Table 3.
Association between baseline sleep measures and behavioral and physiologic measures during prolonged wakefulness.
| Waking measure | Sleep stage (% of TST) | EEG power | |||
|---|---|---|---|---|---|
| S1 | S2 | SWS | SWA | Alpha | |
| Self‐rated sleepiness | −0.41 | −0.39 | 0.29 | 0.22 | −0.58* |
| PVT lapses | −0.68* | −0.30 | 0.02 | 0.26 | −0.13 |
| PVT mean log RT | −0.69* | −0.22 | −0.05 | 0.23 | −0.15 |
| PERCLOS | −0.36 | 0.21 | −0.35 | 0.15 | 0.22 |
| Blink rate | 0.18 | −0.15 | 0.54 | 0.01 | −0.28 |
| Heart rate | 0.36 | 0.43 | −0.25 | −0.09 | −0.13 |
| SDNN | −0.34 | −0.32 | −0.20 | 0.12 | −0.06 |
| EEG delta power | −0.25 | −0.07 | 0.04 | 0.27 | 0.14 |
| EEG theta power | −0.06 | 0.01 | −0.25 | 0.41 | 0.25 |
| EEG alpha power | 0.55 | 0.43 | −0.36 | −0.18 | 0.85*** |
| EEG beta power | 0.73** | 0.66* | −0.52 | −0.36 | 0.52 |
For baseline sleep measures that showed stable between‐subject differences across study visits, we examined whether subject rankings were similar for behavioral and physiologic measures that were reproducible across repeated exposures to sleep deprivation. Results are shown for Stage 1 sleep (S1), Stage 2 sleep (S2), slow wave sleep (SWS), EEG spectral power for slow wave activity (SWA) in NREM sleep, and EEG spectral power in the alpha frequency band during REM sleep. For each subject and outcome measure, data were averaged across study visits and compared using Spearman's correlation analysis. Spearman's rho is shown for each comparison, with the level of statistical significance indicated by the asterisks: *P <0.05; **P <0.01; ***P <0.001. PVT, psychomotor vigilance task; RT, response time; PERCLOS, percentage eyelid closure over the pupil over time; SDNN, standard deviation of normal‐to‐normal RR intervals; EEG, electroencephalogram.