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.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bowler D. M., Matthews N. J., Gardiner J. M., (1997). Asperger’s syndrome and memory: Similarity to autism but not amnesia Neuropsychologia 35(1): 65–70
Cowan R., O’Connor N., Samella K., (2001). Why and how people of limited intelligence become calendrical calculators Infanzia y aprendizaje 93: 53–65
Dawson, M. (2004). The misbehaviour of behaviourists. http://www.sentex.net/~nexus23/naa_aba.html
Elwood R. W., (1995). The California Verbal Learning Test: Psychometric characteristics and clinical application Neuropsychological Review 5(3):173–201
Farah M., (2000). The cognitive neuroscience of vision Blackwell Publishers, Oxford, 380p
Hill A. L., (1975). An investigation of calendar calculating by an idiot savant American Journal of Psychiatry 132: 557–560
Howe M. J., Smith J., (1988) Calendar calculating in ‘idiots savants’: How do they do it? British Journal of Psychology 79(3): 371–86
Hurst L. C., Mulhall D. J., (1998) Another calendar savant British Journal of Psychiatry 152: 274–177
Kosslyn S. M., Reiser B. J., Farah M. J., Fliegel S. L. (1983). Generating visual images: Units and relations Journal of Experimental Psychology 112(2): 278–303
Lord C., Rutter M., Le Couteur A., (1994). 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(5): 659–686
Lord C., Risi S., Lambrecht L., Cook E. H. Jr, Leventhal B. L., DiLavore P. C., Pickles A., Rutter M. (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(3): 205–223
McClelland J. L., Rumelhardt D. E., (1981). An interactive activation model of contexts effects in letter perception: Part 1. Account of basic findings Psychological Review 88: 375–407
Miller L. K., (1999). The savant syndrome: Intellectual impairment and exceptional skill Psychological Bulletin 125(1): 31–46
Mottron L., Belleville S., (1993). A study of perceptual analysis in a high-level autistic subject with exceptional graphic abilities Brain and Cognition 23: 279–309
Mottron L., Belleville S., (1995). Perspective production in a savant-autistic draugstman Psychological Medicine 25: 639–648
Mottron L., Belleville S., Stip E., (1996). Proper Name Hypermnesia in an autistic subject Brain and Language 53: 326–350
Mottron L., Belleville S., Stip E., Morasse K., (1998). Atypical memory performances in an autistic savant Memory 6(6): 593–607
Mottron L., Belleville S., Ménard E., (1999). Local bias in autistic subjects as evidenced by graphic tasks: perceptual hierchization or working memory deficit Journal of Child Psychology and Psychiatry 40: 743–756
Mottron, L., Dawson, M., Soulières, I., Hubert, & Burack, J., (2006). Enhanced perceptual functioning in autism: An update, and eight principles of autistic perception. Journal of Autism and Developmental Disorders, special issue: perception in autism
O’Connor N., Hermelin B., (1984). Idiot savant calendrical calculators: Maths or memory? Psychological Medicine 14(4): 801–806
Pesenti M., Zago L., Crivello F., Mellet E., Samson D., Duroux B., Seron X., Mazoyer B., Tzourio-Mazoyer N. (2001). Mental calculation in a prodigy is sustained by right prefrontal and medial temporal areas Nature Neuroscience 4(1): 103–107
Seron, X., Dujardin, K., Samson, D., Noël, M.P., & Pesenti, M. (sous presse). Batterie de Calcul UCL-2001 Marseille: Solal Ed
Turkeltaub P. E., Flowers D. L., Verbalis A., Miranda M., Gareau L., Eden G. F., (2004). The neural basis of hyperlexic reading. An FMRI case study Neuron 41(1): 11–25
ACKNOWLEDGMENTS
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”.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mottron, L., Lemmens, K., Gagnon, L. et al. Non-Algorithmic Access to Calendar Information in a Calendar Calculator with Autism. J Autism Dev Disord 36, 239–247 (2006). https://doi.org/10.1007/s10803-005-0059-9
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10803-005-0059-9