Topographical Variation of Equivalent EEG Generators During Cognitive Decline in Patients with Dementia of Alzheimer Type
Since Berger described the human EEG in 1929 (Berger 1929) clinicians as well as researchers have attempted to conceptualize electrical activity of the brain as a reflection of mental processes. Due to recent advances in computer software and hardware it is now possible to sample more electrical information from the brain and make the concept of the EEG as an electrical brain mirror tangible. However, the increasing amount of data make a sensible interpretation of the data difficult. One way to reduce data in a reasonable way is to calculate equivalent dipoles, which describe the electrical activity of the brain as one or more dipoles generating the electrical field over the surface of the scalp. The calculation of dipoles have mostly been accomplished in the time domain, for example, epileptic discharges or evoked potentials. For the investigation of psychiatric diseases, however, the analysis of frequency bands is of higher interest than an analysis of the time domain.
KeywordsCognitive Decline Peak Frequency Alzheimer Type Topographical Variation Beta Activity
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