Table 5.

Mean ± SEM spent in each sleep stage during experiment 2 (overnight study)

	Stim	Sham	p Value
W	1.55% (0.69)	4.11% (3.21)	0.44
N1	3.61% (1.00)	2.19% (0.64)	0.23
N2	44.50% (3.47)	39.33% (3.89)	0.33
SWS	39.69% (3.34)	40.85% (4.32)	0.83
REM	9.25% (1.35)	7.39% (1.48)	0.36
MA	1.39% (0.29)	0.89% (0.20)	0.17
Total sleep time (min)	394.4 (15.6)	398.5 (11.1)	0.83

Sleep characteristics during the 210 min stimulation period showing the average time spent in each sleep stage demonstrates that the percentage of time spent in each condition (W, wake; N1, stage 1; N2, stage 2; MA, muscle artifact) was similar during the stimulation period, suggesting that stimulation did not disrupt sleep or increase the overall time spent in NREM sleep.