A longitudinal study of cortical EEG activity in adolescents

BackgroundThe objective of this study is to test Davidson's, and Heller and Nitschke's models stating cortical activity in adolescents to be a marker for increased risk for depression.MethodsAlpha activity was measured in 80 adolescents from medial-frontal (F3/4), lateral-frontal (F7/8), and medial-parietal (P3/4) electrodes, as well as self-reported depression and anxiety twice within 12 months. Step-wise hierarchical regression analyses with anxiety as covariate were calculated with alpha asymmetry as predicting variable and depression as target variable and vice versa.ResultsIndependent of whether anxiety was used as covariate or not, frontal and parietal alpha asymmetry predict depression, but depression did not predict alpha activity.ConclusionsThe results partially support both models and conclusions drawn by studies with remitted depressed subjects. However, it remains unclear if anxious arousal has a partial influence on the predictive association between alpha activity and depression.