Open AccessSpatial‐temporal structures of human alpha rhythms: Theory, microcurrent sources, multiscale measurements, and global binding of local networks
Author(s) -
Nunez Paul L.,
Wingeier Brett M.,
Silberstein Richard B.
Publication year - 2001
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.1030
Subject(s) - electroencephalography , context (archaeology) , neocortex , neuroscience , alpha (finance) , alpha wave , synchronization (alternating current) , alpha rhythm , human brain , coherence (philosophical gambling strategy) , physics , psychology , statistical physics , computer science , artificial intelligence , biological system , biology , developmental psychology , paleontology , construct validity , channel (broadcasting) , computer network , quantum mechanics , psychometrics
Abstract A theoretical framework supporting experimental measures of dynamic properties of human EEG is proposed with emphasis on distinct alpha rhythms. Robust relationships between measured dynamics and cognitive or behavioral conditions are reviewed, and proposed physiological bases for EEG at cellular levels are considered. Classical EEG data are interpreted in the context of a conceptual framework that distinguishes between locally and globally dominated dynamic processes, as estimated with coherence or other measures of phase synchronization. Macroscopic (scalp) potentials generated by cortical current sources are described at three spatial scales, taking advantage of the columnar structure of neocortex. New EEG data demonstrate that both globally coherent and locally dominated behavior can occur within the alpha band, depending on narrow band frequency, spatial measurement scale, and brain state. Quasi‐stable alpha phase structures consistent with global standing waves are observed. At the same time, alpha and theta phase locking between cortical regions during mental calculations is demonstrated, consistent with neural network formation. The brain‐binding problem is considered in the context of EEG dynamic behavior that generally exhibits both of these local and global aspects. But specific experimental designs and data analysis methods may severely bias physiological interpretations in either local or global directions. Hum. Brain Mapping 13:125–164, 2001. © 2001 Wiley‐Liss, Inc.