The evaluation of response to pharmacological treatment in MDD requires 6–8 weeks. Therefore, the ability to predict response, and especially lack of response to treatment, as early as possible after treatment onset or change, is of major significance. Many studies demonstrated significant results regarding the ability to use EEG and ERP markers. However, these markers are derived from long EEG/ERP samples, often from multiple channels, which render them impractical for frequent sampling.

We developed a new electrophysiological attention-related marker from a single channel (2 electrodes) and 1 minute samples. This work presents an initial evaluation of the ability to harness this marker, for early differentiation between responders and non-responders to anti-depressive treatment, in 26 patients with various levels of depression and heterogeneous treatment interventions and 10 healthy controls. Subjects who initiated treatment for depression were followed clinically through their Hamilton depression scores as well as their EEG activity twice a week for a period of 8 weeks. Any acceptable anti-depressive treatment been included. The improvement in Hamilton scores at the end of 8 weeks used to discriminate responders and non-responders.

Within two weeks, we could differentiate between non-responders and responders to anti-depressive treatment, with absolute discrimination between subjects with moderate to severe depression, and with 0.71 sensitivity and 0.96 specificity within the whole depressed subjects.

This is a proof of concept for an easy to use, cheap and quick marker for the lack of respond to anti-depressive treatment within two weeks of anti-depressive treatment.