The difference of the mean [oxy-Hb] between the task period and rest period in patients with bipolar depression was significantly smaller than the HCs in all seven channels (ch21, ch22, ch23, ch24, ch25, ch26, ch38, F = 0.029–10.892, FDR p < 0.05, p = 0.027–0.046) during the VFT. The gene discussed is GSTM1; the disease is bipolar disorder.