EEG differences in children between eyes-closed and eyes-open resting conditions

Objective: Recent work on arousal vs. activation in adults showed that skin conductance levels (SCLs) increased, and global alpha levels decreased, from eyes-closed to eyes-open resting baseline conditions. This study explored whether similar effects occur in children. Methods: EEG activity was recorded from 30 children aged 8-12 years during counterbalanced eyes-closed and eyes-open resting conditions; SCL was measured as an index of arousal. Results: SCLs were negatively correlated with mean alpha levels in the eyes-closed condition, and increased significantly from eyes-closed to eyes-open. Reductions were found in across-scalp mean absolute delta, theta, alpha, and beta from eyes-closed to eyes-open. Topographic changes were evident in all bands except alpha. Conclusions: Results confirm the use of mean alpha level as a measure of resting-state arousal under eyes-closed and eyes-open conditions. Focal changes in the other bands suggest that these reflect differences in activation, rather than the simple increase in arousal shown in alpha. Significance: This child study confirms the generality of eyes-closed vs. eyes-open non-alpha EEG measures differing in mean power levels and topography, the latter indicating brain activity related to visual processing. Such differences should be considered when evaluating EEG research, and in choosing baseline conditions for different paradigms. (C) 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.