The study was one part of study which studied the effect of tDCS on cognition, recruited 57 health male, average age 23.61 ± 1.62 years (range 21–27 years). Twenty participants were underwent this part of study, in which 8 participants were delivered with 2 mA, 30 min tDCS on F3 anode F4 cathode (active group), 12 participants were in the sham tDCS group (sham group). Seven participants in active group and 8 in the ham group were analyzed (Fig. 1). All participants had PVT mean reaction time declined within 18 to 28 hours extended wakefulness. There were no statistically difference in the extended wakefulness time to performing tDCS (p = 0.773) between active group (21.4 h ± 1.57 h) and sham group (20.75h ± 3.20 h). The t-tests exposed no difference of minor lapses (500 ms-1000 ms) of PVT (p = 0.826), major lapses ( > = 1000 ms) of PVT (p = 0.318), anticipations of PVT (p = 0.356), mean reaction time of PVT (p = 0.324 ), TMT A time (p = 0.354 ), TMT B time (p = 0.065), mean DCT-scores achieved for 2-digits targets matrix within the time limit of 20 s (p = 0.225) and 30 s (p = 0.543), mean DCT-scores achieved for 3-digits targets matrix within the time limit of 20 s (p = 0.789) and 30 s (p = 0.385), BVMT scores (p = 0.524), the fatigue scores (p = 0.070), and the SSS scores ( p = 0.056) between the active group and sham group in the session before the tDCS treatment. The t-tests exposed a significant difference of mean reaction time of SCWT-A (sham 840.43 ± 168.81 ms, F3 + F4- 1072.04 ± 175.52 ms, p = 0.028), mean reaction time of SCWT-B (sham 825.65 ± 207.98 ms, F3 + F4- 1012.36 ± 75.37 ms, p = 0.042), KSS (sham 4.63 ± 1.69, F3 + F4- 6.57 ± 1.72, p = 0.046) between the active group and sham group in the session before the tDCS treatment. (Table 1 and Fig. 2–6)
Table 1
Performance of the last session before tDCS
| Sham | Active | p |
| Mean | ± | SD | Mean | ± | SD |
PVT Minor Lapses (n) | 9.88 | ± | 4.94 | 9.29 | ± | 5.25 | 0.826 |
PVT Major Lapses (n) | 0.88 | ± | 1.36 | 2.00 | ± | 2.71 | 0.318 |
PVT Anticipations (n) | 0.00 | ± | 0.00 | 0.14 | ± | 0.38 | 0.356 |
PVT Mean RT (ms) | 361.08 | ± | 28.99 | 397.52 | ± | 96.20 | 0.324 |
TMT-A time (s) | 72.00 | ± | 26.22 | 84.29 | ± | 22.76 | 0.354 |
TMT-B time(s) | 86.88 | ± | 17.18 | 116.43 | ± | 33.45 | 0.065 |
DCT scores 2–20 s | 14.32 | ± | 3.60 | 11.95 | ± | 3.58 | 0.225 |
DCT scores 3–20 s | 16.36 | ± | 2.37 | 14.27 | ± | 8.36 | 0.543 |
DCT scores 2–30 s | 18.04 | ± | 1.29 | 17.81 | ± | 1.98 | 0.789 |
DCT scores 3–30 s | 22.33 | ± | 4.12 | 19.89 | ± | 6.28 | 0.385 |
SCWT-A Mean RT (ms) | 840.43 | ± | 168.81 | 1072.04 | ± | 175.52 | 0.028* |
SCWT-B Mean RT (ms) | 825.65 | ± | 207.98 | 1012.36 | ± | 75.37 | 0.042* |
BVMT scores | 29.43 | ± | 5.53 | 27.29 | ± | 6.63 | 0.524 |
Fatigue | 4.25 | ± | 2.05 | 6.43 | ± | 2.23 | 0.070 |
KSS | 4.63 | ± | 1.69 | 6.57 | ± | 1.72 | 0.046* |
SSS | 3.63 | ± | 1.41 | 4.86 | ± | 0.69 | 0.056 |
BVMT-R: the Brief visuospatial memory test-revised, DCT scores 2-20s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 20 s, DCT scores 3-20s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 20 s, DCT scores 2-30s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 30 s, DCT scores 3-30s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 30 s, Fatigue: Fatigue visual analog scale, KSS: Karolinska Sleepiness Scale, PVT: Psychomotor vigilance task, SCWT-A: Stroop color and word test A, SCWT-B: Stroop color and word test B, tDCS: transcranial direct current stimulation, TMT-A: Trail making test A, TMT-B: Trail making testB, SSS: Stanford Sleepiness Scale |
Transient Effect of tDCS
The t-tests exposed a significantly better outcome of major lapses (≥ 1000 ms) of PVT (p = 0.003), mean reaction time of PVT (p = 0.019), mean DCT-scores achieved for 2-digits targets matrix within the time limit of 20 s (p = 0.025), mean DCT-scores achieved for 3-digits targets matrix within the time limit of 30 s (p = 0.008), mean reaction time of SCWT-A (p = 0.002), the fatigue scores (p = 0.032), the KSS scores (p = 0.011) and the SSS scores (p = 0.014), between the active group and sham group in the change from the last session before the treatment to the first session after treatment. Compared with sham group, the change from the last session before the tDCS treatment to the first session after the treatment in active group were better tendency, but there were no statistically significant difference in minor lapses (500 ms-1000 ms) of PVT (p = 0.170), anticipations of PVT (p = 0.356), TMT A time (p = 0.320), TMT B time (p = 0.257), mean DCT-scores achieved for 2-digits targets matrix within the time limit of 20 s ( p = 0.025) and 30 s( p = 0.355), mean reaction time of SCWT-B ( p = 0.463 ) and BVMT scores (p = 0.804). (Table 2 and Fig. 2–6)
Table 2
Performance change from last session before tDCS to the first session after tDCS
| Sham | Active | p |
| Mean | ± | SD | Mean | ± | SD |
PVT Minor Lapses (n) | 0.63 | ± | 7.27 | -3.43 | ± | 2.23 | 0.170 |
PVT Major Lapses (n) | 0.38 | ± | 0.52 | -1.14 | ± | 1.07 | 0.003* |
PVT Anticipations (n) | 0.25 | ± | 0.46 | 0.43 | ± | 0.79 | 0.595 |
PVT Mean RT (ms) | 8.26 | ± | 47.72 | -58.63 | ± | 48.51 | 0.019* |
TMT-A time (s) | -1.25 | ± | 19.91 | -15.86 | ± | 33.95 | 0.320 |
TMT-B time(s) | 9.25 | ± | 20.23 | -9.86 | ± | 40.29 | 0.257 |
DCT scores 2–20 s | -0.97 | ± | 3.17 | 4.38 | ± | 4.96 | 0.025* |
DCT scores 3–20 s | 0.38 | ± | 2.97 | 3.95 | ± | 9.13 | 0.355 |
DCT scores 2–30 s | -0.42 | ± | 1.99 | -1.41 | ± | 7.09 | 0.708 |
DCT scores 3–30 s | -0.70 | ± | 2.76 | 5.27 | ± | 4.48 | 0.008* |
SCWT-A Mean RT (ms) | 61.99 | ± | 88.32 | -129.63 | ± | 94.91 | 0.002* |
SCWT-B Mean RT (ms) | 26.04 | ± | 111.97 | -41.00 | ± | 220.95 | 0.463 |
BVMT scores | 0.00 | ± | 4.04 | 0.71 | ± | 6.26 | 0.804 |
Fatigue | 0.38 | ± | 1.51 | -1.29 | ± | 1.11 | 0.032* |
KSS | 0.50 | ± | 0.53 | -1.14 | ± | 1.21 | 0.011* |
SSS | 0.25 | ± | 0.71 | -1.00 | ± | 1.00 | 0.014* |
BVMT-R: the Brief visuospatial memory test-revised, DCT scores 2-20s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 20 s, DCT scores 3-20s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 20 s, DCT scores 2-30s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 30 s, DCT scores 3-30s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 30 s, Fatigue: Fatigue visual analog scale, KSS: Karolinska Sleepiness Scale, PVT: Psychomotor vigilance task, RT: reaction time, SCWT-A: Stroop color and word test A, SCWT-B: Stroop color and word test B, tDCS: transcranial direct current stimulation, TMT-A: Trail making test A, TMT-B: Trail making test B, SSS: Stanford Sleepiness Scale
After-effects of tDCS
There were significant difference of the change from the last session before the treatment to the second session after the tDCS treatment in TMT B time (p = 0.013), fatigue (p = 0.012), KSS (p = 0.031) and SSS (p = 0.006) between the active group and sham group. Compared with sham group, the change from the last session before the tDCS treatment to the second session after the treatment in active group had the tendency to be better, but no statistically significant difference in minor lapses (500 ms-1000 ms) of PVT (p = 0.690),major lapses (≥ 1000 ms) of PVT (p = 0.555), anticipations of PVT (p = 0.098), mean reaction time of PVT (p = 0.340), TMT A time (p = 0.395), mean DCT-scores achieved for 2-digits targets matrix within the time limit of 20 s (p = 0.346) and 30 s (p = 0.349), 3-digits targets matrix within the time limit of 20 s (p = 0.804) and 30 s (p = 0.661), mean reaction time of SCWT-A (p = 0.086), and mean reaction time of SCWT-B (p = 0.080), and BVMT scores (p = 0.321). (Table 3 and Fig. 2–6)
Table 3
Performance change from last time before tDCS to 2 hours later after tDCS
| Sham | Active | p |
| Mean | ± | SD | Mean | ± | SD |
PVT Minor Lapses (n) | 6.63 | ± | 8.37 | 4.43 | ± | 12.35 | 0.690 |
PVT Major Lapses (n) | 3.00 | ± | 4.72 | 1.29 | ± | 6.24 | 0.555 |
PVT Anticipations (n) | 0.25 | ± | 0.46 | -0.14 | ± | 0.38 | 0.098 |
PVT Mean RT (ms) | 119.58 | ± | 150.26 | 33.35 | ± | 186.99 | 0.340 |
TMT-A time (s) | 5.25 | ± | 22.80 | -4.43 | ± | 19.29 | 0.395 |
TMT-B time(s) | 29.50 | ± | 19.82 | -19.86 | ± | 43.52 | 0.013* |
DCT scores 2–20 s | -0.99 | ± | 3.91 | 1.03 | ± | 4.09 | 0.346 |
DCT scores 3–20 s | -0.66 | ± | 3.23 | -1.61 | ± | 10.07 | 0.804 |
DCT scores 2–30 s | 0.21 | ± | 1.47 | -2.94 | ± | 3.54 | 0.349 |
DCT scores 3–30 s | -0.46 | ± | 4.88 | -1.60 | ± | 5.04 | 0.661 |
SCWT-A Mean RT (ms) | 37.51 | ± | 122.74 | -119.27 | ± | 192.13 | 0.086 |
SCWT-B Mean RT (ms) | 29.71 | ± | 165.23 | -104.01 | ± | 90.56 | 0.080 |
BVMT scores | -3.29 | ± | 5.77 | 0.60 | ± | 7.16 | 0.321 |
Fatigue | 1.75 | ± | 1.58 | -0.43 | ± | 1.27 | 0.012* |
KSS | 1.63 | ± | 1.41 | -0.71 | ± | 2.29 | 0.031* |
SSS | 1.25 | ± | 0.71 | -0.29 | ± | 1.11 | 0.006* |
BVMT-R: the Brief visuospatial memory test-revised, DCT scores 2-20s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 20 s, DCT scores 3-20s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 20 s, DCT scores 2-30s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 30 s, DCT scores 3-30s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 30 s, Fatigue: Fatigue visual analog scale, KSS: Karolinska Sleepiness Scale, PVT: Psychomotor vigilance task, RT: reaction time, SCWT-A: Stroop color and word test A, SCWT-B: Stroop color and word test B, tDCS: transcranial direct current stimulation, TMT-A: Trail making test A, TMT-B: Trail making test B, SSS: Stanford Sleepiness Scale
Postrecovery sleep effects of tDCS
There were no difference found in minor lapses (500 ms-1000 ms) of PVT (p = 0.393), major lapses (≥ 1000 ms) of PVT (p = 0.926), anticipations of PVT (p = 0.926), mean reaction time of PVT (p = 0.680), TMT A time (p = 0.878), TMT B time (p = 0.335), mean DCT-scores achieved for 2-digits targets matrix within the time limit of 20 s (p = 0.634) and 30 s (p = 0.795), mean DCT-scores achieved for 3-digits targets matrix within the time limit of 30 s (p = 0.356), BVMT scores (p = 0.603), the fatigue scores (p = 0.620), KSS( p = 0.328) and the SSS scores ( p = 0.508) between the active group and sham group in the session after recovery sleep. Only mean DCT-scores achieved for 3-digits targets matrix within the time limit of 20 s (p = 0.017) was found significantly better in the active group in the session after recovery sleep (Table 4). There were no difference found for all tests between the change of tests post-sleep after sleep deprivation from 10 o’clock tests between the active group and sham group (Table 5). Compared with 10 o’clock session, all tests after recovery of sleep deprivation had better trend, in which PVT anticipations (p = 0.005), mean DCT-scores achieved for 3-digits targets matrix within the time limit of 20 s (p = 0.005), mean reaction time of SCWT-A (p = 0.026), SCWT-B (p = 0.009 ) and fatigue were significantly different. (Table 6,and Fig. 2–6)
Table 4
Performance postrecovery sleep
| Sham | Active | p |
| Mean | ± | SD | Mean | ± | SD |
PVT Minor Lapses (n) | 1.38 | ± | 2.20 | 2.71 | ± | 3.59 | 0.393 |
PVT Major Lapses (n) | 0.13 | ± | 0.35 | 0.14 | ± | 0.38 | 0.926 |
PVT Anticipations (n) | 0.13 | ± | 0.35 | 0.14 | ± | 0.38 | 0.926 |
PVT Mean RT (ms) | 275.88 | ± | 28.16 | 284.77 | ± | 51.80 | 0.680 |
TMT-A time (s) | 55.25 | ± | 8.76 | 56.29 | ± | 16.21 | 0.878 |
TMT-B time(s) | 76.88 | ± | 24.35 | 91.57 | ± | 32.45 | 0.335 |
DCT scores 2–20 s | 16.57 | ± | 2.29 | 15.87 | ± | 3.22 | 0.634 |
DCT scores 3–20 s | 15.83 | ± | 3.23 | 21.46 | ± | 4.68 | 0.017* |
DCT scores 2–30 s | 18.88 | ± | 1.61 | 19.11 | ± | 1.85 | 0.795 |
DCT scores 3–30 s | 25.17 | ± | 2.48 | 26.46 | ± | 2.75 | 0.356 |
SCWT-A Mean RT (ms) | 741.03 | ± | 81.73 | 783.24 | ± | 109.25 | 0.408 |
SCWT-B Mean RT (ms) | 740.42 | ± | 111.34 | 719.10 | ± | 113.36 | 0.720 |
BVMT scores | 30.25 | ± | 3.73 | 31.14 | ± | 2.54 | 0.603 |
Fatigue | 1.00 | ± | 1.53 | 1.43 | ± | 1.62 | 0.620 |
KSS | 1.43 | ± | 1.27 | 2.14 | ± | 1.35 | 0.328 |
SSS | 1.43 | ± | 0.79 | 1.86 | ± | 1.46 | 0.508 |
BVMT-R: the Brief visuospatial memory test-revised, DCT scores 2-20s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 20 s, DCT scores 3-20s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 20 s, DCT scores 2-30s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 30 s, DCT scores 3-30s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 30 s, Fatigue: Fatigue visual analog scale, KSS: Karolinska Sleepiness Scale, PVT: Psychomotor vigilance task, RT: reaction time, SCWT-A: Stroop color and word test A, SCWT-B: Stroop color and word test B, TMT-A: Trail making test A, TMT-B: Trail making test B, SSS: Stanford Sleepiness Scale |
Table 5
Performance change from 10 o’clock session on the first day to the session after recovery sleep
| Sham | Active | p |
| Mean | ± | SD | Mean | ± | SD |
PVT Minor Lapses (n) | -1.25 | ± | 2.49 | 0.43 | ± | 4.76 | 0.398 |
PVT Major Lapses (n) | 0.00 | ± | 0.53 | -0.29 | ± | 0.95 | 0.478 |
PVT Anticipations (n) | 0.13 | ± | 0.35 | 0.00 | ± | 0.00 | 0.351 |
PVT Mean RT (ms) | -16.98 | ± | 32.85 | -10.06 | ± | 49.70 | 0.753 |
TMT-A time (s) | -19.25 | ± | 26.51 | -3.00 | ± | 21.06 | 0.241 |
TMT-B time(s) | -17.13 | ± | 26.69 | 1.67 | ± | 23.08 | 0.193 |
DCT scores 2–20 s | 2.86 | ± | 4.74 | 1.20 | ± | 3.31 | 0.480 |
DCT scores 3–20 s | 1.75 | ± | 3.76 | 2.25 | ± | 4.34 | 0.821 |
DCT scores 2–30 s | 1.12 | ± | 2.50 | 1.44 | ± | 3.27 | 0.838 |
DCT scores 3–30 s | 2.22 | ± | 2.70 | 3.42 | ± | 4.95 | 0.572 |
SCWT-A Mean RT (ms) | -138.20 | ± | 142.79 | -64.04 | ± | 125.62 | 0.308 |
SCWT-B Mean RT (ms) | -41.77 | ± | 114.95 | -42.87 | ± | 86.43 | 0.984 |
BVMT scores | 3.00 | ± | 5.66 | 3.00 | ± | 4.32 | 1.000 |
Fatigue | 0.25 | ± | 1.39 | 0.71 | ± | 1.50 | 0.544 |
KSS | -0.50 | ± | 1.31 | 0.43 | ± | 1.62 | 0.241 |
SSS | -0.25 | ± | 1.04 | 0.71 | ± | 1.50 | 0.166 |
BVMT-R: the Brief visuospatial memory test-revised, DCT scores 2-20s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 20 s, DCT scores 3-20s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 20 s, DCT scores 2-30s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 30 s, DCT scores 3-30s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 30 s, Fatigue: Fatigue visual analog scale, KSS: Karolinska Sleepiness Scale, PVT: Psychomotor vigilance task, RT: reaction time, SCWT-A: Stroop color and word test A, SCWT-B: Stroop color and word test B, TMT-A: Trail making test A, TMT-B: Trail making test B, SSS: Stanford Sleepiness Scale |
Table 6
Performance between 10 o’clock on the first day and post recovery sleep
| 10:00 session | Postrecovery sleep session | p |
| Mean | ± | SD | Mean | ± | SD |
PVT Minor Lapses (n) | 2.47 | ± | 2.03 | 2.00 | ± | 2.90 | 0.764 |
PVT Major Lapses (n) | 0.27 | ± | 0.59 | 0.13 | ± | 0.35 | 0.515 |
PVT Anticipations (n) | 0.07 | ± | 0.26 | 0.13 | ± | 0.35 | 0.005* |
PVT Mean RT (ms) | 293.78 | ± | 23.78 | 280.03 | ± | 39.59 | 0.374 |
TMT-A time (s) | 68.93 | ± | 24.55 | 55.73 | ± | 12.30 | 0.445 |
TMT-B time(s) | 93.57 | ± | 20.95 | 83.73 | ± | 28.38 | 0.068 |
DCT scores 2–20 s | 14.34 | ± | 2.62 | 16.25 | ± | 2.68 | 0.389 |
DCT scores 3–20 s | 16.60 | ± | 5.09 | 18.46 | ± | 4.80 | 0.005* |
DCT scores 2–30 s | 17.67 | ± | 2.00 | 18.99 | ± | 1.67 | 0.790 |
DCT scores 3–30 s | 23.38 | ± | 4.04 | 25.77 | ± | 2.60 | 0.129 |
SCWT-A Mean RT (ms) | 864.32 | ± | 165.38 | 760.73 | ± | 94.50 | 0.026* |
SCWT-B Mean RT (ms) | 772.76 | ± | 125.07 | 730.47 | ± | 108.75 | 0.009* |
BVMT scores | 28.14 | ± | 4.67 | 30.67 | ± | 3.15 | 0.447 |
Fatigue | 0.67 | ± | 0.72 | 1.21 | ± | 1.53 | 0.034* |
KSS | 1.73 | ± | 0.80 | 1.79 | ± | 1.31 | 0.282 |
SSS | 1.33 | ± | 0.49 | 1.64 | ± | 1.15 | 0.836 |
BVMT-R: the Brief visuospatial memory test-revised, DCT scores 2-20s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 20 s, DCT scores 3-20s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 20 s, DCT scores 2-30s: Digit cancellation test scores achieved for 2-digits targets matrix within the time limit of 30 s, DCT scores 3-30s: Digit cancellation test scores achieved for 3-digits targets matrix within the time limit of 30 s, Fatigue: Fatigue visual analog scale, KSS: Karolinska Sleepiness Scale, PVT: Psychomotor vigilance task, RT: reaction time, SCWT-A: Stroop color and word test A, SCWT-B: Stroop color and word test B, TMT-A: Trail making test A, TMT-B: Trail making test B, SSS: Stanford Sleepiness Scale
Sleep effect of tDCS
There were no significant difference of recovery sleep architecture such as sleep latency (SL) (p = 0.596), N2 latency (p = 0.757), N3 latency (p = 0.343), rapid eye movement sleep (REM) latency (p = 0.126), time in bed (TIB) (p = 0.849), total sleep time (TST) (p = 0.849), N1 sleep percent (p = 0.999), N2 sleep percent (p = 0.565), N3 sleep percent (p = 0.240), REM sleep percent (p = 0.188), arousal index (p = 0.591), wake after sleep onset (WASO) (p = 0.822) and sleep efficiency (p = 0.889) between the active group and sham group. All participants had shorted sleep latency (sham group vs active group: 1.50 ± 1.71 min, vs 1.89 ± 0.81 min), N2 latency (sham group vs active group: 2.56 ± 2.16 min, 2.93 ± 2.32 min), N3 latency (sham group vs active group: 16.56 ± 20.23 min, 8.79 ± 5.15 min), REM latency (sham group vs active group: 58.88 ± 27.60 min, 81.67 ± 22.77 min), and increased N3 percent (sham group vs active group: 37.86 ± 9.59 min, 45.89 ± 15.37 min). (Table 7)
Table 7
The effect of tDCS on the recovery sleep
| Sham | F3 + F4- | p |
| (Mean | ± | SD) | (Mean | ± | SD) |
Sleep Latency (min) | 1.50 | ± | 1.71 | 1.89 | ± | 0.81 | 0.596 |
N2 Latency (min) | 2.56 | ± | 2.16 | 2.93 | ± | 2.32 | 0.757 |
N3 Latency (min) | 16.56 | ± | 20.23 | 8.79 | ± | 5.15 | 0.343 |
REM Latency (min) | 58.88 | ± | 27.60 | 81.67 | ± | 22.77 | 0.126 |
TIB (min) | 277.63 | ± | 218.71 | 259.01 | ± | 134.77 | 0.849 |
TST (min) | 265.88 | ± | 211.25 | 247.86 | ± | 132.92 | 0.849 |
REM time (min) | 48.38 | ± | 48.98 | 31.79 | ± | 25.18 | 0.435 |
N1 Time (min) | 12.06 | ± | 10.71 | 10.43 | ± | 6.54 | 0.732 |
N2 Time (min) | 119.25 | ± | 122.79 | 107.93 | ± | 80.27 | 0.839 |
N3 Time (min) | 86.19 | ± | 35.88 | 97.71 | ± | 33.37 | 0.533 |
R (%TST) | 15.66 | ± | 6.78 | 10.56 | ± | 7.46 | 0.188 |
N1 (%TST) | 4.69 | ± | 1.83 | 4.69 | ± | 2.10 | 0.999 |
N2 (%TST) | 41.78 | ± | 7.41 | 38.87 | ± | 11.47 | 0.565 |
N3 (%TST) | 37.86 | ± | 9.59 | 45.89 | ± | 15.37 | 0.240 |
Arousal index (n/h) | 6.70 | ± | 2.70 | 5.76 | ± | 3.90 | 0.591 |
WASO (min) | 10.25 | ± | 9.43 | 9.27 | ± | 6.53 | 0.822 |
Sleep Efficiency (%) | 95.28 | ± | 2.63 | 95.07 | ± | 2.91 | 0.889 |
TIB: time in bed, TST: total sleep time, REM: rapid eye movement, WASO: wake after sleep onset