Table 3.
The Effects of Stress and Sleep Reactivity on EEG Entropy
| Items | Stress Groups | Control Groups | Stress Effect | SR Effect | Stress × SR | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| H-SR | L-SR | H-SR | L-SR | Statistics | P values | Statistics | P values | Statistics | P values | ||
| Wakefulness | ApEn | 0.99±0.04 | 0.93±0.05 | 0.94±0.05 | 0.91±0.06 | F = 6.733 | 0.012 | F = 15.993 | < 0.001 | F = 1.014 | 0.318 |
| SampEn | 1.51±0.19 | 1.32±0.22 | 1.36±0.18 | 1.25±0.20 | F = 5.338 | 0.024 | F = 7.981 | 0.006 | F = 0.756 | 0.388 | |
| FuzzEn | 1.04±0.17 | 0.93±0.17 | 0.92 (0.83, 0.96) | 0.82 (0.75, 1.02) | H = 4.447 | 0.035 | H = 3.913 | 0.048 | H = 0.690 | 0.406 | |
| MSE | 0.76±0.08 | 0.68±0.09 | 0.69±0.07 | 0.61±0.06 | F = 8.834 | 0.005 | F = 13.797 | < 0.001 | F = 0.001 | 0.970 | |
| REM | ApEn | 0.81±0.12 | 0.75±0.15 | 0.77±0.07 | 0.75±0.07 | F = 0.006 | 0.940 | F = 1.014 | 0.318 | F = 1.216 | 0.275 |
| SampEn | 0.88 (0.75, 1.07) | 0.77 (0.67, 0.99) | 0.86±0.12 | 0.82±0.12 | H = 0.010 | 0.919 | H = 1.293 | 0.256 | H = 0.746 | 0.388 | |
| FuzzEn | 0.61 (0.55, 0.75) | 0.56 (0.49, 0.66) | 0.60±0.07 | 0.58±0.07 | H = 0.438 | 0.508 | H = 1.312 | 0.252 | H = 1.054 | 0.305 | |
| MSE | 0.52 (0.46, 0.61) | 0.50±0.14 | 0.50±0.04 | 0.46±0.05 | H = 0.171 | 0.680 | H = 2.087 | 0.149 | H = 0.886 | 0.346 | |
| N1 | ApEn | 0.95±0.07 | 0.88±0.08 | 0.87±0.07 | 0.86±0.09 | F = 5.805 | 0.019 | F = 4.276 | 0.043 | F = 1.750 | 0.191 |
| SampEn | 1.34±0.27 | 1.16±0.27 | 1.12±0.18 | 1.09±0.24 | F = 6.148 | 0.016 | F = 2.590 | 0.113 | F = 1.732 | 0.193 | |
| FuzzEn | 0.89 (0.76, 0.93) | 0.73 (0.68, 0.98) | 0.75±0.11 | 0.74±0.15 | H = 4.805 | 0.028 | H = 2.302 | 0.129 | H = 1.265 | 0.261 | |
| MSE | 0.69±0.10 | 0.62±0.11 | 0.59±0.07 | 0.53±0.07 | F = 11.929 | 0.001 | F = 6.822 | 0.012 | F = 0.077 | 0.782 | |
| N2 | ApEn | 0.81±0.13 | 0.73±0.13 | 0.74±0.08 | 0.70±0.10 | F = 2.236 | 0.140 | F = 4.222 | 0.044 | F = 0.693 | 0.409 |
| SampEn | 0.83 (0.77, 1.21) | 0.75 (0.65, 0.94) | 0.83±0.14 | 0.78±0.19 | H = 0.834 | 0.361 | H = 4.728 | 0.030 | H = 0.251 | 0.616 | |
| FuzzEn | 0.58 (0.55, 0.81) | 0.52 (0.47, 0.66) | 0.58±0.08 | 0.55±0.11 | H = 1.479 | 0.224 | H = 4.061 | 0.044 | H = 0.372 | 0.542 | |
| MSE | 0.49 (0.44, 0.64) | 0.44 (0.39, 0.52) | 0.47±0.06 | 0.40±0.06 | H = 3.901 | 0.048 | H = 9.830 | 0.002 | H = 0.521 | 0.471 | |
| N3 | ApEn | 0.47 (0.42, 0.71) | 0.44 (0.38, 0.75) | 0.51±0.10 | 0.48±0.10 | H = 0.088 | 0.766 | H = 1.242 | 0.265 | H = 0.478 | 0.489 |
| SampEn | 0.48 (0.39, 0.77) | 0.41 (0.36, 0.84) | 0.51±0.13 | 0.47±0.12 | H = 0.033 | 0.856 | H = 1.137 | 0.286 | H = 0.029 | 0.864 | |
| FuzzEn | 0.36 (0.32, 0.52) | 0.33 (0.29, 0.59) | 0.38±0.07 | 0.37±0.07 | H = 0.041 | 0.840 | H = 0.986 | 0.321 | H = 0.073 | 0.786 | |
| MSE | 0.28 (0.25, 0.41) | 0.26 (0.23, 0.45) | 0.27±0.05 | 0.25±0.05 | H = 0.685 | 0.408 | H = 2.503 | 0.114 | H = 0.176 | 0.675 | |
Notes: Normally or an approximately normally distributed variables are presented as mean ± standard deviation and were analyzed using two-way ANOVA; non-normally distributed variables are presented as P50 (P25, P75) and were analyzed using Scheirer–Ray–Hare test; Significant results (P < 0.05) are in bold; Wakefulness is the time window between the start of EEG recording and sleep onset.
Abbreviations: ApEn, approximate entropy; FuzzEn, fuzzy entropy; H-SR or L-SR, high or low sleep reactivity; MSE, multiscale entropy; N1–3, non-rapid eye movement sleep stages 1–3; REM, rapid eye movement sleep; SampEn, sample entropy.