Does frontal brain activity mediate the effect of depression prevention in adolescents? A pilot study.

We investigated whether (a) depression prevention was associated with depressive symptoms and medial-frontal alpha asymmetry in adolescents; (b) alpha asymmetry mediated the association between participation in a prevention program and depressive symptoms; and (c) gender affects these associations. In our randomised control group study, we compared a universal prevention program (n = 40 adolescents, 14 females) with a non-intervention control condition (n = 39 adolescents, 20 females) in German secondary school students (mean age: 13.53 years, SD = 0.53). We collected data at baseline, post-intervention, 6-month, and 12-month follow-up using the Self-Rating Questionnaire for Depressive Disorders (SBB-DES) and resting medial-frontal alpha activity on F3 and F4. We found that girls benefitted from participating in the prevention program in regards to their depressive symptoms at 12-month follow-up but not alpha asymmetry. In boys, participation in the prevention program was associated with their alpha asymmetry at 6-month follow-up but not their depressive symptoms. Alpha asymmetry did not mediate the effects of the prevention program on depressive symptoms in either gender. Although participation in the prevention program was associated with both depressive symptoms and alpha asymmetry, those associations seem independent from each other. Possible explanations for this result pattern are discussed.