Fig. 3

Alterations in the sleep architecture of the PLCβ4^−/− mice. a-c Representative scatter plot displaying light-phase awake, NREM, and REM episodes of various lengths. The PLCβ4^−/− mice show long NREM and REM episodes that are not observed in PLCβ4^+/+ mice. d The number of long awake episodes (≥15 min) was decreased in the PLCβ4^−/− mice during the light phase. e The number of long NREM episodes (≥10 min) was significantly increased, and the short NREM episodes (<10 min) were reduced during the light phase in the PLCβ4^−/− mice. f The number of overall (S + L) and short REM episodes (<3 min) was reduced during the light phase in the PLCβ4^−/− mice. The number of long REM episodes (≥3 min) was increased in the PLCβ4^−/− mice. g-i Representative scatter plot of dark-phase awake, NREM, and REM episodes with various lengths. j The number of short awake events (<15 min) was increased, and the long awake episodes (≥15 min) were reduced during the dark phase in the PLCβ4^−/− mice. The overall number of awake episodes was significantly increased in the PLCβ4^−/− mice. k During the dark phase, the overall number of NREM episodes was increased with more frequent occurrence of the short NREM episodes (<10 min) in the PLCβ4^−/− mice. l The number of long REM episodes (≥3 min) was increased in the PLCβ4^−/− mice, whereas the number of short REM episodes (<3 min) did not differ between the two genotypes during the dark phase. Each episode is categorized as short (S) or long (L) according to duration (see Methods) and the dotted line indicates the criterion dividing the S and L episodes. All of the data from the PLCβ4^+/+ (n = 8) and PLCβ4^−/− mice (n = 9) are presented as mean ± SEM. *, p < 0.05; **, p < 0.01; ***, p < 0.005