Methamphetamine (METH) 40 mg/kg s.c. can induce repetitive electrographic seizure discharges (RESDs). (A–C) show EEG activity in a control mouse given normal saline. (A) is the baseline recording, (B) is the recording 30 min after saline injection and (C) is the recording 60 min after saline injection. All show low voltage, mixed frequency activity. (D–F) show EEG activity in a mouse given METH that did not develop RESDs. (D) is the baseline recording, (E) is the recording 30 min and (F) is the recording 60 min after METH injection. The EEG activity is similar to that of the control mouse. (G–I) show the EEG activity in a mouse given METH that developed RESDs. (G) is the baseline recording, (H) shows high-amplitude repetitive 5-Hz spike-wave discharges 39 min after METH injection, and I shows repetitive 14-Hz spike-wave discharges 76 min after METH injection. This mouse had intermittent bursts of RESDs over a 37-min period.