Comprehensive spectral analysis of human EEG generators in posterior cerebral regions

摘要: Abstract Continuous spectral analyses of several minutes normal human EEGs were prepared by computer, and converted to compact graphic forms. This new presentation voluminous data in contour maps gives an overview the evolution patterns EEG. Parameters graphed intensity (“power density”), coherence, a quantity expressing strength relationship between brain areas. In one subject, strongest relations among longitudinally oriented parieto-occipital linkages, representing subject's alpha wave. Wave activity similar frequency band, recorded across occipital midline, was completely incoherent with Thus, two independent generation processes same orthogonally polarized, are required account for these records. Low O1O2 leads related only partially heart-beat. second there somewhat greater coherence from side than homolateral centro-parietal pairs leads. The configuration geometrically orthogonal statistically uncorrelated generators observed this subject. Of 28 other analyzed way, eighteen showed clear perpendicularity, seven but less marked, while three no such pattern. illustrative subject also coherences flanking his alpha-wave peaks, covering band considerably wider (2–5 c/sec) those high (0.5–1.0 c/sec). Eighteen 25 subjects disparity width. Mathematical constraints implied common finding perpendicular alphaband presented. wide coherent bands (C3-P3/C4-P4) interpreted as possibly due shared “side-bands” wave; features led suggestion that much local not sides is caused activity, or at least causally connected it.