Test-retest Reliability of Coherence Measures of qEEG During Resting State
Despite the emphasis in quantitative electroencephalography (qEEG) research on measures of absolute power, recent research has suggested the importance of other qEEG measurements (i.e., coherence and phase lag) as indicators of cognitive function. Coherence has been shown to relate to general intelligence (e.g., Thatcher, et al., 2005), working memory (e.g., Sarnthein et al., 2005) and various neurodevelopmental disorders, such as attention deficit hyperactivity disorder (ADHD; Barry, et al., 2002). As such, qEEG coherence presents a novel measurement of many of the cognitive processes and disorders that school psychologists frequently encounter. Although there is a great deal of research regarding the reliability and validity of absolute power, less exists for these other measures. The current study examined the test-retest reliability of qEEG coherence during a resting state for 40 typically developing students at the University of South Carolina. Results indicated that coherence has moderate to high reliability across all bands and areas of the brain. Additionally, results were consistent with previous literature, suggesting at the alpha and theta ranges exhibited the highest reliability coefficients regardless of location.