GSTM1 and Alzheimer disease: Compared with MCI subjects, mild AD patients showed significant lower differences of Oxy-Hb level between the task and rest in channel 25 and channel 43 [mean with 95% CI, mAD vs. MCI, CH25: −0.0042 (−0.0208, 0.0126) vs. 0.0397 (0.0228, 0.0567), p = 0.0005; CH43: −0.0001 (−0.0101, 0.0098) vs. 0.0287 (0.0156, 0.0418), p = 0.0007; all after FDR corrected].