (2008). Advances in autism genetics: On the threshold of a new neurobiology. Nature Reviews, Genetics, 9, 341–355.CrossRefGoogle Scholar
  2. Aman, M. G., Tassé, M. J., Rojahn, J., & Hammer, D. (1996). The Nisonger CBRF: A child behavior rating form for children with developmental disabilities. Research in Developmental Disabilities, 17, 41–57.PubMedCrossRefGoogle Scholar
  3. American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed., Text Revisions). Washington, DC: Author.Google Scholar
  4. Amiet, C., Gourfinkel-An, I., Bouzamondo, A., Tordjman, S., Baulac, M., Lechat, P., et al. (2008). Epilepsy in autism is associated with intellectual disability and gender: Evidence from a meta-analysis. Biological Psychiatry, 64, 577–582.PubMedCrossRefGoogle Scholar
  5. Bailey, A., Bolton, P., Butler, L., Le Couteur, A., Murphy, M., Scott, S., et al. (1993). Prevalence of the Fragile X anomaly amongst autistic twins and singletons. Journal of Child Psychology and Psychiatry, 34, 673–688.PubMedCrossRefGoogle Scholar
  6. Bellack, A. S., & Hersen, M. (1998). Behavioral assessment: A practical handbook (4th ed.). Needham Heights, MA: Allyn & Bacon.Google Scholar
  7. Ben Itzchak, E., Lahat, E., Burgin, R., & Zachor, A. D. (2008). Cognitive, behavior, and intervention outcome in young children with autism. Research in Developmental Disabilities, 29, 447–458.PubMedCrossRefGoogle Scholar
  8. Ben Itzchak, E., & Zachor, A. D. (2007). The effects of intellectual functioning and autism severity on outcome of early behavioral intervention for children with autism. Research in Developmental Disabilities, 28, 287–303.PubMedCrossRefGoogle Scholar
  9. Berument, S. L., Rutter, M., Lord, C., Pickles, A., & Bailey, A. (1999). Autism screening questionnaire: Diagnostic validity. British Journal of Psychiatry, 175, 444–451.PubMedCrossRefGoogle Scholar
  10. Bishop, S. L., Richler, J., & Lord, C. (2006). Association between restricted and repetitive behaviors and nonverbal IQ in children with autism spectrum disorders. Clinical Neuropsychology, 12, 247–267.CrossRefGoogle Scholar
  11. Black, D. O., Wallace, G. L., Sokoloff, J. L., & Kenworthy, L. (2009). Brief report: IQ split predicts social symptoms and communication abilities in high-functioning children with autism spectrum disorders. Journal of Autism and Developmental Disabilities, 39, 1613–1619.CrossRefGoogle Scholar
  12. Bodfish, J. W., Symons, F. J., Parker, D. E., & Lewis, M. H. (2000). Varieties of repetitive behaviors in autism: Comparisons to mental retardation. Journal of Autism and Developmental Disorders, 30, 237–243.PubMedCrossRefGoogle Scholar
  13. Bradley, E. A., & Bolton, P. (2006). Episodic psychiatric disorders in teenagers with learning disabilities with and without autism. British Journal of Psychiatry, 189, 361–366.PubMedCrossRefGoogle Scholar
  14. Bradley, E. A., & Isaacs, B. J. (2006). Inattention, hyperactivity, and impulsivity in teenagers with intellectual disabilities, with and without autism. Canadian Journal of Psychiatry, 51, 598–606.Google Scholar
  15. Bradley, E. A., Summers, J. A., Wood, H. L., & Bryson, S. E. (2004). Comparing rates of psychiatric and behavior disorders in adolescents and young adults with severe intellectual disability with and without autism. Journal of Autism and Developmental Disorders, 34, 151–161.PubMedCrossRefGoogle Scholar
  16. Brereton, A. V., Tonge, B. J., & Einfeld, S. L. (2006). Psychopathology in children and adolescents with autism compared to young people with intellectual disability. Journal of Autism and Developmental Disorders, 36, 863–870.PubMedCrossRefGoogle Scholar
  17. Bryson, S. E., Bradley, E. A., Thompson, A., & Wainwright, A. (2008). Prevalence of autism among adolescents with intellectual disabilities. The Canadian Journal of Psychiatry, 53, 449–459.Google Scholar
  18. Bryson, S. E., & Smith, I. M. (1998). Epidemiology of autism: Prevalence, associated characteristics, and implications for research and service delivery. Mental Retardation and Developmental Disabilities Research Reviews, 4, 97–103.CrossRefGoogle Scholar
  19. Buitelaar, J. K., Van der Gaag, R., Klin, A., & Volkmar, F. R. (1999). Exploring the boundaries of pervasive developmental disorder not otherwise specified: Analyses of data from the DSM-IV autistic disorder field trial. Journal of Autism and Developmental Disorders, 29, 33–43.PubMedCrossRefGoogle Scholar
  20. Caniato, R. (2007). Epilepsy in autism spectrum disorders. European Child and Adolescent Psychiatry, 16, 61–66.CrossRefGoogle Scholar
  21. Carcani-Rathwell, I., Hasketh-Rabe, S., & Santosh, P. J. (2006). Repetitive and stereotyped behaviors in pervasive developmental disorders. Journal of Child Psychology and Psychiatry, 47, 573–581.PubMedCrossRefGoogle Scholar
  22. Center for Disease Control and Prevention. (2009). Autism and developmental disorders monitoring network. Retrieved March 18, 2010, from http://www.cdc.gov/ncbddd/autism/addm.html
  23. Chakrabarti, S., & Fombonne, E. (2001). Pervasive developmental disorders in preschool children. Journal of the American Medical Association, 285, 3093–3099.PubMedCrossRefGoogle Scholar
  24. Chakrabarti, S., & Fombonne, E. (2005). Pervasive developmental disorders in preschool children: Confirmation of high prevalence. American Journal of Psychiatry, 162, 1133–1141.PubMedCrossRefGoogle Scholar
  25. Charman, T., Pickles, A., Chandler, S., Wing, L., Bryson, S., Simonoff, E., et al. (2009). Commentary: Effects of diagnostic thresholds and research vs service and administrative diagnosis on autism prevalence. International Journal of Epidemiology, 38, 1234–1238.PubMedCrossRefGoogle Scholar
  26. Constantino, J. (2002). The social responsiveness scale. Los Angeles: Western Psychological Services.Google Scholar
  27. Constantino, J. N., Davis, S. A., Todd, R. D., Schindler, M. K., Gross, M. M., Brophy, S. L., et al. (2003). Validation of a brief quantitative measure of autistic traits: Comparison of the social responsiveness scale with the Autism Diagnostic Interview-Revised. Journal of Autism and Developmental Disorders, 33, 427–433.PubMedCrossRefGoogle Scholar
  28. Croen, L. A., Grether, J. K., Hoogstrate, J., & Selvin, S. (2002). The changing prevalence of autism in California. Journal of Autism and Developmental Disorders, 32, 207–215.PubMedCrossRefGoogle Scholar
  29. Cuccaro, M. L., Shao, Y., Grubber, J., Slifer, M., Wolpert, C. M., Donnelly, S. L., et al. (2003). Factor analysis of restricted and repetitive behaviors in autism using the Autism Diagnostic Interview – R. Child Psychiatry and Human Development, 34, 3–17.PubMedCrossRefGoogle Scholar
  30. Dawson, G., Estes, A., Munson, J., Schellenberg, G., Bernier, R., & Abbott, R. (2007). Quantitative assessment of autism symptom-related traits in probands and parents: Broader phenotype autism assessment scale. Journal of Autism and Developmental Disorders, 37, 523–536.PubMedCrossRefGoogle Scholar
  31. de Bildt, A., Sytema, S., Ketelaars, C., Kraijer, D., Mulder, E., Volkmar, F., et al. (2004). Interrelationship between the Autism Diagnostic Observation Schedule-Generic (ADOS-G), Autism Diagnostic Interview-Revised (ADI-R), and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) classification in children and adolescents with mental retardation. Journal of Autism and Developmental Disorders, 34, 129–137.PubMedCrossRefGoogle Scholar
  32. De Bildt, A., Sytema, S., Kraijer, D., & Monderra, R. (2005). Prevalence of pervasive developmental disorders in children and adolescents with mental retardation. Journal of Child Psychology and Psychiatry, 46, 275–286.PubMedCrossRefGoogle Scholar
  33. DiLavore, P. C., Lord, C., & Rutter, M. (1995). The prelinguistic autism diagnostic observation schedule. Journal of Autism and Developmental Disorders, 25, 355–379.PubMedCrossRefGoogle Scholar
  34. Eisenhower, A. S., Baker, B. L., & Blancher, J. (2005). Preschool children with intellectual disability: Syndrome specificity, behavior problems, and maternal well-being. Journal of Intellectual Disability Research, 49, 657–671.PubMedCrossRefGoogle Scholar
  35. Estes, A. M., Dawson, G., Sterling, L., & Munson, J. (2007). Level of intellectual functioning predicts patterns of associated symptoms in school-age children with autism spectrum disorder. American Journal on Mental Retardation, 112, 439–449.PubMedCrossRefGoogle Scholar
  36. Fombonne, E. (2003). Epidemiological surveys of autism and other pervasive developmental disorders: An update. Journal of Autism and Developmental Disorders, 33, 365–382.PubMedCrossRefGoogle Scholar
  37. Fombonne, E. (2005a). Epidemiological studies of pervasive developmental disorders. In F. R. Volkmar, R. Paul, A. Klin, & D. Cohen (Eds.), Handbook of autism and pervasive developmental disorders (pp. 42–69). Hoboken, NJ: Wiley.Google Scholar
  38. Fombonne, E. (2005b). Epidemiology of Autistic Disorder and other pervasive Developmental Disorders. Journal of Clinical Psychiatry, 66(Supplement 10), 3–8.PubMedGoogle Scholar
  39. Fombonne, E. (2005c). The changing epidemiology of autism. Journal of Applied Research in Intellectual Disabilities, 18, 281–294.CrossRefGoogle Scholar
  40. Gadow, K. D., DeVincent, C. J., Pomeroy, J., & Azizian, A. (2004). Psychiatric symptoms in preschool children with PDD and clinic and comparison samples. Journal of Autism and Developmental Disorders, 34, 379–393.PubMedCrossRefGoogle Scholar
  41. Gadow, K. D., DeVincent, C. J., Pomeroy, J., & Azizian, A. (2005). Comparison of DSM-IV symptoms in elementary school-age children with PDD versus clinic and community. Autism, 9, 392–415.PubMedCrossRefGoogle Scholar
  42. Gillberg, C., & Billstedt, E. (2000). Autism and Asperger’s syndrome: Coexistence with other clinical disorders. Acta Psychiatrica Scandanavia, 102, 321–330.CrossRefGoogle Scholar
  43. Gilliam, J. E. (2006). Gilliam autism rating scale (2nd ed.). Austin: ProEd.Google Scholar
  44. Hastings, R. P., Daley, D., Burns, C., & Beck, A. (2006). Maternal distress and expressed emotion: Cross-sectional and longitudinal relationships with behavior problems of children with intellectual disabilities. American Journal on Mental Retardation, 111, 48–61.PubMedCrossRefGoogle Scholar
  45. Hauser, W. A., Annegers, J. F., & Kurland, L. T. (1991). Prevalence of epilepsy in Rochester, Minnesota: 1940–1980. Epilepsia, 32, 429–445.PubMedCrossRefGoogle Scholar
  46. Helt, M., Kelley, E., Kinsbourne, M., Pandey, J., Boorstein, H., Herbert, M., et al. (2008). Can children with autism recover? If so, how? Neuropsychology Review, 18, 339–366.PubMedCrossRefGoogle Scholar
  47. Hill, J., & Furniss, F. (2006). Patterns of emotional and behavioral disturbance associated with autistic traits in young people with severe intellectual disabilities and challenging behaviors. Research in Developmental Disabilities, 27, 517–528.PubMedCrossRefGoogle Scholar
  48. Hoekstra, R. A., Happé, F., Baron-Cohen, S., & Ronald, A. (2009). Association between extreme sutistic traits and intellectual disability. British Journal of Psychiatry, 195, 531–536.PubMedCrossRefGoogle Scholar
  49. Howlin, P., Goode, S., Hutton, J., & Rutter, M. (2004). Adult outcome for children with autism. Journal of Child Psychology and Psychiatry, 45, 212–229.PubMedCrossRefGoogle Scholar
  50. Joseph, R. M., Tager-Flusberg, H., & Lord, C. (2002). Cognitive profiles and social-communication functioning in children with autism spectrum disorder. Journal of Child Psychology and Psychiatry, 43, 807–821.PubMedCrossRefGoogle Scholar
  51. Kim, J. A., Szatmari, P., Bryson, S. E., Streiner, D. L., & Wilson, F. J. (2000). The prevalence of anxiety and mood problems among children with autism and Asperger syndrome. Autism, 4, 117–132.CrossRefGoogle Scholar
  52. King, M., & Bearman, P. (2009). Diagnostic change and the increased prevalence of autism. International Journal of Epidemiology, 38, 1224–1234.PubMedCrossRefGoogle Scholar
  53. Klin, A., Jones, W., Schultz, R., & Volkmar, F. R. (2003). The enactive mind, or from actions to cognition: Lessons from autism. Philosophical Transactions of the Royal Society of London – Series B: Biological Sciences, 358, 345–360.PubMedCrossRefGoogle Scholar
  54. Kogan, M. D., Blumberg, S. J., Schieve, L. A., Boyle, C. A., Perrin, J. M., Ghandour, R. M., et al. (2009). Prevalence of parent-reported diagnosis of autism spectrum disorder among children in the US, 2007. Pediatrics. doi:10.1542/peds.2009–1522.Google Scholar
  55. Lainhart, J. E., & Folstein, S. E. (1994). Affective disorders in people with autism: A review of published cases. Journal of Autism and Developmental Disorders, 24, 587–601.PubMedCrossRefGoogle Scholar
  56. Lecavalier, L. (2006). Behavioral and emotional problems in young people with pervasive developmental disorders: Relative prevalence, effects of subject characteristics, and empirical classification. Journal of Autism and Developmental Disorders, 36, 1101–1114.PubMedCrossRefGoogle Scholar
  57. Lecavalier, L., & Butter, E. M. (2010). Assessment of social skills and intellectual disability. In D. Nangle, D. Hansen, C. Erdley, & P. J. Norton (Eds.), Practitioner’s guide to empirically-based measures of social skills (pp. 179–192). New York: Association for the Advancement of Behavior Therapy and Springer.CrossRefGoogle Scholar
  58. Lecavalier, L., Gadow, K., DeVincent, C. J., & Edwards, M. C. (2009). Validation of DSM-IV model of psychiatric syndromes in children with autism spectrum disorders. Journal of Autism and Developmental Disorders, 39, 278–289.PubMedCrossRefGoogle Scholar
  59. Lee, J. H., Larson, S. A., Lakin, C., Anderson, L., Nohoon, K. L., & Anderson, D. (2001). Prevalence of mental retardation and developmental disabilities: Estimates from the 1994/1995 national health interview survey disability supplements. American Journal on Mental Retardation, 106, 231–252.PubMedCrossRefGoogle Scholar
  60. Leonard, H., Petterson, B., De Clerk, N., Zubrick, S. R., Glasson, E., Sanders, R., et al. (2005). Association of sociodemographic characteristics of children with intellectual disability in Western Australia. Social Science & Medicine, 60, 1499–1513.CrossRefGoogle Scholar
  61. Levis, S. E., Mandell, D. S., & Schultz, R. T. (2009). Autism. Lancet, 374, 1627–1638.CrossRefGoogle Scholar
  62. Lord, C., & Corsello, C. (2005). Diagnostic instruments in autistic spectrum disorders. In F. R. Volkmar, R. Paul, A. Klin, & D. Cohen (Eds.), Handbook of autism and pervasive developmental disorders (pp. 730–771). Hoboken, NJ: Wiley.Google Scholar
  63. Lord, C., Risi, S., Lambrecht, L., Cook, E. H., Leventhal, B. L., DiLavore, P. C., et al. (2000). The Autism Diagnostic Observation Schedule-Generic: A standard measure of social and communication deficits associated with the spectrum of autism. Journal of Autism and Developmental Disorders, 30, 205–223.PubMedCrossRefGoogle Scholar
  64. Lord, C., Rutter, M., & LeCouteur, A. (1994). The Autism Diagnostic Interview-Revised: A revised version of a diagnostic interview for caregivers of individuals with possible pervasive developmental disorders. Journal of Autism and Developmental Disorders, 24, 659–685.PubMedCrossRefGoogle Scholar
  65. Lord, C., Schopler, E., & Revicki, D. (1982). Sex differences in autism. Journal of Autism and Developmental Disorders, 12, 317–330.PubMedCrossRefGoogle Scholar
  66. Luyster, R., Qiu, S., Lopez, K., & Lord, C. (2007). Predicting outcomes of children referred for autism using the MacArthur-Bates communication inventory. Journal of Speech, Language, and Hearing Research, 50, 667–681.PubMedCrossRefGoogle Scholar
  67. Matson, J. L., Boisjoli, J. A., Gonzalez, M. L., Smith, K. R., & Wilkins, J. (2007). Norms and cut off scores for the autism spectrum disorders diagnosis for adults (ASD-DA) with intellectual disability. Research in Autism Spectrum Disorders, 1, 330–338.CrossRefGoogle Scholar
  68. Matson, J. L., Dempsey, T., & Fodstad, J. C. (2009). The effect of autism spectrum disorders on adaptive independent living skills in adults with severe intellectual disability. Research in Developmental Disabilities, 30, 1203–1211.PubMedCrossRefGoogle Scholar
  69. Matson, J. L., Dempsey, T., LoVullo, S. V., & Wilkins, J. (2008). The effects of intellectual functioning on the range of core symptoms in autism spectrum disorders. Research in Developmental Disabilities, 29, 341–350.PubMedCrossRefGoogle Scholar
  70. Matson, J. L., & Nebel-Schwalm, M. S. (2007). Comorbid psychopathology with autism spectrum disorder in children: An overview. Research in Developmental Disabilities, 28, 341–352.PubMedCrossRefGoogle Scholar
  71. Matson, J. L., Rivet, T. T., Fodstad, J. C., Dempsey, T., & Boisjoli, J. A. (2009). Examination of adaptive behavior differences in adults with autism spectrum disorders and intellectual disability. Research in Developmental Disabilities, 30, 1317–1325.PubMedCrossRefGoogle Scholar
  72. Matson, J. L., & Shoemaker, M. (2009). Intellectual disability and its relationship to autism spectrum disorders. Research in Developmental Disabilities, 30, 1107–1114.PubMedCrossRefGoogle Scholar
  73. Matson, J. L., Wilkins, J., & Ancona, M. (2008). Autism in adults with severe intellectual disability: An empirical study of symptom presentation. Journal of Intellectual and Developmental Disability, 33, 36–42.PubMedCrossRefGoogle Scholar
  74. Matson, J. L., Wilkins, J., Boisjoli, J. A., & Smith, K. R. (2008). The validity of the autism spectrum disorders-diagnosis for intellectually disabled adults (ASD-DA). Research in Developmental Disabilities, 29, 537–546.PubMedCrossRefGoogle Scholar
  75. Matson, J. L., Wilkins, J., & Gonzalez, M. L. (2007). Reliability and factor structure of the Autism Spectrum Disorders–Diagnosis for Intellectually Disabled Adults (ASD-DA). Journal of Developmental and Physical Disabilities, 1, 565–577.CrossRefGoogle Scholar
  76. McClintock, K., Hall, S., & Oliver, C. (2003). Risk markers associated with challenging behaviors in people with intellectual disabilities: A meta-analytic study. Journal of Intellectual Disability Research, 47, 405–416.PubMedCrossRefGoogle Scholar
  77. McDougle, C. J., Kresch, L. E., Goodman, W. K., Naylor, S. T., Volkmar, F. R., Cohen, D. J., et al. (1995). A case-controlled study of repetitive thoughts and behavior in adults with autistic disorder and obsessive-compulsive disorder. American Journal of Psychiatry, 152, 772–777.PubMedGoogle Scholar
  78. McGovern, C. W., & Sigman, M. (2005). Continuity and change from early childhood to adolescence in autism. Journal of Child Psychology and Psychiatry, 46, 401–408.PubMedCrossRefGoogle Scholar
  79. Munson, J., Dawson, G., Sterling, L., Beauchaine, T., Zhou, A., Koehler, E., et al. (2008). Evidence for latent classes of IQ in young children with autism spectrum disorder. American Journal on Mental Retardation, 113, 439–452.PubMedCrossRefGoogle Scholar
  80. Nordin, V., & Gillberg, C. (1996). Autism spectrum disorders in children with physical or mental disability or both. I: Clinical and epidemiological aspects. Developmental Medicine and Child Neurology, 38, 297–313.PubMedCrossRefGoogle Scholar
  81. Norris, M., & Lecavalier, L. (2010). Screening accuracy of level 2 Autism Spectrum Disorder rating scales: A review of selected instruments. Autism, 14, 263–284.Google Scholar
  82. Palmer, R. F., Blanchard, S., Jean, C. R., & Mandell, D. S. (2005). School district resources and identification of children with autistic disorder. American Journal of Public Health, 95, 125–130.PubMedCrossRefGoogle Scholar
  83. Pine, E., Luby, J., Abbacchi, A., & Constantino, J. N. (2006). Quantitative assessment of autistic symptomatology in preschoolers. Autism, 10, 344–352.PubMedCrossRefGoogle Scholar
  84. Remington, B., Hastings, R. P., Kovshoff, H., degli Espinosa, F., Jahr, E., Brown, T., et al. (2007). Early intensive behavioral intervention: Outcomes for children with autism and their parents after two years. American Journal on Mental Retardation, 112, 418–438.PubMedCrossRefGoogle Scholar
  85. Robins, E., & Guze, S. B. (1970). Establishment of diagnostic validity in psychiatric illness: Its application to schizophrenia. American Journal of Psychiatry, 126, 983–987.PubMedGoogle Scholar
  86. Roeleveld, N., Zielhuis, G. A., & Gabreels, F. (1997). The prevalence of mental retardation: A critical review of recent literature. Developmental Medicine and Child Neurology, 39, 125–132.PubMedCrossRefGoogle Scholar
  87. Rutter, M. (2009). Commentary: Fact and artifact in the secular increase in the rate of autism. International Journal of Epidemiology, 38, 1238–1239.PubMedCrossRefGoogle Scholar
  88. Sallows, G. O., & Graupner, T. D. (2005). Intensive behavioral treatment for children with autism: Four-year outcome and predictors. American Journal on Mental Retardation, 110, 417–438.PubMedCrossRefGoogle Scholar
  89. Scott, F. J., Baron-Cohen, S., Bolton, P., & Brayne, C. (2002). Brief report: Prevalence of autism spectrum conditions in children aged 5–11 years in Cambridgeshire, UK. Autism, 6, 231–237.PubMedCrossRefGoogle Scholar
  90. Seltzer, M. M., Shattuck, P., Abbeduto, L., & Greenberg, J. S. (2004). Trajectory of development in adolescents and adults with autism. Mental Retardation and Developmental Disabilities Research Reviews, 10, 234–247.PubMedCrossRefGoogle Scholar
  91. Shattuck, P. T. (2006). The contribution of diagnostic substitution to the growing administrative prevalence of autism in US special education. Pediatrics, 117, 1028–1037.PubMedCrossRefGoogle Scholar
  92. Shattuck, P. T., Seltzer, M. M., Greenberg, J. S., Orsmond, G. I., Bolt, D., Kring, S., et al. (2007). Change in autism symptoms and maladaptive behaviors in adolescents and adults with an autism spectrum disorder. Journal of Autism and Developmental Disorders, 37, 1735–1747.PubMedCrossRefGoogle Scholar
  93. Simonoff, E., Pickles, A., Charman, T., Chandler, S., Loucas, T., & Baird, G. (2008). Psychiatric disorders in children with autism spectrum disorders: Prevalence, comorbidity, and associated factors in a population-derived sample. Journal of the American Academy of Child and Adoelscent Psychiatry, 47, 921–929.CrossRefGoogle Scholar
  94. Skuse, D. H. (2006). Genetic influences on the neural basis of social cognition. Philosophical Transactions of the Royal Society of London Biological Sciences, 361, 2129–2141.CrossRefGoogle Scholar
  95. Skuse, D. H. (2007). Rethinking the nature of genetic vulnerability to autistic spectrum disorders. Trends in Genetics, 8, 387–395.CrossRefGoogle Scholar
  96. Smalley, S. L. (1998). Autism and tuberous sclerosis. Journal of Autism and Developmental Disorders, 28, 407–414.PubMedCrossRefGoogle Scholar
  97. Sparrow, S. S., Cicchetti, D. V., & Balla, D. A. (2005). Vineland adaptive behavior scales – Second edition: Survey forms manual. Circle Pines, MN: AGS Publishing.Google Scholar
  98. Spiker, D., Lotspeich, L. J., Dimiceli, S., Myers, R. M., & Risch, N. (2002). Behavioral phenotypic variation in autism multiplex familes: Evidence for a continuous severity gradient. American Journal of Medical Genetics (Neuropsychiatric Genetics), 114, 129–136.CrossRefGoogle Scholar
  99. Sponheim, E., & Skjeldal, O. (1998). Autism and related disorders: Epidemiological findings in a Norwegian study using ICD-10 diagnostic criteria. Journal of Autism and Developmental Disorders, 28, 217–227.PubMedCrossRefGoogle Scholar
  100. Sukhodolsky, D. G., Scahill, L., Gadow, K. G., Arnold, L. E., Aman, M. G., McDougle, C. J., et al. (2008). Parent-rated anxiety symptoms in children with pervasive developmental disorders: Frequency and association with core autism symptoms and cognitive functioning. Journal of Abnormal Child Psychology, 36, 117–128.PubMedCrossRefGoogle Scholar
  101. Szatmari, P., Bryson, S. E., Boyle, M. H., Streiner, D. L., & Duku, E. (2003). Predictors of outcome among high functioning children with autism and Asperger syndrome. Journal of Child Psychology and Psychiatry, 44, 520–528.PubMedCrossRefGoogle Scholar
  102. Szatmari, P., Georgiades, S., Bryson, S., Zwaigenbaum, L., Roberts, W., Mahoney, W., et al. (2006). Investigating the structure of the restricted, repetitive behaviors and interests domain of autism. Journal of Child Psychology and Pscyiatry, 47, 582–590.CrossRefGoogle Scholar
  103. Tager-Flusberg, H., & Joseph, R. M. (2003). Identifying neurocognitive phenotypes in autism. Philosophical Transactions of the Royal Society of London, Biological Science, 358, 303–314.CrossRefGoogle Scholar
  104. Tonge, B. J., & Einfeld, S. L. (2003). Psychopathology and intellectual disability: The Australian child to adult longitudinal study. International Review of Research in Mental Retardation, 26, 61–91.CrossRefGoogle Scholar
  105. Tsakanikos, E., Costello, H., Holt, G., Bouras, N., Sturmey, P., & Newton, T. (2006). Psychopathology in adults with autism and intellectual disability. Journal of Autism and Developmental Disorders, 36, 1123–1129.PubMedCrossRefGoogle Scholar
  106. Tuchman, R., & Rapin, I. (2002). Epilepsy in autism. Lancet Neurology, 1, 352–358.PubMedCrossRefGoogle Scholar
  107. Van Meter, K. C., Christiansen, L. E., Delwiche, L. D., Azari, R., Carpenter, T. E., & Hertz-Picciotto, I. (2010). Geographic distribution of autism in California: A retrospective birth cohort analysis. Autism Research. doi:10.1002/aur.110.Google Scholar
  108. Volkmar, F. R. (2002). Predicting outcome in autism. Journal of Autism and Developmental Disorders, 32, 63–64.PubMedCrossRefGoogle Scholar
  109. Wesibrot, D. M., Gadow, K. D., DeVincent, C. J., & Pomeroy, J. (2005). The presentation of anxiety in children with pervasive developmental disorders. Journal of Child and Adolescent Psychopharmacology, 15, 477–496.CrossRefGoogle Scholar
  110. Westerinen, H., Kaski, M., Virta, L., Almqvist, F., & Livanainen, M. (2007). Prevalence of intellectual disability: A comprehensive study based on national registers. Journal of Intellectual Disability Research, 51, 715–725.PubMedCrossRefGoogle Scholar
  111. Wilkins, J., & Matson, J. L. (2009). A comparison of social skills profiles in intellectually disabled adults with and without ASD. Behavior Modification, 33, 143–155.PubMedCrossRefGoogle Scholar
  112. Wing, L., & Gould, J. (1979). Severe impairments of social interaction and associated abnormalities in children: Epidemiology and classification. Journal of Autism and Developmental Disorders, 9, 11–29.PubMedCrossRefGoogle Scholar
  113. Witwer, A. N., & Lecavalier, L. (2008a). Validity of autism spectrum disorder subtypes. Journal of Autism and Developmental Disorders, 38, 1611–1624.PubMedCrossRefGoogle Scholar
  114. Witwer, A. N., & Lecavalier, L. (2008b). Psychopathology in children with intellectual disability: Risk markers and correlates. Journal of Mental Health Research and Intellectual Disabilities, 1, 75–96.CrossRefGoogle Scholar
  115. Witwer, A. N., & Lecavalier, L. (2010). Validity of comorbid psychiatric disorders in children with autism spectrum disorders. Journal of Developmental and Physical Disabilities, 22, 367–380.Google Scholar
  116. Yeargin-Allsopp, M., Rice, C., Karapurkar, T., Doernberg, N., Boyle, C., & Murphy, C. (2003). Prevalence of autism in a US metropolitan area. Journal of the American Medical Association, 289, 49–55.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Ohio State UniversityColumbusUSA
  2. 2.Child Study Center, Yale UniversityNew HavenUSA
  3. 3.University of Rochester Medical CenterRochesterUSA

Personalised recommendations