Figure 5.

Typical examples of EEG and EMG recordings and corresponding hypnograms in mice treated with vehicle or modafinil at 180 mg/kg. A–G, WT mice were treated with vehicle (A), modafinil only (B), SCH23390 + modafinil (C), or raclopride + modafinil (D), and D₂R KO mice were treated with vehicle (E), modafinil only (F), and SCH23390 + modafinil (G). The open arrows indicate pretreatment with D₁R or D₂R antagonists or its vehicle, and closed arrows represent the time of modafinil injection or its vehicle. W, Wakefulness; R, REM sleep; N, NREM sleep.