Automatic detection     W N1 N2 N3 R Sensitivity (%) Visual detection W 575 18 120 5 16 91 N1 22 238 108 5 29 78 N2 15 10 2280 39 62 80.6 N3 3 1 168 1018 46 91 R 11 3 150 43 1065 87.4 Specificity (%) 90 85 70 87.4 81.2

Table 1: The confusion matrix of a healthy control subject.