The Relationship between EEG Changes and Cognitive Functions in Dementia: A Study in a VA Population

This study explores the relationship between the results of tests of dementia and the EEG findings in 94 demented patients of different etiologies. Abnormal EEGs were found in 83% of all patients, usually diffuse slow wave abnormalities, the degree of which correlated very well with the Modified Hachinski test. Only a weak relationship was found between the EEG and the Mini-Mental Status Examination, while the Mattis and its subtests correlated better. Focal EEG abnormalities on the temporal areas were the characteristic pattern in patients with alcoholic dementia. The test scores in the 17% with normal EEGs were consistent with the above findings, in that patients with normal tracings scored well on the Modified Hachinski and Mattis tests, but not on the Mini-Mental Status Exam.