Neuropsychology Review

, Volume 18, Issue 4, pp 287–304 | Cite as

The ‘Fractionable Autism Triad’: A Review of Evidence from Behavioural, Genetic, Cognitive and Neural Research

Article

Abstract

Autism is diagnosed on the basis of a triad of impairments in social interaction, communication, and flexible imaginative functions (with restricted and repetitive behaviors and interests; RRBIs). There has been a strong presumption that these different features of the syndrome are strongly intertwined and proceed from a common cause at the genetic, cognitive and neural levels. In this review we examine evidence for an alternative approach, considering the triad as largely ‘fractionable’. We present evidence from our own twin studies, and review relevant literature on autism and autistic-like traits in other groups. We suggest that largely independent genes may operate on social skills/impairments, communication abilities, and RRBIs, requiring a change in molecular-genetic research approaches. At the cognitive level, we suggest that satisfactory accounts exist for each of the triad domains, but no single unitary account can explain both social and nonsocial features of autism. We discuss the implications of the fractionable-triad approach for both diagnosis and future research directions.

Keywords

Autism Autism spectrum disorders Cognitive theories Fractionation Twin studies 

References

  1. Abell, F., Krams, M., Ashburner, J., Passingham, R., Friston, K., Frackowiak, R., et al. (1999). The neuroanatomy of autism: a voxel-based whole brain analysis of structural scans. Neuroreport, 10(8), 1647–1651.PubMedGoogle Scholar
  2. Abrahams, B. S., & Geschwind, D. H. (2008). Advances in autism genetics: on the threshold of a new neurobiology. Nature Reviews Genetics, 9(5), 341–355.PubMedGoogle Scholar
  3. Alarcon, M., Cantor, R. M., Liu, J., Gilliam, T. C., & Geschwind, D. H. (2002). Evidence for a language quantitative trait locus on chromosome 7q in multiplex autism families. American Journal of Human Genetics, 70(1), 60–71.PubMedGoogle Scholar
  4. Amodio, D. M., & Frith, C. D. (2006). Meeting of minds: the medial frontal cortex and social cognition. Nature Reviews Neuroscience, 7, 268–77.PubMedGoogle Scholar
  5. Arking, D. E., Cutler, D. J., Brune, C. W., Teslovich, T. M., West, K., Ikeda, M., et al. (2008). A common genetic variant in the neurexin superfamily member CNTNAP2 increases familial risk of autism. American Journal of Human Genetics, 82(1), 160–164.PubMedGoogle Scholar
  6. Austin, E. J. (2005). Personality correlates of the broader autism phenotype as assessed by the Autism Spectrum Quotient. Personality and Individual Differences, in press.Google Scholar
  7. Auyeung, B., Baron-Cohen, S., Wheelwright, S., & Allison, C. (2008). The Autism Spectrum Quotient: Children’s Version (AQ-Child). J Autism Dev Disord, 38(7), 1230–1240.PubMedGoogle Scholar
  8. Bailey, A., Le Couteur, A., Gottesman, I., Bolton, P., Simonoff, E., Yuzda, E., et al. (1995). Autism as a strongly genetic disorder: evidence from a British twin study. Psychological Medicine, 25(1), 63–77.PubMedGoogle Scholar
  9. Baron-Cohen, S., Tager-Flusberg, H., & Cohen, D. J. (Eds.). (2000). Understanding other minds: Perspectives from developmental cognitive neuroscience (2nd ed.). Oxford, England: Oxford University Press.Google Scholar
  10. Belmonte, M. K., Allen, G., Beckel-Mitchener, A., Boulanger, L. M., Carper, R. A., & Webb, S. J. (2004). Autism and abnormal development of brain connectivity. Journal of Neuroscience, 24(42), 9228–9231.PubMedGoogle Scholar
  11. Berument, S. K., Rutter, M., Lord, C., Pickles, A., & Bailey, A. (1999). Autism screening questionnaire: diagnostic validity. British Journal of Psychiatry, 175, 444–451.PubMedGoogle Scholar
  12. Best, C. S., Moffat, V. J., Power, M. J., Owens, D. G. C., & Johnstone, E. C. (2008). The boundaries of the cognitive phenotype of autism: Theory of Mind, central coherence and ambiguous figure perception in young people with autistic traits. Journal of Autism and Developmental Disorders, 38, 840–847.PubMedGoogle Scholar
  13. Betancur, C., Leboyer, M., & Gillberg, C. (2002). Increased rate of twins among affected sibling pairs with autism. American Journal of Human Genetics, 70(5), 1381–1383.PubMedGoogle Scholar
  14. Bolte, S., & Poustka, F. (2001). [Factor structure of the Autism Diagnostic Interview-Revised (ADI-R): a study of dimensional versus categorical classification of autistic disorders]. Zeitschrift für Kinder- und Jugendpsychiatrie und Psychotherapie, 29(3), 221–229.PubMedGoogle Scholar
  15. Bolton, P., Macdonald, H., Pickles, A., Rios, P., Goode, S., Crowson, M., et al. (1994). A case–control family history study of autism. Journal of Child Psychology & Psychiatry & Allied Disciplines, 35(5), 877–900.Google Scholar
  16. Booth, R., Charlton, R., Hughes, C., & Happé, F. (2003). Disentangling weak coherence and executive dysfunction: planning drawing in autism and attention-deficit/hyperactivity disorder. Philosophical Transactions of the Royal Society of London Series B, Biological Sciences, 358(1430), 387–392.PubMedGoogle Scholar
  17. Bradford, Y., Haines, J., Hutcheson, H., Gardiner, M., Braun, T., Sheffield, V., et al. (2001). Incorporating language phenotypes strengthens evidence of linkage to autism. American Journal of Medical Genetics, 105(6), 539–547.PubMedGoogle Scholar
  18. Briskman, J., Happé, F. & Frith, U. (2001). Exploring the cognitive phenotype of autism: Weak ‘central coherence’ in parents and siblings of children with autism. II. Real-life skills and preferences. Journal of Child Psychology and Psychiatry, 42, 309–316.PubMedGoogle Scholar
  19. Bruder, C. E., Piotrowski, A., Gijsbers, A. A., Andersson, R., Erickson, S., de Stahl, T. D., et al. (2008). Phenotypically concordant and discordant monozygotic twins display different DNA copy-number-variation profiles. American Journal of Human Genetics, 82(3), 763–771.PubMedGoogle Scholar
  20. Brune, C. W., Kim, S. J., Salt, J., Leventhal, B. L., Lord, C., & Cook Jr., E. H. (2006). 5-HTTLPR genotype-specific phenotype in children and adolescents with autism. American Journal of Psychiatry, 163(12), 2148–2156.PubMedGoogle Scholar
  21. Bryson, S. E., Clark, B. S., & Smith, I. M. (1988). First report of a Canadian epidemiological study of autistic syndromes. Journal of Child Psychology & Psychiatry & Allied Disciplines, 29(4), 433–445.Google Scholar
  22. Buxbaum, J. D., Silverman, J. M., Smith, C. J., Kilifarski, M., Reichert, J., Hollander, E., et al. (2001). Evidence for a susceptibility gene for autism on chromosome 2 and for genetic heterogeneity. American Journal of Human Genetics, 68(6), 1514–1520.PubMedGoogle Scholar
  23. Caron, C., & Rutter, M. (1991). Comorbidity in child psychopathology: Concepts, issues and research strategies. Journal of Child Psychology & Psychiatry & Allied Disciplines, 32(7), 1063–1080.Google Scholar
  24. Castelli, F., Frith, C., Happé, F., & Frith, U. (2002). Autism, Asperger syndrome and brain mechanisms for the attribution of mental states to animated shapes. Brain: A Journal of Neurology, 125(8), 1839–1849.Google Scholar
  25. Charman, T., Carroll, F., & Sturge, C. (2001). Theory of mind, executive function and social competence in boys with ADHD. Emotional & Behavioural Difficulties, 6(1), 31–49.Google Scholar
  26. Charman, T., Taylor, E., Drew, A., Cockerill, H., Brown, J. A., & Baird, G. (2005). “Outcome at 7 years of children diagnosed with autism at age 2: predictive validity of assessments conducted at 2 and 3 years of age and pattern of symptom change over time”, Journal of Child Psychology & Psychiatry & Allied Disciplines, vol. 46, no. 5, pp. 500–513.Google Scholar
  27. Chen, G. K., Kono, N., Geschwind, D. H., & Cantor, R. M. (2006). Quantitative trait locus analysis of nonverbal communication in autism spectrum disorder. Molecular Psychiatry, 11(2), 214–220.PubMedGoogle Scholar
  28. Constantino, J. N., Gruber, C. P., Davis, S., Hayes, S., Passanante, N., & Przybeck, T. (2004). The factor structure of autistic traits. Journal of Child Psychology & Psychiatry & Allied Disciplines, 45(4), 719–726.Google Scholar
  29. Constantino, J. N., Przybeck, T., Friesen, D., & Todd, R. D. (2000). Reciprocal social behavior in children with and without pervasive developmental disorders. Journal of Developmental and Behavioral Pediatrics, 21(1), 2–11.PubMedGoogle Scholar
  30. Croen, L. A., Grether, J. K., & Selvin, S. (2002). Descriptive epidemiology of autism in a California population: who is at risk? Journal of Autism and Developmental Disorders, 32(3), 217–224.PubMedGoogle Scholar
  31. DiLalla, D. L., & Rogers, S. J. (1994). Domains of the Childhood Autism Rating Scale: relevance for diagnosis and treatment. Journal of Autism and Developmental Disorders, 24(2), 115–128.PubMedGoogle Scholar
  32. Ehlers, S., & Gillberg, C. (1993). The epidemiology of Asperger syndrome. A total population study. Journal of Child Psychology & Psychiatry & Allied Disciplines, 34(8), 1327–1350.Google Scholar
  33. Folstein, S. E., & Rutter, M. (1977). Genetic influences and infantile autism. Nature, 265(5596), 726–728.PubMedGoogle Scholar
  34. Freeman, B. J., Schroth, P., Ritvo, E., Guthrie, D., & Wake, L. (1980). The Behavior Observation Scale for autism (BOS): initial results of factor analysis. Journal of Autism and Developmental Disorders, 10(3), 343–346.PubMedGoogle Scholar
  35. Frith, U. (1989). Autism: explaining the Enigma. Oxford, Blackwell.Google Scholar
  36. Frith, C. (2003). What do imaging studies tell us about the neural basis of autism? Novartis Foundation Symposium, 251, 149–66 discussion 166–76, 281–97.PubMedGoogle Scholar
  37. Frith, U., & Happé, F. (1994). Autism: beyond ‘‘theory of mind’’. Cognition, 50, 115–132.PubMedGoogle Scholar
  38. 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 samples. Autism, 9(4), 392–415.PubMedGoogle Scholar
  39. Geurts, H. M., Verte, S., Oosterlaan, J., Roeyers, H., & Sergeant, J. A. (2004). How specific are executive functioning deficits in attention deficit hyperactivity disorder and autism? Journal of Child Psychology and Psychiatry, 45, 836–854.PubMedGoogle Scholar
  40. Goin-Kochel, R. P., Mazefsky, C. A., & Riley, B. P. (2008). Level of functioning in autism spectrum disorders: phenotypic congruence among affected siblings. Journal of Autism and Developmental Disorders, 38(6), 1019–1027.PubMedGoogle Scholar
  41. Goldenfeld, N., Baron-Cohen, S., & Wheelwright, S. (2006). Empathizing and systemizing in males, females and autism. Clinical Neuropsychiatry 2.Google Scholar
  42. Greenberg, D. A., Hodge, S. E., Sowinski, J., & Nicoll, D. (2001). Excess of twins among affected sibling pairs with autism: implications for the etiology of autism. American Journal of Human Genetics, 69(5), 1062–1067.PubMedGoogle Scholar
  43. Griffith, E. M., Pennington, B. F., Wehner, E. A., & Rogers, S. J. (1999). Executive functions in young children with autism. Child Development, 70(4), 817–832.PubMedGoogle Scholar
  44. Hallmayer, J., Glasson, E. J., Bower, C., Petterson, B., Croen, L., Grether, J., et al. (2002). On the twin risk in autism. American Journal of Human Genetics, 71(4), 941–946.PubMedGoogle Scholar
  45. Happé, F. G. E. (1994). Wechsler IQ profile and theory of mind in autism: a research note. Journal of Child Psychology and Psychiatry, 35, 1461–1471.PubMedGoogle Scholar
  46. Happé, F. G. E. (1997). Central coherence and theory of mind in autism: reading homographs in context. British Journal of Developmental Psychology, 15, 1–12.Google Scholar
  47. Happé, F. (2000). Parts and wholes, meaning and minds: Central coherence and its relation to theory of mind. In S. Baron-Cohen, H. Tager-Flusberg, & D. Cohen (Eds.), Understanding other minds: Perspectives from autism and developmental cognitive neuroscience. Oxford: Oxford University Press.Google Scholar
  48. Happé, F. (2001). Social and non-social development in Autism:Where are the links. In J. A. Burack, T. Charman, N. Yirmiya, & P. R. Zelazo (Eds.), Perspectives on development in autism. NJ: Erlbaum.Google Scholar
  49. Happé, F. (2003). Cognition in autism: One deficit or many? Autism:Neural basis and treatment possibilities (Novartis Foundation Symposium 251) pp. 198–212. Chichester: Wiley.Google Scholar
  50. Happé, F., Booth, R., Charlton, R., & Hughes, C. (2006). Executive function deficits in autism spectrum disorders and attention-deficit/hyperactivity disorder: examining profiles across domains and ages. Brain & Cognition, 61(1), 25–39.Google Scholar
  51. Happé, F., Briskman, J. & Frith, U. (2001). Exploring the cognitive phenotype of autism: Weak ‘central coherence’ in parents and siblings of children with autism. I. Experimental tests. Journal of Child Psychology and Psychiatry, 42, 299–307.PubMedGoogle Scholar
  52. Happé, F. & Frith, U. (2006). The weak coherence account: Detail-focused cognitive style in autism spectrum disorders. Journal of Autism and Developmental Disorders, 36, 5–25.PubMedGoogle Scholar
  53. Hill, E. L. (2004). Evaluating the theory of executive dysfunction in autism. Developmental Review, 24(2), 189–233.Google Scholar
  54. Hill, E. L. (2004). Executive dysfunction in autism. Trends in Cognitive Sciences, 8(1), 26–32.PubMedGoogle Scholar
  55. Hirschhorn, J. N., & Daly, M. J. (2005). Genome-wide association studies for common diseases and complex traits. Nature Reviews Genetics, 6(2), 95–108.PubMedGoogle Scholar
  56. Hoekstra, R. A., Bartels, M., Cath, D. C., & Boomsma, D. I. (2008). Factor structure, reliability and criterion validity of the autism-spectrum quotient (AQ): A study in Dutch population and patient groups. J Autism Dev Disord, 38(8), 1555–1566.PubMedGoogle Scholar
  57. Hughes, C., Leboyer, M., & Bouvard, M. (1997). Executive function in parents of children with autism. Psychological Medicine, 27(1), 209–220.PubMedGoogle Scholar
  58. Hultman, C. M., Sparen, P., & Cnattingius, S. 2002, “Perinatal risk factors for infantile autism”, Epidemiology, 13(4), 417–423.PubMedGoogle Scholar
  59. Jarrold, C., Butler, D. W., Cottington, E. M., & Jimenez, F. (2000). Linking theory of mind and central coherence bias in autism and in the general population. Developmental Psychology, 36, 126–138.PubMedGoogle Scholar
  60. Johnson, K. A., Robertson, I. H., Kelly, S. P., Silk, T. J., Barry, E., Daibhis, A., et al. (2007). Dissociation in performance of children with ADHD and high-functioning autism on a task of sustained attention. Neuropsychologia, 45(10), 2234–45.PubMedGoogle Scholar
  61. Jolliffe, T., & Baron-Cohen, S. (2000). Linguistic processing in high-functioning adults with autism or Asperger’s syndrome. Is global coherence impaired? Psychological Medicine, 30, 1169–1187.PubMedGoogle Scholar
  62. Joseph, J. (2002). Twin studies in psychiatry and psychology: science or pseudoscience? Psychiatric Quarterly, 73(1), 71–82.PubMedGoogle Scholar
  63. Just, M. A., Cherkassky, V. L., Keller, T. A., Kana, R. K., & Minshew, N. J. (2007). Functional and anatomical cortical underconnectivity in autism: evidence from an FMRI study of an executive function task and corpus callosum morphometry. Cerebral Cortex, 17(4), 951–61.PubMedGoogle Scholar
  64. Kamin, L. J., & Goldberger, A. S. (2002). Twin studies in behavioral research: a skeptical view. Theoretical Population Biology, 61(1), 83–95.PubMedGoogle Scholar
  65. Kanner, L., & Eisenberg, L. (1956). Early infantile autism 1943–1955. American Journal of Orthopsychiatry, 26, 55–65.Google Scholar
  66. Knickmeyer, R., Baron-Cohen, S., Raggatt, P., & Taylor, K. (2005). Foetal testosterone, social cognition, and restricted interests in children. Journal of Child Psychology and Psychiatry, 45, 1–13.Google Scholar
  67. Kolevzon, A., Smith, C. J., Schmeidler, J., Buxbaum, J. D., & Silverman, J. M. (2004). Familial symptom domains in monozygotic siblings with autism. American Journal of Medical Genetics, 129B(1), 76–81.PubMedGoogle Scholar
  68. Lauritsen, M. B., Pedersen, C. B., & Mortensen, P. B. (2004). The incidence and prevalence of pervasive developmental disorders: A Danish population-based study. Psychological Medicine, 34(7), 1339–1346.PubMedGoogle Scholar
  69. Le Couteur, A., Bailey, A., Goode, S., Pickles, A., Robertson, S., Gottesman, I., et al. (1996). A broader phenotype of autism: the clinical spectrum in twins. Journal of Child Psychology & Psychiatry & Allied Disciplines, 37(7), 785–801.Google Scholar
  70. Lecavalier, L. (2005). An evaluation of the Gilliam Autism Rating Scale. J Autism Dev Disord, 35(6), 795–805.PubMedGoogle Scholar
  71. Lopez, B. R., Lincoln, A. J., Ozonoff, S., & Lai, Z. (2005). Examining the relationship between executive functions and restricted, repetitive symptoms of autistic disorder. Journal of Autism and Developmental Disorders, 35(4), 445–460.PubMedGoogle Scholar
  72. Maccoby, E. E. (2000). Parenting and its effects on children: on reading and misreading behavior genetics. Annual Review of Psychology, 51, 1–27.PubMedGoogle Scholar
  73. MacLean, J. E., Szatmari, P., Jones, M. B., Bryson, S. E., Mahoney, W. J., Bartolucci, G., et al. (1999). Familial factors influence level of functioning in pervasive developmental disorder, Journal of the American Academy of Child & Adolescent Psychiatry, 38(6), 746–753.CrossRefGoogle Scholar
  74. Mandy, W. P., & Skuse, D. H. (2008). Research review: what is the association between the social-communication element of autism and repetitive interests, behaviours and activities? J Child Psychol Psychiatry, 49(8), 795–808.PubMedGoogle Scholar
  75. Manjaly, Z. M., Bruning, N., Neufang, S., Stephan, K. E., Brieber, S., Marshall, J. C., et al. (2007). Neurophysiological correlates of relatively enhanced local visual search in autistic adolescents. Neuroimage, 35(1), 283–291.PubMedGoogle Scholar
  76. Martin, N., Boomsma, D., & Machin, G. (1997). A twin-pronged attack on complex traits. Nat.Genet, 17(4), 387–392.PubMedGoogle Scholar
  77. Mazefsky, C. A., Goin-Kochel, R. P., Riley, B. P., Maes, H. H., & The Autism Genetic Resource Exchange Consortium (2008). Genetic and environmental influences on symptom domains in twins and siblings with autism. Research in Autism Spectrum Disorders, 2, 320–331.PubMedGoogle Scholar
  78. McCauley, J. L., Olson, L. M., Dowd, M., Amin, T., Steele, A., Blakely, R. D., et al. (2004). Linkage and association analysis at the serotonin transporter (SLC6A4) locus in a rigid-compulsive subset of autism. American Journal of Medical Genetics, 127B(1), 104–112.PubMedGoogle Scholar
  79. 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.PubMedGoogle Scholar
  80. Minshew, N. J., & Goldstein, G. (1998). Autism as a disorder of complex information processing. Mental Retardation and Developmental Disabilities Research Reviews, l4(2), 129–136.Google Scholar
  81. Miranda-Linne, F. M., & Melin, L. (2002). A factor analytic study of the Autism Behavior Checklist. Journal of Autism and Developmental Disorders, 32(3), 181–188.PubMedGoogle Scholar
  82. Morgan, B., Maybery, M., & Durkin, K. (2003). Weak central coherence, poor joint attention, and low verbal ability: Independent deficits in early autism. Developmental Psychology, 39, 646–656.PubMedGoogle Scholar
  83. Mottron, L., Dawson, M., Soulières, I., Hubert, B., & Burack, J. A. (2006). Enhanced perceptual functioning in autism: an updated model, and eight principle of autistic perception. Journal of Autism and Developmental Disorders, special issue: Perception in Autism, 36, 27–43.Google Scholar
  84. Mulder, E. J., Anderson, G. M., Kema, I. P., Brugman, A. M., Ketelaars, C. E., de Bildt, A., et al. (2005). Serotonin transporter intron 2 polymorphism associated with rigid-compulsive behaviors in Dutch individuals with pervasive developmental disorder. American Journal of Medical Genetics B Neuropsychiatric Genetics, 133B(1), 93–96.Google Scholar
  85. Myhr, G. (1998). Autism and other pervasive developmental disorders: exploring the dimensional view. Canadian Journal of Psychiatry, 43(6), 589–595.Google Scholar
  86. Nurmi, E. L., Dowd, M., Tadevosyan-Leyfer, O., Haines, J. L., Folstein, S. E., & Sutcliffe, J. S. (2003). Exploratory subsetting of Autism families based on savant skills improves evidence of genetic linkage to 15q11–q13. Journal of the American Academy of Child & Adolescent Psychiatry, 42(7), 856–863.Google Scholar
  87. Ohnishi, T., Matsuda, H., Hashimoto, T., Kunihiro, T., Nishikawa, M., Uema, T., et al. (2000). Abnormal regional cerebral blood flow in childhood autism. Brain, 123(Pt 9), 1838–1844.PubMedGoogle Scholar
  88. Ozonoff, S., & Jensen, J. (1999). Specific executive function profiles in three neurodevelopmental disorders. Journal of Autism and Developmental Disorders, 29(2), 171–177.PubMedGoogle Scholar
  89. Ozonoff, S., Pennington, B. F., & Rogers, S. J. (1991). Executive function deficits in high-functioning autistic individuals: relationship to theory of mind. Journal of Child Psychology and Psychiatry, 32(7), 1081–1105.PubMedGoogle Scholar
  90. Ozonoff, S., South, M. & Provencal, S. (2005). Executive Functions. In, Volkmar, F. R., Paul, R., Klin, A. & Cohen, D. (Eds), Handbook of autism and pervasive developmental disorders, Vol. 1: Diagnosis, development, neurobiology, and behavior (3rd ed.). (pp. 606–627). xxv, 703 pp. Hoboken, NJ, US: John Wiley & Sons Inc.Google Scholar
  91. Pickles, A., Starr, E., Kazak, S., Bolton, P., Papanikolaou, K., Bailey, A., et al. (2000). Variable expression of the autism broader phenotype: findings from extended pedigrees. Journal of Child Psychology & Psychiatry & Allied Disciplines, 41(4), 491–502.Google Scholar
  92. Piven, J., Palmer, P., Jacobi, D., Childress, D., & Arndt, S. (1997). Broader autism phenotype: evidence from a family history study of multiple-incidence autism families. American Journal of Psychiatry, 154(2), 185–190.PubMedGoogle Scholar
  93. Plaisted, K. C. (2001). Reduced generalization in autism: An alternative to weak central coherence. In J. A. Burack, T. Charman, N. Yirmiya, & P. R. Zelazo (Eds.), The development of autism: Perspectives from theory and research (pp. 149–169). Mahwah, NJ: Erlbaum.Google Scholar
  94. Pellicano, E. (2007). Links between theory of mind and executive function in young children with autism: clues to developmental primacy. Developmental Psychology, 43(4), 974–990.PubMedGoogle Scholar
  95. Pellicano, E., Maybery, M., & Durkin, K. (2005). Central coherence in typically developing preschoolers: does it cohere and does it relate to mindreading and executive control? Journal of Child Psychology and Psychiatry, 46(5), 533–547.PubMedGoogle Scholar
  96. Pellicano, E., Maybery, M., Durkin, K., & Maley, A. (2006). Multiple cognitive capabilities/deficits in children with an autism spectrum disorder: “Weak” central coherence and its relationship to theory of mind and executive control. Development and Psychopathology, 18(1), 77–98.PubMedGoogle Scholar
  97. Perner, J., Stummer, S., & Lang, B. (1999). Executive functions and theory of mind: Cognitive complexity or functional dependence? In P. D. Zelazo, J. W. Astington, & D. R. Olson (Eds.), Developing theories of intention: Social understanding and self-control (pp. 133–152). Mahwah, NJ, US: Erlbaum xi, 358 pp.Google Scholar
  98. Plomin, R., DeFries, J. C., McClearn, G. E., & McGuffin, P. (2008). Behavioral Genetics (4th ed.). New York: Worth.Google Scholar
  99. Rippon, G., Brock, J., Brown, C., & Boucher, J. (2007). Disordered connectivity in the autistic brain: challenges for the “new psychophysiology”. International Journal of Psychophysiology, 63(2), 164–172.PubMedGoogle Scholar
  100. Risch, N. J. (2000). Searching for genetic determinants in the new millennium. Nature, 405(6788), 847–856.PubMedGoogle Scholar
  101. Ritvo, E. R., Freeman, B. J., Mason-Brothers, A., Mo, A., & Ritvo, A. M. (1985). Concordance for the syndrome of autism in 40 pairs of afflicted twins. American Journal of Psychiatry, 142(1), 74–77.PubMedGoogle Scholar
  102. Ronald, A. (2006). Quantitative Genetic Study of Autistic-Like Traits in Middle Childhood: Evidence from a Population Twin Sample for Genetic Heterogeneity Between the Behaviours that Characterise Autism Spectrum Conditions. University of London (unpublished thesis).Google Scholar
  103. Ronald, A., Happé, F., & Plomin, R. (2005). The genetic relationship between individual differences in social and nonsocial behaviours characteristic of autism. Developmental Science, 8, 444–458.PubMedGoogle Scholar
  104. Ronald, A., Happé, F., Bolton, P., Butcher, L. M., Price, T. S., Wheelwright, S., et al. (2006a). Genetic heterogeneity between the three components of the autism spectrum: a twin study. Journal of the American Academy of Child & Adolescent Psychiatry, 45, 691–699.Google Scholar
  105. Ronald, A., Happe, F., Price, T. S., Baron-Cohen, S., & Plomin, R. (2006b). Phenotypic and genetic overlap between autistic traits at the extremes of the general population. Journal of the American Academy of Child & Adolescent Psychiatry, 45, 1206–1214.Google Scholar
  106. Rose, S., Lewontin, R. C., & Kamin, L. J. (1984). Not in our genes: Biology, ideology and human nature. London: Penguin.Google Scholar
  107. Russell, J. (1997). Ed. Autism as an executive disorder. New York, NY, US: Oxford University Press.Google Scholar
  108. Russell, J., & Hill, E. L. (2001). Action-monitoring and intention reporting in children with autism. Journal of Child Psychology and Psychiatry, 42(3), 317–328.PubMedGoogle Scholar
  109. Rutter, M. (1968). Concepts of autism: a review of research. Journal of Child Psychology & Psychiatry & Allied Disciplines, 9(1), 1–25.Google Scholar
  110. Rutter, M. (1978). Diagnosis and definition of childhood autism. Journal of Autism and Childhood Schizophrenia, 8, 139–161.PubMedGoogle Scholar
  111. Rutter, M. (2005). Aetiology of autism: findings and questions. Journal of Intellectual Disability Research, 49(Pt 4), 231–238.PubMedGoogle Scholar
  112. Schellenberg, G. D., Dawson, G., Sung, Y. J., Estes, A., Munson, J., Rosenthal, E., et al. (2006). Evidence for multiple loci from a genome scan of autism kindreds. Molecular Psychiatry, 11(11), 1049–1060 1979.PubMedGoogle Scholar
  113. Schmitz, N., Rubia, K., Daly, E., Smith, A., Williams, S., & Murphy, D. G. (2006). Neural correlates of executive function in autistic spectrum disorders. Biological Psychiatry, 59(1), 7–16.PubMedGoogle Scholar
  114. Scott, F. J., Baron-Cohen, S., Bolton, P., Brayne, C. (2002). The CAST (Childhood Asperger Syndrome Test): Preliminary Development of a UK Screen for Mainstream Primary-School-Age Children. Autism, 6, 9–31.PubMedGoogle Scholar
  115. Shaked, M., & Yirmiya, N. (2004). Matching procedures in autism research: evidence from meta-analytic studies. Journal of Autism and Developmental Disorders, 34(1), 35–40.PubMedGoogle Scholar
  116. Sham, P. C., Cherny, S. S., Purcell, S., & Hewitt, J. K. (2000). Power of linkage versus association analysis of quantitative traits, by use of variance-components models, for sibship data. American Journal of Human Genetics, 66(5), 1616–1630.PubMedGoogle Scholar
  117. Shao, Y., Cuccaro, M. L., Hauser, E. R., Raiford, K. L., Menold, M. M., Wolpert, C. M., et al. (2003). Fine mapping of autistic disorder to chromosome 15q11–q13 by use of phenotypic subtypes. American Journal of Human Genetics, 72(3), 539–548.PubMedGoogle Scholar
  118. Shao, Y., Raiford, K. L., Wolpert, C. M., Cope, H. A., Ravan, S. A., Ashley-Koch, A. A., et al. (2002). Phenotypic homogeneity provides increased support for linkage on chromosome 2 in autistic disorder. American Journal of Human Genetics, 70(4), 1058–1061.PubMedGoogle Scholar
  119. Siegel, B., Anders, T. F., Ciaranello, R. D., Bienenstock, B., & Kraemer, H. C. (1986). Empirically derived subclassification of the autistic syndrome. Journal of Autism and Developmental Disorders, 16(3), 275–293.PubMedGoogle Scholar
  120. Sigman, M., & McGovern, C. W. (2005). Improvement in cognitive and language skills from preschool to adolescence in autism. Journal of Autism and Developmental Disorders, 35, 15–23.PubMedGoogle Scholar
  121. Silani, G., Bird, G., Brindley, R., Singer, T., Frith, C., & Frith, U. (2008). Levels of emotional awareness and autism: an fMRI study. Social Neuroscience, 3(2), 97–112.PubMedGoogle Scholar
  122. Silverman, J. M., Smith, C. J., Schmeidler, J., Hollander, E., Lawlor, B. A., Fitzgerald, M., et al. (2002). Symptom domains in autism and related conditions: evidence for familiality. American Journal of Medical Genetics, 114(1), 64–73.PubMedGoogle Scholar
  123. Spiker, D., Lotspeich, L., Kraemer, H. C., Hallmayer, J., McMahon, W., Petersen, P. B., et al. (1994). Genetics of autism: characteristics of affected and unaffected children from 37 multiplex families. American Journal of Medical Genetics, 54(1), 27–35.PubMedGoogle Scholar
  124. Steffenburg, S., Gillberg, C., Hellgren, L., Andersson, L., Gillberg, I. C., Jakobsson, G., et al. (1989). A twin study of autism in Denmark, Finland, Iceland, Norway and Sweden. Journal of Child Psychology & Psychiatry & Allied Disciplines, 30(3), 405–416.Google Scholar
  125. Stella, J., Mundy, P., & Tuchman, R. (1999). Social and nonsocial factors in the Childhood Autism Rating Scale. Journal of Autism and Developmental Disorders, 29(4), 307–317.PubMedGoogle Scholar
  126. Sung, Y. J., Dawson, G., Munson, J., Estes, A., Schellenberg, G. D., & Wijsman, E. M. (2005). Genetic investigation of quantitative traits related to autism: use of multivariate polygenic models with ascertainment adjustment. American Journal of Human Genetics, 76(1), 68–81.PubMedGoogle Scholar
  127. Sutcliffe, J. S., Delahanty, R. J., Prasad, H. C., McCauley, J. L., Han, Q., Jiang, L., et al. (2005). Allelic heterogeneity at the serotonin transporter locus (SLC6A4) confers susceptibility to autism and rigid-compulsive behaviors. American Journal of Human Genetics, 77(2), 265–279.PubMedGoogle Scholar
  128. Sykes, N. H., & Lamb, J. A. (2007). Autism: the quest for the genes. Expert Reviews in Molecular Medicine, 9(24), 1–15.PubMedGoogle Scholar
  129. Szatmari, P. (1999). Heterogeneity and the genetics of autism. Journal of Psychiatry and Neuroscience, 24(2), 159–165.PubMedGoogle Scholar
  130. Szatmari, P., Georgiades, S., Bryson, S., Zwaigenbaum, L., Roberts, W., Mahoney, W., et al. (2006). Investigating the structure of the restricted, repetitive behaviours and interests domain of autism. Journal of Child Psychology and Psychiatry, 47, 582–590.PubMedGoogle Scholar
  131. Szatmari, P., Jones, M. B., Holden, J., Bryson, S., Mahoney, W., Tuff, L., et al. (1996). High phenotypic correlations among siblings with autism and pervasive developmental disorders. American Journal of Medical Genetics, 67(4), 354–360.PubMedGoogle Scholar
  132. Szatmari, P., MacLean, J. E., Jones, M. B., Bryson, S. E., Zwaigenbaum, L., Bartolucci, G., et al. (2000). The familial aggregation of the lesser variant in biological and nonbiological relatives of PDD probands: a family history study. Journal of Child Psychology & Psychiatry & Allied Disciplines, 41(5), 579–586.Google Scholar
  133. Szatmari, P., Merette, C., Bryson, S. E., Thivierge, J., Roy, M. A., Cayer, M., et al. (2002). Quantifying dimensions in autism: a factor-analytic study. Journal of the American Academy of Child & Adolescent Psychiatry, 41(4), 467–474.Google Scholar
  134. Tadevosyan-Leyfer, O., Dowd, M., Mankoski, R., Winklosky, B., Putnam, S., McGrath, L., et al. (2003). A principal components analysis of the autism diagnostic interview—revised. Journal of the American Academy of Child & Adolescent Psychiatry, 42(7), 864–872.Google Scholar
  135. Tordjman, S., Gutknecht, L., Carlier, M., Spitz, E., Antoine, C., Slama, F., et al. (2001). Role of the serotonin transporter gene in the behavioral expression of autism. Molecular Psychiatry, 6(4), 434–439.PubMedGoogle Scholar
  136. Turner, M. (1999). Repetitive behaviour in autism: a review of psychological research. Journal of Child Psychology and Psychiatry, 40(6), 839–849.PubMedGoogle Scholar
  137. van Lang, N. D., Boomsma, A., Sytema, S., de Bildt, A. A., Kraijer, D. W., Ketelaars, C., et al. (2006). Structural equation analysis of a hypothesised symptom model in the autism spectrum. J Child Psychol Psychiatry, 47(1), 37–44.PubMedGoogle Scholar
  138. Visscher, P. M. (2002). Increased rate of twins among affected sib pairs. Am. J Hum. Genet, 71(4), 995–996.PubMedGoogle Scholar
  139. Volkmar, F. R., Cicchetti, D. V., Dykens, E., Sparrow, S. S., Leckman, J. F., & Cohen, D. J. (1988). An evaluation of the Autism Behavior Checklist. Journal of Autism and Developmental Disorders, 18(1), 81–97.PubMedGoogle Scholar
  140. Wadden, N. P. K., Bryson, S. E., & Ridger, R. S. (1991). A closer look at the autism behavior checklist: discriminant validity and factor structure. Journal of Autism & Developmental Disorders, 21(4), 529–541.Google Scholar
  141. Wagner, G., Koch, K., Reichenbach, J. R., Sauer, H., & Schlosser, R. G. M. (2006). The special involvement of the rostrolateral prefrontal cortex in planning abilities(:) an event-related fMRI study with the Tower of London paradigm. Neuropsychologia, 44(12), 2337–2347.PubMedGoogle Scholar
  142. Walker, D. R., Thompson, A., Zwaigenbaum, L., Goldberg, J., Bryson, S. E., Mahoney, W. J. et al. (2004). Specifying PDD-NOS: a comparison of PDD-NOS, Asperger syndrome, and autism. Journal of the American Academy of Child & Adolescent Psychiatry, 43(2), 172–180.Google Scholar
  143. Wing, L. (1981). Language, social, and cognitive impairments in autism and severe mental retardation. Journal of Autism and Developmental Disorders, 11(1), 31–44.PubMedGoogle Scholar
  144. Wing, L., & Gould, J. (1978). Systematic recording of behaviors and skills of retarded and psychotic children. Journal of Autism and Childhood Schizophrenia, 8(1), 79–97.PubMedGoogle Scholar
  145. 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(1), 11–29.PubMedGoogle Scholar
  146. Wing, L., Yeates, S. R., Brierley, L. M., & Gould, J. (1976). The prevalence of early childhood autism: comparison of administrative and epidemiological studies. Psychological Medicine, 6(1), 89–100.PubMedCrossRefGoogle Scholar
  147. Yang, M. S., & Gill, M. (2007). A review of gene linkage, association and expression studies in autism and an assessment of convergent evidence. International Journal of Developmental Neuroscience, 25(2), 69–85.PubMedGoogle Scholar
  148. Zelazo, P. D., Burack, J. A., Boseovski, J. J., Jacques, S., & Frye, D. (2001). A cognitive complexity and control framework for the study of autism. In J. A. Burack, T. Charman, N. Yirmiya, & P. R Zelazo (Eds.), The development of autism: Perspectives from theory and research (pp. 195–217). Mahwah, NJ, US: Erlbaum.Google Scholar

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© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.MRC Social, Genetic and Developmental Psychiatry Centre, Institute of PsychiatryKing’s College LondonLondonUK
  2. 2.Centre for Brain and Cognitive DevelopmentBirkbeck CollegeLondonUK

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