Abstract:

The asymmetry of resting frontal activity was examined when differential activation of the alpha frequency band of left and right frontal cortex was found, i.e., frontal EEG lateralization. It had been showed largely that resting frontal EEG asymmetry was related to depression. Based on worldwide studies, we found that there was a negative correlation between resting frontal EEG asymmetry and depression level. Compared with individuals without depressive symptoms, those with depressive symptoms showed enhancement of right frontal activity. For depressive individuals, resting frontal EEG asymmetry was stable in the short and long run. That is to say, resting frontal EEG asymmetry predicted the risk of depression, which showed that frontal EEG asymmetry could be regarded as a neural index of depressive symptoms. In addition, resting frontal EEG asymmetry reflected the activation of dorsolateral prefrontal cortex, which might play a role in developing depressive symptoms. Future studies should focus on the neural mechanism of resting frontal EEG asymmetry predicting depression, the application of frontal EEG symmetry predicting depressive symptoms, and training methods (e.g., mindfulness training) to change the resting frontal EEG asymmetry of depressive individuals, relieving the depression level.

Key words: depression, frontal EEG lateralization, frontal EEG asymmetry, neural index