Dyscalculia in the early stages of Alzheimer's disease.
OBJECTIVE
To study mathematical deficits in the early stages of Alzheimer's disease (AD).


METHODS
Sixty-eight patients with mild AD and 242 normal controls (NC) received a standardized battery (EC 301-R) assessing number processing and calculation abilities. AD patients also received testing for language, memory, visuo-spatial and executive-attentional domains.


RESULTS
Sixty-four AD patients (94.1%) showed impaired performances on the EC 301-R. Mathematical deficits were evident both on calculation and number processing skills. Performance on the single tasks was related to attentional-executive resources and to impaired number representations. Heterogeneous patterns of preserved/impaired mathematical abilities were also observed in single cases.


CONCLUSIONS
Dyscalculia is an early sign of AD. It should be included among the reliable clinical hallmarks for the diagnosis of AD. Identification of dyscalculic symptoms in these patients requires composite assessment procedure.
Carlomagno
S
S
Istituto di Scienze Neurologiche, Facoltà di Medicina e Chirurgia, Seconda Università degli Studi di Napoli, Italia.
Iavarone
A
A
Nolfe
G
G
Bourène
G
G
Martin
C
C
Deloche
G
G
D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000503:physiopathology*; D018450:Disease Progression; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D009483:Neuropsychological Tests; D011340:Problem Solving / Q000502:physiology*; D014836:Volition / Q000502:physiology