[Cerebral mapping in patients with dementia of Alzheimer's type].

INTRODUCTION: The electric cerebral activity maps complement the conventional electroencefalography quantifying electric cerebral activity. One of the applications is in Alzheimer's dementia. OBJECT: The object of this study is to analyse the differences in the electric cerebral activity, by means a quantified EEG, in DAT and SDAT when compared with a control group of the same age. MATERIAL AND METHODS: Thirty patients meeting the criteria of probabledementia (NINCDS-ADRDA) in the senile (n = 19) and presenile (n = 11) form were studied. They were compared with a control group of the same age, 20 individuals older than and 17 younger than 65. RESULTS: The patients suffering from senile dementia as well as those suffering from the presenile form showed a significative increase of the delta and theta bands. On the other hand, a significant reduction of the alfa frequency bands and mainly those of beta was observed in the patients with ADT but not in the ADST ones. The significant increase of the slow bands in ADT and ADST and the significant decrease of the fast bands in ADT have been found in wide areas. Topographically the biggest affect has been registered in the frontal regions for the beta bands in ADT. CONCLUSIONS: The differences found in the electrical activity, depending on the age, would support Alzheimer's disease heterogeneity.