Table 2.
Genioglossus reflex characteristics to negative-pressure pulse stimuli during wakefulness and NREM sleep
| Wake | Stage 2 | SWS | |
|---|---|---|---|
| Excitation phase | |||
| Onset latency (ms) | 26 ± 1 | 23 ± 1 | 25 ± 2 |
| Peak amplitude (% baseline) | 231 ± 29 | 249 ± 16 | 218 ± 11 |
| Peak latency (ms) | 38 ± 3 | 32 ± 2 | 34 ± 2 |
| Duration (ms) | 23 ± 2 | 16 ± 1 | 17 ± 2 |
| Suppression phase | |||
| Onset latency (ms) | 47 ± 2 | 39 ± 2 | 42 ± 2 |
| Nadir amplitude (% baseline) | 67 ± 8 | 39 ± 4* | 46 ± 4* |
| Nadir latency (ms) | 71 ± 4 | 63 ± 3 | 67 ± 2 |
| Duration (ms) | 42 ± 6 | 39 ± 4 | 40 ± 3 |
| Stimulus properties | |||
| Breath onset to pulse onset (ms) | 92 ± 3 | 93 ± 3 | 91 ± 3 |
| Pmask magnitude (cmH2O) | −9.5 ± 0.3 | −10.8 ± 0.3* | −10.7 ± 0.3* |
| Pmask rise time (ms) | 11.3 ± 0.2 | 10.9 ± 0.4 | 11.1 ± 0.4 |
| Pcho magnitude (cmH2O) | −8.3 ± 0.5 | −10.0 ± 0.4* | −9.8 ± 0.6* |
| Number of artefact-free pulse presentations | 53 ± 3 | 27 ± 5* | 40 ± 6* |
Slow wave sleep (SWS), mask (Pmask) and choanal pressures (Pcho). Reflex timing data are quoted in milliseconds (ms). Reflex amplitude data are quoted as percentage baseline of the average EMGgg activity 100 ms prior to pulse onset (% baseline).
*
Significant difference compared to wakefulness. Values are means ± s.e.m. (Data presented are from n = 16 subjects in whom complete data were available during wakefulness, stage 2 NREM and SWS).