Exceptional calendar calculation ability after early left hemispherectomy

doi:10.1016/0278-2626(91)90013-X

Brain and Cognition

Volume 15, Issue 1, January 1991, Pages 26-36

https://doi.org/10.1016/0278-2626(91)90013-X Get rights and content

Abstract

An 18-year-old male subject who had had his left hemisphere removed at age eight was better than chance at calculating the day of the week upon which dates in the past and future fell. He was able to describe his method of calculation, which relied upon both visual memory and serial calculations. The use of a serial calculation method was supported by evidence that both response time and accuracy were related to the distance in years from the current year. The use of both visual and verbal “working” memory was supported by interference effects from calendar calculations and delayed visual and verbal memory tasks. The case is discussed in terms of theories regarding similar calculation skills in idiot savants.

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^☆: An earlier version of this paper was presented at the 96th Annual Convention of The American Psychological Association at Atlanta, GA, August 1988.

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Exceptional calendar calculation ability after early left hemispherectomy☆

Abstract

Special “isolated” abilities in severely psychotic young children

Psychiatry Journal for the Study of Interpersonal Processes

Adaptive and maladaptive behavior of idiot savants

American Journal of Mental Deficiency

Frequency of eidetic imagery among hydrocephalic children

Perceptual and Motor Skills

Eidetic imagery: Longitudinal results in brain damaged children

American Journal of Mental Deficiency

A case study of an “autistic-savant”: Mental function in the psychotic child with markedly discrepant abilities

Journal of Child Psychology and Psychiatry

An investigation of calendar calculating by an idiot savant

American Journal of Psychiatry

Idiot savants: Rate of incidence

Perceptual and Motor Skills