title: Interpreting EEG alpha activity.
abstract: Exploring EEG alpha oscillations has generated considerable interest, in particular with regards to the role they play in cognitive, psychomotor, psycho-emotional and physiological aspects of human life. However, there is no clearly agreed upon definition of what constitutes 'alpha activity' or which of the many indices should be used to characterize it. To address these issues this review attempts to delineate EEG alpha-activity, its physical, molecular and morphological nature, and examine the following indices: (1) the individual alpha peak frequency; (2) activation magnitude, as measured by alpha amplitude suppression across the individual alpha bandwidth in response to eyes opening, and (3) alpha "auto-rhythmicity" indices: which include intra-spindle amplitude variability, spindle length and steepness. Throughout, the article offers a number of suggestions regarding the mechanism(s) of alpha activity related to inter and intra-individual variability. In addition, it provides some insights into the various psychophysiological indices of alpha activity and highlights their role in optimal functioning and behavior.
authors.affiliation: Institute of Molecular Biology and Biophysics, Siberian Branch, Russian Academy of Medical Sciences, Novosibirsk 630117, Russia. Electronic address: bazanova@soramn.ru.
authors.forename: O M
authors.initials: OM
authors.lastname: Bazanova
authors.affiliation: Department of Applied Social Sciences, Canterbury Christ Church University, Canterbury, Kent, UK. Electronic address: david.vernon@canterbury.ac.uk.
authors.forename: D
authors.initials: D
authors.lastname: Vernon
mesh_terms: D000513:Alpha Rhythm / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D006801:Humans
keywords: Alpha amplitude suppression; Individual alpha bandwidth; Individual alpha peak frequency; Intra-spindle amplitude variability; Spindle-form segments length