Table 2.
Mean ± SEM of supplementary macrostructural and microstructural sleep parameters calculated in this study.
| Sleep parameters | High-recallers | Low-recallers | Standard |
|---|---|---|---|
| Sleep macrostructure | |||
| Awakenings, no. | 17.5 ± 2.1 | 12.1 ± 2.9 | 9.6 (Hirshkowitz, 2004) |
| Awakenings, duration (min) | 1.9 ± 0.2** | 0.95 ± 0.1 | 1.4 (Benoit et al., 1981) |
| Awakenings index, no. per hour | 3.2 ± 0.4 | 2.2 ± 0.6 | 4.2 (Wamsley et al., 2012) |
| N1 | 27.3 ± 4.8 | 34.6 ± 7 | |
| N2 | 3.3 ± 0.7 | 1.8 ± 0.7 | |
| N3 | 0.9 ± 0.2 | 1.1 ± 0.3 | |
| REM | 3.6 ± 1.5 | 1.0 ± 0.3 | |
| Awakenings duration (%) | |||
| 0–1 min | 66.1 ± 3.2** | 82.9 ± 3.3 | 87 (Goldenberg et al., 1981) |
| 1–5 min | 24.6 ± 2.1* | 16.1 ± 3.3 | 11 (Goldenberg et al., 1981) |
| 5–30 min | 9.4 ± 2.5** | 1.0 ± 0.6 | 3 (Goldenberg et al., 1981) |
| Number of stage shifts | 63.6 ± 4.2 | 71.6 ± 7.2 | 47 (Hirshkowitz, 2004) |
| Alpha power (%), in B.S.W | 32 ± 4.6 | 30.5 ± 3.9 | |
| Alpha power (%), in I.S.W | 21 ± 3.1 | 24.4 ± 2.5 | |
| Alpha frequency (Hz), in B.S.W | 9.88 ± 0.1 | 9.86 ± 0.1 | |
| Alpha frequency (Hz), in I.S.W | 9.64 ± 0.1 | 9.65 ± 0.1 | |
| Delta power (%), in first sleep cycle | 79.7 ± 1.7 | 80.8 ± 1.6 | |
| Arousing stimuli (%) | 2.9 ± 0.3** | 1.6 ± 0.2 | |
| Arousing, latency after stim. onset | 5.3 ± 0.2 | 5.8 ± 0.3 | |
| Sleep microstructure | |||
| Arousals, no. | 76.3 ± 8.5 | 61.2 ± 7.2 | 83 (Bonnet and Arand, 2007) |
| Arousals, duration (sec) | 10.2 ± 0.3 | 11.2 ± 0.4 | |
| Arousal index | 11.1 ± 1 | 8.3 ± 1 | 10.8 (Bonnet and Arand, 2007) |
| Spindles, no. per min. of N2 | 3.5 ± 0.3 | 3.5 ± 0.4 | 2.1 (Wamsley et al., 2012) |
| K-complex density, no. per min. of N2 | 2.0 ± 0.2 | 2.5 ± 0.2 | 1–3 (Halász, 2005) |
| REMs, no. per min of REM sleep | 10.9 ± 0.3 | 10.3 ± 0.3 | 3.7 (Andrillon et al., 2015) |
| MTs, no. per min of REM sleep | 0.8 ± 0.1 | 0.8 ± 0.1 |
REMs refers to rapid eye movements; ISW, intra-sleep wakefulness; BSW, before-sleep wakefulness; TST, total sleep time; Normalized spectral power (alpha and delta) is relative to the power in the other frequency bands; MT, muscle twitches; min, minute; no, number. Sleep onset was considered as the first epoch of N2 for the calculation of intra-sleep awakenings. Sleep onset was considered as the first epoch of N1 for arousals. Supplementary Table S1 reports awakening parameters using the first epoch of N1 as sleep onset. Last column represents standard values. One-way and two-way ANOVA for independent samples (High-recallers vs. Low-recallers) are presented: *p < 0.05, **p < 0.01.