Journal of Autism and Developmental Disorders

, Volume 36, Issue 2, pp 239–247 | Cite as

Non-Algorithmic Access to Calendar Information in a Calendar Calculator with Autism

  • L. Mottron
  • K. Lemmens
  • L. Gagnon
  • X. Seron

The possible use of a calendar algorithm was assessed in DBC, an autistic “savant” of normal measured intelligence. Testing of all the dates in a year revealed a random distribution of errors. Re-testing DBC on the same dates one year later shows that his errors were not stable across time. Finally, DBC was able to answer “reversed” questions that cannot be solved by a classical algorithm. These findings favor a non-algorithmic retrieval of calendar information. It is proposed that multidirectional, non-hierarchical retrieval of information, and solving problems in a non-algorithmic way, are involved in savant performances. The possible role of a functional rededication of low-level perceptual systems to the processing of symbolic information in savants is discussed.


Autism calendar calculation savant syndrome autistic intelligence perception 



We acknowledge DBC for his patience in testing, his family for their commitment to research, as well as Michelle Dawson and Marc Thioux for comments on an earlier draft and editing work. This work has been financed by a grant of the Canadian Institute of Mental Health, “characterizing cognitive deficit in Pervasive Developmental Disorders”.


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • L. Mottron
    • 1
    • 2
    • 6
  • K. Lemmens
    • 2
    • 3
  • L. Gagnon
    • 2
    • 4
  • X. Seron
    • 5
  1. 1.Psychiatry DepartmentHôpital Rivière-des-PrairiesMontréalCanada
  2. 2.Clinique Spécialisée de l’AutismeHôpital Rivière-des-PrairiesMontréalCanada
  3. 3.Maastricht UniversityMaastrichtThe Netherlands
  4. 4.Hôpital Sainte-JustineMontréalCanada
  5. 5.Université de Louvain-La-NeuveLouvain-La-NeuveBelgique
  6. 6.Clinique Spécialisée de l’AutismeHôpital Rivière-des-PrairiesMontréalCanada

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