title: Space-oriented EEG segmentation reveals changes in brain electric field maps under the influence of a nootropic drug.
abstract: Map landscape-based segmentation of the sequences of momentary potential distribution maps (42-channel recordings) into brain microstates during spontaneous brain activity was used to study brain electric field spatial effects of single doses of piracetam (2.9, 4.8, and 9.6 g Nootropil UCB and placebo) in a double-blind study of five normal young volunteers. Four 15-second epochs were analyzed from each subject and drug condition. The most prominent class of microstates (covering 49% of the time) consisted of potential maps with a generally anterior-posterior field orientation. The map orientation of this microstate class showed an increasing clockwise deviation from the placebo condition with increasing drug doses (Fisher's probability product, p < 0.014). The results of this study suggest the use of microstate segmentation analysis for the assessment of central effects of medication in spontaneous multi-channel electroencephalographic data, as a complementary approach to frequency-domain analysis.
authors.affiliation: Department of Neurology, University Hospital, Zurich, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Lehmann
authors.forename: J
authors.initials: J
authors.lastname: Wackermann
authors.forename: C M
authors.initials: CM
authors.lastname: Michel
authors.forename: T
authors.initials: T
authors.lastname: Koenig
mesh_terms: D000328:Adult; D001921:Brain / Q000187:drug effects; D001931:Brain Mapping; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004569:Electroencephalography / Q000187:drug effects*; D004574:Electromagnetic Fields; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D010889:Piracetam / Q000494:pharmacology*; D012815:Signal Processing, Computer-Assisted
chemical_list: D010889:Piracetam