Temporal stability of posterior EEG alpha over twelve years. Issue 7 (July 2018)

• Record Type: Journal Article
• Authors: Tenke, Craig E.; Kayser, Jürgen; Alvarenga, Jorge E.; Abraham, Karen S.; Warner, Virginia; Talati, Ardesheer; Weissman, Myrna M.; Bruder, Gerard E.
• Is Part Of: Clinical neurophysiology. Volume 129:Issue 7(2018:Jul.)
• Page Start: 1410
• Page End: 1417
• Publication Date: 2018-07
• Subjects: EEG -- Temporal stability -- Trait biomarker -- Surface Laplacian -- Current source density (CSD) -- Principal components analysis (PCA); Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2018.03.037
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: Evaluates test-retest reliability of posterior EEG alpha at rest in recordings separated by 12 years. Reliability was excellent in adults for overall alpha and acceptable for net and overall asymmetry. Reliability was substantially weaker in children or adolescents (aged <18 at first test session). Abstract: Objective: We previously identified posterior EEG alpha as a potential biomarker for antidepressant treatment response. To meet the definition of a trait biomarker or endophenotype, it should be independent of the course of depression. Accordingly, this report evaluated the temporal stability of posterior EEG alpha at rest. Methods: Resting EEG was recorded from 70 participants (29 male; 46 adults), during testing sessions separated by 12 ± 1.1 years. EEG alpha was identified, separated and quantified using reference-free methods that combine current source density (CSD) with principal components analysis (PCA). Measures of overall (eyes closed-plus-open) and net (eyes closed-minus-open) posterior alpha amplitude and asymmetry were compared across testing sessions. Results: Overall alpha was stable for the full sample (Spearman-Brown [ r SB ] = .834, Pearson's r = .718), and showed excellent reliability for adults ( r SB = .918; r = 0.848). Net alpha showed acceptable reliability for adults ( r SB = .750; r = .600). Hemispheric asymmetries (right-minus-left hemisphere) of posterior overall alpha showed significant correlations, but revealed acceptable reliability only for adults ( r SB = .728; r = .573). Findings were highly comparable between 29 male and 41 female participants. Conclusions: Overall posterior EEG alpha amplitude is reliable over long time intervals in adults. Significance: The temporal stability of posterior EEG alpha oscillations at rest over long time intervals is indicative of an individual trait.