Test-retest consistency of the event-related desynchronization/event-related synchronization of the 4-6, 6-8, 8-10 and 10-12 Hz frequency bands during a memory task

Objective: The aim of this study was to determine the test-retest consistency of the event-related desynchronization/event-related synchronization (ERD/ERS) method during the performance of an auditory memory task. Methods: The EEG was recorded while 12 subjects performed an auditory memory task on two separate occasions (mean test-retest interval 9 days). Differences in the ERD/ERS responses between the first and second registrations were examined in 4 EEG frequency bands of interest: 4-6, 6-8, 8-10 and 10-12 Hz. Results: We observed significant differences in the ERD/ERS responses between the first and second registration In all studied frequency bands when examined as a function of time and experimental task. The test-retest reliability of the ERD/ERS values was highest in the theta frequency range (4-6 and 6-8 Hz), poorer in the 8-10 Hz and poorest in the 10-12 Hz alpha frequency range. Conclusions: The test-retest effect was seen in the ERD/ERS responses of all studied frequency bands during an auditory memory task. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.