Alzheimer's disease: relationship between cognitive aspects and power and coherence EEG measures.
OBJECTIVE
To evaluate the relationship between specific cognitive aspects and quantitative EEG measures, in patients with mild or moderate Alzheimer's disease (AD).


METHODS
Thirty-eight AD patients and 31 controls were assessed by CERAD neuropsychological battery (Consortium to Establish a Registry for AD) and the electroencephalogram (EEG). The absolute power and coherences EEG measures were calculated at rest. The correlations between the cognitive variables and the EEG were evaluated.


RESULTS
In the AD group there were significant correlations between different coherence EEG measures and Mini-Mental State Examination, verbal fluency, modified Boston naming, word list memory with repetition, word list recall and recognition, and constructional praxis (p<0.01). These correlations were all negative for the delta and theta bands and positive for alpha and beta. There were no correlations between cognitive aspects and absolute EEG power.


CONCLUSIONS
The coherence EEG measures reflect different forms in the relationship between regions related to various cognitive dysfunctions.
Faculdade de Medicina, Pontifícia Universidade Católica de Campinas, SP, Brazil. lineu.fonseca@uol.com.br
Lineu C
LC
Fonseca
Gloria M A S
GM
Tedrus
Larissa R
LR
Prandi
Adriana M
AM
Almeida
Danilo S
DS
Furlanetto
D000368:Aged; D000544:Alzheimer Disease / Q000150:complications / Q000503:physiopathology*; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology*; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D012720:Severity of Illness Index