Table 2

Sleep variables derived from visual scoring

Variable

Night [min]

Night [%]

Morning [min]

Morning [%]

Total sleep time

162.92 ± 1.76

165.76 ± 0.97

Sleep efficiency

90.51 ± 0.98

92.37 ± 0.53

WASO

2.39 ± 0.61

5.30 ± 0.83**

Sleep latency

11.47 ± 1.38

5.28 ± 0.58**

REMS latency

72.26 ± 5.54

58.18 ± 4.00°

Movement time

3.28 ± 0.36

2.94 ± 0.30

Stage 1

7.22 ± 0.91

4.56 ± 0.62

12.99 ± 1.80*

7.93 ± 1.10*

Stage 2

93.01 ± 4.29

57.34 ± 2.90

85.50 ± 4.97*

51.55 ± 3.00*

Stage 3

29.43 ± 2.79

17.88 ± 1.60

16.29 ± 2.41**

9.86 ± 1.45**

Stage 4

9.55 ± 2.97

5.76 ± 1.78

3.77 ± 1.57*

2.30 ± 0.95*

SWS

38.98 ± 4.37

23.64 ± 2.52

20.06 ± 3.53**

12.16 ± 2.14**

NREMS

131.99 ± 2.51

80.99 ± 1.22

105.56 ± 3.73**

63.71 ± 2.25**

REMS

23.71 ± 2.17

14.46 ± 1.28

47.21 ± 2.70**

28.36 ± 1.61**

Sleep cycle

89.7 ± 2.4

88.4 ± 4.1

NREMS episode

70.0 ± 2.1

55.62.0**

REMS episode

19.7 ± 1.5

32.7 ± 3.7*

Mean values and standard errors (SEM) are reported (n = 16, 63 night and morning recordings of 16 subjects, except for sleep cycle duration: n = 15, one subject was excluded because of a 'skipped' first REMS episodes in all 4 nights). Mean values were first calculated within subjects prior to averaging across subjects. Stages are in min and in % of total sleep time. For night sleep, only the three first hours after lights out were used for the analyses. Statistics: comparison of night and morning sleep episodes by paired t-tests, * p < 0.01, ** p < 0.001

°n = 9, only subjects with at least one morning sleep episode without SOREMS (Sleep Onset REMS episodes: REMS episodes with latency < 20 min) were included.

WASO: waking after sleep onset; SWS: stages 3 and 4, NREMS: stages 2,3 and 4; REMS latency: time from sleep onset (first occurrence of stage 2) to the first occurrence of REMS.

Tinguely et al. BMC Neuroscience 2006 7:2   doi:10.1186/1471-2202-7-2