Figure 4. Cumulative time in NR and REM sleep over the first 2, 4 and 6 h following drug administration.

(A–C) Cumulative time spent in NR sleep following SB-334867 (A), EMPA (B) and almorexant (C) compared to zolpidem (ZOL). (A’–C’) Cumulative time spent in REM sleep for the same drug treatments. (One-way repeated measures ANOVA followed by paired two-tail t tests; n = 8 per group). Data represent the mean±SEM. *, significantly different from vehicle; +, significantly different from ZOL.