The results indicated that ‘group’ had a main effect on dipole P300 amplitude (F(2,94) = 3.36; P = 0.042). More specifically, the depressive disorder group displayed lower dipole amplitudes when compared with anxiety disorder patients (F(1,94) = 7.86, P < 0.01) and the healthy control group (F(1,94) = 8.83, P < 0.01).